Air medical jets carry large oxygen tanks for patient care. The combination of pure oxygen and jet fuel makes for a rather large explosion.

Not just fuel, but large tanks of pure oxygen. Air medical aircraft carry large O2 tanks for patient care. The combination of fuel and oxygen makes for a very large explosion.

Air medical flights carry large oxygen tanks for patient care. The oxygen tanks combined with the fuel make for a much larger explosion than a standard plane crash. If they had departed recently, both the fuel and the oxygen would have been full.