From: "Marvin Kaye" <marv@lancaironline.net>
Subject: Re: Stall recovery and spin avoidance
To: lml
Date: Sun, 07 Jul 2002 14:38:43 -0400
Message-ID: <web-1620733@logan.com>
In-Reply-To: <20020707134009.1152.qmail@web12506.mail.yahoo.com>
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Posted for Jim McIrvin <pilot195@rocketmail.com>:

<<in your opinion did the full aft stick stalls in the USAF help the pilots?? 
>>

First, we need to acknowledge that there are significant differences in the 
aerodynamics of the "straight" wing (e.g., Lancair) and the highly swept wing 
of the T-38.  So a pure comparison of characteristics, benefits, etc., is not 
possible.

However, parallels about the benefits of training are possible.

The aft stick stall is taught (more accurately:  "demonstrated") for a couple 
reasons.  First, to allow the student to learn the feel of the aircraft 
(increasing buffet) as the AOA increases to, and beyond, stall.  Second, 
(perhaps most importantly) to demonstrate that the aircraft will recover once 
the aft-stick is released & AOA is reduced below critical.  No power is added. 
  Of course, this uses a lot more altitude than using full power!  Some of us 
also show a third point (not applicable to the LNC's!), which is that the 
pitch picture in the 'stabilized' full aft stick stall is similar to that seen 
on final approach - a/s is a little low (15 knots), and the nose appears about 
3-4 deg low.  But the sink rate is in excess of 6000fpm down (6K is the limit 
of the instrument).

Regarding use of ailerons during stall recovery - remember the basic aero you 
were taught during private pilot ground school.  The down-deflected aileron 
has a drag component of lift that is a function of the AOA and the deflection 
of the aileron (simplistically stated).  A common "reactive recovery" I see in 
pilots who are not comfortable in the stall arena is to throw full-aileron 
deflection in in a (futile, usually) attempt to level the wings.  Doing this 
while the aircraft is near AOAcrit virtually guarantees a stall on the lower 
wing just as you effectively have thrown a big drag parachute behind that 
wingtip (yaw).  

I am not saying aileron cannot be used.  But it needs to be used AFTER 
reducing AOA and the rudder must be used to keep the ball centered.  

Used together, they work well.

:-)

Jim McIrvin
210-275-7780
pilot195@rocketmail.com
Lancair instructor