Slip to landing on PPG practical test

Andreas Maurer wrote:
I bet that this FAA examiner has never done that either in a modern
glider with an L/D over 30 - otherwise he's know that it's going to
take a runway of *at least* 6.000 ft and a sideslip to *very* low
altitude to be able to land without using the airbrakes.

Considering the L/D is increased by ground effect, even doubled
according to some, you have a point.

But even with an L/D of 1:80, if you sideslip to 1 m off the
ground you'll only float 80 m, about 260ft, from there, and
quite a bit less with a headwind.

Agreed that the precision needed to slip it down that low
is probably too much to ask of someone just about to get their
licence, but it does not sound too crazy as an exercise at
a more experienced level. In case you get it wrong you should
of course be ready to abort and pull the brakes well before
there is any danger of going off the far end.

Cheers CV

On Sun, 31 Oct 2004 20:52:15 +0100, CV wrote:

But even with an L/D of 1:80, if you sideslip to 1 m off the
ground you'll only float 80 m, about 260ft, from there, and
quite a bit less with a headwind.

You are correct, but the problem is not the L/D in ground effect, but
the speed. Minimum safe approach speed is about 50 kts, touchdown with
the tail wheel first in ground effect will happen at maximum at 35 kts
- to bleed off 15 kts in ground effect takes amazingly long - I'd
estimate about 3.000 ft for the ASK-21.

Of course you can put her down with force onto the nose wheel at
higher speeds, but this is probably going to result in an PIO.


Agreed that the precision needed to slip it down that low
is probably too much to ask of someone just about to get their
licence, but it does not sound too crazy as an exercise at
a more experienced level. In case you get it wrong you should
of course be ready to abort and pull the brakes well before
there is any danger of going off the far end.

Been there, done that, using Ka-8 (landing with sideslip only is
possble if the speed is correct), DG-300 and ASK-21. Neither the 300
nor the 21 could be brought down without flaps on our 1800 ft runway,
altough I was low (3 ft) and slow (50 kts) at the beginning of the
runway.

Sideslipping below 50 ft is hazardous - the slightest mistake while
pulling out of the sideslip might result in an unwanted and hard
impact, not to mention the fact that it's hard to judge the ground
clearance of the lower wing tip. And a final glide from 50 ft with a
fictious L/D of 45 will eat up 2250 ft of the runway, even not
counting the fact that you still have to bleed off your speed.


Sorry - landing with sideslip only is an interesting stunt, but
doesn't have a lot to do with safe flying.


I think it's percetly sufficient to ask for a sideslip down to 150 ft
and then a normal landing with flaps.


Or does the FAA guy in question also demand to fly without another
primary flight control, say, the elevator, if you want to pass his
test?






Bye
Andreas

Judy Ruprecht wrote in message Ask your CFI to have a heart-to-heart with the DE.
If he/she is 'hard over' on slipping all the way to
the ground irrespective of aircraft and airport concerns,
find another DE.

Judy
====================================
I agree with Judy.

Terry Claussen
DPEG AZ

How about reporting this DPE to the FSDO? There is little quality control
on the DPEs if pilots do not report problems. Just because they do well on
their DPE checkrides with the FAA does not make them a good DPE!

"Terry Claussen" wrote in message
om...
Judy Ruprecht wrote in message Ask your CFI to
have a heart-to-heart with the DE.
If he/she is 'hard over' on slipping all the way to
the ground irrespective of aircraft and airport concerns,
find another DE.

Judy
====================================
I agree with Judy.

Terry Claussen
DPEG AZ

I'd only "report" him/her if this request persists to the bitter end.
Perhaps it would be good to take some of these posts and share them with
the DE before your meeting and suggest that while it's part of the PTS,
you have concerns about the safety of such a maneuver. Outright
reporting and subsequently ticking him/her off might be a poor move.
Additionally you can suggest that a no spoiler approach is essentially a
maneuver that is only required if you have an in-flight spoiler failure
and that the pre-flight and "positive" checks should find a control hook
up issue. Furthermore, it's an extremely rare failure.

I've only seen this maneuver attempted once and the CFIG who attempted
to do it flew an L-23 the length of a 5000' runway before going for the
brakes and then moderately ground looping at the end of the roll to
avoid the ditch at the end of the property. Previously he'd instructed
in 2-33s. I would not chose to do it myself.

Paul Lynch wrote:
How about reporting this DPE to the FSDO? There is little quality control
on the DPEs if pilots do not report problems. Just because they do well on
their DPE checkrides with the FAA does not make them a good DPE!

"Terry Claussen" wrote in message
om...

Judy Ruprecht wrote in message Ask your CFI to
have a heart-to-heart with the DE.

If he/she is 'hard over' on slipping all the way to
the ground irrespective of aircraft and airport concerns,
find another DE.

Judy

====================================
I agree with Judy.

Terry Claussen
DPEG AZ

I also live in Idaho and had a different examiner than Wayne. I did
my commercial and CFIG check at the Nampa, ID airport, 2,500 asl and
about 4,700' long runway at that time. I did it in a Blanik L13 too.
I had been forewarned and had practiced this with my instructor and
other mentor pilots even before seeing it in the PPG. I was told to
get it stopped in the first third of the runway. I started it on
downwind and was only a few feet above the ground when I crossed the
beginning of the runway. I did not find it too difficult and in fact
the vis. from the back seat was better in a slip. The big head of the
examiner was out of the way.
Tom
Idaho



"Wayne Paul" wrote in message ...
I took my practical flight test in an L-13 Blanik and was required to land
without the use of spoilers.

When I checked the spoilers on the down wind, the examiner informed me that
they were frozen shut. He also picked a spot on the field where he wanted
me to land. I started my slip prior to turning base and continued it on
final making adjustments as necessary to land on the designated spot.

Driggs, Idaho was the location of the examination. The field is a 6,200
feet MSL and is 7,300 feet long. Safety wasn't a concern. The landing spot
picked by the examiner was 1,000 feet from the approach end. I didn't find
it too stressful; however, I am sure the stress level would have been much
greater on a short runway.

Wayne
http://www.soaridaho.com/

"

CV wrote in message ...
Andreas Maurer wrote:
......it's going to
take a runway of *at least* 6.000 ft and a sideslip to *very* low
altitude to be able to land without using the airbrakes.


While it seems a excessive for a private rating, most pilots can train
to safely and repeatedly conduct this maneuver in considerably less
airport than 6000 ft.! I have done it a lot and some of my friends
could do it consistently. Success requires a very high degree of
speed discipline - even in extremely "slipped" attiudes, a very good
understanding of slips and adverse yaw, and a different mindset
regarding pattern altitudes and shapes. One also must slip to very,
very low altitudes - e.g., through the flair. Sounds bad but it is
not really that bad.

Remember that AS-W12 pilots routinely (1000's of flights) slipped a
50:1 glider to a landing in considerably less than this in extreme
conditions including Appalachian ridge days(Schuemann), wild thermal
days in TX (Scott, Greene) and monster wave days in NV (Herold).

I have landed 100's of flights in glass in Tehachapi, CA without drag
devices. These landings were typically over a 30 ft obstacle at
density altitudes 5000 ft, and ALL stopped in less than 2500 feet.
More than 50 if those were in an AS-W12. Other gliders involved:
AS-K21, AS-W20, AS-W17, G-103, G-102, LS-4, and Caproni (not
recommended!).

Mark Grubb wrote:
CV wrote in message ...

Andreas Maurer wrote:

......it's going to
take a runway of *at least* 6.000 ft and a sideslip to *very* low
altitude to be able to land without using the airbrakes.


While it seems a excessive for a private rating, most pilots can train
to safely and repeatedly conduct this maneuver in considerably less
airport than 6000 ft.! I have done it a lot and some of my friends
could do it consistently. Success requires a very high degree of
speed discipline - even in extremely "slipped" attiudes, a very good
understanding of slips and adverse yaw, and a different mindset
regarding pattern altitudes and shapes. One also must slip to very,
very low altitudes - e.g., through the flair. Sounds bad but it is
not really that bad.

Remember that AS-W12 pilots routinely (1000's of flights) slipped a
50:1 glider to a landing in considerably less than this in extreme
conditions including Appalachian ridge days(Schuemann), wild thermal
days in TX (Scott, Greene) and monster wave days in NV (Herold).

I have landed 100's of flights in glass in Tehachapi, CA without drag
devices. These landings were typically over a 30 ft obstacle at
density altitudes 5000 ft, and ALL stopped in less than 2500 feet.
More than 50 if those were in an AS-W12. Other gliders involved:
AS-K21, AS-W20, AS-W17, G-103, G-102, LS-4, and Caproni (not
recommended!).
I must take issue with that Mark. I am a much less experienced pilot than you,
but let's look at this from my perspective. As safety officer at my club I would
exercise my prerogative of referring anyone who wanted to perform slips into
the flare for any reason to the CFI for review of their permission to fly.

A few comments -
1] I know it can be done, and even reasonably safely.
2] I know it is dangerous to do this in anything with long wings, and we have a
sloped undulating runway with long grass near the runway.
3] Given the remote probability of ever experiencing this I think the standard
way of testing here, is better. Student gets to find airbrakes frozen at some
point in the circuit, and needs to demonstrate decision making, and execution.
(but the landing is carried out normally)
4] Show that you can perform slips, and S-turns and low approaches by all means.
5] Decision making is far more important than demonstrating a dangerous manouever.
6] Experience is less indicative of safety than is attitude, ask someone like JJ
where most of the repair jobs come from.

For what it is worth - My glass experience is restricted to the Std Cirrus and
Grob 103 Twin II. The Cirrus slips if you want her to, but turbulence over the
tail and pitch sensitivity make low slips highly undesirable. The Grob is heavy
and predictable, but roll rate is not exactly electrifying at low speed. In both
cases the extra speed you would be carrying for control would negate any
advantage. Since it does not benefit you, I can't see any justification for
doing something dangerous.

Our club's founder - Dieter Henschell learned to fly in the 1940s. His favorite
demonstration to pupils who insisted on too high approaches was to make a normal
approach in the Blanik and then proceed up the 2km runway with the brakes closed
from around 10m height and 100km/h. All the way reciting in his gentle German
accent, look the speed is X and I am still flying.. Look the speed is now x-5
and I am still flying...
Most students got the point in one. And that was with a Blanik. Tried something
similar with my Cirrus - the only way to get her stopped on tar without brakes
is to be dangerously slow over the numbers 2m up and 80km/h. That is 10kt
above stall. Eventually touched down tail first - a gentle full stall landing
indicating around 60km/h nearly 400 m later. Work it out, effective L/D is
probably around 70, and I have to lose 15-20km/h - that is a fair amount of
energy. My wingtip on the ground has less than one metre clearance, from a 2m
height I only have 3m clearance, over a length of 7.5m - do the trigonometry
that is a serious cartwheel type impact at a slip angle of less than 21 degrees.
The Cirrus does not seem to lose much in a slip of less than 30 or so degrees -
then there is the fence at 1.2m to consider - what am I achieving, other than to
demonstrate my poor judgment by practicing slips into the flare?

Just because it was standard procedure some years ago, with a glider that had
design faults with inadequate drag controls does not mean it should still be
standard practice. The discussion about spin demonstration in the circuit is an
example. Eventually the BGA dropped this after a number of fatal accidents. Why
do people have to die demonstrating something that is marginally useful, and has
so low probability of happening, relative to the probability of injury
demonstrating it?

Imagine a fighter pilot having to demonstrate a successful ejection at each
flight review. Same question, why on earth would you expect that?

On 31 Oct 2004 19:08:54 -0800, (Mark Grubb) wrote:

Remember that AS-W12 pilots routinely (1000's of flights) slipped a
50:1 glider to a landing in considerably less than this in extreme
conditions including Appalachian ridge days(Schuemann), wild thermal
days in TX (Scott, Greene) and monster wave days in NV (Herold).


Ah, the ASW-12...
Unfortunately I never had the chance to fly one - I would have loved
to try this landing technique. Maybe I gte the chance one day - it's a
pity that my home airfield is only 2.000 ft.

I have landed 100's of flights in glass in Tehachapi, CA without drag
devices. These landings were typically over a 30 ft obstacle at
density altitudes 5000 ft, and ALL stopped in less than 2500 feet.

How was your landing technique? As far as I know the recommended
procedure was to put her on the main wheel at relatively high speed
and use the wheel brake to stop her in order to avoid the usage of the
brake parachute?



Bye
Andreas

Here's a radical idea for the ASW-12. Jettison the
canopy, on the theory that it will then fly as if dive
brakes were open. grin

As I recall hearing, the L/D was 28/1 with the drogue
deployed. Are there any still flying? Seems I recall
a concerted effort to remove them from the market in
order to save lives.


At 15:06 01 November 2004, Andreas Maurer wrote:
On 31 Oct 2004 19:08:54 -0800, (Mark
Grubb) wrote:

Remember that AS-W12 pilots routinely (1000's of flights)
slipped a
50:1 glider to a landing in considerably less than
this in extreme
conditions including Appalachian ridge days(Schuemann),
wild thermal
days in TX (Scott, Greene) and monster wave days in
NV (Herold).


Ah, the ASW-12...
Unfortunately I never had the chance to fly one - I
would have loved
to try this landing technique. Maybe I gte the chance
one day - it's a
pity that my home airfield is only 2.000 ft.

I have landed 100's of flights in glass in Tehachapi,
CA without drag
devices. These landings were typically over a 30 ft
obstacle at
density altitudes 5000 ft, and ALL stopped in less
than 2500 feet.

How was your landing technique? As far as I know the
recommended
procedure was to put her on the main wheel at relatively
high speed
and use the wheel brake to stop her in order to avoid
the usage of the
brake parachute?



Bye
Andreas