Electric T&B off?

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6597
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Electric T&B off?

Post by 6597 »

So I have this ancient T&B in my panel. When I spool it up on the ground the needle is centered, with plane leveled with a bubble level across the lower door frames, ball is centered.

When I fly and my Artificial Horizon confirms level flight I most often get a slight needle to the left, bubble still centered.

Is there some trim detail I am missing or does the needle just like messing with me to give me another little futzy thing to fix?
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Re: Electric T&B off?

Post by 6643 »

6597 wrote: Tue Jul 04, 2023 1:43 pmmy Artificial Horizon confirms level flight
What does the compass or DG say?
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Re: Electric T&B off?

Post by 6597 »

Will check on next flight. What should I look for? I am blessed with a very good vacuum DG, spot on the runway heading after an hour of flight, who'd a thunk....

Wet compass on the other hand...

I've confirmed this needle thing in calm no-wind conditions.
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Re: Electric T&B off?

Post by 6643 »

The TC is saying you are in a (roughly) 8 minute coordinated turn, so, 45 degrees in one minute. It might go unnoticed.

If you have an artificial horizon that says wings level, and you are turning, the turn is not coordinated (and the ball wouldn't be centered). If you're not turning, the needle is out.

First thing I'd check is the instruments are level with (parallel with) the front spar. The spar and gear box should both be level.
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Re: Electric T&B off?

Post by 6597 »

To revive an old thread, found the problem.....now have the proper T&B in and all is well. Just when I thought there weren't any other things 'off' in my bird. Weather is lousy here so am playing behind the panel. Hats off to Century Instrument Corp. in Wichita.
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Re: Electric T&B off?

Post by 8362 »

Nice, surprised it worked at all.
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Re: Electric T&B off?

Post by 6898 »

That's a good one,thinking the person who installed that would have put a 28 volt battery on the pass seat to run it? LOL
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Re: Electric T&B off?

Post by 6643 »

A 12 volt battery wired in series with the system battery. And a switch to charge it when you don't need the T&B. :roll:
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Re: Electric T&B off?

Post by 6597 »

Truth of the matter is now that engine overhaul is done I'm starting to look for the little nit-picky things on the bird. I've flown this thing for ages and just never got around to dealing with the T&B. I stuck my cellphone camera up in back of the panel to see what was going on and lo and behold....
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