Question for the MEI's

skysnake said:
I'm not a GA MEI however I am a Part 121 check airman for a major airline flying the MD-80. We occasionally get to do actual "pilot trainers" in the real airplane. I can tell you the quickest was to get terminated from my company would be to actually shut off a fuel lever to simulate an engine failure! I actually cannot imagine ever needing to do this.

I understand the need to feather an engine and restart it for training but this should be done so as both the student and MEI are very clear about what is taking place. It should be briefed and done at altitude with a contingency plan if things don't go as planned. Simulating an engine failure by any other means than pulling a throttle to a zero thrust setting is crazy and wouldn't take place in my cockpit.

Chris
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Your post is somewhat contradictory. On one hand, you say you understand the need to feather an engine and restart it, but on the other you say that the only way of simulating an engine failure should be to retard the throttle.

There is no better way to simulate a real engine failure than by turning off the fuel on an engine. The student doesn't suspect it, and as long as the weather conditions are conducive to keeping the aircraft aloft on one engine and there is an airport nearby, I see it as a non-event really.

Even if the good engine were to fail, there should be plenty of altitude to restart the engine with the fuel cutoff. If not, you can still do what all of us single engine guys do and put it down in a field.

Just so you know as well, I have ran this procedure by 3 DPEs that we use. Two are retired Army pilots, one of which retired from American, as well. The other is retired FAA. All 3 of them do the same thing to simulate a failure at altitude.
 
KSCessnaDriver said:
Here is the main reason I asked about this fuel selector issue. I was talking to some guys who were very worried about getting air in the fuel lines by shutting the fuel selector off. I didn't think this would be an issue, because you could always turn a fuel pump on, to push the air through the line, and you'd get the fuel going again. correct?
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Have you ever run a tank dry on a single? Does the same thing to the motor, basically. The fuel flow indicator will bob a bit, then rapidly move toward a high fuel flow indication (because the pressure is dropping off, so the flow rate is dropping off as the more flow you've got going, the higher the pressure). The engine might surge once or twice, then it will die off completely, and will show something around 1500RPM or so depending on your speed. The air in the fuel lines doesn't really do anything. Most of the time, even though the failure checklist is something like "SWITCH TANKS, BOOST PUMP ON, MIXTURE RICH, ALTERNATE AIR ON" all you need to do is switch tanks. To speed up the process you click on the boost pump, and enrichen the mixture. That being said, at 1500RPM, the engine driven fuel pump is still going to be adequate enough push the air through the motor eventually.

A lot of older POHs say things like, "If it is desirable to run a tank dry fully before switching tanks then..." That's taken out of some newer POHs, probably for liability reasons. In piston birds, I don't think there'd be any problem with it, I'd be wary of shutting down a turbine bird at altitude, because if you're not careful when you start back up you could have some temp out problems restarting in the thinner air, but some motors don't even have a problem with that if procedures are followed correctly. They shut em' down on the herc and on P3s to cross the pond all the time.
 
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