Stall/spin and ground reference maneuvers [Archive]

March 4th 14, 02:43 PM

On Tuesday, March 4, 2014 8:09:16 AM UTC-5, wrote:
> On Tuesday, March 4, 2014 4:54:30 AM UTC-8, John Godfrey (QT) wrote: > On Tuesday, March 4, 2014 7:18:47 AM UTC-5, John Carlyle wrote: > > The insidious part is what you perceive in your peripheral vision unconsciously. True. Peripheral vision is terrible at detail but very good at picking up angular motion. Plus, last time I checked I was looking pretty close to down the wing as I initiated the turn from base to final. Aren't you supposed to look at the runway, not straight ahead into the countryside, on base leg? Once you're established on final there's not much turning anyway. 9B

If you wait till you are wing is almost aligned with the runway, it is likely to be a bit late, commonly leading to a rushed, and possibly skidded turn.
I teach my pilots to check their position on base,clear opposite side for missed traffic on final, decide when they will turn- early is almost always better than late, then watch the nose during the turn so as to keep the pitch attitude correct and avoid skidding the turn. A glance toward the runway will be enough to determine when to start rolling out.
Plenty of folks have spun in looking at the runway or wing tip. few have done so looking over the nose.
Bill's point about making pilots aware of the changing view is a good one and one I think I will add to my lesson points.
FWIW
UH

[email protected]

March 4th 14, 02:54 PM

On Tuesday, March 4, 2014 5:34:09 AM UTC-8, John Carlyle wrote:
> Just because you perceive something doesn't mean that you have to pay attention to it. The most important things in a pattern turn (or low altitude thermalling) are perfectly coordinated turns and proper airspeed. Scans for traffic and feeling for lift are fine, but who cares what the ground does?
>
> One does look at the airport when initiating the turn from base to final, but once the turn starts all you need to do for the next 5 seconds is look over the nose for pitch, yaw and bank. The airport will appear when you need it without having to search for it.
>

Well, it's a human in the loop feedback control system with multiple inputs - visual, inertial and some auditory. If you are making a low turn from base to final you may initiate the turn while looking away from the yaw string and airspeed because the runway is off to the side and you are trying to set a turn rate to put you in-line with the runway on final. At the same time your peripheral vision at this altitude is now subtly telling you that you are over-banked/under-ruddered because you are below the pivotal height where the turning cues of the wing against the background reverse. You aren't used to this peripheral cue and may not be aware of how it affects your overall perception of attitude and coordination and how that feeds back into the control system.

You may be better at it than I am, but I can't just take a snapshot to the side before initiating the turn to final and then look ahead to the yaw string and airspeed without ever looking out to the runway again and expect to end up both pointed at and in-line with the runway heading. I tend to scan back and forth. It only takes a moment of being over-ruddered to generate a spin, particularly if you are at low speed (and an approach into an airport in a mountain valley can make you fly too nose-high if you are not paying proper attention).

Is any of this good and proper airmanship - well no. But that is a little beside the point. The fact is that over the past 20 years 39% of fatal glider accidents and 36% of all glider fatalities have been due to stall/spin. That's 43 dead glider pilots and passengers, or slightly more than two per year. It is the leading cause of death while flying gliders. We must be doing something (or some things) wrong. My thought is if we are all aware that our perception from peripheral vision changes (and which way those changes work) we all may be in a slightly better position to resist the subconscious urge to do the wrong thing at just the wrong time.

9B

Mike the Strike

March 4th 14, 03:09 PM

On a recent landing at my home field, a potential conflict with another glider on final caused me to lengthen my base leg while I monitored the other plane. While checking the traffic, my airspeed dropped below my usual approach speed - I was watching the traffic and the field and not my panel or yaw string. I had to forcefully speed up before initiating my final turn.

I caught the problem early enough because I have a lot of time in the Discus 2 and it's a plane that behaves very well at low speed. However, I could easily see how a scenario like the one I experienced could result in a loss of control when the pilot is distracted from a normal pattern and landing..

Mike

[email protected]

March 4th 14, 03:57 PM

On Tuesday, March 4, 2014 6:43:31 AM UTC-8, wrote:
> On Tuesday, March 4, 2014 8:09:16 AM UTC-5, wrote:
>
> > On Tuesday, March 4, 2014 4:54:30 AM UTC-8, John Godfrey (QT) wrote: > On Tuesday, March 4, 2014 7:18:47 AM UTC-5, John Carlyle wrote: > > The insidious part is what you perceive in your peripheral vision unconsciously. True. Peripheral vision is terrible at detail but very good at picking up angular motion. Plus, last time I checked I was looking pretty close to down the wing as I initiated the turn from base to final. Aren't you supposed to look at the runway, not straight ahead into the countryside, on base leg? Once you're established on final there's not much turning anyway. 9B
>
>
>
> If you wait till you are wing is almost aligned with the runway, it is likely to be a bit late, commonly leading to a rushed, and possibly skidded turn.
>

Yup - I used "pretty close" as a qualifier. Your gaze is somewhere between down the wing and over the nose depending on the pattern. In any case it's likely the motion of the wing against the background will end up in your peripheral view.

Airspeed and coordination - it's only two items, yet so many people lose track of one or the other or both.

9B

John Carlyle

March 4th 14, 03:58 PM

I agree, there are multiple inputs to the pilot. The trick is prioritizing them and not getting distracted. I'm probably not any better at it than you; it's more likely that my instructors taught me somewhat differently.

On downwind I concentrate on airspeed, variometer rate, and traffic scan (I'll note the position of the runway as part of my traffic scan). When the runway disappears I'll wait an appropriate amount of time (judged from how fast I moved down the runway), take a quick look for traffic, runway position and turn roll out reference, and then (and only then) initiate my turn to base. During the 5 seconds I'm turning I'm looking directly forward over the nose, paying attention only to airspeed, yaw string and bank angle. The bank angle I always try to use is 45 degrees, while auxiliary inputs are slipstream noise, one or two glances at the ASI, the appearance of the rollout reference, and the imagined voice of my instructor chanting "airspeed, yaw string" over and over.

On the base leg I again concentrate on airspeed, variometer rate, and traffic scan (again noting the runway position as part of my traffic scan). At the appropriate position (judged from how fast the runway extended centerline is approaching, I initiate my turn to final. During the 5 seconds I'm turning I'm again looking directly forward over the nose, paying attention only to airspeed, yaw string and bank angle. Again the bank angle I always try to use is 45 degrees, while auxiliary inputs are slipstream noise, one or two glances at the ASI, the appearance of the runway, and the imagined voice of my instructor chanting "airspeed, yaw string" over and over.

Until a few months ago when I read about "pivot height" on this board, I had never known that the wing tip direction could reverse direction during a turn depending on your height. I assure you that's not from lack of experience on my part, it's just that I never look at the ground when I'm low and turning.

I also agree with you that the numbers of stall/spin accidents are appalling. As a community we need to try to reduce them. I just don't know if making people aware of peripheral vision changes is the way forward. Isn't it better to get them to focus only on what matters for the few seconds that are needed in a low altitude turn?

-John, Q3

On Tuesday, March 4, 2014 9:54:01 AM UTC-5, wrote:
> On Tuesday, March 4, 2014 5:34:09 AM UTC-8, John Carlyle wrote:
>
> > Just because you perceive something doesn't mean that you have to pay attention to it. The most important things in a pattern turn (or low altitude thermalling) are perfectly coordinated turns and proper airspeed. Scans for traffic and feeling for lift are fine, but who cares what the ground does?
>
> >
>
> > One does look at the airport when initiating the turn from base to final, but once the turn starts all you need to do for the next 5 seconds is look over the nose for pitch, yaw and bank. The airport will appear when you need it without having to search for it.
>
> >
>
> Well, it's a human in the loop feedback control system with multiple inputs - visual, inertial and some auditory. If you are making a low turn from base to final you may initiate the turn while looking away from the yaw string and airspeed because the runway is off to the side and you are trying to set a turn rate to put you in-line with the runway on final. At the same time your peripheral vision at this altitude is now subtly telling you that you are over-banked/under-ruddered because you are below the pivotal height where the turning cues of the wing against the background reverse. You aren't used to this peripheral cue and may not be aware of how it affects your overall perception of attitude and coordination and how that feeds back into the control system.
>
> You may be better at it than I am, but I can't just take a snapshot to the side before initiating the turn to final and then look ahead to the yaw string and airspeed without ever looking out to the runway again and expect to end up both pointed at and in-line with the runway heading. I tend to scan back and forth. It only takes a moment of being over-ruddered to generate a spin, particularly if you are at low speed (and an approach into an airport in a mountain valley can make you fly too nose-high if you are not paying proper attention).
>
> Is any of this good and proper airmanship - well no. But that is a little beside the point. The fact is that over the past 20 years 39% of fatal glider accidents and 36% of all glider fatalities have been due to stall/spin. That's 43 dead glider pilots and passengers, or slightly more than two per year. It is the leading cause of death while flying gliders. We must be doing something (or some things) wrong. My thought is if we are all aware that our perception from peripheral vision changes (and which way those changes work) we all may be in a slightly better position to resist the subconscious urge to do the wrong thing at just the wrong time.
>
> 9B

kirk.stant

March 4th 14, 04:54 PM

I wonder if part of the problem we have in patterns is the patterns themselves. Probably because of a military aviation background, I really (for both power and gliders) prefer the military continuous 180 turn from a lower closer downwind to final to the civilian higher, downwind - turn - base - turn - final approach.

I keep the pattern speed a bit high (say 60 - 65 knots in glass), half spoilers abeam the touchdown aimpoint, about 500' agl, pretty close in to the field, then at the TLAR point, roll into about 30 degrees of bank and turn in. If wide I can steepen up, if tight open out, but the turn is one continuous turn until rollout on final, and then I start transitioning to my final speed and adjusting to where I want to touch down.

Lower and closer in, I find it a lot easier to judge the angles; I HATE long finals!

So the turn is pretty much like any thermalling turn while adjusting the center, without having to roll completely in and out twice with the usual chance to under/over rudder the turn..

Just my 2 cents...

Kirk
66

[email protected]

March 4th 14, 05:00 PM

On Tuesday, March 4, 2014 10:58:56 AM UTC-5, John Carlyle wrote:
> I agree, there are multiple inputs to the pilot. The trick is prioritizing them and not getting distracted. I'm probably not any better at it than you; it's more likely that my instructors taught me somewhat differently. On downwind I concentrate on airspeed, variometer rate, and traffic scan (I'll note the position of the runway as part of my traffic scan). When the runway disappears I'll wait an appropriate amount of time (judged from how fast I moved down the runway), take a quick look for traffic, runway position and turn roll out reference, and then (and only then) initiate my turn to base. During the 5 seconds I'm turning I'm looking directly forward over the nose, paying attention only to airspeed, yaw string and bank angle. The bank angle I always try to use is 45 degrees, while auxiliary inputs are slipstream noise, one or two glances at the ASI, the appearance of the rollout reference, and the imagined voice of my instructor chanting "airspeed, yaw string" over and over. On the base leg I again concentrate on airspeed, variometer rate, and traffic scan (again noting the runway position as part of my traffic scan). At the appropriate position (judged from how fast the runway extended centerline is approaching, I initiate my turn to final. During the 5 seconds I'm turning I'm again looking directly forward over the nose, paying attention only to airspeed, yaw string and bank angle. Again the bank angle I always try to use is 45 degrees, while auxiliary inputs are slipstream noise, one or two glances at the ASI, the appearance of the runway, and the imagined voice of my instructor chanting "airspeed, yaw string" over and over. Until a few months ago when I read about "pivot height" on this board, I had never known that the wing tip direction could reverse direction during a turn depending on your height. I assure you that's not from lack of experience on my part, it's just that I never look at the ground when I'm low and turning. I also agree with you that the numbers of stall/spin accidents are appalling. As a community we need to try to reduce them. I just don't know if making people aware of peripheral vision changes is the way forward. Isn't it better to get them to focus only on what matters for the few seconds that are needed in a low altitude turn? -John, Q3 On Tuesday, March 4, 2014 9:54:01 AM UTC-5, wrote: > On Tuesday, March 4, 2014 5:34:09 AM UTC-8, John Carlyle wrote: > > > Just because you perceive something doesn't mean that you have to pay attention to it. The most important things in a pattern turn (or low altitude thermalling) are perfectly coordinated turns and proper airspeed. Scans for traffic and feeling for lift are fine, but who cares what the ground does? > > > > > > One does look at the airport when initiating the turn from base to final, but once the turn starts all you need to do for the next 5 seconds is look over the nose for pitch, yaw and bank. The airport will appear when you need it without having to search for it. > > > > > Well, it's a human in the loop feedback control system with multiple inputs - visual, inertial and some auditory. If you are making a low turn from base to final you may initiate the turn while looking away from the yaw string and airspeed because the runway is off to the side and you are trying to set a turn rate to put you in-line with the runway on final. At the same time your peripheral vision at this altitude is now subtly telling you that you are over-banked/under-ruddered because you are below the pivotal height where the turning cues of the wing against the background reverse. You aren't used to this peripheral cue and may not be aware of how it affects your overall perception of attitude and coordination and how that feeds back into the control system. > > You may be better at it than I am, but I can't just take a snapshot to the side before initiating the turn to final and then look ahead to the yaw string and airspeed without ever looking out to the runway again and expect to end up both pointed at and in-line with the runway heading. I tend to scan back and forth. It only takes a moment of being over-ruddered to generate a spin, particularly if you are at low speed (and an approach into an airport in a mountain valley can make you fly too nose-high if you are not paying proper attention). > > Is any of this good and proper airmanship - well no. But that is a little beside the point. The fact is that over the past 20 years 39% of fatal glider accidents and 36% of all glider fatalities have been due to stall/spin. That's 43 dead glider pilots and passengers, or slightly more than two per year. It is the leading cause of death while flying gliders. We must be doing something (or some things) wrong. My thought is if we are all aware that our perception from peripheral vision changes (and which way those changes work) we all may be in a slightly better position to resist the subconscious urge to do the wrong thing at just the wrong time. > > 9B

I get a bit concerned about the term "concentrate", that implies to me, the exclusion of information. Any time one narrows the focus the opportunity to get and process potentially valuable information is lost. I see many pilots "concentrate" on the runway or touchdown point to the exclusion of other valuable information such as attitude, airspeed, and coordination. Maybe Q3 is using too strong a word for what he does.
UH

Bob Whelan[_3_]

March 4th 14, 05:22 PM

> Airspeed and coordination - it's only two items, yet so many people lose
> track of one or the other or both.

Great, thought-provoking, thread, with excellent points-n-perspectives all
around. And though I doubt what's below will add anything not already noted,
repetition is often useful in learning...

I flew gliders (only) for more than a decade before learning of "pivotal
altitude" (from an article in "Soaring" magazine as I recall). By then,
reading had also alerted me to a whole bunch of other not-then-experienced
optical illusions and "altered visual perspectives" pilots could encounter.
Meanwhile, I'd been flying successfully enough I'd not yet (or to-date) come
even vaguely close to an unexpected departure from controlled flight in the
landing pattern, despite "the usual number" of off-field landings by then.

Yet by the time I became aware of "pivotal altitude" I knew of dead pilots -
soaring and otherwise - who evidently HAD experienced unexpected departures
from controlled flight in landing patterns (mostly at airports), including
some with gobs more time than I. My conclusion? Clearly, failure to pay
attention to and control airspeed and coordination (neither being more
important than the other, IMO) - as noted above - could easily be my last mistake.

The $64,000 question is: How can a person "become immune" from making the
mistake(s) in the landing pattern that lead to NOT always being able to
effectively monitor/control airspeed & coordination in the pattern?

IMO, education is good. (Duh!) And given the complex differences among humans,
the idea of making students aware of all known possible distractions (visual
and otherwise) in landing patterns is probably a good instructional thing, and
- clearly - conveying in practical terms the "look and feel" of pivotal
altitude cannot be done in a sailplane. So if you're one of the lucky ones who
can always monitor and effectively control airspeed and coordination in your
landing patterns, then probably no need for power-plane exposure to pivotal
altitude. But for anyone uncertain of their capabilities...maybe it'd be a
great idea to go get some personal exposure with a power instructor you're
certain is knowledgeable of - and confident about their ability to safely
teach - the concept. For I suspect not all instructors ARE safely qualified to
expose students to the pivotal altitude concept. (I hope I'm wrong, but when
it's my life at stake, I tend to be conservative! :-) )

Bob W.

John Carlyle

March 4th 14, 05:35 PM

How about "concentrate by prioritizing tasks and not getting distracted while not developing tunnel vision"? <grin> I do get your point, and it's valuable.

-John, Q3

On Tuesday, March 4, 2014 12:00:44 PM UTC-5, wrote:
> I get a bit concerned about the term "concentrate", that implies to me, the exclusion of information. Any time one narrows the focus the opportunity to get and process potentially valuable information is lost. I see many pilots "concentrate" on the runway or touchdown point to the exclusion of other valuable information such as attitude, airspeed, and coordination. Maybe Q3 is using too strong a word for what he does.
>
> UH

Bob Whelan[_3_]

March 4th 14, 05:38 PM

On 3/4/2014 9:54 AM, kirk.stant wrote:
> I wonder if part of the problem we have in patterns is the patterns
> themselves. Probably because of a military aviation background, I really
> (for both power and gliders) prefer the military continuous 180 turn from a
> lower closer downwind to final to the civilian higher, downwind - turn -
> base - turn - final approach.
>
> I keep the pattern speed a bit high (say 60 - 65 knots in glass), half
> spoilers abeam the touchdown aimpoint, about 500' agl, pretty close in to
> the field, then at the TLAR point, roll into about 30 degrees of bank and
> turn in. If wide I can steepen up, if tight open out, but the turn is one
> continuous turn until rollout on final, and then I start transitioning to
> my final speed and adjusting to where I want to touch down.
>
> Lower and closer in, I find it a lot easier to judge the angles; I HATE
> long finals!
>
> So the turn is pretty much like any thermalling turn while adjusting the
> center, without having to roll completely in and out twice with the usual
> chance to under/over rudder the turn..
>
> Just my 2 cents...
>
> Kirk 66

FWIW...

Way back when I had about 200 total hours, all glider, I flew an HP-14 from a
busy municipal airport with 3 closely-spaced parallel runways. SOP traffic
separation had gliders flying a 4-sided pattern entered from midfield, the
downwind, base and final legs being inside the same-turning-direction power
pattern, which normally used the southernmost E-W runway.

Schreder's original HP-14 design wasn't noted for being a rapid roller. While
it WAS possible to fly a rectangular pattern in it inside the power pattern,
doing so required serious (both arms essentially required) stick effort to
achieve max aileron deflection on the final-to-base and base-to-final turns,
to the point I found doing so a mental distraction...and thus less than
"ideally safe."

I found "a circling approach" (a la the U.S. Navy) from downwind to final
considerably easier - and a no-brainer, as Kirk suggests above - to implement.
A circling approach quickly became my standard procedure in that ship at that
airport.

When people asked, I told 'em why. Few asked.

Bob W.

Dan Marotta

March 4th 14, 05:45 PM

I'm looking at aim point and clearing final for that Cessna on a straight-in
who didn't use his radio... No need to look at the ground - I know it's
still there.

"John Carlyle" > wrote in message
...
Who looks down the wing at the ground when they turn? In pattern turns I'm
looking straight over the glare shield, focused on airspeed (pitch), yaw
string, and bank angle.

-John, Q3

On Monday, March 3, 2014 10:54:39 PM UTC-5, Bill D wrote:
> The argument which says one should avoid low turns ignores the fact that
> every glider flight ends with at least one turn at or below 300' AGL.
> Unless a pilot is well trained for low turns this is a recipe for a
> stall/spin accident. I respectively suggest a better alternative is to
> find a CFI willing to provide GRM training in a touring motorglider or
> slow LSA and get really good at it.

John Carlyle

March 4th 14, 05:47 PM

I know someone who flies the pattern as you describe; he had flown F-4's onto carriers. My instructor told me he felt it was safer to separate tasks in the pattern rather than combine them. So I do it his way...

-John, Q3

On Tuesday, March 4, 2014 11:54:37 AM UTC-5, kirk.stant wrote:
> I wonder if part of the problem we have in patterns is the patterns themselves. Probably because of a military aviation background, I really (for both power and gliders) prefer the military continuous 180 turn from a lower closer downwind to final to the civilian higher, downwind - turn - base - turn - final approach.
>
> I keep the pattern speed a bit high (say 60 - 65 knots in glass), half spoilers abeam the touchdown aimpoint, about 500' agl, pretty close in to the field, then at the TLAR point, roll into about 30 degrees of bank and turn in. If wide I can steepen up, if tight open out, but the turn is one continuous turn until rollout on final, and then I start transitioning to my final speed and adjusting to where I want to touch down.
>
> Lower and closer in, I find it a lot easier to judge the angles; I HATE long finals!
>
> So the turn is pretty much like any thermalling turn while adjusting the center, without having to roll completely in and out twice with the usual chance to under/over rudder the turn..
>
> Just my 2 cents...
>
> Kirk
> 66

Dan Marotta

March 4th 14, 05:59 PM

I fly my pattern just like Kirk, though a little higher and faster at the
start. I begin my descending final turn when abeam the touchdown point and
roll out on final at about 200 ft and over the numbers. I do this both in
my LAK and in the tow planes.

I did it this way in the Air Force and when I flew a King Air for
FlightSafety. The only exception was in the B-727. Gotta be gentle for the
pax.

"kirk.stant" > wrote in message
...
I wonder if part of the problem we have in patterns is the patterns
themselves. Probably because of a military aviation background, I really
(for both power and gliders) prefer the military continuous 180 turn from a
lower closer downwind to final to the civilian higher, downwind - turn -
base - turn - final approach.

I keep the pattern speed a bit high (say 60 - 65 knots in glass), half
spoilers abeam the touchdown aimpoint, about 500' agl, pretty close in to
the field, then at the TLAR point, roll into about 30 degrees of bank and
turn in. If wide I can steepen up, if tight open out, but the turn is one
continuous turn until rollout on final, and then I start transitioning to my
final speed and adjusting to where I want to touch down.

Lower and closer in, I find it a lot easier to judge the angles; I HATE long
finals!

So the turn is pretty much like any thermalling turn while adjusting the
center, without having to roll completely in and out twice with the usual
chance to under/over rudder the turn..

Just my 2 cents...

Kirk
66

son_of_flubber

March 4th 14, 06:13 PM

Why are pilots so committed to the idea that they can reliably judge airspeed by looking at the sight picture over the nose? What if the runway tilts up and it is surrounded by hills and trees?

The only time that I bet my life on the sight picture is when I'm on a steep final, I'm holding the air brake at a constant setting, and I'm sure that the glide angle and the touchdown point are stable and unchanging.

John Carlyle

March 4th 14, 06:23 PM

In my very short 8 years of glider only flight I've witnessed 4 pattern mishaps (no fatalities, fortunately). Two happened because the pilots wouldn't truncate their patterns even though they could see that they were way too low, one happened because an instructor pulled the release too low, and the last happened because I believed my altimeter when it said I was too high (I'd set it wrong and wasn't fully versed in TLAR). Fortunately I didn't damage either myself or the glider, but the incipient low altitude stall I experienced that day is something I'll never forget.

Is it possible to "become immune" from making mistakes in the pattern. I don't think so. All you can do is to give your full attention to flying the airplane properly. Prioritize tasks for different phases of the pattern and try your very best to execute them perfectly.

-John, Q3

On Tuesday, March 4, 2014 12:22:39 PM UTC-5, Bob Whelan wrote:
> I flew gliders (only) for more than a decade before learning of "pivotal
> altitude" (from an article in "Soaring" magazine as I recall). By then,
> reading had also alerted me to a whole bunch of other not-then-experienced
> optical illusions and "altered visual perspectives" pilots could encounter.
>
> Meanwhile, I'd been flying successfully enough I'd not yet (or to-date) come
> even vaguely close to an unexpected departure from controlled flight in the
> landing pattern, despite "the usual number" of off-field landings by then..
>
> Yet by the time I became aware of "pivotal altitude" I knew of dead pilots -
> soaring and otherwise - who evidently HAD experienced unexpected departures
> from controlled flight in landing patterns (mostly at airports), including
> some with gobs more time than I. My conclusion? Clearly, failure to pay
> attention to and control airspeed and coordination (neither being more
> important than the other, IMO) - as noted above - could easily be my last mistake.
>
> The $64,000 question is: How can a person "become immune" from making the
> mistake(s) in the landing pattern that lead to NOT always being able to
> effectively monitor/control airspeed & coordination in the pattern?
>
> IMO, education is good. (Duh!) And given the complex differences among humans,
> the idea of making students aware of all known possible distractions (visual
> and otherwise) in landing patterns is probably a good instructional thing, and
> - clearly - conveying in practical terms the "look and feel" of pivotal
> altitude cannot be done in a sailplane. So if you're one of the lucky ones who
> can always monitor and effectively control airspeed and coordination in your
> landing patterns, then probably no need for power-plane exposure to pivotal
=> altitude. But for anyone uncertain of their capabilities...maybe it'd be a
> great idea to go get some personal exposure with a power instructor you're
> certain is knowledgeable of - and confident about their ability to safely
> teach - the concept. For I suspect not all instructors ARE safely qualified to
> expose students to the pivotal altitude concept. (I hope I'm wrong, but when
> it's my life at stake, I tend to be conservative! :-) )
>
> Bob W.

Jim White[_3_]

March 4th 14, 06:24 PM

I must be at risk! As I think and do it a bit differently to most here.

In the circuit I trim for landing speed c. 50% above stall speed + c. half
the headwind speed. In still air in my 27 this is 52kts and in a gale it
could be 70 or 80kts. Fast is good unless in something like a Duo going
into a small field!

In the UK we are taught not to fly a square circuit, we lop off the
downwind corner to keep us closer to the airfield (less downwind) and keep
the landing area and reference point in view. This tends to induce a
curving base leg anyway.

I aim to get at the final turn between 300ft and higher if windy and I put
in a steeply banked final turn. The steeper the bank the harder it is to
over rudder into a spin. Probably impossible at 45 or more - Chris Rollings
would know. It is also much harder to stall requiring a lot of elevator.

From the point of starting my final turn to landing I am pretty much
focussed only on the reference point and the airspeed. Keep the airspeed
pegged and use the brake to arrive in the right place.

This close to the ground it is pretty obvious if you are slipping, which
could of course be intentional. If you are side slipping on purpose you
probably don't have enough elevator to stall.

Should I give up before I kill myself?

John Carlyle

March 4th 14, 06:30 PM

If this is in response to one of my posts, you missed the bit where I said "...auxiliary inputs are slipstream noise, one or two glances at the ASI..."

-John, Q3

On Tuesday, March 4, 2014 1:13:49 PM UTC-5, son_of_flubber wrote:
> Why are pilots so committed to the idea that they can reliably judge airspeed by looking at the sight picture over the nose? What if the runway tilts up and it is surrounded by hills and trees?

[email protected]

March 4th 14, 06:36 PM

On Tuesday, March 4, 2014 1:13:49 PM UTC-5, son_of_flubber wrote:
> Why are pilots so committed to the idea that they can reliably judge airspeed by looking at the sight picture over the nose? What if the runway tilts up and it is surrounded by hills and trees? The only time that I bet my life on the sight picture is when I'm on a steep final, I'm holding the air brake at a constant setting, and I'm sure that the glide angle and the touchdown point are stable and unchanging.

It is not the sight picture itself, it is the change in the sight picture that needs to be noticed.
If you are staring at the wing tip. or the landing target, you likley aren't noticing that you pulled the nose up in the turn or were skidding. Obviously terrain affects the sight picture.
When looking at the nose, a quick eye movement allows the airspeed to be checked for confirmation.
UH

Bob Whelan[_3_]

March 4th 14, 07:11 PM

On 3/4/2014 11:23 AM, John Carlyle wrote:
<Snip...>
> Is it possible to "become immune" from making mistakes in the pattern. I
> don't think so. All you can do is to give your full attention to flying the
> airplane properly. Prioritize tasks for different phases of the pattern and
> try your very best to execute them perfectly.
>
> -John, Q3

Yup!

>
> On Tuesday, March 4, 2014 12:22:39 PM UTC-5, Bob Whelan wrote:
<Snip...>
>> The $64,000 question is: How can a person "become immune" from making
>> the mistake(s) in the landing pattern that lead to NOT always being able
>> to effectively monitor/control airspeed & coordination in the pattern?

We agree on the impossibility of "becom[ing] immune" from making mistakes in
the pattern (or anywhere else/hence my original quotes). Human perfection
isn't an option.

In addition to that assumption, another of my operating assumptions is an
assumed life-critical need for continual monitoring of "things" crucial to
continuing achievement of my intentions...in this case not departing from
controlled flight in the landing pattern.

Goal (see next paragraph) achieved by: pilot control inputs (required to
achieve goal); monitoring of flight conditions/path; corrective feedback loop
to control inputs. Continue circularly until a new goal can be set and begun
acting upon...

In every landing pattern, my unchanging Primary Goal is to land safely,
without hitting anything other than mother earth - in the intended manner and
near some specifically selected desired location - with appropriate
amount/vectors of kinetic energy. Personally, I think that ought to be the
goal of every pilot's landing patterns. :-)

However Joe Pilot achieves that goal is inextricably linked with how their
brain works, hence the potential value of these sorts of brain-engaging
discussions, in my view...

Bob W.

John Carlyle

March 4th 14, 07:46 PM

Very good point, Bob (how their brain works). I know that there are many ways to accomplish almost everything, but as an engineer I know that only a few are "safe" and/or "efficient" and usually only one is "elegant". What fascinates me is watching someone else solving the same problem and seeing things they come up with that I never thought of...

-John, Q3

On Tuesday, March 4, 2014 2:11:00 PM UTC-5, Bob Whelan wrote:
> In every landing pattern, my unchanging Primary Goal is to land safely,
> without hitting anything other than mother earth - in the intended manner and
> near some specifically selected desired location - with appropriate
> amount/vectors of kinetic energy. Personally, I think that ought to be the
> goal of every pilot's landing patterns. :-)
>
> However Joe Pilot achieves that goal is inextricably linked with how their
> brain works, hence the potential value of these sorts of brain-engaging
> discussions, in my view...
>
> Bob W.

son_of_flubber

March 5th 14, 12:11 AM

On Tuesday, March 4, 2014 1:30:34 PM UTC-5, John Carlyle wrote:
> If this is in response to one of my posts,

Not particularly your post. Many pilots are committed to the primacy of the sight picture at turn to final.

JC wrote:
>you missed the bit where I said "...AUXILIARY (ed. caps) inputs are slipstream noise, one or two glances at the ASI..."
>

My take is that just before entering the turn to final, slipstream noise and ASI (and yaw string) are PRIMARY reliable inputs, and that point sight picture is an unreliable input that is subject to pilot error and visual illusions.

As I got better over time at using the sight picture to estimate pattern speed, I found myself relying on it more and more. My tendency to discount and neglect the primary reliable inputs made me more dangerous.

Dan Marotta

March 5th 14, 12:45 AM

It's not just the view, though with experience you get to recognize rates of
change, there's also sound and control feel. But I think everyone
(including myself) steals the occasional peek at the airspeed indicator as
well.

"son_of_flubber" > wrote in message
...
> Why are pilots so committed to the idea that they can reliably judge
> airspeed by looking at the sight picture over the nose? What if the runway
> tilts up and it is surrounded by hills and trees?
>
> The only time that I bet my life on the sight picture is when I'm on a
> steep final, I'm holding the air brake at a constant setting, and I'm sure
> that the glide angle and the touchdown point are stable and unchanging.

Bill D

March 5th 14, 03:18 AM

On Tuesday, March 4, 2014 5:11:02 PM UTC-7, son_of_flubber wrote:
> On Tuesday, March 4, 2014 1:30:34 PM UTC-5, John Carlyle wrote:
>
> > If this is in response to one of my posts,
>
>
>
> Not particularly your post. Many pilots are committed to the primacy of the sight picture at turn to final.
>
>
>
> JC wrote:
>
> >you missed the bit where I said "...AUXILIARY (ed. caps) inputs are slipstream noise, one or two glances at the ASI..."
>
> >
>
>
>
> My take is that just before entering the turn to final, slipstream noise and ASI (and yaw string) are PRIMARY reliable inputs, and that point sight picture is an unreliable input that is subject to pilot error and visual illusions.
>
>
>
> As I got better over time at using the sight picture to estimate pattern speed, I found myself relying on it more and more. My tendency to discount and neglect the primary reliable inputs made me more dangerous.

At low altitude and certainly in mountainous country, the "sight picture" is unreliable. (If your destination airport is in a deep "V" valley, at which rock or tree do you point the nose?) As other posters noted, at low altitude, the apparent horizon seems high so the nose appears too low even when it right. So what does one watch? The answer is a fast repetitive scan of everything. Keep coming back to the airspeed and yaw string every few seconds to note trends but don't linger there more than a second or two.

One important action is to trim the glider so it will tend to remain at the desired pattern airspeed. Sergio's article in the February Soaring where he describes pushing the stick without effect struck me as perfect description of a mis-trimmed glider. If trimmed correctly, just relaxing pressure on the stick will cause a too-high nose to lower itself - you don't have to push.

In fact, teaching pilots to fly with a relaxed grip instead of a "death-grip" on the stick would probably in itself eliminate many stall/spin accidents. A well trimmed glider simply won't spin itself - it takes gross control inputs to make it spin which is more difficult to do with finger tip pressure.

Another very useful skill is semi-instrument flying - controlling pitch attitude with airspeed alone. (It's the airspeed part of "needle, ball airspeed" partial-panel instrument flying.) This involves watching the airspeed trend. If it's trending lower, the nose is too high and if trending higher, the nose is too low. This is something that can be learned in an airplane while doing ground reference maneuvers.

John Carlyle

March 5th 14, 01:35 PM

Dan,

Would you do a circling approach if you were going into a difficult strip, too? Say, a narrow cornfield surrounded by trees. I ask because the Navy pilots I know who fly gliders have reverted to the non-circling approach.

-John, Q3

On Tuesday, March 4, 2014 12:59:10 PM UTC-5, Dan Marotta wrote:
> I fly my pattern just like Kirk, though a little higher and faster at the
> start. I begin my descending final turn when abeam the touchdown point and
> roll out on final at about 200 ft and over the numbers. I do this both in
> my LAK and in the tow planes.
>
> I did it this way in the Air Force and when I flew a King Air for
> FlightSafety. The only exception was in the B-727. Gotta be gentle for the
> pax.

Dan Marotta

March 5th 14, 04:10 PM

John,

Yes, I would. It's the pattern I've flown for 40+ years and it's always
worked well for me. I would not consider changing to a square base with a
90 degree turn to final during a critical outlanding at a fenced field.
Likewise, I wouldn't advise anyone to switch to a circling landing under the
same circumstances.

I plan my patterns to roll to a stop at the same location every time using
minimal wheel brake. I do this with calm winds and 30+ kt winds. I find it
easier to plan and execute simply by changing the point where I begin my
final turn.

PS - Navy pilots can't land, then only crash and hope the wire stops them
before they go over the side. ;-)

"John Carlyle" > wrote in message
...
> Dan,
>
> Would you do a circling approach if you were going into a difficult strip,
> too? Say, a narrow cornfield surrounded by trees. I ask because the Navy
> pilots I know who fly gliders have reverted to the non-circling approach.
>
> -John, Q3
>
> On Tuesday, March 4, 2014 12:59:10 PM UTC-5, Dan Marotta wrote:
>> I fly my pattern just like Kirk, though a little higher and faster at the
>> start. I begin my descending final turn when abeam the touchdown point
>> and
>> roll out on final at about 200 ft and over the numbers. I do this both
>> in
>> my LAK and in the tow planes.
>>
>> I did it this way in the Air Force and when I flew a King Air for
>> FlightSafety. The only exception was in the B-727. Gotta be gentle for
>> the
>> pax.

John Carlyle

March 5th 14, 04:20 PM

Thanks, Dan. I suspected you'd keep on with what was familiar to you.

-John, Q3

PS - My Navy buddies tell me they do circling approaches because the airstrip is moving. Air Force pilots copy Navy pilots because the field knows an Air Force pilot is coming and it will run away... <grin>

On Wednesday, March 5, 2014 11:10:00 AM UTC-5, Dan Marotta wrote:
> John,
>
> Yes, I would. It's the pattern I've flown for 40+ years and it's always
> worked well for me. I would not consider changing to a square base with a
> 90 degree turn to final during a critical outlanding at a fenced field.
> Likewise, I wouldn't advise anyone to switch to a circling landing under the
> same circumstances.
>
> I plan my patterns to roll to a stop at the same location every time using
> minimal wheel brake. I do this with calm winds and 30+ kt winds. I find it
> easier to plan and execute simply by changing the point where I begin my
> final turn.
>
> PS - Navy pilots can't land, then only crash and hope the wire stops them
> before they go over the side. ;-)
>
> "John Carlyle" > wrote in message
> ...
> > Dan,
> >
> > Would you do a circling approach if you were going into a difficult strip,
> > too? Say, a narrow cornfield surrounded by trees. I ask because the Navy
> > pilots I know who fly gliders have reverted to the non-circling approach.
> >
> > -John, Q3
> >
>
> > On Tuesday, March 4, 2014 12:59:10 PM UTC-5, Dan Marotta wrote:
>
> >> I fly my pattern just like Kirk, though a little higher and faster at the
>
> >> start. I begin my descending final turn when abeam the touchdown point
>
> >> and
>
> >> roll out on final at about 200 ft and over the numbers. I do this both
>
> >> in
>
> >> my LAK and in the tow planes.
>
> >>
>
> >> I did it this way in the Air Force and when I flew a King Air for
>
> >> FlightSafety. The only exception was in the B-727. Gotta be gentle for
>
> >> the
>
> >> pax.

kirk.stant

March 5th 14, 04:30 PM

On Wednesday, March 5, 2014 7:35:51 AM UTC-6, John Carlyle wrote:

> Would you do a circling approach if you were going into a difficult strip, too? Say, a narrow cornfield surrounded by trees. I ask because the Navy pilots I know who fly gliders have reverted to the non-circling approach.

Depends. If low, yes - I'll fly whatever pattern I can to land safely. If I have more time and want to look over the landing area more, then I might fly a higher, longer pattern to give more time to pick the best place to land. Also need to be able to fly bigger patterns when sequencing behind other gliders, so all the skills need to be maintained.

I think it's important to be able to fly a "de-stabilized" (non-constant airspeed) approach in gliders, so that energy can be maintained until late in the approach, and used or gotten rid of as required. Also should be able to fly an approach from just about anywhere around the intended point of landing. Always flying the same pattern into the same airfield pretty much guarantees that your first landout will be exciting! Power pilots are taught to fly "stabilized approaches" because that is how you land a big airplane.. Totally unnecessary in small planes, and IMO downright dangerous in gliders.

As far as watching the ASI, after reaching the TLAR point where I want to start the turn, I look just to the inside (11 or 1 o'clock) when initiating the turn, monitor the ASI for trend (glider is trimmed slightly fast), monitor the yawstring, then check how the turn is progressing, then back to ASI - yawstring - turn, etc until time to roll out. If it's a busy runway I might roll out momentarily to check the extended final, then roll back into the turn - those would be pretty aggressive rolls with lots of speed.

Kirk

John Carlyle

March 5th 14, 06:08 PM

Kirk,

Thank for writing that - very interesting that you mix approach types.

I'm not too clear about your comment "always flying the same pattern into the same airfield pretty much guarantees that your first landout will be exciting". I always use a downwind-base-final pattern, I've logged 10 landouts in farmers fields, and except for having to dodge an electric wire fence once they were low or no drama events (although some of the retrieves were interesting).

Your "de-stabilized" (non-constant airspeed) approach comment was also interesting. I tend to keep high until on final, just to keep my options open, but my speed stays pretty much constant. Being high has helped me on several occasions to delay a bit (once a person behind me with no radio landed under me, another time someone drove onto the field). Do I understand correctly that you tend to keep your energy in speed rather than altitude?

-John, Q3

On Wednesday, March 5, 2014 11:30:30 AM UTC-5, kirk.stant wrote:
> On Wednesday, March 5, 2014 7:35:51 AM UTC-6, John Carlyle wrote:
>
> > Would you do a circling approach if you were going into a difficult strip, too? Say, a narrow cornfield surrounded by trees. I ask because the Navy pilots I know who fly gliders have reverted to the non-circling approach.
>
> Depends. If low, yes - I'll fly whatever pattern I can to land safely. If I have more time and want to look over the landing area more, then I might fly a higher, longer pattern to give more time to pick the best place to land. Also need to be able to fly bigger patterns when sequencing behind other gliders, so all the skills need to be maintained.
>
> I think it's important to be able to fly a "de-stabilized" (non-constant airspeed) approach in gliders, so that energy can be maintained until late in the approach, and used or gotten rid of as required. Also should be able to fly an approach from just about anywhere around the intended point of landing. Always flying the same pattern into the same airfield pretty much guarantees that your first landout will be exciting! Power pilots are taught to fly "stabilized approaches" because that is how you land a big airplane. Totally unnecessary in small planes, and IMO downright dangerous in gliders.
>
> As far as watching the ASI, after reaching the TLAR point where I want to start the turn, I look just to the inside (11 or 1 o'clock) when initiating the turn, monitor the ASI for trend (glider is trimmed slightly fast), monitor the yawstring, then check how the turn is progressing, then back to ASI - yawstring - turn, etc until time to roll out. If it's a busy runway I might roll out momentarily to check the extended final, then roll back into the turn - those would be pretty aggressive rolls with lots of speed.
>
> Kirk

[email protected]

March 5th 14, 08:24 PM

On Tuesday, March 4, 2014 7:58:56 AM UTC-8, John Carlyle wrote:

I just don't know if making people aware of peripheral vision changes is the way forward. Isn't it better to get them to focus only on what matters for the few seconds that are needed in a low altitude turn?

Visual perception is certainly not the only thing. I do think it is how most pilots interpolate between references to the airspeed and yaw string. Generally that scan cycle is a pretty rapid loop and wandering into stall/spin is not a big risk. I do believe that pilots get into trouble because, for one reason or another, they: 1) don't update the scan, 2) misinterpret what the instruments are telling them or 3) fail to act. I'd bet that #1 is the main thing - possibly due to distraction, fixation, overload or other reasons. When this happens your central and peripheral vision (and your inner ear) are how you maintain attitude and airspeed and that can drift, but also can be fooled if the visual cues are different than what you get 99% of the time when you are flying above a couple hundred feet. Why is this important to know? Because if you know and train to recognize that the cues will push to towards a skidding turn that is too slow you have a better chance of checking yourself before you do something based on instincts honed by flying at altitude that down low can kill you.

I do not know how strong these effects are but a ride with a competent check pilot/instructor might be able to inform how strong the tendency is.

That's my theory anyway.

9B

[email protected]

March 5th 14, 08:33 PM

On Wednesday, March 5, 2014 12:24:51 PM UTC-8, wrote:
> On Tuesday, March 4, 2014 7:58:56 AM UTC-8, John Carlyle wrote:

> Visual perception is certainly not the only thing. I do think it is how most pilots interpolate between references to the airspeed and yaw string. Generally that scan cycle is a pretty rapid loop and wandering into stall/spin is not a big risk. I do believe that pilots get into trouble because, for one reason or another, they: 1) don't update the scan, 2) misinterpret what the instruments are telling them or 3) fail to act. I'd bet that #1 is the main thing - possibly due to distraction, fixation, overload or other reasons. When this happens your central and peripheral vision (and your inner ear) are how you maintain attitude and airspeed and that can drift, but also can be fooled if the visual cues are different than what you get 99% of the time when you are flying above a couple hundred feet. Why is this important to know? Because if you know and train to recognize that the cues will push to towards a skidding turn that is too slow you have a better chance of checking yourself before you do something based on instincts honed by flying at altitude that down low can kill you.
>
> I do not know how strong these effects are but a ride with a competent check pilot/instructor might be able to inform how strong the tendency is.
>
> That's my theory anyway.
>
> 9B

BTW, that's one reason why I tend to carry a bit more airspeed until I'm on final (like Kirk). I know that if I get a surprise or distraction on the turn to final with a bigger speed margin I will have more time to sort the distraction before airspeed bleeds off. That works in my -27. I don't do it in a Duo.

9B

John Firth[_4_]

March 5th 14, 08:37 PM

Always check for that low airplane dragging it in on a long final.
JMF

At 18:08 05 March 2014, John Carlyle wrote:
>Kirk,
>
>Thank for writing that - very interesting that you mix approach types.=20
>
>I'm not too clear about your comment "always flying the same pattern into
>t=
>he same airfield pretty much guarantees that your first landout will be
>exc=
>iting". I always use a downwind-base-final pattern, I've logged 10
>landouts=
> in farmers fields, and except for having to dodge an electric wire fence
>o=
>nce they were low or no drama events (although some of the retrieves were
>i=
>nteresting).=20
>
>Your "de-stabilized" (non-constant airspeed) approach comment was also
>inte=
>resting. I tend to keep high until on final, just to keep my options
open,
>=
>but my speed stays pretty much constant. Being high has helped me on
>severa=
>l occasions to delay a bit (once a person behind me with no radio landed
>un=
>der me, another time someone drove onto the field). Do I understand
>correct=
>ly that you tend to keep your energy in speed rather than altitude?=20
>
>-John, Q3
>
>On Wednesday, March 5, 2014 11:30:30 AM UTC-5, kirk.stant wrote:
>> On Wednesday, March 5, 2014 7:35:51 AM UTC-6, John Carlyle wrote:
>>=20
>> > Would you do a circling approach if you were going into a difficult
>str=
>ip, too? Say, a narrow cornfield surrounded by trees. I ask because the
>Nav=
>y pilots I know who fly gliders have reverted to the non-circling
>approach.=
>=20
>>=20
>> Depends. If low, yes - I'll fly whatever pattern I can to land safely.
>I=
>f I have more time and want to look over the landing area more, then I
>migh=
>t fly a higher, longer pattern to give more time to pick the best place
to
>=
>land. Also need to be able to fly bigger patterns when sequencing behind
>ot=
>her gliders, so all the skills need to be maintained.
>>=20
>> I think it's important to be able to fly a "de-stabilized"
(non-constant
>=
>airspeed) approach in gliders, so that energy can be maintained until
late
>=
>in the approach, and used or gotten rid of as required. Also should be
>able=
> to fly an approach from just about anywhere around the intended point of
>l=
>anding. Always flying the same pattern into the same airfield pretty
much
>=
>guarantees that your first landout will be exciting! Power pilots are
>taug=
>ht to fly "stabilized approaches" because that is how you land a big
>airpla=
>ne. Totally unnecessary in small planes, and IMO downright dangerous in
>gl=
>iders.
>>=20
>> As far as watching the ASI, after reaching the TLAR point where I want
>to=
> start the turn, I look just to the inside (11 or 1 o'clock) when
>initiatin=
>g the turn, monitor the ASI for trend (glider is trimmed slightly fast),
>mo=
>nitor the yawstring, then check how the turn is progressing, then back to
>A=
>SI - yawstring - turn, etc until time to roll out. If it's a busy runway
>I=
> might roll out momentarily to check the extended final, then roll back
>int=
>o the turn - those would be pretty aggressive rolls with lots of speed.
>>=20
>> Kirk
>
>

John Carlyle

March 5th 14, 09:53 PM

Agree with your three points of how pilots get into trouble. I also agree that training is important, and that it's never a bad idea to take a ride with an instructor.

I'm not sure I buy your theory of an optical illusion in your peripheral vision causing your central vision and inner ear to start giving you bad data, though. It takes time (probably a minute) without good visual cues for your inner ear to start disconnecting from reality. Your central vision looking over the nose will provide good feedback to your inner ear even if there is a peripheral mirage, so I think your balance and motion sensation will remain OK.

That said, I can understand someone deciding to focus with central vision on something seen peripherally, but unless they decide to fixate on it (thus causing your errors 1 and 3) I don't see it as a problem because if you look over the nose again you'll perceive that you're OK. Thus my comment many messages before that "Just because you perceive something doesn't mean that you have to pay attention to it".

Perhaps you and I should take rides with instructors this spring, see if wing motion reversal down low causes either of us problems, and then compare notes.

-John, Q3

On Wednesday, March 5, 2014 3:33:08 PM UTC-5, wrote:
> On Wednesday, March 5, 2014 12:24:51 PM UTC-8, wrote:
> > Visual perception is certainly not the only thing. I do think it is how most pilots interpolate between references to the airspeed and yaw string.. Generally that scan cycle is a pretty rapid loop and wandering into stall/spin is not a big risk. I do believe that pilots get into trouble because, for one reason or another, they: 1) don't update the scan, 2) misinterpret what the instruments are telling them or 3) fail to act. I'd bet that #1 is the main thing - possibly due to distraction, fixation, overload or other reasons. When this happens your central and peripheral vision (and your inner ear) are how you maintain attitude and airspeed and that can drift, but also can be fooled if the visual cues are different than what you get 99% of the time when you are flying above a couple hundred feet. Why is this important to know? Because if you know and train to recognize that the cues will push to towards a skidding turn that is too slow you have a better chance of checking yourself before you do something based on instincts honed by flying at altitude that down low can kill you.
> >
> > I do not know how strong these effects are but a ride with a competent check pilot/instructor might be able to inform how strong the tendency is.
> >
> > That's my theory anyway.
> >
> > 9B
>
> BTW, that's one reason why I tend to carry a bit more airspeed until I'm on final (like Kirk). I know that if I get a surprise or distraction on the turn to final with a bigger speed margin I will have more time to sort the distraction before airspeed bleeds off. That works in my -27. I don't do it in a Duo.
>
> 9B

John Carlyle

March 5th 14, 10:10 PM

Yes, indeed! That was just one of several "interesting" experiences I had a that contest...

-John, Q3

On Wednesday, March 5, 2014 3:37:08 PM UTC-5, firsys wrote:
> Always check for that low airplane dragging it in on a long final.
>
> JMF
>
> At 18:08 05 March 2014, John Carlyle wrote:
> >I tend to keep high until on final, just to keep my options
> open,
> >but my speed stays pretty much constant. Being high has helped me on
> >severa=
> >l occasions to delay a bit (once a person behind me with no radio landed
> >un=
> >der me, another time someone drove onto the field).
>
> >-John, Q3

Martin Gregorie[_5_]

March 5th 14, 11:38 PM

On Tue, 04 Mar 2014 17:45:10 -0700, Dan Marotta wrote:

> It's not just the view, though with experience you get to recognize
> rates of change, there's also sound and control feel. But I think
> everyone (including myself) steals the occasional peek at the airspeed
> indicator as well.
>
Yes, and I like to have the ASI top and centre in the panel because this
way the airfield remains in my peripheral vision when I glance at it.

--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

Dan Marotta

March 6th 14, 12:18 AM

<snort, chuckle>...

"John Carlyle" > wrote in message
...
> Thanks, Dan. I suspected you'd keep on with what was familiar to you.
>
> -John, Q3
>
> PS - My Navy buddies tell me they do circling approaches because the
> airstrip is moving. Air Force pilots copy Navy pilots because the field
> knows an Air Force pilot is coming and it will run away... <grin>
>
> On Wednesday, March 5, 2014 11:10:00 AM UTC-5, Dan Marotta wrote:
>> John,
>>
>> Yes, I would. It's the pattern I've flown for 40+ years and it's always
>> worked well for me. I would not consider changing to a square base with
>> a
>> 90 degree turn to final during a critical outlanding at a fenced field.
>> Likewise, I wouldn't advise anyone to switch to a circling landing under
>> the
>> same circumstances.
>>
>> I plan my patterns to roll to a stop at the same location every time
>> using
>> minimal wheel brake. I do this with calm winds and 30+ kt winds. I find
>> it
>> easier to plan and execute simply by changing the point where I begin my
>> final turn.
>>
>> PS - Navy pilots can't land, then only crash and hope the wire stops them
>> before they go over the side. ;-)
>>
>> "John Carlyle" > wrote in message
>> ...
>> > Dan,
>> >
>> > Would you do a circling approach if you were going into a difficult
>> > strip,
>> > too? Say, a narrow cornfield surrounded by trees. I ask because the
>> > Navy
>> > pilots I know who fly gliders have reverted to the non-circling
>> > approach.
>> >
>> > -John, Q3
>> >
>>
>> > On Tuesday, March 4, 2014 12:59:10 PM UTC-5, Dan Marotta wrote:
>>
>> >> I fly my pattern just like Kirk, though a little higher and faster at
>> >> the
>>
>> >> start. I begin my descending final turn when abeam the touchdown
>> >> point
>>
>> >> and
>>
>> >> roll out on final at about 200 ft and over the numbers. I do this
>> >> both
>>
>> >> in
>>
>> >> my LAK and in the tow planes.
>>
>> >>
>>
>> >> I did it this way in the Air Force and when I flew a King Air for
>>
>> >> FlightSafety. The only exception was in the B-727. Gotta be gentle
>> >> for
>>
>> >> the
>>
>> >> pax.
>

BobW

March 6th 14, 03:01 AM

On 3/5/2014 2:53 PM, John Carlyle wrote:
> Agree with your three points of how pilots get into trouble. I also agree
> that training is important, and that it's never a bad idea to take a ride
> with an instructor.
>
> I'm not sure I buy your theory of an optical illusion in your peripheral
> vision causing your central vision and inner ear to start giving you bad
> data, though. It takes time (probably a minute) without good visual cues
> for your inner ear to start disconnecting from reality.

Apologies for the thread drift, but my experience strongly suggests the
"probably a minute" for inner ear to disconnect from reality is "probably
(way?) too long."

I once inadvertently entered an utterly benign (no overdevelopment anywhere
that day) thermal cloud by horribly misjudging the base in conjunction with a
honking climb rate. In the dry intermountain west, racing another guy half a
mile away over the plains of eastern Colorado, it went from CAVU VFR to
solidly-opaque IFR more or less instantly. Flying in a
large-deflection-landing-flap-equipped sailplane (no spoilers) thousands of
feet agl in the middle of nowhere, I wasn't worried about pulling my wings
off, but I *was* distinctly irked at my poor judgment, mostly because if I
didn't fly out the side of the cloud quickly, my buddy would gain considerably
on me. (Standard glider pilot priorities!)

I'd at least had the sense to establish my climb near the far edge of the
miles-long cloud, had a long-established bank angle/turn-rate, and figured I'd
a good chance of rolling out on a heading to have me clear of the cloud within
no more than 5-10 seconds at the most. Without moving my head, once inside the
solidly opaque cloud, and not touching the controls until estimating it was
time to roll out, I did so, timing/estimating wings level, and waited. The
only thing that happened "instantly" was violent vertigo, and within 15
seconds several things were clear: 1) I wasn't going to exit the side of the
cloud; 2) I'd stalled at least once (at which point I pulled on full flaps);
and 3) it was anyone's guess how long I'd be in the cloud and what my flight
path might be while there. Ultimately, I lost 700 feet from my max altitude
before exiting the thing, out the bottom, steeply banked the opposite
direction from that entered, and never knowingly having commanded bank after
the attempt to unbank to level. My buddy was nowhere in sight, of course.

Point being, don't bet your life on having much time IFR before losing
complete control of your glider. Secondary point being (of course!) don't go
IFR at all, but if you DO go IFR be prepared to lose your wings and maybe your
life unless your glider has gobs of disposable drag...as has had every
landing-flap-equipped sailplane I've flown. Wonderful things, large deflection
flaps!

Bob - occasionally bozo - W.

kirk.stant

March 6th 14, 04:03 AM

On Wednesday, March 5, 2014 12:08:55 PM UTC-6, John Carlyle wrote:

> Thank for writing that - very interesting that you mix approach types.

My experience is that you can never be sure that you will be able to fly a "textbook" pattern, so better to be comfortable in a variety of situations. It's a matter of getting your glider from where it is to short final to your desired landing area, at a safe speed and altitude for the existing conditions. Patterns are guides - but one can land safely from all sorts of patterns; one can also (as we are proving) crash from "textbook" patterns.

> I'm not too clear about your comment "always flying the same pattern into the same airfield pretty much guarantees that your first landout will be exciting". I always use a downwind-base-final pattern, I've logged 10 landouts in farmers fields, and except for having to dodge an electric wire fence once they were low or no drama events (although some of the retrieves were interesting).

If you have the luxury of large fields and plenty of time, then setting up a "standard" pattern is always a good option - but what if you don't have those options? You may find on base that the field you picked is not landable, or the wind changes 180 degrees due to a gust front; you may be following a valley and have to suddenly land in that field on your left; or you may get back to your own field and be in a gaggle of gliders all vying for the same runway at the same time. Most of my landouts have been benign also - but I've also done a couple of final glides into fields that I couldn't see and the pattern consisted of one turn, gear & flaps down, and land. I think you have to be prepared for these kinds of eventualities, and be able to fly your glider safely when low and stressed. That takes planning and practice.

> Your "de-stabilized" (non-constant airspeed) approach comment was also interesting. I tend to keep high until on final, just to keep my options open, but my speed stays pretty much constant. Being high has helped me on several occasions to delay a bit (once a person behind me with no radio landed under me, another time someone drove onto the field). Do I understand correctly that you tend to keep your energy in speed rather than altitude?

Energy is the key, high and fast is nice, lower and fast is OK, but slow and low is never good until over the threshold! I see my "hot" pattern speed as a minimum and if it gets a bit high I don't worry about it - final is a fine time to decelerate and get ready to land. Again, it depends on the situation - if there are lots of gliders around trying to land, then playing off altitude and speed is a useful tool to use to get sequenced into the flow - and extra speed on final is good unless you KNOW you have to land short! If there is nothing going on and it's the last landing of the day, then a perfect, constant speed pattern is a fun challenge; but if it's a hectic arrival, I may have to maneuver aggressively to get down; then speed control is more of the "stay fast, stay fast, stay fast..." variety until the immediate problem of where to go is solved. Stall/spins make lousy pattern entries!

Cheers,

Kirk
66

Bill D

March 6th 14, 04:15 AM

On Wednesday, March 5, 2014 8:01:30 PM UTC-7, BobW wrote:
> On 3/5/2014 2:53 PM, John Carlyle wrote:
>
> > Agree with your three points of how pilots get into trouble. I also agree
>
> > that training is important, and that it's never a bad idea to take a ride
>
> > with an instructor.
>
> >
>
> > I'm not sure I buy your theory of an optical illusion in your peripheral
>
> > vision causing your central vision and inner ear to start giving you bad
>
> > data, though. It takes time (probably a minute) without good visual cues
>
> > for your inner ear to start disconnecting from reality.
>
>
>
> Apologies for the thread drift, but my experience strongly suggests the
>
> "probably a minute" for inner ear to disconnect from reality is "probably
>
> (way?) too long."
>
>
>
> I once inadvertently entered an utterly benign (no overdevelopment anywhere
>
> that day) thermal cloud by horribly misjudging the base in conjunction with a
>
> honking climb rate. In the dry intermountain west, racing another guy half a
>
> mile away over the plains of eastern Colorado, it went from CAVU VFR to
>
> solidly-opaque IFR more or less instantly. Flying in a
>
> large-deflection-landing-flap-equipped sailplane (no spoilers) thousands of
>
> feet agl in the middle of nowhere, I wasn't worried about pulling my wings
>
> off, but I *was* distinctly irked at my poor judgment, mostly because if I
>
> didn't fly out the side of the cloud quickly, my buddy would gain considerably
>
> on me. (Standard glider pilot priorities!)
>
>
>
> I'd at least had the sense to establish my climb near the far edge of the
>
> miles-long cloud, had a long-established bank angle/turn-rate, and figured I'd
>
> a good chance of rolling out on a heading to have me clear of the cloud within
>
> no more than 5-10 seconds at the most. Without moving my head, once inside the
>
> solidly opaque cloud, and not touching the controls until estimating it was
>
> time to roll out, I did so, timing/estimating wings level, and waited. The
>
> only thing that happened "instantly" was violent vertigo, and within 15
>
> seconds several things were clear: 1) I wasn't going to exit the side of the
>
> cloud; 2) I'd stalled at least once (at which point I pulled on full flaps);
>
> and 3) it was anyone's guess how long I'd be in the cloud and what my flight
>
> path might be while there. Ultimately, I lost 700 feet from my max altitude
>
> before exiting the thing, out the bottom, steeply banked the opposite
>
> direction from that entered, and never knowingly having commanded bank after
>
> the attempt to unbank to level. My buddy was nowhere in sight, of course.
>
>
>
> Point being, don't bet your life on having much time IFR before losing
>
> complete control of your glider. Secondary point being (of course!) don't go
>
> IFR at all, but if you DO go IFR be prepared to lose your wings and maybe your
>
> life unless your glider has gobs of disposable drag...as has had every
>
> landing-flap-equipped sailplane I've flown. Wonderful things, large deflection
>
> flaps!
>
>
>
> Bob - occasionally bozo - W.

The best data says a pilot will lose control of the aircraft in mere seconds in a cloud if not trained and equipped for instrument flight.

The inner ear serves no useful purpose in aviators. It only serves to induce one of the many aviation specific illusions and/or vertigo. We didn't evolve to fly so we must learn to deal with our limitations. The best pilots learn to ignore vestibular sensations and rely on sight - viewing instruments or outside cues. This lesson is best learned under a hood with a CFII in the right seat.

Eric Greenwell[_4_]

March 6th 14, 06:25 AM

Bill D wrote, On 3/3/2014 7:54 PM:
> The argument which says one should avoid low turns ignores the fact
> that every glider flight ends with at least one turn at or below 300'
> AGL.

I'm on short final at 300' AGL, because I usually enter the pattern at
about 1000' AGL. My turns to base are typically 600-700' AGL. I don't
use spoilers until I'm on final, because using spoiler earlier means my
downwind/base and base/final turns will be lower than they would be
otherwise.

Am I that unusual? Why would you want to be as low 300' on your turn to
final?

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)

Chris Rollings[_2_]

March 6th 14, 11:08 AM

At 04:15 06 March 2014, Bill D wrote:
>On Wednesday, March 5, 2014 8:01:30 PM UTC-7, BobW wrote:
>> On 3/5/2014 2:53 PM, John Carlyle wrote:
>>=20
>> > Agree with your three points of how pilots get into trouble. I also
>agr=
>ee
>>=20
>> > that training is important, and that it's never a bad idea to take a
>ri=
>de
>>=20
>> > with an instructor.
>>=20
>> >
>>=20
>> > I'm not sure I buy your theory of an optical illusion in your
>periphera=
>l
>>=20
>> > vision causing your central vision and inner ear to start giving you
>ba=
>d
>>=20
>> > data, though. It takes time (probably a minute) without good visual
>cue=
>s
>>=20
>> > for your inner ear to start disconnecting from reality.
>>=20
>>=20
>>=20
>> Apologies for the thread drift, but my experience strongly suggests
the=
>=20
>>=20
>> "probably a minute" for inner ear to disconnect from reality is
>"probably=
>=20
>>=20
>> (way?) too long."
>>=20
>>=20
>>=20
>> I once inadvertently entered an utterly benign (no overdevelopment
>anywhe=
>re=20
>>=20
>> that day) thermal cloud by horribly misjudging the base in conjunction
>wi=
>th a=20
>>=20
>> honking climb rate. In the dry intermountain west, racing another guy
>hal=
>f a=20
>>=20
>> mile away over the plains of eastern Colorado, it went from CAVU VFR
to=
>=20
>>=20
>> solidly-opaque IFR more or less instantly. Flying in a=20
>>=20
>> large-deflection-landing-flap-equipped sailplane (no spoilers)
thousands
>=
>of=20
>>=20
>> feet agl in the middle of nowhere, I wasn't worried about pulling my
>wing=
>s=20
>>=20
>> off, but I *was* distinctly irked at my poor judgment, mostly because
if
>=
>I=20
>>=20
>> didn't fly out the side of the cloud quickly, my buddy would gain
>conside=
>rably=20
>>=20
>> on me. (Standard glider pilot priorities!)
>>=20
>>=20
>>=20
>> I'd at least had the sense to establish my climb near the far edge of
>the=
>=20
>>=20
>> miles-long cloud, had a long-established bank angle/turn-rate, and
>figure=
>d I'd=20
>>=20
>> a good chance of rolling out on a heading to have me clear of the cloud
>w=
>ithin=20
>>=20
>> no more than 5-10 seconds at the most. Without moving my head, once
>insid=
>e the=20
>>=20
>> solidly opaque cloud, and not touching the controls until estimating it
>w=
>as=20
>>=20
>> time to roll out, I did so, timing/estimating wings level, and waited.
>Th=
>e=20
>>=20
>> only thing that happened "instantly" was violent vertigo, and within
15=
>=20
>>=20
>> seconds several things were clear: 1) I wasn't going to exit the side
of
>=
>the=20
>>=20
>> cloud; 2) I'd stalled at least once (at which point I pulled on full
>flap=
>s);=20
>>=20
>> and 3) it was anyone's guess how long I'd be in the cloud and what my
>fli=
>ght=20
>>=20
>> path might be while there. Ultimately, I lost 700 feet from my max
>altitu=
>de=20
>>=20
>> before exiting the thing, out the bottom, steeply banked the
opposite=20
>>=20
>> direction from that entered, and never knowingly having commanded bank
>af=
>ter=20
>>=20
>> the attempt to unbank to level. My buddy was nowhere in sight, of
course.
>>=20
>>=20
>>=20
>> Point being, don't bet your life on having much time IFR before
losing=20
>>=20
>> complete control of your glider. Secondary point being (of course!)
>don't=
> go=20
>>=20
>> IFR at all, but if you DO go IFR be prepared to lose your wings and
>maybe=
> your=20
>>=20
>> life unless your glider has gobs of disposable drag...as has had
every=20
>>=20
>> landing-flap-equipped sailplane I've flown. Wonderful things, large
>defle=
>ction=20
>>=20
>> flaps!
>>=20
>>=20
>>=20
>> Bob - occasionally bozo - W.
>
>The best data says a pilot will lose control of the aircraft in mere
>second=
>s in a cloud if not trained and equipped for instrument flight.
>
>The inner ear serves no useful purpose in aviators. It only serves to
>indu=
>ce one of the many aviation specific illusions and/or vertigo. We didn't
>e=
>volve to fly so we must learn to deal with our limitations. The best
>pilot=
>s learn to ignore vestibular sensations and rely on sight - viewing
>instrum=
>ents or outside cues. This lesson is best learned under a hood with a
>CFII=
> in the right seat.
>

One small piece of advice on this, keep your head still, turning it to look
left and right and upwards greatly increases the disorientatation as you
move semi-circular canals in and out of the plane of rotation.

Getting people to do that whilst in cloud has always been part of my cloud
flying training routine, though it normally comes after a few cloud flying
trips to build up experience.

Chris Rollings[_2_]

March 6th 14, 11:10 AM

At 06:25 06 March 2014, Eric Greenwell wrote:
>Bill D wrote, On 3/3/2014 7:54 PM:
>> The argument which says one should avoid low turns ignores the fact
>> that every glider flight ends with at least one turn at or below 300'
>> AGL.
>
>I'm on short final at 300' AGL, because I usually enter the pattern at
>about 1000' AGL. My turns to base are typically 600-700' AGL. I don't
>use spoilers until I'm on final, because using spoiler earlier means my
>downwind/base and base/final turns will be lower than they would be
>otherwise.
>
>Am I that unusual? Why would you want to be as low 300' on your turn to
>final?
>
>--
>Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
>email me)
>
Perhaps because you only got 1100 feet off your winch launch and you used
400 feet of that failing to find a thermal.

Eric Greenwell[_4_]

March 7th 14, 04:38 AM

Chris Rollings wrote, On 3/6/2014 3:10 AM:
> At 06:25 06 March 2014, Eric Greenwell wrote:
>> Bill D wrote, On 3/3/2014 7:54 PM:
>>> The argument which says one should avoid low turns ignores the fact
>>> that every glider flight ends with at least one turn at or below 300'
>>> AGL.
>>
>> I'm on short final at 300' AGL, because I usually enter the pattern at
>> about 1000' AGL. My turns to base are typically 600-700' AGL. I don't
>> use spoilers until I'm on final, because using spoiler earlier means my
>> downwind/base and base/final turns will be lower than they would be
>> otherwise.
>>
>> Am I that unusual? Why would you want to be as low 300' on your turn to
>> final?
>>
>> --
>> Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
>> email me)
>>
> Perhaps because you only got 1100 feet off your winch launch and you used
> 400 feet of that failing to find a thermal.

So, not exactly a "want", but an acceptable compromise between safety
and soaring? If you could routinely launch to 2000', would you be much
less inclined to enter the pattern so low that the turn to final would
be 300'?

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)

[email protected]

March 7th 14, 05:02 AM

On Thursday, March 6, 2014 8:38:59 PM UTC-8, Eric Greenwell wrote:

> So, not exactly a "want", but an acceptable compromise between safety
> and soaring? If you could routinely launch to 2000', would you be much
> less inclined to enter the pattern so low that the turn to final would
> be 300'?
>

I thought turning final at 300-350' was pretty common. But I come from a Navy/Marine Corps family that keeps the pattern pretty tight.

;-)

9B

John Carlyle

March 7th 14, 03:24 PM

Bob,

I've never experienced vertigo during flight (only on the ground from illness or alcohol issues), so I'm happy to admit I was wrong by a factor of 10 in estimating its onset. Can we settle on a vertigo onset of 5-10 seconds for sake of argument?

Getting back to the original topic, there we are, in our base to final turn with our ASI reading yellow diamond value plus half the wind speed. Suppose we shift our gaze from over the nose (where we were looking at pitch, yaw string and bank angle) towards the inside wing (to check that the airport hasn't run away). In our peripheral vision we see some unusual motion of the wing. We can either ignore it and keep on flying the plane, or we can focus on it. If we ignore it, no problem, but if we focus on it there are four possibilities as to what can happen next.

First case, we tell ourselves "that's interesting, but I've got a plane to fly", we shift our gaze back to the nose, keep the turn coordinated and successfully land. Second case, we tell ourselves "that's interesting, I've never seen anything like that, I wonder why that's happening, doesn't matter now, I've got a plane to fly", we shift our gaze back to the nose, keep the turn coordinated and successfully land. Third case, we tell ourselves "that's interesting, I've never seen anything like that, I wonder why that's happening, hmmm, maybe I should put in some more rudder", and we don't land successfully. Fourth case, we tell ourselves "that's interesting, I've never seen anything like that, I wonder why that's happening, hmmm, wow those trees are close and they're really moving funny, I'm going to have to remember this to tell the guys all about it, I wonder if I bleed off too much altitude, hey there's a good looking lady down there, wonder if she sees me up here, whoops, I'm dizzy and don't feel too good, gee those trees are really close and now they're spinning around and around, oh I'm sick" and we don't land successfully.

In the first two cases, there's no problem. I think we can agree case four is very, very unlikely, as no one is likely to fixate on something unusual for so long (5-10 seconds) when they're low that they'll succumb to vertigo and crash. It's drummed into us as students that above all else, we need to fly the plane, no matter what.

But what about case three? Some in this thread have said it's possible, and that one needs ground reference training to become familiar with the reverse wing tip movement sensation so you don't try to "correct it". Maybe, but I'd argue no. First, you're going to have to quit doing something very important (maintaining a coordinated turn while low) to focus on something secondary in order to realize what's happening. Next you're going to have to "do something" impulsively without cross-checking with a quick gaze at your yaw string that something really needs to be done to maintain your coordinated turn. If you're the sort that would be susceptible to these actions, I'd suggest there's training in other areas that needs to be accomplished first before you consider ground reference training.

Now, let me follow your topic drift. Suppose it takes 5-10 seconds without outside orientation references for vertigo to set in. Why wouldn't all the passengers in the center section of a widebody at night get nauseous? If your answer is "they use the cabin as an orientation reference for their inner ear", then why can't the pilot use his cockpit features for the same purpose? He'll probably still lose control of the aircraft, but he shouldn't become nauseous.

-John, Q3

On Wednesday, March 5, 2014 10:01:30 PM UTC-5, BobW wrote:
> Apologies for the thread drift, but my experience strongly suggests the
> "probably a minute" for inner ear to disconnect from reality is "probably
> (way?) too long."
>
> I once inadvertently entered an utterly benign (no overdevelopment anywhere
> that day) thermal cloud by horribly misjudging the base in conjunction with a
> honking climb rate. In the dry intermountain west, racing another guy half a
> mile away over the plains of eastern Colorado, it went from CAVU VFR to
> solidly-opaque IFR more or less instantly. Flying in a
> large-deflection-landing-flap-equipped sailplane (no spoilers) thousands of
> feet agl in the middle of nowhere, I wasn't worried about pulling my wings
> off, but I *was* distinctly irked at my poor judgment, mostly because if I
> didn't fly out the side of the cloud quickly, my buddy would gain considerably
> on me. (Standard glider pilot priorities!)
>
> I'd at least had the sense to establish my climb near the far edge of the
> miles-long cloud, had a long-established bank angle/turn-rate, and figured I'd
> a good chance of rolling out on a heading to have me clear of the cloud within
> no more than 5-10 seconds at the most. Without moving my head, once inside the
> solidly opaque cloud, and not touching the controls until estimating it was
> time to roll out, I did so, timing/estimating wings level, and waited. The
> only thing that happened "instantly" was violent vertigo, and within 15
> seconds several things were clear: 1) I wasn't going to exit the side of the
> cloud; 2) I'd stalled at least once (at which point I pulled on full flaps);
> and 3) it was anyone's guess how long I'd be in the cloud and what my flight
> path might be while there. Ultimately, I lost 700 feet from my max altitude
> before exiting the thing, out the bottom, steeply banked the opposite
> direction from that entered, and never knowingly having commanded bank after
> the attempt to unbank to level. My buddy was nowhere in sight, of course.
>
> Point being, don't bet your life on having much time IFR before losing
> complete control of your glider. Secondary point being (of course!) don't go
> IFR at all, but if you DO go IFR be prepared to lose your wings and maybe your
> life unless your glider has gobs of disposable drag...as has had every
> landing-flap-equipped sailplane I've flown. Wonderful things, large deflection
> flaps!
>
> Bob - occasionally bozo - W.

John Carlyle

March 7th 14, 03:47 PM

Kirk,

Thanks for your detailed answer. I understand what you're saying - be flexible and be prepared to do what you gotta do when you gotta do it.

I tend to make mistakes when I rush, so I try to keep ahead of the situation. During landings I do this by using the typical downwind-base-final pattern. It doesn't always work out, of course, during BFRs it's common for me to get a release on tow and hear the instructor say "where you going to land now"? That practice has helped immensely with the problems you mentioned of being in a gaggle of gliders all trying to land now, or needing to make a quick change of farmers field when the first choice had to be ruled out.

-John, Q3

On Wednesday, March 5, 2014 11:03:59 PM UTC-5, kirk.stant wrote:
> On Wednesday, March 5, 2014 12:08:55 PM UTC-6, John Carlyle wrote:
> > Thank for writing that - very interesting that you mix approach types.
>
> My experience is that you can never be sure that you will be able to fly a "textbook" pattern, so better to be comfortable in a variety of situations. It's a matter of getting your glider from where it is to short final to your desired landing area, at a safe speed and altitude for the existing conditions. Patterns are guides - but one can land safely from all sorts of patterns; one can also (as we are proving) crash from "textbook" patterns.
>
> > I'm not too clear about your comment "always flying the same pattern into the same airfield pretty much guarantees that your first landout will be exciting". I always use a downwind-base-final pattern, I've logged 10 landouts in farmers fields, and except for having to dodge an electric wire fence once they were low or no drama events (although some of the retrieves were interesting).
>
> If you have the luxury of large fields and plenty of time, then setting up a "standard" pattern is always a good option - but what if you don't have those options? You may find on base that the field you picked is not landable, or the wind changes 180 degrees due to a gust front; you may be following a valley and have to suddenly land in that field on your left; or you may get back to your own field and be in a gaggle of gliders all vying for the same runway at the same time. Most of my landouts have been benign also - but I've also done a couple of final glides into fields that I couldn't see and the pattern consisted of one turn, gear & flaps down, and land. I think you have to be prepared for these kinds of eventualities, and be able to fly your glider safely when low and stressed. That takes planning and practice.
>
> > Your "de-stabilized" (non-constant airspeed) approach comment was also interesting. I tend to keep high until on final, just to keep my options open, but my speed stays pretty much constant. Being high has helped me on several occasions to delay a bit (once a person behind me with no radio landed under me, another time someone drove onto the field). Do I understand correctly that you tend to keep your energy in speed rather than altitude?
>
> Energy is the key, high and fast is nice, lower and fast is OK, but slow and low is never good until over the threshold! I see my "hot" pattern speed as a minimum and if it gets a bit high I don't worry about it - final is a fine time to decelerate and get ready to land. Again, it depends on the situation - if there are lots of gliders around trying to land, then playing off altitude and speed is a useful tool to use to get sequenced into the flow - and extra speed on final is good unless you KNOW you have to land short! If there is nothing going on and it's the last landing of the day, then a perfect, constant speed pattern is a fun challenge; but if it's a hectic arrival, I may have to maneuver aggressively to get down; then speed control is more of the "stay fast, stay fast, stay fast..." variety until the immediate problem of where to go is solved. Stall/spins make lousy pattern entries!
>
> Cheers,
> Kirk
> 66

Bob Whelan[_3_]

March 7th 14, 04:43 PM

On 3/7/2014 8:24 AM, John Carlyle wrote:
> Bob,
>
> I've never experienced vertigo during flight (only on the ground from
> illness or alcohol issues), so I'm happy to admit I was wrong by a factor
> of 10 in estimating its onset. Can we settle on a vertigo onset of 5-10
> seconds for sake of argument?

John - I'm 'happy to settle on any time-interval anyone would like' for
vertigo onset, because - as I've no doubt you well realize - what really
matters is that it WILL happen, and if Joe Pilot doesn't already have a
well-rehearsed Plan B ready for PDQ implementation, he's just transitioned
from a "Crud!" or "Oh s**t!" situation to a deadly one.
>
> Getting back to the original topic, there we are, in our base to final turn
> with our ASI reading yellow diamond value plus half the wind speed. Suppose
> we shift our gaze from over the nose (where we were looking at pitch, yaw
> string and bank angle) towards the inside wing (to check that the airport
> hasn't run away). In our peripheral vision we see some unusual motion of
> the wing. We can either ignore it and keep on flying the plane, or we can
> focus on it. If we ignore it, no problem, but if we focus on it there are
> four possibilities as to what can happen next.
>
> First case, we tell ourselves "that's interesting, but I've got a plane to
> fly", we shift our gaze back to the nose, keep the turn coordinated and
> successfully land. Second case, we tell ourselves "that's interesting, I've
> never seen anything like that, I wonder why that's happening, doesn't
> matter now, I've got a plane to fly", we shift our gaze back to the nose,
> keep the turn coordinated and successfully land. Third case, we tell
> ourselves "that's interesting, I've never seen anything like that, I wonder
> why that's happening, hmmm, maybe I should put in some more rudder", and we
> don't land successfully. Fourth case, we tell ourselves "that's
> interesting, I've never seen anything like that, I wonder why that's
> happening, hmmm, wow those trees are close and they're really moving funny,
> I'm going to have to remember this to tell the guys all about it, I wonder
> if I bleed off too much altitude, hey there's a good looking lady down
> there, wonder if she sees me up here, whoops, I'm dizzy and don't feel too
> good, gee those trees are really close and now they're spinning around and
> around, oh I'm sick" and we don't land successfully.
>
> In the first two cases, there's no problem. I think we can agree case four
> is very, very unlikely, as no one is likely to fixate on something unusual
> for so long (5-10 seconds) when they're low that they'll succumb to vertigo
> and crash. It's drummed into us as students that above all else, we need to
> fly the plane, no matter what.
>
> But what about case three? Some in this thread have said it's possible, and
> that one needs ground reference training to become familiar with the
> reverse wing tip movement sensation so you don't try to "correct it".
> Maybe, but I'd argue no. First, you're going to have to quit doing
> something very important (maintaining a coordinated turn while low) to
> focus on something secondary in order to realize what's happening. Next
> you're going to have to "do something" impulsively without cross-checking
> with a quick gaze at your yaw string that something really needs to be done
> to maintain your coordinated turn. If you're the sort that would be
> susceptible to these actions, I'd suggest there's training in other areas
> that needs to be accomplished first before you consider ground reference
> training.

I don't fundamentally disagree with your assessments one bit. The trick for an
instructor (or Joe Pilot, for that matter, if J.P. is vaguely insightful) is
to decide if Joe Pilot is in fact susceptible to life-threatening
distractions. I pretty quickly in my 'pilot career' concluded I was not (or
for darned sure intended to make certain I didn't fall prey to that stupid
trap), and my motivation was the dead pilots whom I suspected WERE for some
reason or other. In either case, additional training on SOMEthing related to
'how to properly fly a (definitionally non-standard) pattern' seems in order. :-)

>
> Now, let me follow your topic drift. Suppose it takes 5-10 seconds without
> outside orientation references for vertigo to set in. Why wouldn't all the
> passengers in the center section of a widebody at night get nauseous? If
> your answer is "they use the cabin as an orientation reference for their
> inner ear", then why can't the pilot use his cockpit features for the same
> purpose? He'll probably still lose control of the aircraft, but he
> shouldn't become nauseous.

Indeed...

For the record, I've not yet experienced nausea with my vertigo incidents
(in-glider, on-ground, in FAA 'IFR chair', etc.). In any event, small comfort
hitting the ground comfortably and out of control as opposed to queasily and
out of control, eh? ;-)

Bob W.

kirk.stant

March 7th 14, 04:56 PM

On Friday, March 7, 2014 9:24:21 AM UTC-6, John Carlyle wrote:
> But what about case three? Some in this thread have said it's possible, and that one needs ground reference training to become familiar with the reverse wing tip movement sensation so you don't try to "correct it". Maybe, but I'd argue no. First, you're going to have to quit doing something very important (maintaining a coordinated turn while low) to focus on something secondary in order to realize what's happening. Next you're going to have to "do something" impulsively without cross-checking with a quick gaze at your yaw string that something really needs to be done to maintain your coordinated turn. If you're the sort that would be susceptible to these actions, I'd suggest there's training in other areas that needs to be accomplished first before you consider ground reference training.

I don't understand why the motion of the wingtip over the ground is such a big deal? Who looks (focuses) at their wingtip in flight? I'm looking way beyond it at some other object - who cares what my wingtip is doing? In a steady turn, once established, it would take a lot of rudder to significantly move the nose and create dangerous yaw - who boots the rudder while in a steady turn? I think there is something more basic going on here - poor/lazy airmanship! Get out and fly more; practice stalls/departures/spiral dive recoveries, be aggressive in your pattern - fly down to the flare (fast, steep, in control), instead of being scared to get close to the ground, etc....

> Now, let me follow your topic drift. Suppose it takes 5-10 seconds without outside orientation references for vertigo to set in. Why wouldn't all the passengers in the center section of a widebody at night get nauseous? If your answer is "they use the cabin as an orientation reference for their inner ear", then why can't the pilot use his cockpit features for the same purpose? He'll probably still lose control of the aircraft, but he shouldn't become nauseous.

Because the airliner is always in coordinated flight and the turn/roll rates as very slow. Trust me, every passenger in an airliner doing turns in clouds or at night has vertigo, but since they are unaware of it, unless they are looking out the window when they pop out of a cloud in a turn they will not become aware of it or get nausious. Next time you fly commercial, focus your gaze forward down the cabin during the takeoff acceleration, and you will sense the plane pitching up significantly BEFORE rotation (acceleration effect on inner ear - vertigo), then look out the window and note how fast your equilibrium reestablishes. This really was fun in something like a C-130 or C-141 with no windows and good acceleration, it felt like you pitched up 10 degrees immediately!

Kirk
66

Eric Bick (1DB)

March 10th 14, 05:37 PM

On Friday, March 7, 2014 7:47:33 AM UTC-8, John Carlyle wrote:
> Kirk,
>
>
>
> Thanks for your detailed answer. I understand what you're saying - be flexible and be prepared to do what you gotta do when you gotta do it.
>
>
>
> I tend to make mistakes when I rush, so I try to keep ahead of the situation. During landings I do this by using the typical downwind-base-final pattern. It doesn't always work out, of course, during BFRs it's common for me to get a release on tow and hear the instructor say "where you going to land now"? That practice has helped immensely with the problems you mentioned of being in a gaggle of gliders all trying to land now, or needing to make a quick change of farmers field when the first choice had to be ruled out.
>
>
>
> -John, Q3
>
>
>
> On Wednesday, March 5, 2014 11:03:59 PM UTC-5, kirk.stant wrote:
>
> > On Wednesday, March 5, 2014 12:08:55 PM UTC-6, John Carlyle wrote:
>
> > > Thank for writing that - very interesting that you mix approach types..
>
> >
>
> > My experience is that you can never be sure that you will be able to fly a "textbook" pattern, so better to be comfortable in a variety of situations. It's a matter of getting your glider from where it is to short final to your desired landing area, at a safe speed and altitude for the existing conditions. Patterns are guides - but one can land safely from all sorts of patterns; one can also (as we are proving) crash from "textbook" patterns..
>
> >
>
> > > I'm not too clear about your comment "always flying the same pattern into the same airfield pretty much guarantees that your first landout will be exciting". I always use a downwind-base-final pattern, I've logged 10 landouts in farmers fields, and except for having to dodge an electric wire fence once they were low or no drama events (although some of the retrieves were interesting).
>
> >
>
> > If you have the luxury of large fields and plenty of time, then setting up a "standard" pattern is always a good option - but what if you don't have those options? You may find on base that the field you picked is not landable, or the wind changes 180 degrees due to a gust front; you may be following a valley and have to suddenly land in that field on your left; or you may get back to your own field and be in a gaggle of gliders all vying for the same runway at the same time. Most of my landouts have been benign also - but I've also done a couple of final glides into fields that I couldn't see and the pattern consisted of one turn, gear & flaps down, and land. I think you have to be prepared for these kinds of eventualities, and be able to fly your glider safely when low and stressed. That takes planning and practice.
>
> >
>
> > > Your "de-stabilized" (non-constant airspeed) approach comment was also interesting. I tend to keep high until on final, just to keep my options open, but my speed stays pretty much constant. Being high has helped me on several occasions to delay a bit (once a person behind me with no radio landed under me, another time someone drove onto the field). Do I understand correctly that you tend to keep your energy in speed rather than altitude?
>
> >
>
> > Energy is the key, high and fast is nice, lower and fast is OK, but slow and low is never good until over the threshold! I see my "hot" pattern speed as a minimum and if it gets a bit high I don't worry about it - final is a fine time to decelerate and get ready to land. Again, it depends on the situation - if there are lots of gliders around trying to land, then playing off altitude and speed is a useful tool to use to get sequenced into the flow - and extra speed on final is good unless you KNOW you have to land short! If there is nothing going on and it's the last landing of the day, then a perfect, constant speed pattern is a fun challenge; but if it's a hectic arrival, I may have to maneuver aggressively to get down; then speed control is more of the "stay fast, stay fast, stay fast..." variety until the immediate problem of where to go is solved. Stall/spins make lousy pattern entries!
>
> >
>
> > Cheers,
>
> > Kirk
>
> > 66

Last Saturday - on downwind - have called pattern on radio - getting ready to turn base (squared off pattern), when I notice tow plane has maybe decided I was just kidding about landing, and touches down on runway - bless his heart - or maybe didn't hear my radio calls. Start turn to base, watching yaw string and speed and runway and tow. I know the ground is still there, but I have to know how cluttered or clear it is. I'm on TLAR so altimeter doesn't really matter at this point. Just know I can still land long or short, but have to decide pretty quickly which, unless tow clears runway. There are three gliders staged on left third of runway (we have a wide dirt runway), and tow is taxiing toward them on right side of runway, so runway is now blocked and my original aim point is meaningless - would hit tow, and if I try to miss tow by going left, I'll hit the staged gliders. If I go right of tow, I'm into the desert and a severely damaged glider. As I turn final, I keep altitude and air speed for either landing short or landing way, way long. Don't like either option, since that's a long push to my trailer, but I gotta fly the glider and be safe - a long push to trailer is better than the other options at this point. Since it's a gusty day, need extra airspeed anyway. Tow is now about even with staged gliders, runway is totally blocked, and I have run out of time. Since it's a gusty day, I don't want to chance getting knocked down (wind shear) trying to land long by flying over everyone, so opt for short and deploy full air brakes and get ready to start a slip since I'm planning on touching down about 400' - 500' shorter than original plan. Still watching airspeed, since I don't want to land short and still end up rolling into the ground gaggle because of too much ground speed. About 1 second later, tow pulls in front of gliders, clearing the right side of the runway, so I go back to original plan. In come the brakes, up comes the nose a bit and I touch down as originally planned. What wingtips? Never saw them. What was I focused on? Just about everything I thought was important, but primarily on landing safely.
Eric Bick