Could someone really die in the way that Goose did in the movie "Top Gun"?
Some sources I found claiming the event was real:


  A flat spin creates a low-pressure area and stalls the canopy when
  ejected. Producers wanted a midair crash but based this accident on a
  real-life incident instead.


(source)


  The way Goose died was actually based on a real life incident that
  happened to a 14 crew in the Navy. Don't remember the specifics, just
  found this out recently while reading an article in one of last months
  flying mags (not Flying)


(source)


  I have a photo of the 'real' Goose and it's true that he died of seat
  ejections but not exactly like the movie.


(source, with pictures)

There's also an interview of Steven C. Schallhorn, who apparently was one of top gun instructors interviewed for the movie:


  Dr. Schallhorn said during his interview for the movie, he explained
  how a flat spin could actually happen with an F-14 and that it
  complicates ejection. "The aerodynamics of the F-14 flat spin affect
  the timing of the ejection sequence," Dr. Schallhorn said. "The canopy
  is jettisoned, followed by the ejection of the back seat, followed by
  the front seat. In a flat spin, the canopy, when it ejects, bobbles
  for an extra few hundredths of a second above the aircraft. That
  upsets the carefully engineered sequence because the guy in the back
  could then hit the canopy. That sequence made it into the movie."


(source)