Gary L. Drescher wrote:

[snip]

The problem is that there's no such speed. Say you're flying a plane whose
Vs is 50 knots. Under a range of ordinary circumstances, the plane's
flaps-up stall speed could be as low as 45 knots or as high as 75 knots. A
plane stalls at a specific angle of attack, not at a specific airspeed. A
primary student who expects the contrary, or who does not understand how
airspeed relates to angle of attack under different circumstances, has no
good way to anticipate when the plane will stall.

Even when a primary student get their hands around the notion that the
wing can stall at any airspeed, they tend to equate angle of attack with
pitch attitude. They seem to grok "relative wind" on the ground but the
concept seems to skitter out the storm window in flight.

I dunno. With a primary student there's (initially at least) a thin
line between providing enough information and providing too much. Much
of what we do as aviators involves controlling AOA, but if we start
talking about AOA too early we risk the possibility that some people
will overload and bail; if we put it off for too long we end up with
people who never quite understand pitch/power, chase the elevator trim
all over the sky and describe sine waves on the glide slope.

It's a pity that all of those nifty AOA indicators are restricted to the
experimental fleet. Gluing them onto the wings of the 150s, 172s and
PA24s down at the flight school would go a long way toward demystifying
this stuff for people.

--
Chris Kennedy

http://www.mainecoon.com
PGP fingerprint: 4E99 10B6 7253 B048 6685 6CBC 55E1 20A3 108D AB97