Fuel sump safety wire

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dcannon
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Fuel sump safety wire

Post by dcannon »

Would any members please share a photo of their safety wiring for wing fuel sumps? The anchoring hole is punched far enough away to confuse me about how to wire this with some tension but also without damaging the aluminum. 0.020 metalized wings in my case. Seems fabric makes this even more tricky?

F-5N from today for your enjoyment.
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6643
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Re: Fuel sump safety wire

Post by 6643 »

You don't really need any tension. An IA I once worked with told me safety wire is there to keep the fastener/part from falling off. If it unscrews 1/6 of a turn it won't cause a catastrophic failure.

If the tank has a tapered thread for the valve then it originally didn't come with any safety wire.
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dcannon
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Re: Fuel sump safety wire

Post by dcannon »

Thank you John, as always

Never wired from when I bought this airplane. Makes me wonder if they are tapered thread. Im certainly not going to pull them out just to check.
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6643
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Re: Fuel sump safety wire

Post by 6643 »

Look at it from the side, between the wrench flats and the tank. If you see threads, it's tapered thread. If you see a gasket or o-ring or there's no gap, it's not. I recall the tapered thread valves are not drilled for safety wire, so, if it's drilled it probably should (read "must") be safetied.
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dcannon
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Re: Fuel sump safety wire

Post by dcannon »

No gap - mystery solved. Safety wire it is!

Thank you John
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Re: Fuel sump safety wire

Post by edidin »

FWIW mine is wired to an area washer with a peripheral hole under one of the wing root fairing screws.
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