Safetying RH Balance Turnbuckle

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6643
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Name: John C
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Aircraft Type: 1946 C140/C90
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Re: Safetying RH Balance Turnbuckle

Post by 6643 »

Can't tell you why, but, SLN-65 states that the wire goes around the bolt, not the eye, and to check it for wear at inspection time.
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6597
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Re: Safetying RH Balance Turnbuckle

Post by 6597 »

I'd sure like to see a pic of that, is that supposed to be a fork or a pin eye for the carry-thru cable on the right side? I think the parts books shows for an eye instead of a fork. Fork would be much easier and make sense with the SLN-65.
SLN-65 excerpt- 2. Inspect the safety wire on the aileron carry-thru cable turnbuckle in the right wing for wear and breakage at that point where the wire passes around the bolt that secures the turnbuckle eye to the bellcrank. Excessive wear of the safety wire is possible at this point as a result of a combination of clearance and bellcrank action.
cdoughty
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Re: Safetying RH Balance Turnbuckle

Post by cdoughty »

Fork is too wide to fit between the ears of the bellcrank.
My airplane initially had the safety wire just wrapped around the pineye shank-in other words it wasn’t really safetied.
When the sln says around the bolt they mean the bolt through the eye and in a big loop following the eye outside surface. If this loop gets caught between the eye and the bellcrank ears it could pinch and wear or break.
I replaced it with a clip style turnbuckle.
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6597
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Re: Safetying RH Balance Turnbuckle

Post by 6597 »

I replaced it with a clip style turnbuckle.
I'd like to present that to my IA for my next annual if you have a part number for that. I really want to change that out.
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