>Extending your flaps with fixed leading edges increases lift coefficient
>but the angle of incidence becomes smaller, draw a line from l/e to t/e
>to see the chord at any given point and configuration and then hold it
>against the relative airflow to see incidence.
>Extending leading edge devices such as slats or l/e flaps increases the
>angle of incidence again given a steady pitch angle.
>So thats what you get, a dramatic change one or the other way in pitch
>required to stall at a given speed when extending one or the other.
This was one of the basic criteria of the design of the Europa wing. Don
Dykins' genius again! The first thing Ivan discovered in the early test
flying, (after the discovery that all those years of work had indeed
produced a "Flying Machine",):-) was that simply trimming for 80 kts clean,
then lowering the flaps, produced an immediate change of pitch attitude and
the aircraft slowed to a trimmed 60 kt approach speed with excellent over
the nose view of the ground, no other action required. This meant that
slowing to 60 kts clean and forgetting to lower gear and flaps would result
in such a nose high attitude that the runway would disappear under the
nose, the aircraft is now quietly reminding the pilot that he needs to
engage brain and do something else .
That was the best argument for linking flaps and gear together, it made a
potentially tricky high performance aircraft that much simpler to fly. IMHO
the strategy proved very effective, the only wheel ups (as opposed to gear
collapses) I know of were at the hands of experienced perhaps overconfident
pilots carrying out graceful side slipping approaches.
Graham
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