Cobra Trailer Spare Tire mount failure

Six years later, in my 1992 Cobra the vertical post that holds the fuselage nose cone and the spare tire broke at the base, allowing the whole assembly to topple backwards when the fuselage was removed. Apart from cracking the thin wall of the storage bin, no consequential damage.

The post is retained by two vertical, upward-facing bolts at the base, their heads welded onto the "U" bracket that secures the aft end of the trailer tongue. One of the bolts broke off leaving the head still attached. The other weld failed, allowing the bolt to break loose.

It's just one more thing to inspect periodically. If your trailer is similar (every Cobra/Komet seems to be slightly more evolved), pull the fuselage out and climb up into the trailer. Then go forward with a flashlight and check the bottom of the post to ensure both bolts are solid. Rock the nose cone/spare tire to make sure. If you reach in from the front door and try to yank on the tire or nose cone when the fuselage is in the trailer, the fuselage will prevent movement from side to side or backward and a single bolt will prevent it from rocking forward even if the other bolt is broken.

One nice change: this stuff usually happens at a contest.

BTW, I didn't want to deal with removing the wings/fuselage, then towing it over to have someone weld it all up again (and tell me it's a bad design--which it is, notwithstanding the 20+ years it sufficed). So I drilled through the bracket and tongue where the upward-facing bolts had been welded and replaced them with downward facing Grade 8 bolts secured with washers/nuts inside the tongue. A little awkward to reach in there but it will do for a while. I plan to reinforce the post and possibly move the spare tire to another location per the discussion in the 2009 thread.

Chip Bearden
ASW 24 "JB"
U.S.A.