In measuring the curvature of the loop, we found several cords where the curvature exceeded the maximum design curvature for a K36. The fact that K36's have successfully used the loop is a function of conservative specs and/or lots of slop in the running gear. However, with the shop doing lots of work on running gear that also removes some of that slop, Ed does not want to take the risk of cracking a frame, a difficult fix. The problems with the loop are a function of poor construction and/or slippage of the fill since then. Dave Roger's trip in '97 is the best photo feight charter I have ever been on.