Winch Launch Fatality
At 02:41 23 June 2009, bildan wrote:
Might I ask that you actually read what I wrote before correcting me. What
I said is exactly what you have said but in two or three lines.
On Jun 22, 6:15=A0pm, Don Johnstone wrote:
Much has been said and written about winch launch failures and here is
my
"Guide to Surviving a launch failure"
Launch fails
1 Pitch the nose down, at least approach attitude - snip
I have to take issue since anyone following this advice might/will get
hurt.
Rubbish
If you stop the pitch down at 'approach attitude' from an initial
attitude of 30 - 45 degrees nose up, you will be stalled - the nose
must be pushed far below 'approach attitude" to achieve prompt
airspeed recovery.
I said at least approach attitude, not stop at. "at least" means more
may be needed but it should never be less.
This is easy to demonstrate without a winch. At an altitude that
allows safe spin recovery, zoom up at a 45 degree nose-up attitude.
When the airspeed drops to 65 knots, pretend you have a rope break and
push over to 'approach attitude' and stop the pitch down there. Note
the airspeed - it will be around 20 knots. If you turn you will
spin. This is a classic killer on a winch.
I then said, ask the question is the speed at least approach speed only if
the answer to this is yes do you go to stage two which considers turning
only after considering a landing ahead.
There is no counting involved, no waiting, just checking to see if the
relevant conditions apply to allow the procedure to move on.
It is even better to demonstrate off a simulated launch failure and the
more you do the better.
I agree that starting a turn before the airspeed has increased is very bad
news which is why I emphasised that you do not even make the decision
between landing ahead and turning, let alone doing it until the airspeed
is up.
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