It's too early in the morning to laugh like that, but thanks. You're still funny. Very well, let's get on with it.
Guppy..when you cut off the fuel from a windmilling turbine engine...what will the mechanical fuel pump do when it doesn't have fuel to lubricate it?
No long answers...no dissertations on how stupid I am...what does a mechanical fuel pump do when you starve it off fuel.
No dissertations are required: you prove that fact quite conclusively all by yourself.
Do you know what happens when you feather the propeller on a PT6A installation? Do you really believe that the engine keeps rotating, or causes damage? When the engine is shut down, it's shut down. When the engine does windmill, however, when the gas generator still turns, if it's still turning (
do you know anything at all about the PT6A?), the propeller isn't connected to the gas generator. If one has feathered the propeller, one hasn't starved the fuel pump of fuel.
If one shuts down the engine in flight, one hasn't starved the fuel pump of fuel. You do understand, of course, that an inflight shutdown, particularly one using the aircraft manufacturer checklist, doesn't involve starving the pump of fuel, right? Do you understand that shutting the engine down using the fuel control has no effect on the fuel pump, because it's downstream of the fuel pump? You really don't know anything about the engine, or the procedures for operating it, do you?
No need to call you an idiot, mate. You do that to yourself over and over with your comments. Your own commentary is self-indictment. This is why I pointed out that you don't appear to know enough to be embarrassed. I'm embarrassed for you, and if that were all, you'd be little more than a fish in a barrel. The problem we face here is that you claim to be a professional, and are therefore not just innocently ignorant and laughably uninformed. You're dangerous.
At least you would be, if one would push one's self to the edge of reason and believe for a moment that you're who you claim.
Care to answer that? Now if, you have ever been IN CHARGE of an aircraft meaning you are RESPONSIBLE for it....you might think twice about taking it up...on the boss's nickel and shutting down engines for fun...just a thought...
I don't shut down engines for fun. I shoot for fun. I hike for fun. I skydive for fun. I even fly for fun. But I don't shut down engines for fun.
I shut down engines for training. I shut down engines using aircraft and engine manufacturer procedures. I shut down engines from necessity. I shut down engines to test, to teach, to demonstrate, to show, to prove, to save, and to prevent. But never for fun. I just don't see the fun in it.
I never shut them down on my nickle, however. Someone is always paying me. I fly when someone pays me to fly, and when I shut down an engine, it's because I'm paid to do it. When I do it, I do it using a checklist, a procedure, and a plan. I do it knowing that I am not harming the engine, or endangering the flight, the aircraft, others in the aircraft or those on the ground. I do it because it's safe, it's sometimes necessary, it's appropriate, and it's approved by the engine manufacturer.
Shutting down the PT6A in flight is approved by the engine manufacturer, incidentally. Just as it is by the airframe manufacturer. And the propeller manufacturer (that's why it's a full feathering propeller, you see).
As far as why a tprop feathers...are you so stupid as to think that the anti torque system on the Conquest is there, because you happen to think that when the engine shuts off of a freewheeling turbine....that the prop goes right into feather..?
The "
antitorque," you say. Okay.
You may be thinking of the Garrett motor, which does incorporate a negative torque sensing system (NTS). NTS moves the propeller blade angle toward high pitch to load the propeller from the engine, when negative torque is sensed; it helps keep the engine driving the propeller, instead of the other way around.
This isn't necessary on the PT6A; it's a free turbine, after all, and the propeller can't drive the gas generator. The propeller is controlled instead by the governor, which works the blade angle as required to maintain a constant RPM when in the governing range.
On the Conquest, as with all turboprops, the concept of torque is a good thing; we want torque.
Now, you ask if I'm stupid enough to believe that the propeller feathers when the engine shuts down. No, I'm not stupid, and yes, the propeller feathers when the engine shuts down; that's part of the shutdown and feathering procedure for all PT6A installations, including on the Conquest. You ensure it feathers by feathering the propeller, you see. You didn't do that, in the scenario you describe. In fact, you didn't try.
For all your rambling about the propeller governor "
making metal" and being unable to be feathered, you never tried to feather the propeller or shut it down (perhaps because of your gross misunderstanding of the construction, operating principles, and function of the equipment you *
claim* to have flown).
I find it incredibly ironic that you'd hold out your hand on this site (not once, but twice, of late), begging for a job, yet turn around and openly profess such unprofessionalism, poor judgment, and lack of understanding and training.
You may be thinking of autofeather features, and you may be thinking of the actions of the propeller governor when the propeller attempts to overspeed; the actions are similar; propellerblade angle is increased to load the propeller, reduce RPM. The rationale is slightly different as is the process, but the result is a higher blade angle (moving toward feather).
Lose oil pressure, of course, as in shutting down the engine, and the propeller will feather.
And did you think that the reason for the anti torque system being there had a little more to do with just the pilot reaching over and feathering the prop, but maybe, you know...just maybe...Pratt and Whitney....you know the engine guys...had little faith in the ability of the pilot to feather a failed engine in time before that big ol three bladed McCauley or 4 blade Hartzell created so much drag that Vmc would be reached in in no time, and just to keep the plane flying, you needed to go down, to the tune of 3000 FPM...holding enough power on the good side, but enough speed forward to counteract so much asymetrical yaw and roll that the plane was almost un--flyable..
Autofeathering systems are not new, and no, the airplane will not fall out of the sky at 3,000 fpm because the propeller didn't feather, nor will it "flip" on you if you keep flying the airplane. Especially from 24,000'.
This is really irrelevant, however, as you never had a propeller that failed to feather. You had a pilot (allegedly YOU) that failed to feather the propeller. There was no 3,000 fpm descent. Instead there was a 10,000 fpm descent that you initiated, according to your own text. You failed to follow procedure, failed to secure the engine, failed to feather the propeller, and still managed to make a mountain out of a molehill with triple the rate of descent you assumed might take place if the problem you assumed existed (which it did not). Go figure.
In most cases where autofeather systems are provided, one shouldn't count on them, and even where one should let the autofeather system act first, procedures are established to follow up by manually feathering the propeller. All of which is far afield from the subject of loss of oil pressure or quantity. Never the less, you failed to use procedures that were available to you, guessed at the problem, imagined causes that weren't there (as well as the effects), and then acted entirely inappropriately for all of the above (even if the problem had existed as you dreamed it up to be).
Another problem here is that reading your previous posts, you're a missionary of single-pilot operations. You don't belong in a crew cockpit, let alone a single pilot cockpit. You don't appear to be able to correctly decide your way out of a wet paper bag, let alone be trusted with flying an airplane (be it a "million dollar" airplane or a paper one).
Autofeathering systems aren't P&W items, incidentally, but customer served accessories, generally installed as an issue of certification.
The pilot must always be capable of feathering the propeller.
There are some installations of autofeather systems in which the pilot shouldn't "verify" with the power lever before feathering, because such action defeats the autofeather function. The pilot should still manually feather the propeller, however; something which you failed to do.
Thanks Guppy...for setting all of us straight....
Actually, most here were quite straight to begin with. It's you that's a little crooked.