View Full Version : Critical Engine
Can somebody please explain to me what
a Critical engine is please,
--NOT NOW--
Code Blue
14th Feb 2001, 05:27
Critical Engine:
That engine in a twin, which when failed, causes the most control difficulties.
It depends on which way the props rotate. For various aerodynamic reasons if the props both rotate clockwise when viewed from the cockpit - as in US manufactured a/c - failing the left engine will produce much greater control problems than the right. For Props rotating counterclockwise - older UK/European a/c - the right engine is Critical.
Some training twins, eg the Seminole have counter rotating props and thus no Critical Engine.
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Check-in
14th Feb 2001, 05:36
And for a jet, which suffers no measurable torque effects, the critical engine, on the ground during takeoff, in any crosswind, will be the one on the windward side. If a four engine jet, of course the outboard one on the windward side. 10 knots of crosswind could add 5 knots to VMCG, so not to be ignored if you do asymmetric training in the airplane.
Many thanks for your help
--NOT NOW--
Pete Otube
14th Feb 2001, 18:35
KATO- ignore all the above replies.
The critical engine is the last one......
>>so not to be ignored if you do asymmetric training in the airplane.<<
....or 3 engine ferry flights. "Good engine, good wind."
4dogs
19th Feb 2001, 18:08
Check-in,
I guess that's the upwind side for non-sailors?
Quid (or any B747/A340 drivers),
Have you seen any data on the wind effect on Vmcg, particularly for 3 engine ferries where the inoperative engine is the inboard upwind engine?
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Stay Alive,
[email protected]
4dogs-
No data that I've seen. I can tell you from doing the training (and actual experience) that it would equate to about 5-8 knots of crosswind.
An outboard will be the equivilant of about 15 kts. 15 knots from the "good" side vs. 15 knots from the "bad" side will make about 2500' +/- difference in my liftoff point.