The jet appears to have trouble climbing into any kind of air speed. That was the problem it didn't achieve airspeed to carry it's weight. The pilot was struggling with it from the beginning. It didn't have enough air speed. What was that all about?
A jet won't fly without sufficient air under it's wings. This jet simply stopped. The turbines didn't have enough air flowing through them.
The explosion was because the tanks were full. It was anticipating a lengthy flight and/or using a lot of fuel to make it's trip.
By ALISSA J. RUBIN
Published: April 29, 2013
...There was no information (click here) late on Monday about whether the plane was carrying cargo or its intended destination. It belonged to National Air Cargo, a military contractor based in Orchard Park, N.Y., outside Buffalo. Military officials said that the cause of the crash was being investigated, but that there had been no enemy activity in the area at the time.