Because the fuel tanks were not full the tanks did not exploded. Was the aircraft hit at departure it could be much worse.
Huh?
A full tank is more likely to explode than a partially empty one?
Doesn't a partially empty tank have more fumes in it?
And, aren't the fumes the explosive bit?
And, doesn't it depend on what they're shooting?
If they're shooting bullets, there's not much chance of blowing up a fuel tank. But if they're shooting explosive ordinance, it wouldn't matter much how much fuel is in the tanks, there would be an explosion.