2engsout
Posts: 108
Joined: 2/8/2003
From: omaha, NE,
Status: offline
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OK, I understand and I like it so far! Lets say your flying along at full throttle like I do, and one engine begins to overheat and the rpms sag thier way down to 2000 RPMS before it stops turning. That could take 3-5 seconds. I've seen it happen. By the time that sagging engine drops below 4000 RPMS, that spinning propeller disc is producing 5 times as much drag as a completly dead engine. Thus, you are well into TROUBLE !!. Remember, at 65 mph at full throttle on 2 engines, at 7000 RPMS, everything is fine. One begins to sag. The plane immediatly begins to slow down = FACT. When the sagging engine is down to 6000 RPMS, the plane is just beginning to yaw=FACT. By the time its at 5000 RPMS it IS yawing and slowing even more=FACT. If I can't here my engines comming out of sync, at what point dose this rapidly growing crash inducing yaw tell me to throttle back the good engine??? I like Mustang51 idea that the good engine should follow the bad engine down= NO YAWING to scrub off all my airspeed!! BUT, lets just say, for discussion purposes, that when the failed engine drops down from 7000RPMS to 6000 RPMS, the good engine begins its RPM reduction program and follows the bad engine in sync all the way down to 3ooo RPMS. At that point, the pilot would have to bottom his throttle stick, and then he could regain control of the good engine, with a preset maximum rpm of say, 5000 RPMS? Even at full stick he is only going to get 5000 RPMS out of the good engine. That 5000 RPM max will keep the plane from snapping when the pilot begins his recovery. Even if he is in a panic, he has only got enough available thrust to stretch the glide. And that is ALL he should be trying to achive, since very few twins will even maintain altitude on one engine. I have seen where a pilot was attempting to maintain altitude to make it back to the runway at full throttle with only one engine. He was pretty low when his engine quit and since there was NO rate of decent, the plane continued to slow down until its airspeed would not support the indended control surface input. Thus stalling all surfaces and snapping into mother Earth! Had the remaining eng been limited to 5000 RPMS, a very nice CONTROLLED rate of decent would have occured!! Yes, it would have been short of the runway, but still in ONE PIECE!! This type of setup sounds good to me and the preset RPM max would be adjustable to suite the individuale planes requirments by the pilot.
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RE: Eletronic engine syncronizer - no joke - 
