Tower Alert System Cited In Fatal Crash

The “inadequate design and function” of the Minimum Safe Altitude Warning System in an FAA airport tower was cited as a contributing factor by the NTSB in its final report on the fatal crash of a Mitsubishi MU-2B-60 in Colorado in August 2005. The approach controller handed off the flight to the tower when it was about 10 miles out, but the tower controller’s radar display issued an aural alarm to warn of terrain conflict only within five miles of the airport. The discrepancy meant the tower controller was not warned until it was too late. The commercial pilot, who was flying cargo, was attempting a precision instrument approach at about 2 a.m. in instrument meteorological conditions when the airplane collided with terrain about four miles short of the runway. The pilot’s failure to fly a stabilized approach was cited as the main cause of the crash. The FAA’s inadequate procedure for informing controllers about the operating parameters of their system was cited as another contributing factor.