Landing Techniques. Apparent differences between UK & USA

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

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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