Les - As I suggested in my previous posting, a survey of the 'fleet' would be a grand idea. All we need is some guidance on how to accomplish it. As far as your figures are concerned, if the percentage of "imperfect" bolts (whatever that means) is as high as 50%, we have a great deal of "worrying" to do. Keep in mind my perspective ... on one car (mine) I had one break completely, and the other was significantly bent. And, when we looked at another small group of cars, over 1/3 of the bolts were bent. As I mentioned in my first post on this subject, I am an engineer on the Boeing 747 program. Do you remember the crash of a 747 freighter in Amsterdam in the early 90's? It was only the second crash of a 747 that was attributed to failure of the fuse pins that attach the engine pylons to the wing. The fuse pins are fancy bolts that hold together critical joints ... that had no reliable structural redundancy. With only two catastrophic failures in a fleet of almost 1000 airplanes, the Boeing Company undertook a program to redesign the fuse pins and pylon attachments, and this program ultimately cost the company over $1 Billion. I was the Principal Lead Engineer given the responsibility of the new fuse pin design, and my own concept layouts for a redesigned pylon attachment were used as the basis for the new design that was ultimately implemented. My point is that well over $1 Billion was spent over a short period of years because of two failures that were attributed to cracking and corrosion of the fuse pins, in a joint that was not originally designed with the level of fail-safety and structural redundancy that is currently state-of-the- art. In addition to the people on the List who said that they had experienced failures of the TAB, I know of at least one PNDC member who also had the misfortune of a total fracture. Luckily, it happened at low speed going over a bump. My fractured bolt happened during routine inspection, and the lab later confirmed that it was 90% cracked through when I tried to check the torque on it. It would have failed on the trip home from the tech session if I had not discovered it when I did. Am I worried about this entire situation? Damn right! If you aren't, then I will pray for you. Toby Peterson VIN 2248 Winged1 --- In dmcnews@xxxx, Les Huckins <jhuckins@xxxx> wrote: <snip> Secondly, actual bolt failure is a very tiny percentage (less than 5%), of course if yours should be one that fails you immediately go to 100%. Final figure is that a very high percentage of bolts are not perfect should you inspect them, best guestimate I can get is 30% to 50%. <snip>