Date: Mon, 8 Nov 1999 22:38:24 -0500
From: Lynda Frantz <LFrantz@compuserve.com>
Subject: Approach Speeds
Sender: Lynda Frantz <LFrantz@compuserve.com>
To: Marve Kay <Lancair.list@olsusa.com>
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I would second Dave Morse's comments and I too would not recommend a single
specific approach speed for the Lancair for the following reasons:
1.  IAS and CAS differences between aircraft of the same type
2.  Non-linearity  IAS CAS errors between aircraft of the same type
3.  Construction differences between aircraft of the same type
4.  Airspeed indicator instrument errors between certified IAS indicators
5.  Weight differences 
6.  Bank differences
7.  Turbulence
8.  CG differences 
8.  Pilot technique

At higher gross weights, steeper bank angles, in turbulence, forward CGs,
and in higher "G" maneuvers, the stall speed will increase and your
approach speed should increase too in order to maintain a constant margin
above the critical AOA.  The critical AOA is always the same for your
specific aircraft regardless.  My Lancair stalls at 15 degress AOA no
matter what the weight, bank, etc. but I can stall it at any IAS.  

If you really understand this concept, you will also agree that I can fly
my Lancair 360 at twenty (20) knots without it stalling.  In fact, you can
fly all the way down to one (1) knot without stalling if the wing is
unloaded enough and the AOA remains less than the critical AOA.  Guys like
Dave incorporate this below "stall speed" flying technique in their
aerobatic routines.  

Nearly one half of our Lancair fatalities to date have resulted in part
from exceeding the critical angle of attack.  This percentage is typical of
all experimentals.   Recovery from Lancair spins require considerable
altitude (thousands of feet). Lancair spins into the ground have proven to
be 100% fatal. 

If you are flying all of your approaches at a fixed IAS, you are not
getting it!  And shame on the FAA who have been the principle conveyor that
IAS is what keeps us flying.    It's AOA!!!
  
Jim Frantz                 
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