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Horizontal stabiliser without a trim tab?

If the elevator link breaks, you will presumably die.

Unlikely. I have to imagime most aircraft that use some kind of spring bias or bungee instead of a trim tab (or variable incidence tailplane) with no resistance in the circuit (iow with the elevator simply free) will trim out to some kind of sane flying speed within the normal operating envelope. With that being the case you then adjust engine power so you’re flying at that speed if you want to fly level, reduce power to descend, or increase power to ascend. Even if that speed is quite high all you need do is find a sufficiently long runway and certainly in Western Europe this shouldn’t be an issue.

Andreas IOM

Trim tab drag has been given as the main reason for alternative trim arrangements, however is it not the down force on the tailplane that creates the drag? This why flying at the aft CofG limit gets the best speed. If there was very little downforce required then presumably you get minimum drag, whatever the trim system used. If a trim tab is in perfect trail I’d guess it creates no drag.

I think the horizontal tail’s lift/drag ratio is likely better without a deflected trim tab.

Trim tab drag has been given as the main reason for alternative trim arrangements, however is it not the down force on the tailplane that creates the drag? This why flying at the aft CofG limit gets the best speed. If there was very little downforce required then presumably you get minimum drag, whatever the trim system used. If a trim tab is in perfect trail I’d guess it creates no drag.

I made the statement regarding Mooneys…slightly tongue-in-cheek….I guess only other Mooniacs would understand!

YPJT, United Arab Emirates

The Aquila A210/211 also has a spring system. Works quite well. Light stick forces anyway.

FI, ATPL TKI and aviation writer
ENKJ, ENRK, Norway

The Aerospool Dynamic WT9 also uses a sprint system, works very well.

EBMO, EBKT
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