The crash of an F-15 military aircraft near Vincennes in May is being blamed on mechanical failure. Investigators say an interconnect crossover cable jammed, causing the crash. That cable transfers a pilots flight control inputs to the aircraft. Military officials say the flight controls became unresponsive about 20 minutes into the training exercise. They also report the jets altitude, when the problem occurred, made it impossible for the pilot to correct the situation. No one was injured, but the $43 million plane was destroyed in the crash.