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Old 31st Dec 2015, 00:32
  #44 (permalink)  
Propjet88
 
Join Date: Oct 1999
Location: Oz
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Myth Busting

Ladies and Gents,

I don't believe it is appropriate to engage in public discussions about this accident (or any other) before the facts are known. However, the "absolute" advice on stalling being given in this thread concerns me and needs rebuttal.

Stick position may be useful as a cue as to approaching stall – but no more than a cue. Just as IAS, airflow noise, ineffective (“sloppy”) controls, high nose attitude and all the other “cues” that are taught in basic stalling exercises are just cues that may assist - but are not always valid.

Sorry, but the stick position at stall will vary with C of G, acceleration and deceleration rates, flap position, thrust (power) and, in some aircraft, trim position.

In a pure aerobatic aircraft, where aeros are usually performed at a (more or less) fixed fuel load with a given pilot weight and no baggage / freight (fixed C of G), clean aircraft and a set trim position (not normal to trim into aerobatic manoeuvres) the “fixed stall stick position” may be valid. However, for many other cases experienced every day in GA (even a simple C172 with 1 POB versus 3 – 4 POB) the fixed stick position premise is not valid and, if taken as gospel, can be dangerously misleading.

It is just as incorrect to say that an aircraft will always stall at the same stick position as it is to say it will always stall at the same IAS. Both are true for any given set of variables. Change the variables and both are quite wrong.

Stick position is just a cue.

Fly Safe PJ
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