High speed trim with flaps down, 737
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High speed trim with flaps down, 737
When you lower the flaps on the 737 the trim motor gives you a higher trim speed. If this is not working correctly, ie slow trim with the flaps down, is this a go or a no go item? I could not find any reference to this problem in the MEL, also the engineer looked puzzled.
Last edited by raspberry; 20th Apr 2007 at 19:01.
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... the trim motor gives you a higher trim speed
I'm really quite confused .. what does the trim motor have to do with trim speed ? and why would you want a higher trim speed with greater flap deflection ?
I'm really quite confused .. what does the trim motor have to do with trim speed ? and why would you want a higher trim speed with greater flap deflection ?
). Faster with flap extended.
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Not only is it, as ASFKAP mentioned, legally a "No Go" item if it isn't in the MEL, but from an engineering and safety perspective it should be a "No Go" also: you have something wrong with your stab system (whether the motor or the control unit) and that's hardly a trivial system.
The higher trim motor rate when flaps are down/in motion is presumably because it's required, so you may not have the requisite amount of handling. If your aircraft has a flap/stab interconnect, chances are the trim command in response to flap motion is for a number of seconds, not for an actual stab change, so if the rate is wrong, you'll get the wrong amount of stab as a result.
You also don't know if anything else is kaput in the stab system. Inflight would be a bad time to find out.
The higher trim motor rate when flaps are down/in motion is presumably because it's required, so you may not have the requisite amount of handling. If your aircraft has a flap/stab interconnect, chances are the trim command in response to flap motion is for a number of seconds, not for an actual stab change, so if the rate is wrong, you'll get the wrong amount of stab as a result.
You also don't know if anything else is kaput in the stab system. Inflight would be a bad time to find out.
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is this a go or a no go item? I could not find any reference to this problem in the MEL, also the engineer looked puzzled.
how did you find out that the high speed trim was not working ? Usually you set the T/O trim unit in the preflight procedure and you have flaps up. Did you recognize the problem in the after landing scan while reseting the trim with flaps not up ?
