When I got out of the plane the other day the Step gave way! That was exciting. The failure was along the intersection of the weld and the bent steel piece and ran from the bottom of the assembly at the crest of the bend up around the top of the step and into the large hole in on the bottom of the gear leg. I suppose that is right where all the tension is when someone steps on the step.
I find surprisingly little on the forum, webpage, and internet in general on this. No good source that I can find for replacements except junkyards which I find a little surprising
I saw a 140 getting annualed today in Liberal, KS and both of its steps are starting to crack along the top of the welds. We must not be the only ones!
Any suggestions from the brain trust?
Steps
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tonycondon
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- Name: Tony
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Steps
N2395N
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8475
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Re: Steps
Hi Tony, was just looking at my steps today and thought the weld might be a high stress area. Your anecdote confirms this. Can you post a pic? Thank you.
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8342
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a64pilot
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Re: Steps
The step hole in spring gear worries me, See I believe eventually all spring steel will eventually fail, and that hole could be where a crack starts.
Years ago when I painted my aircraft I polished that hole and checked it for cracks just visually, which isn’t a good check for high strength steel I know, but I believe polishing it will help remove any stress risers, and when I put the bolt back in I covered it in Black Bear to help prevent rust.
Crack growth propagation in high strength steel is pretty rapid, so unless your Magnafluxing or Eddy current inspecting every annual, you may not catch it before failure.
Years ago when I painted my aircraft I polished that hole and checked it for cracks just visually, which isn’t a good check for high strength steel I know, but I believe polishing it will help remove any stress risers, and when I put the bolt back in I covered it in Black Bear to help prevent rust.
Crack growth propagation in high strength steel is pretty rapid, so unless your Magnafluxing or Eddy current inspecting every annual, you may not catch it before failure.