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horace

ENG FAIL / Inflight Start and Autothrottle

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Hi,yesterday I had my first randomized engine failure. With the help of the abnormal procedures I managed it quiet well I think but though I have a question concerning the inflight start procedure and autothrottle.I can't find anything in the abnormal procedures which tells me to deactivate autothrottle after an engine failure so I left A/T active. Well here's the first problem: According to the abnormal procedures the thrust lever of the respective engine has to be idled - but how? With A/T? I selected Engine 1 with (E + 1) and pressed F1 for idle. But as soon I did that the lever automatically moved back by the autothrottle. Therefore I also had a problem with restarting the engine because the thrust lever should stay in idle position for about two minutes to let the engine stabilize. I don't know how this in real life is. Can you uncouple one specific thrust lever from the rest so the autothrottle controlled servo won't move it? Or is that kind of FS9 limitation or am I simply doing something wrong?AFAIK in the 737 you HAVE to disconnect A/T when an engine failure occurs.Thanks for your help.


Hendrik Horeis

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This problem is created because your joystick isn't motorized and doesn't have four individual levers. MSFS is simply working around this problem.It's a little difficult to describe, but in the real world, all four 744 thrust levers are driven by a single autothrottle motor through a resistive device known as a clutchpack. You can move the throttles independently (i.e. you can stagger them) with your fingers (overcoming the resistive force of the clutchpack), but if the autothrottle is engaged, the A/T system will see you have gained or lost airspeed and it will activate the (single) autothrottle motor... and all throttles will move in unison (in their staggered positions).The levers will synchronize however, when they hit the idle mechanical stop (if the A/T commands them to idle for, say, descent). If thrust is required after that, all the levers will move forward in a straight line (and you will have to physically restrain the troublesome engine thrust lever if you still need it at idle). In a way, MSFS is probably trying to reproduce this synchronization.. but it's mistakenly doing it at all thrust lever positions.Why only one A/T motor for 4 engines??? The 777 has two A/T motors.. one for each engine.... and therefore has two A/T switches. The 744 has 4 engines and the 744 designers probably thought that things would get too complicated and the MCP panel would get too cluttered if there were 4 A/T switches(?).Hope this helps more than it hurts.Cheers.Q>

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Nice to hear from a technician, very interesting! :)I also didn't expect the 744 to have only one A/T motor, that surprises me. However, for a workaround I'll simply switch the A/T off if I need one at idle (e.g. an inflight start) - that's not a too big problem at all.Thanks, it helps and hurts in the same way :(


Hendrik Horeis

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