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A300Capt, I know you flew the 757/767. When did you use Climb 1/2 modes? Was there a specific SOP regarding using the less-powered climb modes?
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Anytime you selected a reduced t/o power setting (derate 1 or 2) the default for climb power would be climb 1 or 2 (ex: derate 1 t/o would automatically revert to climb 1 etc). We could also do an "assume" (or "flex" for the Airbus fans) temp reduction off the derate setting. Confused?
Yea, it takes some getting use to but becomes clear after some use. The use of reduced t/o and climb power settings is SOP except during inclement wx conditions or MEL considerations.
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(Aside: It was very tricky trying to hand fly with autothrottled in the 737-300 sim! Every altitude bust was exaggerated since the autothrottles would add or remove power as you climbed or descended, respectively.)
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Funny thing you mentioned that. 727 guys/gal have a heck of a time initially when flying the B75/76 or even the 737. Reason being, the 727's thrust is inline with it's CG. You feel a push when power is applied but there's relatively little pitch change associated with it. Same with power reduction.
With the wing mounted engines on the B75/76/73 etc, the thrust line is below the CG. We know that everything pivots around the CG. When power is applied and with the thrustline being below the CG, the nose has a tendency to pitch up relative to the amount of thrust being applied. The opposite is true when power is reduced.
With me so far? Good.
Now, introduce autothrottles into the mix. Let's say you're hand flying an ILS with the autothrottles engaged to "speed" mode. If you raise the nose on any airplane with a constant power setting the airspeed will gradually bleed off. If you let go of the yoke the nose will drop to try and regain the speed it was trimmed for (nothing new..basic stuff here). Now, with autothrottles, the problem is that when you raise the nose slightly the speed bleeds off and the autothrottles compensate with more power. The more power now increases the nose pitch attitude..reducing speed again and...increasing more power by the autothrottles etc, etc, etc. Can you see the cycle? The reverse is true if you push the nose over. Speed increases so the autothrottles reduce power which in turn pitches the nose over more...increasing speed....more power reduction etc. It's a dog chasing it's tail scenario. The new crewmember is chasing the autothrottles while the autothrottles are chasing the pilot.
It's recommended that if you're hand flying to turn the autothrottles off. Experienced crewmembers, familiar with the idiosyncrasy of the autothrottle system still prefer to hand fly with them engaged.
I was a B75/76 sim instructor for many years and most people new to glass cockpits and autothrottles fought with them while hand flying an approach initially. I made it a point to explain the whole potential negative stability autothrottle thing to them prior to the first sim period and most appreciated that advice.