Elevator trim tab play

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PedroDTeixeira
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Elevator trim tab play

Post by PedroDTeixeira »

Hi Guys,

During the last annual to our XL2 We found the Elevator trim tab with play. We consulted the manual and it seems it cannot have any.

We have checked and it seems to be coming from the bushing rail that makes the movement of the trim...

As Discovery Aviation is not answering anybody, I would like to know if you guys already experienced this issue and how did you solved it...

Thank you very much for your help.

Best Regards,
Pedro Teixeira

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XL2driver
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Re: Elevator trim tab play

Post by XL2driver »

Does the maintenance manual not specify the remedy?
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Maintain VSO+1

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paulmilo
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Re: Elevator trim tab play

Post by paulmilo »

No issue with the trim tab, although I did find free play in the elevator that was caused by the incorrect placement of washers at the bell crank located at the rear of the belly cowl area where the torque tubes enter the fuselage.

The washer placement meant that the bolt shank did not push through the rod end / heim joint, so the thread area (which is narrower) was sitting at the rod end (instead of the shank). That provided a teeny bit of play that was amplified by the torque tube configuration and could be felt on very smooth days as slop in the controls.

Once I moved the washers to match the drawings, all G - no free play whatsoever. You might want to check what is causing the freeplay - if it is a rod end it could be something as simple as what I found.

Good luck.
———————
Milo VH-KXY
Australia

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paulmilo
Posts: 155
Joined: Sun Jun 03, 2018 11:03 am
Based: YMNG
Tail Number: KXY
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Re: Elevator trim tab play

Post by paulmilo »

No issue with the trim tab, although I did find free play in the elevator that was caused by the incorrect placement of washers at the bell crank located at the rear of the belly cowl area where the torque tubes enter the fuselage.

The washer placement meant that the bolt shank did not push through the rod end / heim joint, so the thread area (which is narrower) was sitting at the rod end (instead of the shank). That provided a teeny bit of play that was amplified by the torque tube configuration and could be felt on very smooth days as slop in the controls.

Once I moved the washers to match the drawings, all G - no free play whatsoever. You might want to check what is causing the freeplay - if it is a rod end it could be something as simple as what I found.

(note that I initially assumed it was the bush that the bolt/rod end sat inside and was looking at complex solutions to change diameters etc before I realised the issue was not the bush, it was the bolt/rod end. Look for the simple solution first :-) )

Good luck.
———————
Milo VH-KXY
Australia

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