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Old 28th August 2024 | 13:39
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Vessbot
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Originally Posted by TheBusFlyer
Having thrust controlling rate of climb and elevator controlling speed…won’t both interfere with each other ?
Not having flown the 777 I was gonna sit this one out, but seeing that people aren't understanding your question (boiled down to this sentence) I'm gonna go ahead and speculate. (A FCOM I have a copy of, is no help either). Probably one of 2 tings is happening:

- It's not responding to rate of climb with thrust actively in a closed loop, like every other autopilot mode responding to its parameter, but rather the required thrust is calculated from altitude, weight, and temperature, and set at the result of the calculation. So it's just a fixed value of thrust like THR REF or CLB or whatever, but less.

or

- It's responding to rate of climb with thrust but extremely slowly. So, on the time scale of an elevator response to speed, the thrust is essentially fixed. The two frequencies are so different from each other that they don't interfere.

I suspect it's the first.

Last edited by Vessbot; 2nd September 2024 at 04:58.
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