An American Airlines MD-83 descended below minimum altitude guidelines on final approach to Bradley International Airport (East Granby, CT) when the flight crew failed to observe their altitude during a rain storm violent enough to cause the closure of Bradley's air traffic control tower, the National Transportation Safety Board said today. Their action led to a hard landing that substantially damaged the aircraft.
Just after midnight on November 12, 1995, a McDonnell Douglas MD-83, operated as American Airlines flight 1572 from Chicago, was substantially damaged when it impacted trees while on approach to runway 15 at Bradley International Airport (BDL). The airplane also hit an instrument landing system antenna as it landed short of the runway on grassy, even terrain. There were no injuries.
At a public meeting today in Washington, D.C. the NTSB determined the probable cause of this accident to be the failure of the flight crew to observe minimum altitude guidelines on their final approach during an instrument landing. Contributing factors were the failure of the airport approach controller to furnish the flightcrew with a current altimeter setting and the crew's failure to ask for a more current setting. Despite weather conditions severe enough to force the closure of the airport's control tower, the Board did not find conditions to warrant the crew's departure from minimum altitude.
In an effort to prevent future accidents, the Board recommended that the Federal Aviation Administration evaluate design criteria for non-precision approaches, incorporating for the Bradley International Airport specifically terrain adjustments on the runway approach being flown by flight 1572. The Board also recommended that the FAA evaluate the Terminal Instrument Procedures (TERPS) design for non-precision approaches to consider incorporating a constant rate or angle of descent in lieu of the "step-down" criteria currently used.
Further, the FAA should solicit and record flightcrew comments about difficulties encountered in flying a particular approach and require controllers to issue to flighcrews as frequently as practical altimeter setting changes whenever the official weather report includes the phrase "pressure falling rapidly."
The Board also examined emergency exit procedures and recommended that the FAA develop a uniform policy on shoe removal during emergency evacuation and require all MD-80 and DC-9 operators to inspect floor level exits for properly rigged evacuation slides.
The NTSB's complete report, PB96-910405, may be purchased from the National Technical Information Services, 5285 Port Royal, Springfield, VA 22161, (703) 487-4650.