wing spar repair?

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4280
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wing spar repair?

Post by 4280 »

I recently bought a 1946 Cessna 140 which had been propped and got away and ran into a fence row. Damage is pretty much limited to the left wing tip and right elevator, It may be one of the lowest time 140's in the country...630 TT !! And, yes that is true. In fact the mate to it is here close by with 650 hrs. They were bought at the factory and flown to Knoxville, TN on the 16th of November 1946. But, I digress. The damage to the left wing is between the landing light and the wing tip bow. Both are intact ! However, the front strut is bent backward about the last 12" at maybe a 20-30 degree bend. Is there a repair possible or does the front spar or wing have to be replaced ? Thanks you for any help. Oh, who is the guru who can answer that question for me ?
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Re: wing spar repair?

Post by 6643 »

You can use AC43-13.1b as a structural repair manual.

When you say "the front strut is bent backward about the last 12" at maybe a 20-30 degree bend," do you mean the lift strut? That's going to be tough to repair without a jig, but there are repair methods for streamline tubing in the same AC. You can get a new one from Univair, but the rear strut won't match the other side. However, they have the jig, so, may be able to fix yours.
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Re: wing spar repair?

Post by 4280 »

I'm sorry...I miss-spoke when I switched from spar to strut.It is the front SPAR !
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Re: wing spar repair?

Post by 6643 »

Is that the only thing that is bent? Any pictures?
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Re: wing spar repair?

Post by V529 »

Depends on what your sheet metal expertise is. I had a somewhat similar situation, I replaced the wing.

Is the wing metalized or fabric?
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Re: wing spar repair?

Post by 4280 »

It's fabric wing. Everything from The Landing light to the wing tip bow is pretty much destroyed the rear spar is not damaged and the front spar has that been. I may be able to post a picture
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Re: wing spar repair?

Post by 6643 »

Moving this to the Tech Discussion forum.
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Re: wing spar repair?

Post by 4280 »

The bend on the front Spar is midway between the last two lightning holes in The Spar. It is bent at station 72.125
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Re: wing spar repair?

Post by 4280 »

I have the aircraft inspection, repair and alteration manual with a c 43.13 - 1B and 2B but so far I haven't found much help as far as splicing or reinforcing and aluminum spar
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Re: wing spar repair?

Post by 6643 »

Repairing the spar is a major repair. If the exact repair isn't covered in 43.13 (look in Par 4-58) then you either need data from Cessna or you need to replace the spar.
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