AOPA Stall/Spin Study -- Stowell's Review (8,000 words)

"Wayne" writes:

Since the airspeed indicator (pitot tube) is pointed the same as the
wing, then "indicated airspeed" does mean something. For instance,
if you were to put the wing at a 90 degree AOA to the relative wind,
then the airspeed would also read nothing or almost nothing correct?

So I agree that airspeed doesn't matter, but indicated airspeed
does.

His point was that the stall speeds marked on the ASI (Vs and Vso) are
applicable only at 1 G, maximum gross weight, and the appropriate
flap/gear configuration. That's why an angle-of-attack indicator
would be nice.

If you're doing anything that increases the G-load on the plane, like
turning or pulling up from a dive (i.e. anything that presses your
behind into the seat), the stall speeds will be higher; if the plane
is loaded below maximum gross weight, the stall speeds will be lower;
and so on.

It's a bit of an overstatement to say that stall speeds don't matter,
but you do have to take them with a big grain of salt. Let's say that
you have just recovered from a stall or spin and are now in a dive
heading quickly towards the ground. If you pull up hard, you might
stall the plane at close to double the Vs marked on the ASI.


All the best,


David

"David Megginson" wrote in message
...
His point was that the stall speeds marked on the ASI (Vs and Vso) are
applicable only at 1 G, maximum gross weight, and the appropriate
flap/gear configuration. That's why an angle-of-attack indicator
would be nice.


Well, in a way, the airspeed indicator IS an angle-of-attack indicator.

--
Chris Hoffmann
Student Pilot @ UES
30 hours

"Chris Hoffmann" writes:

His point was that the stall speeds marked on the ASI (Vs and Vso) are
applicable only at 1 G, maximum gross weight, and the appropriate
flap/gear configuration. That's why an angle-of-attack indicator
would be nice.

Well, in a way, the airspeed indicator IS an angle-of-attack indicator.

It's related to angle-of-attack, but note all the cautions in the rest
of this thread. It's definitely not the same thing (that's why you
see AOA indicators in some military and aerobatic aircraft).


All the best,


David

On Mon, 01 Sep 2003 20:40:51 GMT, "Chris Hoffmann"
wrote:

"David Megginson" wrote in message
...
His point was that the stall speeds marked on the ASI (Vs and Vso) are
applicable only at 1 G, maximum gross weight, and the appropriate
flap/gear configuration. That's why an angle-of-attack indicator
would be nice.


Well, in a way, the airspeed indicator IS an angle-of-attack indicator.

I've seen this
The airspeed indicator is an airspeed indicator ONLY. It is not, and
should not be thought of as, ANY sort of AOA indicator. If you fly
long enough, this will kill you.

Stall AOA, for example, is a constant. The airspeed occuring at the
stall AOA can and will vary, depending on wing loading resulting
primarily from the weight loaded into the aircraft or loads imposed by
maneuvering the aircraft.