There are two references to "Hangar 18" in this post, one being a musical number and the other a 1980 film starring Robert Vaughn. Refence to Hangar 18 tends to pop up when reading about "Roswell" or "Area 51" alien spacecraft conspiracy theories [wiki], although the location of the hangar tends to move around a bit.
"Hangar 18" - Megadeth - Copyright restrictions mean you'll have to watch the video on Youtube [ youtu.be/4tzWc3Xl4B0 ]
I remember watching this as a child on the MTVs back in 1990. I thought it was the most sophisticated thing ever made for music television, and one of the spookiest things too! Looking at it now I'm cringing under the desk, although to be fair, the photography isn't bad, and I've seen B-Movies that weren't as much fun. Headbangers Ball on MTV used to always make a big deal out of it.
According to Wikipedia [wiki], it reached #25 in the Irish Singles Chart, which isn't surprising as Megadeth were quite popular here at the time. It's also reported that "Holy Wars... The Punishment Due", the opening track from the "Rust in Peace" album which Hangar 18 was included on, was inspired by the troubles in Northern Ireland, and given a twist with the troubles over Palestine/Israel.
The Wikipedia entry also says that the Hangar 18 song may have been inspired by the following film.
Watch the entire "Hangar 18" (1980) film on Youtube [ youtu.be/xfNh1daJ6ms ]
The second reference to "Hangar 18" is the film of the same name, released in 1980 [imdb]. An enjoyable little feature, but the a plot so far fetched it's out past Orion's Belt (and no, not because it's about space aliens). Two NASA astronauts watch a fellow astronaut get killed when the satellite they are deploying collides with a UFO whizzing around the planet. Rather than being held and thoroughly questioned by the US government and NASA, and kept out of public view (perhaps with a phoney quarantine notice), instead they are made scapegoats for their colleagues death and are subsequently turfed out on their ears. Well, I'm sure you can guess what happens next. Yes, the film becomes a cross between The Fugitive and intergalactic Magnum PI.
The opening scene was quite daring in a sense because it depicted the first deployment of a satellite, from the then unflown US Space Shuttle, where one of its crew members dies during the mission. How they got away with including that scene is testament to NASA's lack of superstition involving space flights. That or they just didn't care. Things went a little differently six years later when a family film about the Space Shuttle, "Space Camp" (1986) [imdb], was chalked for release just after the "Challenger disaster" [wiki] of that year, and had the release date put back to the Summer months.
Other noteworthy points about the film Hangar 18: A fun performance by Darren McGavin [imdb], who also stared in another 1980 NASA related production, The Martian Chronicles [imdb]. Also the sub-story of the aliens is clearly an influence on this year's Prometheus [imdb] film. The aliens even look a bit like the Engineers.