Reason
As a professional pilot only one logical explanation comes into my head - on the last attempt pilots (bless them god) tried to land the plane in a very unusual but as they thought only one possible way - coming closer to runway deviate just a little bit below the profile to be able to see approach lights (if they are installed at that military place at all) or the RW itself and safely land there. But they came too low, maybe just by a couple of meters.....
All Aviation history is written on blood, sorry but this is true. I hope this lesson will and must be learnt by all professionals reading this very sad story..