Kim West:
Clinton - well said - another scenario not discussed is that from a simulated engine failure, using the power lever, and having the aux boost pump on, particularly on PA 31 types, there is a very real chance that the engine will not accelerate due to the over rich mixture when power is applied.
The engine will not accelerate, and will tend to stall (ie not do anything) other than run rough, coff, farrt, etc - everything except supply power. I make mention of this from first hand experience. To the extent that, although the pre take off check list calls for "pumps on", I do not turn the pumps on until the engines have achieved at least 20"of MP. The alternative is to run the very real risk of being 1/4 way down the runway, and still be waiting for the engine(s) to come up to t/off power.
Too much fuel can have the same effect as no fuel, ie - the engine floods, the fire goes out, no power.
Your comments??
My simple observation is that if the engine is coughing and farting on application of T/O power, and I'm doing everything in accordance with the POH. then I'm aborting and going back to the hangar, not inventing my own procedure to "get around" the problem. Once at hangar, I will ask an older and wiser head why the engine is misbehaving....
Twice, it's been linkages (fuel injected). Once, carb ice. The former issues were fixed by screwdriver or replacement. The latter by technique. I'm prepared to wear "It always does that, and this is how you fix it" when immobile on the ground, such as leaning to clean a plug. As a ham fisted pig ignorant pilot, I am not flying with little "glitches" as i already have enough to do.
Clinton:
My only (inexpert) input to this thread relates to the sub-set of the discussion about the comparative safety of simulating an engine failure on a GA piston engine by pulling the throttle versus pulling the mixture. The ‘Old Wives Tale’ seems to be that pulling the mixture is necessarily less safe than pulling the throttle. (As an aside, my view is that the phrase ‘Old Wives Tale’ is a little sexist these days. I’d probably opt for: ‘Near-dead-white-male pig-ignorant self-proclaimed expert tale’, but the acronym’s a little clunky and I’m probably being a little unkind.)
You are entitled to your opinion. Mine is that I would prefer the fuel to be flowing, the carb float to be floating, or the diaphragm to be diaphragming, the jets to be jetting and some pitiful form of combustion to be going on in each and every cylinder. The fire can then hopefully restored by the traverse of a butterfly valve through about Eighty degrees of rotation.
To do otherwise conjures images of an Eskimo about to demonstrate his fire lighting skills to his colleagues in mid winter by first extinguishing their fire, but call me old fashioned and pig ignorant. I don't really want to demonstrate that the mixture control is working each time I do a PFL, I just want to do the PFL.
Anyway, this is all off topic. There should be ONE way and ONE way only for an Australian FOI to require a particular procedure to be performed on a particular make and model of aircraft, or if there are Two or more ways, it must be spelt out that it is the OPERATORS choice which one gets used.