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Terrance
60 degrees of bank with 100 kias or more isn't close to a stall AOA. I don't have an AOA indication (yet), but I can feel it in the stick long before the wing fully stalls (long before equals 5+ knots). In my practice sessions, the most important parameter is the airspeed. I take a few moments to establish the glide speed before I do anything else. In this situation "speed is life".
The 60 degrees of bank is really just a wag. What I mean is that my bank angle is well under max performance. It is very hard for me to do this on the edge of a stall -- too many things for my brain to handle. In practice, a more modest bank, like about 60 degrees, is a lot easier to manage and you still get a marvelous turn rate with pretty close to minimum altitude lost for a 180 degree turn.
I've spent a fair amount of time flying at max performance with high AOA. I don't do it a high g load in my LNC2, but I do a pretty aggressive slow flight exercise (at altitude) in an effort to make coordinated flight second nature. However, when I've tried this as a technique to return to land, it's just too many ducks to line up at the same time.
Bill
To: lml@lancaironline.net
Date: Thu, 15 May 2008 14:27:03 -0400
From: troneill@charter.net
Subject: [LML] Re: Crash, fueling nozzles and training
Bill, right. Practice the
procedure. How do yoou know how close your wing is to its stall
AOA
Terrence
L235/320 N211AL
----- Original Message -----
Sent: Wednesday, May 14, 2008 05:38
PM
Subject: [LML] Re: Crash, fueling nozzles
and training
I practice these simulated engine failure turns
from time to time. I'd far rather land on or parallel to the runway than in
the whatever off the ends of the runway. There is a big difference between a
maximum performance turn at 100 KIAS and a 60 degree bank turn. My experience
suggests that the turn rate is so fast at max performance, that timing the
rollout becomes a problem. Max performance puts you on the edge of a stall, so
brain overload is a problem too. However, a 60 degree bank produces a very
brisk turn rate without overtaxing my brain. I can still hold my 100KIAS and
time my rollout perfectly.
To reiterate:
1. Max performance turns at
low altitude suck.
2. 60 degree bank turns are easy if you maintain your
airspeed.
3. Practice, or don't plan to do it for real. The key things are
to maintain your airspeed and keep the ball in the middle.
Almost all
say they'd land "straight ahead". Almost all attempt to return to the airport
when it actually happens. The one's who don't practice often
die.
To: lml@lancaironline.net
Date: Wed, 14 May 2008 11:35:42 -0400
From:
tom.gourley@verizon.net
Subject: [LML] Re: Crash, fueling nozzles and
training
I can't dispute the results shown in the video,
but I gotta wonder. I understand that a steep bank with low airspeed
results in a high turn rate, i.e. completes the turn in the least amount of
time, but it leaves no margin for error. In a real engine out
situation, high pucker factor, probably distractions, maybe some
turbulence, lots of adrenaline, is a 60 degree bank with the stick
pulled back so that you're getting some stall buffeting really a good
idea? I don't think so; especially not in a Lancair, and probably
not in several other types of aircraft. A few years ago I watched the
pilot of a Mooney 231 attempt to make a steeply banked turn to a runway
after loss of power at low altitude. (Yes, it turned out to be fuel
exhaustion.) He was trying to turn a total of 120 - 135 degrees.
He had turned about 90 degrees when the right wing and nose dropped
noticeably; a stall-spin entry. He stopped the rotation
immediately with opposite rudder but was too low to
fully recover. The impact was fatal. I think an off airport
landing with the aircraft under control would always be better than an
uncontrolled descent.
Yes, I realize an AOA would help tremendously
in this situation, assuming the pilot isn't completely paniced and is
capable of flying the AOA accurately. Training and practice sounds
like a good idea.
Tom Gourley
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