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Guest Adverse Yawn

When to transition from A/T to manual throttles on Big Iron ?

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I have been wondering at what altitude I should optimally transition from using the AT on an AP-coupled approach to using manual throttle adjustment on large jets like the 747-400 and 767 prior to touchdown. I am particularly keen to get this right when approaching in heavy gusting winds. I have tried turning the AP off at 500' AGL and having AT on all the way down to about 100' AGL; and also tried switching AT off at 1000' to 1500' AGL and turning off the AP between those altitudes and down to 500 AGL. I do not know however whether my procedures are realistic.Any advice appreciated, thanks.JS

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you might want to have them go all the way to about touchdown or 10-20 feet above, and disengage them to hit the reverserspersonally i try to use manual throttles all the way in, its so much fun and gets to me to really learn how the airplanes react

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In the real world most pilots get rid of the auto throttles once they turn off the autopilot. Autothrottles are great and they work very well when the autopilot and the aircraft are doing the work. Newer systems work much better than some of the older systems where computer memory and air data computers are less capable. In our MD-88's in gusty conditions the autothrottles tend to chase the airspeed so we turn them off and can get a better more even response doing it manually. I think most autothrottle systems I have seen tend to chase airpeed when it gets turbulent or very gusty and when you are manual you tend to be able to smooth out the changes where the autothrottles seem to make too large of a correction these condtions. I usually turn them off on our MD-88's when I take over manually on final approcah prior to dropping the landing gear as I want to control the power as I see fit with config changes and pitch changes. I can do a smoother and faster job than the autothrottles can. When we are doing a coupled approach to CAT 3 conditions the autothrottles are required. They need to be off on any other approach prior to touchdown and that is a limitation. Otherwise thier os no real "rule" if you will about thier use. Whatever level of automation you choose to use is up to you. As a side note, during low vis approaches such as CAT 2/3 there is rarely much wind or crosswind and we have fairly strict limits for these due to autothrottle use during these conditions.Hornit

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Most carriers (esp with Airbus) are mandating that autothrottle stays on for the entire flight unless there is a reasonable chance that safety is compromised.

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Delta doesn't mandate that at all. We are required to be proficient without all the aids and although its not done normally, I can run with autothrottles off all day If I like. Its a pain though, I'd ratehr have 'em! :)Hornit

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Perhaps I should reword to most carriers that I know of in the UK :) e.g. BA and Easy. OK, so that's only two :+

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