Mailing List lml@lancaironline.net Message #43312
From: terrence o'neill <troneill@charter.net>
Sender: <marv@lancaironline.net>
Subject: Re: [LML] SUMMARY OF LANCAIR ACCIDENTS IN NTSB DATABASE
Date: Thu, 02 Aug 2007 13:52:10 -0400
To: <lml@lancaironline.net>
Hi Bill,
 
On the LML you asked: What percentage of those 24 planes had AOA indicators, and what is the percentage in the entire fleet, preferably by model?
Judging from the number of Lancairs at OSH that did not have  AOAs, do you think 10%, if that many of the 24, had AOAs? Your inference seems to be that if there is not complete data, the argument is useless... but we all deal capably with generalities every day... I'm just saying that the 24 fatal stall-spins could have been  avoided if the pilots had an AOA indicator and practiced slow-flight with it, ,, instead of being 'angle-blind'. 
I've noted from comments on the LML that one problem here is that many (not all) Lancair pilots are very wary of stalling their Lancairs.
 
You commented: While AOA is a useful tool, I am not convinced that having AOA and using it under normal conditions will immunize you from a spin under abnormal conditions.
I have to wonder whether you have  evaluated them by flying with an AOA, particularly for an hour or so in slow flight, the usefulness of an AOA?  I've been flying with then since 1964.  As to spins, they can only result from stalls, almost always after the incipient phase -- the first two turns wherein the plane unstalls itself twice -- and wherein an AOA indicator can  show you exactly at what angle your wing is working relative to its stall angle, and exactly how much nose-down you need to unstall it.   After the incipient phase, spin  recovery itself depends on the aerodynamic shape of the plane and the mass distribution.
 
Your last comment: If an AOA systems fails in a non conservative way it could induce an accident that would not otherwise have happened.
If anything critical fails it could induce an accident.  To check your AOA you just nibble at a stall.  Takes a few seconds.
Learning to fly is learning habits and information, the teachers say, 21 times.  And we're then reluctant to go through 'unlearning' that our wings stall at an ANGLE ... perhaps because the FAA still insists we talk about a plane's 'stall speed', even though the wing can be stalled from 1 mph to Va, maneuvering speed and G. 
Flying with an AOA is FUN!  It completely eliminates the stall-worry of situations like turning final to a short runway in a loaded plane in turbulent weather on a hot day. 
My pitching AOAs is just trying to spread the joy, and save the lives of some excellent people.
IMHO the best AOAs are indicators that readout in degrees, not little lights or noises. With one like that I have flown for an hour, steep-turning, zooming and so on, just one or two degrees below the wing's stall angle, and never stalling.
So I say -- try it, Bill.  You'll like it.
Terrence
L235/320 N211AL 
 

terrence o'neill <troneill@charter.net> wrote:
Jeff,
 
Thanks for the Lancair accident update. 
Note that of these 126 Lancair accidents, 54 included fatalities, and 24 of the accidents definitely resulted from a stall/spin --  the last pilot-controllable event before the pilot pulled his wing past its stall AOA and became a doomed passenger.
Note that a wing of a trimmed a/c will not stall unless the pilot pulls the stick back too far, causing his aircraft to pitch up to a stall AOA...
which he unintentionally does because he cannot SEE the realtive wind and his wing's stall AOA.
A sad, unnecessary waste of friends' and families lives, beautiful aircraft, and years of creative work, all for the lack of an inexpensive AOA indicator and a little training to develop habitual use of it.
 
Terrence O'Neill
L235/320 N211AL
 



Regards,
Bill Hannahan


Moody friends. Drama queens. Your life? Nope! - their life, your story.
Play Sims Stories at Yahoo! Games.
Subscribe (FEED) Subscribe (DIGEST) Subscribe (INDEX) Unsubscribe Mail to Listmaster