Ya know, the old custom of naming an airplane was seen as kinda “old school” after Vietnam (that wasn’t a good thing back then; anything military was seen as evil, Neanderthal, disreputable). The custom died for a few years, while the military made some HUGE mistakes in PR and image-polishing.
The military mind was convinced that it had to be more “scientific”, more like a business. It tried to be politically correct, to project an image that said, “We take no joy in this profession, but somebody has to do it.” In that day and age, something flippant like naming weapons systems just smacked of “Laughing Cavaliers” and “Happy Warriors” a bit too much, and the generals went completely overboard convincing people that warriors approached their profession reluctantly.
It was a disaster, and a few years ago, it began to change. In the meantime, it had almost ruined the military’s culture, a uniqueness that binds the people together, and makes them a cohesive team.
One of the things that was re-introduced was the concept that it wasn’t a weapons system, it was a magic carpet. A $30 million-dollar magic carpet that did amazing things to protect our country. It was owned by it’s unit, and they were proud of it. It was babied and cossetted and bragged about, and you can’t very well do that with something known by a serial number. “NEGATIVE, sir, that’s MY airplane, and I’ll thank you to call her by her given name, ‘Helluva Roar’, and not THREE-OH-SIX, like she was a goddam’ item off a goddam’ Chinese fuckin’ menu! Sir.” (Crew chiefs are kinda salty, sometimes.)
Most units have a tradition of where their plane’s names come from. For instance, the B-2s at Whiteman Air Force Base, Missouri, are all ‘Spirit of [American city]’. Fighter units usually name their airplanes something pugancious and aggressive, and the pilots, commanders, crew chiefs, or any combination may name 'em, depending on that unit’s tradition.