Used on Solid Rocket Booster hold-down posts
Space Shuttle Columbia Launch-Exploded Frangible Nut. Before a Space Shuttle launch, frangible nuts were placed at the top of the four 28" long x 3.5" diameter bolts that secured each SRB to the Mobile Launch Platform. At the instant of launch, two embedded NSD (NASA standard detonator) explosive charges broke each nut into two halves allowing the release of the craft from the MLP. The nut halves were caught in a blast container and occasionally awarded to astronauts or, as in this case, Shuttle-related VIPs such as Charles D. "Chuck" Clary. We offer both halves of this one, verbally attributed to STS-107, the ill-fated last mission of the Columbia. On the top of one section, the following information is printed: FRANGIBLE NUT 55340/10306-0001-802 MFG. DATE: MO: 01 YR:86 MFG: 19113/114850-11 LOT SER. NO.: AAF-1000589