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Old October 25th 07, 10:47 PM posted to rec.aviation.soaring
Chris Reed[_1_]
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Posts: 46
Default Polar with spoilers extended?

bagmaker wrote:
I have to add my thinking, open to scrutiny.
1- whatever needs to be done to get the a/c to an acceptable landing
position above and before the field needs to be done early, to minimise
ground effects. (theoretically, if this is adhered to, the problems
wouldnt eventuate, as the pilot would have noticed his/her extra
altitude before arriving at final and modified the curcuit to suit.)


Good point. No-one has mentioned using airbrakes on the base leg, or
even the downwind leg. I often do this if the sink is less than I
anticipated or I hit lift. Once a pilot has some experience it's really
easy to see at this stage if you will be too high, and losing the excess
height early makes the last part of base and the approach much easier
than if you leave all the excess height to be lost in the approach.

I recall that when being trained, I was told not to use airbrakes until
I'd turned finals (though also that in post-solo training it was pointed
out to me that I could now break this rule).

Is it possible that we are too heavily conditioned not to use airbrakes
before the final turn?

In my Open Cirrus I'd rather turn finals a *little* too low, as if I fly
the first part of the approach without brakes I'll soon intercept the
approach funnel. Turning too high is always more difficult. Note that in
a K8 the opposite is true - too low might not be fixable and losing
height is easy (and often not optional!). One of the points which comes
out clearly from this thread is that the answers are very glider-specific.

So I guess my preferred answer is:

0. Lose the excess height before making the final turn, in whatever way
works for you.

[PS For those blessed with a tailchute, I can highly recommend
practising opening the tailchute towards the end of the downwind leg. If
you need it for a real field landing, the approach is too late - what if
it fails to deploy? The feeling of despair as you are clearly too low is
balanced by the elation when you realise that you will make the field
after all. Anyone trying this will need to fly a curved path from end of
downwind to touchdown, as a formal circuit is *far* too scary and will
probably leave you short.]