The FOS Derelict Past emits the Federation universal danger and group signal on a local DF channel. The Derelict Past's captain, Tom Derdest, counts every acronym he uses on a daily basis. FOS, federal official ship, FO, federal official, DF, duo-flux, SDF,  stealth duo-flux, LRDF, long-range duo-flux, TF, tri-flux, FMF, federal multi-flux, and quite a few others.

Sigh.