My original idea involved a hijacked C-130, an experimental device activated, and the A/C transported to an alternate dimension (where it promptly crash-lands). I could still go this route but I feel like alternate reality sci-fi has been clubbed to death.
The elements of the story that I've decided upon are:
1. Artsy-fartsy guy falls in love with and gets engaged to an Air Force officer. She is the chief research scientist involved in experimental weaponry for the military. On the initial activation flight, the test bed platform (C-130, B1-B, etc) disappears.
2. The artist is told the A/C crashed with all hands lost. There is something about the official story that doesn't add up, so he becomes obsessed with discovering the truth.
3. Either the artist pursues the investigation entirely on the outside or he joins the Air Force himself. Either way, he eventually ends up with another version of the experimental weapon, hijacks a test bed, and attempts to cause the same anomaly.
4. The artist ends up in an alien world/alternate universe with anime chicks and robots and stuff. He gets hints that his financee may still be alive, and begins his search.