I've lost many a 262 because someone flys right into my bullet stream because he wants a kill.
Symptom: Losing 262s due to people flying into one's own bullet stream because those people want a kill.
Diagnosis: General target-fixation and loss of awareness due to wanting a kill for oneself, and thus, oblivious of the possible dangers of firing upon friendly aircraft in the vicinity. Also may be associated with greed, lack of cooperation, and desire to monopolize every possible kill as one's own.
Conclusions: Entirely one's own fault. The concept of "Situational Awareness" includes not only that of the enemy, but also that of the friendly. Since MA lacks the forced cooperation, and general chain of command as seen in real military organizations, the responsibility to coordinate attacks amongst friendly units in the vicinity falls upon the shoulder of each and every player of the game. If but only one of the two people in the air were minding his surroundings, the described accident would never have happened. Since you can't force anyone to do anything in this game, there is always a possibility of such instances happening, and thus, it is up to oneself to try and avoid such incidents from happening.
In other words,
... look before you shoot.