Comair

Embraer EMB-120 Brasília

The flight was being vectored for the approach to runway 3R at Detroit Metropolitan Wayne County Airport (DTW) when the aircraft descended and impacted the ground. The aircraft struck the ground in a steep nose-down attitude in a level field in a rural area about 19 nm southwest of DTW. The flight carried 26 passengers and 3 crew members. There were no survivors and the airplane was destroyed by impact forces and a post crash fire. Instrument meteorological conditions prevailed at the time of the accident. The investigation revealed that it was likely that the airplane gradually accumulated a thin, rough glaze/mixed ice coverage on the leading edge deicing boot surfaces, possibly with ice ridge formation on the leading edge upper surface, as the airplane descended from 7,000 feet mean sea level (msl) to 4,000 feet msl in icing conditions, which may have been imperceptible to the pilots. The pilots had been instructed by air traffic control to slow to 150 knots and according to flight data recorder information, the airplane began to show signs of departure from controlled flight as it decelerated from 155 to 156 knots while in a flaps-up configuration. The investigation disclosed that the FAA failed to adopt a systematic and proactive approach to the certification, and operational issues of turbopropeller-driven transport airplane icing. The icing certification process has been inadequate because it has not required manufacturers to demonstrate the airplane's flight handling and stall characteristics under a sufficiently realistic range of adverse ice accretion/flight handling conditions. The aircraft manufacturer had issued a revision in April, 1996 to the approved flight manual which included activation of the leading edge deicing boots at the first sign of ice formation. The airplane operator did not incorporate the procedure, because it was contrary to the company's trained procedures and practices and of the belief that enacting the changes would result in potentially unsafe operation. Investigators' discussion with management personnel at each of the seven U.S.-based operators of the aircraft indicated that at the time of the accident only two of these operators had changed their procedures to reflect the information in the revision. The FAA, at the time of the accident, did not require manufacturers of all turbine-engine driven airplanes to publish minimum airspeed information for various flap configurations and phases and conditions of flight. During Safety Board investigators postaccident interviews with company pilots, there were inconsistent answers on the complex and varied minimum airspeed requirements established by the company for both icing and nonicing conditions. It was also noted that the pilots uncertainty of the appropriate airspeeds might have been associated with the language used, the different airspeeds and criteria contained in the guidance, the company's methods of distribution, and the company's failure t o incorporate the guidance as a formal, permanent revision to the flight standards manual.

Swearingen SA227 Metro III

The pilot, a company check airman, and an FAA inspector were on board the aircraft for a checkride which was intended to reassess the pilot's competency. A maintenance test (aileron rigging) was to be performed in conjunction with the check ride. The first maneuver to be performed was a no-flap landing. All three pilots stated that the pilot had difficulty managing the aircraft while in the traffic pattern; airspeeds were too slow, and the pilot was constantly manipulating power. The pilot never called for the before landing checklist, and the aircraft touched down on the runway with the landing gear up. The check pilot stated that the landing gear warning horn came on briefly, but the pilot added power and silenced the horn. The FAA inspector was seated in a passenger seat for takeoff and landing, and was not aware that the landing gear was not extended.

Piper PA-31-310 Navajo

The twin engine airplane was engaged in a schedule service (flight OH444) from Cincinnati-Northern Kentucky Airport (Greater Cincinnati) to Nashville, carrying seven passengers and one pilot. After a roll of about 1,500 - 2,000 feet on runway 18, the pilot started the rotation. During initial climb, at an altitude of about 150 feet, the right engine lost power. The airplane entered a right turn then lost height and crashed in a field located 1,188 feet to the west of runway 18. The aircraft was totally destroyed by impact forces and all eight occupants were killed.