Prevost XLII Skin Delamination Repair

[davidbrady]

Hi Hish,

I thought about Lisa (FEA) but I don't know enough about the XLII panel geometry to model it. It'd have to be a solid model, simply supported and elastically restrained to model the adhesive. As usual, getting the constraints right is the hardest part and it may be beyond the capabilities of Lisa, for instance I'd have to use a spring to model the glue and that may be too much of a simplification. The idea is that the side panel, when compressed longitudinally parallel to the ribs, needs to be able to pinch in or out at the top or the bottom to allow buckling. Pretty complex for Lisa. Prevost can easily adjust the buckling strength by a factor of 10 over a flat piece of steel by adjusting the rib count and the dimensions of the ribs. A flat piece of steel has very little buckling resistance. This is what we see on the sides of Wanderlodge PT's, Wide Bodies, and LXi's. You can sight down the side and see the skin buckle on a hot day. The same with the XL, the skin can get very wavy. Folks like the flat looking non-wavy sides of the XLII. The rivet fix Prevost is now using on the XLII only uses fasteners on the four sides, nothing in the center; maybe they know something they're not telling?

Remember this thread: http://www.prevostgurus.com/showthread.php?tid=71. Gives us a good look at the rib count and dimensions.