Landing Techniques. Apparent differences between UK & USA

[Steve Hopkins]

I'm promted to ask a question having read the postings
regarding the different views expressed, in another
thread, regarding the wearing of parachutes in the
UK and USA.
When, as a UK pilot on holiday, flying in the USA a
couple of years ago, the CFI demonstrated his preferred
landing technique which involved progressively reducing
airbrakes as one approached the ground. This gave rise
to very prolonged 'hold-offs' and touchdown at the
stall. Was this a local quirk? Would appreciate the
views of those more qualified than I on the pro's and
con's of such an approach.
For my own point of view, it struck me that this American
technique made spot landing more difficult. Also, I
was concerned that there was a prologed period of very
slow flying close to the ground. Any thoughts?

[Bill Daniels]

"Steve Hopkins" > wrote in
message ...
> I'm promted to ask a question having read the postings
> regarding the different views expressed, in another
> thread, regarding the wearing of parachutes in the
> UK and USA.
> When, as a UK pilot on holiday, flying in the USA a
> couple of years ago, the CFI demonstrated his preferred
> landing technique which involved progressively reducing
> airbrakes as one approached the ground. This gave rise
> to very prolonged 'hold-offs' and touchdown at the
> stall. Was this a local quirk? Would appreciate the
> views of those more qualified than I on the pro's and
> con's of such an approach.
> For my own point of view, it struck me that this American
> technique made spot landing more difficult. Also, I
> was concerned that there was a prologed period of very
> slow flying close to the ground. Any thoughts?
>
>

Despite many efforts, US flight instruction in gliders is far from
standardized. I have of heard the technique you encountered and disapprove
of it for the most part. Changing the amount of spoilers deployed while in
the flare is inviting trouble - not to say never do it, just expect it to be
tricky.

Many CFI-G's have never flown a glider cross country or, for that matter, at
any other locale than those with a long paved runways. Getting the glider
down and stopped in the shortest distance is not something they have thought
about very much.

I prefer a fairly steep glide path to a flair with spoilers left where they
were in the approach followed by a low-energy touchdown and a short rollout.
Pretty much what I would expect to do in an off-field landing.

Bill Daniels

[Pete Brown]

"Steve Hopkins" > wrote in
message \
> When, as a UK pilot on holiday, flying in the USA a
> couple of years ago, the CFI demonstrated his preferred
> landing technique which involved progressively reducing
> airbrakes as one approached the ground. This gave rise
> to very prolonged 'hold-offs' and touchdown at the
> stall. Was this a local quirk?

yes...and not a particularly good one either INHO.

[MikeYankee]

>involved progressively reducing airbrakes as one approached the ground...

Sounds kinda flaky to me. I guess the key thing is what "progressively" means,
and at what point during the approach the reduction in spoilers is started.

Spoilers SHOULD be reduced in the last few seconds of the approach, as touching
down in the proper landing attitude without spoilers gives the lowest touchdown
speed -- especially important for unflapped ships and off- or rough-field
landings.



Mike Yankee

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[Judy Ruprecht]

At 19:00 08 February 2004, Bill Daniels wrote:
>I prefer a fairly steep glide path to a flair with
>spoilers left where they
>were in the approach followed by a low-energy touchdown
>and a short rollout.
>Pretty much what I would expect to do in an off-field
>landing.

Unless, of course, you're flying a 2-32 using full
dive brakes on final. Holding this configuration through
the flare, you will impact terra firma more abruptly
than you thought possible and it may be weeks before
you can walk upright again. This may, however, be preferable
to running into an obstacle.

Please to note proper spoiler/dive brake use, proper
touch-down attitude and short or off-field landing
techniques will vary with the aircraft, the situation
and the available alternatives.

In a preachy mood...

Judy

[Eric Greenwell]

MikeYankee wrote:
>>involved progressively reducing airbrakes as one approached the ground...
>
>
> Sounds kinda flaky to me. I guess the key thing is what "progressively" means,
> and at what point during the approach the reduction in spoilers is started.
>
> Spoilers SHOULD be reduced in the last few seconds of the approach, as touching
> down in the proper landing attitude without spoilers gives the lowest touchdown
> speed -- especially important for unflapped ships and off- or rough-field
> landings.

I think SHOULD is too strong a statement. Many gliders become very
sensitive to pitch control with spoilers closed, and any value from a
reduction in touchdown speed is likely to be negated by ballooning and
subsequent hard touchdown. This is especially true of all the flapped
gliders I've flown when landing with positive flap (the usual case);
it's probably easier to do on an unflapped glider. If you can do it
under the stress and uncertain conditions of field landing, I'm
impressed, because I know I'm very unlikely to do so, based on thousands
of landings on airports and dozens in fields.

Another situation where it would be a poor choice is a short field where
the need to stop as quickly as possible is important. Floating along is
not a good idea when a fence is approaching!

--
-----
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Eric Greenwell
Washington State
USA

[Bill Daniels]

"Judy Ruprecht" > wrote in message
...
> At 19:00 08 February 2004, Bill Daniels wrote:
> >I prefer a fairly steep glide path to a flair with
> >spoilers left where they
> >were in the approach followed by a low-energy touchdown
> >and a short rollout.
> >Pretty much what I would expect to do in an off-field
> >landing.
>
> Unless, of course, you're flying a 2-32 using full
> dive brakes on final. Holding this configuration through
> the flare, you will impact terra firma more abruptly
> than you thought possible and it may be weeks before
> you can walk upright again. This may, however, be preferable
> to running into an obstacle.
>
> Please to note proper spoiler/dive brake use, proper
> touch-down attitude and short or off-field landing
> techniques will vary with the aircraft, the situation
> and the available alternatives.
>
> In a preachy mood...
>
> Judy
>
It's OK, Judy. You made a good point.

Bill Daniels

[MikeYankee]

>I think SHOULD is too strong a statement.

I don't think it's too strong, but perhaps too general. It depends somewhat on
conditions. If it's gusty, keeping some spoiler on is wise because quickly
cleaning up the wing as you lower the nose may be the best way to fly out of a
wind shear; if your spoilers are already retracted and you're still 20 ft high
a few knots above stall speed you may arrive precipitously. On the other hand,
if you're coming in over an obstacle into a short field, a firm impact with
spoilers is preferable to floating into the trees at the other end. On the
third hand, if you're landing in a long field whose surface is unknown and
possibly rough, you're better off making the glider alight at the lowest
possible speed, which means no spoilers.

I contend that in calm conditions, you should touch down (flapless gliders)
with a clean wing and a slightly tail-low attitude.

When I see people float and overshoot it's often because they have too much
speed and too much spoiler on short final and roundout. Abruptly closing the
spoilers in this situation is just like adding power in an airplane.








Mike Yankee

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To reply, delete everything after "com".)

[Robert Ehrlich]

Bill Daniels wrote:
> ...
> Despite many efforts, US flight instruction in gliders is far from
> standardized.
> ...

Thanks to many efforts, french flight instruction in gliders is
(or at least should be) standardized. The standard say students
should first learn to keep the airbrakes during roundout at the
half efficiency position they had during the last part of the final,
and later learn to do the rouddout while progrssively extending the
airbrakes to their maximum. Although this does not provide the lowest
possible speed at touch down, this provides the highest possible decay
in speed and this is the important thing as well for minimizing the
length of the ground roll as for avoiding to bounce.

We don't have Schweitzers which would defeat this strategy. The local
equivalent in terms of national singularity would probably be the
Bijave, which works this way.