Glider vs. Power Pattern Bank Angle?

In power, they're taught to fly patterns with very little bank angle, whereas
in gliders we're taught to bank at about 45 degrees or so. I well understand
the rationale for banking steeply in gliders, but why are power pilots taught
to do shallow turns?

TIA for the explanation.

Jim Vincent
CFIG
N483SZ
illspam

standard rate turns for most light general aviation is about 15 degrees of
bank... up to 30 degrees is considered the norm for power aircraft..

gliders fly closer in and tighter patterns.. so 45 degrees makes more
since.. can't say I've paid much attention to estimate the bank angle...
granted I fly the tow plane (Pawnee) in the same ground track pattern and
use 45 degrees of bank..

BT

"Jim Vincent" wrote in message
...
In power, they're taught to fly patterns with very little bank angle,
whereas
in gliders we're taught to bank at about 45 degrees or so. I well
understand
the rationale for banking steeply in gliders, but why are power pilots
taught
to do shallow turns?

TIA for the explanation.

Jim Vincent
CFIG
N483SZ
illspam

illspam (Jim Vincent) wrote in message ...
In power, they're taught to fly patterns with very little bank angle, whereas
in gliders we're taught to bank at about 45 degrees or so. I well understand
the rationale for banking steeply in gliders, but why are power pilots taught
to do shallow turns?

The reason is, actually, pretty simple: power planes have god-awfull
visibility; if you bank too steeply you lose visual contact with a key
part of the pattern. This is something to keep in mind while flying in
the vacinity of power planes: if you can't see the cockpit, they can't
see you. In general, the best policy is to assume that they can't see
you and to act accordingly.

Tom Seim
Richland, WA

Tom Seim wrote:
illspam (Jim Vincent) wrote in message ...

In power, they're taught to fly patterns with very little bank angle, whereas
in gliders we're taught to bank at about 45 degrees or so. I well understand
the rationale for banking steeply in gliders, but why are power pilots taught
to do shallow turns?


The reason is, actually, pretty simple: power planes have god-awfull
visibility; if you bank too steeply you lose visual contact with a key
part of the pattern. This is something to keep in mind while flying in
the vacinity of power planes: if you can't see the cockpit, they can't
see you. In general, the best policy is to assume that they can't see
you and to act accordingly.

Tom Seim
Richland, WA
More to the point - most of the time they will not have seen you, even if you
can see the whites of their eyes. Power pilots are not used to looking for
little slivers of white, and don't see what they don't expect. Even if they are
looking for you, which is often not the case.

We have a plague of low time power guys boring inexorably toward their selected
GPS turnpoint. In the far corner of the airfileld, after crossing three active
runways. Many of them are heads down watching the GPS, and don't even see the
winch or gliders. I am convinced some of them never see the airport they are
turning over...

That said I have also had a couple of them see me when I can't find their C172
sized lump. Can be embarassing to realise how easily you can miss something that
big, even when you know it is near, and even the general direction.

The reason is, actually, pretty simple: power planes have god-awfull
visibility; if you bank too steeply you lose visual contact with a key
part of the pattern.

Tom, that makes sense to me for a high wing plane, but not for a low wing
plane. My friend had been taught never to bank too much in the pattern because
of the stall risk, I think. Yet us glider guiders are taught exactly the
opposite. Maybe since we fly the pattern so much closer to stall speed?


Jim Vincent
CFIG
N483SZ
illspam

2 more reasons for the shallow bank turns in power aircraft.

One Valid reason is that many power pilot carry passengers and it is
just more comfortable (less Scary) for the passangers to make
shallower turns.

Second, unfortunatly some of the procedures for making large patterns
with Power have trickled down from the Military and Airlines and have
started to be taught as standard for small single engine aircraft.
While these procedures are appropriate and the safest way to operate
Larger Turbine aircraft it is simply not applicable and can be
dangerous to operate small single engine aircraft this way.

I teach that a 30 degree bank turn should be typical (Vary as
appropriate) for turns in the Pattern for power aircraft This is a
good compromise for comfortable turns and reasonably small pattern
size.

Interestingly Many Pilots (Instructors included) don't seem to realize
that many (not all) aircraft actually are much harder to stall in a
steep turn than a shallow turn. This is because unless the CG is near
or past the aft CG Limit the elevator does not have enough power to
hold the turn and stall the wing. This is somewhat supported by fact
that most stall spin accidents are not initated from a steep turn but
rather from shallow skidded turns. Generally it is actually safer to
use a steeper turn.


Brian
CFIIG/ASEL

illspam (Jim Vincent) wrote in message ...
The reason is, actually, pretty simple: power planes have god-awfull
visibility; if you bank too steeply you lose visual contact with a key
part of the pattern.

Tom, that makes sense to me for a high wing plane, but not for a low wing
plane. My friend had been taught never to bank too much in the pattern because
of the stall risk, I think. Yet us glider guiders are taught exactly the
opposite. Maybe since we fly the pattern so much closer to stall speed?


Jim Vincent
CFIG
N483SZ
illspam

On 11 Jun 2004 05:47:17 -0700, (Brian Case) wrote:

snip

Interestingly Many Pilots (Instructors included) don't seem to realize
that many (not all) aircraft actually are much harder to stall in a
steep turn than a shallow turn. This is because unless the CG is near
or past the aft CG Limit the elevator does not have enough power to
hold the turn and stall the wing. This is somewhat supported by fact
that most stall spin accidents are not initated from a steep turn but
rather from shallow skidded turns. Generally it is actually safer to
use a steeper turn.


snip

I have experienced stall buffet at 60 degrees of bank in a thermal
in a DG-505, and I fly with a forward CG. Granted, stall buffet is
not yet a stall, and the DG's stall characteristics may be pretty
benign, but I no longer trust that a glider will be hard to stall in
steep turns. Because in a turn the inside wing is flying at a higher
AOA than the outside wing, the inside wing will likely stall, and
drop, before the outside wing. I understand that in some gliders
without the newer wing designs this inside wing stall may well be
followed an eye-blink later with an out-the-bottom spin entry.
The "Pooch" may be such a glider.

YMMV of course. I'm just glad to have noticed this.

On 11 Jun 2004 05:26:34 GMT, illspam (Jim Vincent)
wrote:

The reason is, actually, pretty simple: power planes have god-awfull
visibility; if you bank too steeply you lose visual contact with a key
part of the pattern.

Tom, that makes sense to me for a high wing plane, but not for a low wing
plane. My friend had been taught never to bank too much in the pattern because
of the stall risk, I think. Yet us glider guiders are taught exactly the
opposite. Maybe since we fly the pattern so much closer to stall speed?


Jim Vincent
CFIG
N483SZ


I think many instructors don't like to contemplate a student pilot in
a low, slow, steeply banked turn in an aircraft with low aspect
ratios - such as most simple, powered aircraft. Low aspect ratio
means relatively high drag, thus relatively greater airspeed decay, at
a given AOA, including the relatively high AOA likely in slow, steep
turns.

The argument I've heard for the safety of steeper bank angles is
that the pilot is less likely to make the anxiety-forced error of
thinking the aircraft can be hurried around its turn by the liberal
application of pro-turn rudder: a skidded turn which produces it own
pitch and bank effects that can lead to a stall/spin.

Gliders, with their higher aspect ratio wings, suffer less drag, thus
less airspeed loss, a a given AOA.

illspam (Jim Vincent) wrote in message ...
The reason is, actually, pretty simple: power planes have god-awfull
visibility; if you bank too steeply you lose visual contact with a key
part of the pattern.

Tom, that makes sense to me for a high wing plane, but not for a low wing
plane. My friend had been taught never to bank too much in the pattern because
of the stall risk, I think. Yet us glider guiders are taught exactly the
opposite. Maybe since we fly the pattern so much closer to stall speed?


Jim Vincent
CFIG
N483SZ
illspam

I never bank *too much* in airplanes. In the pattern I use at least 30
deg, more for a high wing with a green house because that gives a good
view into the turn.

The view into the turn varies greatly for high wing airplanes. In a
182 leaning forward gives tolerable vizibility. In an Aeronca Chief
you can't see into the turn at all. That's why competent pilots will
raise the wing before starting the turn.

I don't think I flew any power plane with the view into the turn as
bad as from the 2-33 back seat!

I don't believe visibility is the reason some airplane pilots use
shallow banks in the pattern. I'm also not convinced that gliders fly
closer to stall speed in the pattern. I think it's just that some
airplane pilots were taught by instructors that didn't know any
better.

Andy

The PTS for the SEL rating requires the demonstration of steep turns,
and this maneuver is flown on virtually every check ride. I believe
that the main reason for "gentle" turns is a cultural and training
issue. Power training almost always considers the passenger in the
aircraft--something which is normally not a major issue in soaring.

Frankly, most true passengers are not comfortable in bank angles
greater than 30 degrees. A second MAJOR issue is the continuing
training toward the instrument rating. In actual instrument
conditions turns are normally accomplished at "standard" rate--a
gentle bank. This provides less chance for the pilot to loose control
while flying only with reference to instruments.

An often heard comment from the CFI during the training of a
commercial student is that when he gets his first commercial job his
performance will be judged by the smoothness of his landings
(regardless of winds, etc) and not spilling the president's drink in
the back.

Just some thoughts--

Skip Guimond