Figured I'd jump in on this rebuilding thread since my question is exactly about... just that.
Extensive foam damage to the "tub" of the varieze.
- No delams
- Core Crush damage
- "face sheet debonding"
If you are unfamiliar with these terms or with mechanics of what ACTUALLY happens under the skin when a nose wheel up landing occurs or when u impact it on the side w/ a baseball reference this "short review":
http://www.tc.faa.gov/its/worldpac/techrpt/ar99-49.pdf
Rest of A/C checks out and needs a complete OH of all the rubber/hoses connections ect. No biggy, and yes the panel can wait!
I've been giving these recommendations:
- Buying built tub
- Building new tub
- "your fine" (ya... no)
- And mine
My solution is to completely de-skin the tub. This will leave only the inner skin. According to failure theory and testing the inner skin is usually undamaged. With the foam removed any buckling of the inner skin should be visible and repairable at that time. So what’s my question?
The foam call for was polyurethane foam (great characteristics for shaping, not so much for impact resistance)
Questions
- What foam should I use? (Opinion should be backed by facts plz)
- Anyone have any online references I should study?
- Any pitfalls I didn't think about?
- Any extra caution I should use? (Besides do it right the first time)
Thanks for your help,
Derek Roper
MS&T Aero/Mech Engineering
Varieze
