Slip to landing on PPG practical test

Bruce,

I do not think there have been any fatal accidents in the U.K. where a spin
was deliberately entered below 1,000 ft. If you know different, could you
please tell us about it.

I know of one fatal accident where a spin was deliberately started at about
1,400 ft., this was during instructor training and it is known that recovery
was started too low.

The report on the accident last January where both pilots were killed has
not yet been published. However, it is known that the spin was started
above 1,000 ft.

In practice, some clubs and some instructors never did this low spin entry
exercise; the wording in the BGA Instructors' Manual meant that in fact it
was optional, since it was open to any instructor to judge that not all the
caveats were met.

The relevant wording was:
"As this training progresses, it is necessary to introduce _brief_ spins
where the ground is noticeably close. This is to ensure that the trainee
will take the correct recovery action even when the nose is down and the
ground approaching. A very experienced instructor flying a docile two
seater in ideal conditions may be prepared to initiate a _brief_ spin from
800'. A less docile two seater with a less experienced instructor, or less
than ideal conditions, should raise the minimum height considerably."

Unfortunately, there have been many fatalities in the U.K. from an
inadvertent stall/spin entered below 1,000 ft. The belief was that the low
height spin entry exercise, done correctly under the right conditions (type
of glider, C. of G. position, weather etc. conditions, experience skill and
currency of instructor) would help to reduce the number of these accidents.

W.J. (Bill) Dean (U.K.).
Remove "ic" to reply.


"Bruce Greeff" wrote in message
...

snip

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

I haven't tried this manuever myself. I'd be a bit hesitant
due to the airspeed errors in some aircraft in a sideslip, and
the need for excellent airspeed control for ensured success.
Additionally, I suspect the correct airspeed varies enough
with weight that this is another factor to consider, and
is a little beyond the scope of the PPG.

Of course I will try it for fun, but for students I wouldn't
like to have them practicing this solo (when the weight is very different).
I remember trying this in the Katana DA-C1 by not using
flaps, and that the airspeed control needed meant one was at
well less than 1.3 x Vs1...

In article ,
CV wrote:

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



--

------------+
Mark J. Boyd

Mark James Boyd wrote:
I haven't tried this manuever myself. I'd be a bit hesitant
due to the airspeed errors in some aircraft in a sideslip, and
the need for excellent airspeed control for ensured success.

Yeah, I routinely see L23 airspeed errors of -20 kts or more in a full
slip. I emphasize noting the pitch attitude before entering the slip and
maintaining it in the slip. Ignore the ASI.

Tony V.

Tony Verhulst wrote:
Mark James Boyd wrote:

I haven't tried this manuever myself. I'd be a bit hesitant
due to the airspeed errors in some aircraft in a sideslip, and
the need for excellent airspeed control for ensured success.


Yeah, I routinely see L23 airspeed errors of -20 kts or more in a full
slip. I emphasize noting the pitch attitude before entering the slip and
maintaining it in the slip. Ignore the ASI.

Tony V.

Any pot pitot is going to be inaccurate, a 50 deg slip as discussed earlier
means you can only rely on attitude for airspeed.
On my Cirrus anything more than a very modest yaw results in wild airspeed
fluctuations - presumably due to buffeting of the static and the disturbed
airflow over the pot.

One reason why people are suggesting you need extremely good airspeed control
and a little extra speed in case of misjudgement.

Is it possible to stall the aircraft in a full slip? On the two aircraft I have
tried it (at height of corse) I ran out of back elevator before I was able to
stall it. ASK13 and ASK21

I must be missing something.

During a BFR a year or so ago I was asked to fly the
aircraft - a Grob 103 - without the benefit of each
of the controls (one at a time!). The no-airbrake landing
worked out fine. Yes you have to set up a low approach
and use slips, but the key thing for successfully executing
the maneuver is to point the nose at the runway threshold
(or just short) and let the speed build up. Higher
speed plus a sideslip produces a fair amount of additional
drag, even on a 'modern' glider. As I remember, we
got up to about 80 knots, leveled out at about 20 feet
and held the slip to bleed off airspeed until just
before the flare. This way you don't have to turn final
at 50 feet to make the landing spot. I'm not fond of
S-turns on final as I know of at least one high-time
pilot who died in spin doing this.

I'd rather practice all of this ahead of time when
I know I have a backup plan rather than having to do
it perfectly the first time in an emergency. Whether
it should be part of a practical exam for a private
ticket is debatable I suppose, but I highly recommend
that all glider pilots practice for jammed controls
every so often.

9B


At 17:54 31 October 2004, Andreas Maurer wrote:
On Sun, 31 Oct 2004 05:50:43 GMT, 'Roger Worden'
wrote:

I'm preparing for my Private test, and in discussing
it with the local FAA
examiner, he indicated that one item on the test is
a landing with no drag
devices, using only a turning and forward slips. As
he explained it, the
task in the PTS is to demonstrate the ability to land
totally WITHOUT
airbrakes, to simulate a landing wherein the airbrakes
have failed.

This requirement is one of the major bull**** things
I ever had the
pleasure of reading on RAS.

My advice - get some other FAA examiner. This one obviously
doesn't
know anything about gliding.


Throughout my training I've practiced many turning
slips to FINAL APPROACH
(to lose altitude) without airbrakes, but I have always
ended the slip and
landed normally by using the airbrakes.

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.





Bye
Andreas

This discussion--over whether it's more dangerous to practice
something inherently risky or to learn by doing it the first
time--reminds me of checking out as an instructor with a Northeastern
U.S. glider club when I was in graduate school there back in the
1970s. The check pilot had me box the wake in the Blanik and then
asked me to put some slack in the tow rope and take it out gently. I
pulled up a little and then dove slightly to loosen the rope, then
waited for the towplane to climb up while I yawed the glider.

"Now let's put a *lot* of slack in the rope. I'll do the first one."

I watched, fascinated, as the check pilot took us up well over the
towplane, then moved out to the side and dove down until the towrope
disappeared *behind* the glider. We were still aft of the towplane but
I could look out to the side and see the towrope extending past us as
far as I could see.

The proper recovery technique was to stay above and to the side of the
towplane so that as the slack began to come out and you saw the loop
going by you from back to front, you could dive and turn in to match
speeds. The check pilot did this and it actually worked!

I made a couple of tries, the second of which wasn't as bad as the
first. I was *really* happy, though, when it was over. Turns out this
was a standard practical test item required by the local Designated
Examiner (and also high-time glider pilot).

I wouldn't want to be held to it because I can't remember the details,
but I recall hearing years later about a bad accident in that same
area caused by the towrope getting fouled in the elevator or aileron
during such a maneuver.

Some RAS readers must be familiar with this. Is this maneuver still
done? Were there ever any accidents arising from it?

And what's today's thinking about the wisdom of this kind of training?

Chip Bearden
ASW 24 "JB"

There are certainly some things like low altitude spins that are better
approached by teaching spin avoidance. The risks of training are far higher
than any perceived benefit.

Slips to a landing are a slightly different situation IMHO. They are highly
effective and appropriate in low performance/high drag gliders. The problem
is that nowadays, most pilots quickly move to glass.

When a pilot graduates to high performance gliders, different techniques are
required. Landing a 50:1 glider in a small field is a situation where the
spoiler/speed brakes had just better work.

Just what are the chances of dive brake failure? Frozen shut? Very few
glider pilots fly in icing conditions. Forget to connect them? I'd rather
practice assembly checklists and PCC's. If the training is to slip to a
position where the approach can be continued with spoilers, what scenario is
that training for? (Other than the checkride)

There even may be a danger in teaching slips for controlling the approach to
landing. A pilot may subconsciously feel he has a slip available if the
spoilers don't quite do the job and habitually fly high patterns in a
slippery glider until one day he finds that there are really no options
beyond the use of spoilers and pattern adjustments.

Note that I'm not suggesting that slips be removed from the training
syllabus, just that perhaps they should not be taught as a landing aid.
Slips to a landing is just so...20th century.

Bill Daniels


"Chip Bearden" wrote in message
om...
This discussion--over whether it's more dangerous to practice
something inherently risky or to learn by doing it the first
time--reminds me of checking out as an instructor with a Northeastern
U.S. glider club when I was in graduate school there back in the
1970s. The check pilot had me box the wake in the Blanik and then
asked me to put some slack in the tow rope and take it out gently. I
pulled up a little and then dove slightly to loosen the rope, then
waited for the towplane to climb up while I yawed the glider.

"Now let's put a *lot* of slack in the rope. I'll do the first one."

I watched, fascinated, as the check pilot took us up well over the
towplane, then moved out to the side and dove down until the towrope
disappeared *behind* the glider. We were still aft of the towplane but
I could look out to the side and see the towrope extending past us as
far as I could see.

The proper recovery technique was to stay above and to the side of the
towplane so that as the slack began to come out and you saw the loop
going by you from back to front, you could dive and turn in to match
speeds. The check pilot did this and it actually worked!

I made a couple of tries, the second of which wasn't as bad as the
first. I was *really* happy, though, when it was over. Turns out this
was a standard practical test item required by the local Designated
Examiner (and also high-time glider pilot).

I wouldn't want to be held to it because I can't remember the details,
but I recall hearing years later about a bad accident in that same
area caused by the towrope getting fouled in the elevator or aileron
during such a maneuver.

Some RAS readers must be familiar with this. Is this maneuver still
done? Were there ever any accidents arising from it?

And what's today's thinking about the wisdom of this kind of training?

Chip Bearden
ASW 24 "JB"

This discussion--over whether it's more dangerous to practice
something inherently risky or to learn by doing it the first
time--reminds me of checking out as an instructor with a Northeastern
U.S. glider club when I was in graduate school there back in the
1970s. The check pilot had me box the wake in the Blanik and then
asked me to put some slack in the tow rope and take it out gently. I
pulled up a little and then dove slightly to loosen the rope, then
waited for the towplane to climb up while I yawed the glider.

"Now let's put a *lot* of slack in the rope. I'll do the first one."

I watched, fascinated, as the check pilot took us up well over the
towplane, then moved out to the side and dove down until the towrope
disappeared *behind* the glider. We were still aft of the towplane but
I could look out to the side and see the towrope extending past us as
far as I could see.

The proper recovery technique was to stay above and to the side of the
towplane so that as the slack began to come out and you saw the loop
going by you from back to front, you could dive and turn in to match
speeds. The check pilot did this and it actually worked!

I made a couple of tries, the second of which wasn't as bad as the
first. I was *really* happy, though, when it was over. Turns out this
was a standard practical test item required by the local Designated
Examiner (and also high-time glider pilot).

I wouldn't want to be held to it because I can't remember the details,
but I recall hearing years later about a bad accident in that same
area caused by the towrope getting fouled in the elevator or aileron
during such a maneuver.

Some RAS readers must be familiar with this. Is this maneuver still
done? Were there ever any accidents arising from it?

And what's today's thinking about the wisdom of this kind of training?

Chip Bearden
ASW 24 "JB"