As a long time former Viper maintainer (86-04) the Thunderbird crash looks like engine failure to me.
It might have been an engine failure....but why then did the T-Bird NOT burst into flame upon impact?
The Obummer being late story may makes sense.
The Academy web site says the graduation would end at 12:30 -
http://www.usafa.edu/superintendent/graduation/gradSchedule.cfm?catname=graduation
The article says the jet crashed at about 1 pm. right after the fly-by — 30 minutes of low level maneuvering while waiting for a “go” command must burn up more fuel than planned.