In-Flight Icing Encounter and
Uncontrolled Collision with Terrain
COMAIR Flight 3272
Embraer EMB-120RT, N265CA
January 9, 1997
NTSB Number AAR-98/04
NTIS Number PB98-910404
Synopsis: About 1554 eastern standard time, on January 9, 1997, an Empresa Brasileira de Aeronautica, S/A EMB-120RT, N265CA, operated by COMAIR Airlines, Inc., as flight 3272, crashed during a rapid descent after an uncommanded roll excursion near Monroe, Michigan. Flight 3272 was being operated under the provisions of Title 14 Code of Federal Regulations Part 135 as a scheduled, domestic passenger flight from the Cincinnati/Northern Kentucky International Airport, Covington, Kentucky, to the Detroit Metropolitan/Wayne County Airport, Detroit, Michigan. The flight departed Covington, Kentucky, about 1508, with 2 flightcrew members, 1 flight attendant, and 26 passengers on board. There were no survivors. The airplane was destroyed by ground impact forces and a postaccident fire. Instrument meteorological conditions prevailed at the time of the accident, and flight 3272 was operating on an instrument flight rules flight plan.
The National Transportation Safety Board determines that the probable cause of this accident was the Federal Aviation Administration's (FAA) failure to establish adequate aircraft certification standards for flight in icing conditions, the FAA's failure to ensure that a Centro Tecnico Aeroespacial/FAA-approved procedure for the accident airplane's deice system operation was implemented by U.S.-based air carriers, and the FAA's failure to require the establishment of adequate minimum airspeeds for icing conditions, which led to the loss of control when the airplane accumulated a thin, rough accretion of ice on its lifting surfaces.
Contributing to the accident were the flightcrew's decision to operate in icing conditions near the lower margin of the operating airspeed envelope (with flaps retracted) and Comair's failure to establish and adequately disseminate unambiguous minimum airspeed values for flap configurations and for flight in icing conditions.
The safety issues in this report focused on procedures for the use of ice protection systems, airspeed and flap configuration information, stall warning/protection system capabilities, operation of the autopilot in icing conditions, aircraft icing certification requirements, and icing-related research.
Safety recommendations concerning these issues were addressed to the FAA and the National Aeronautics and Space Administration. Also, as a result of this accident, on May 21, 1997, the Safety Board issued four safety recommendations to the FAA regarding EMB-120 minimum airspeed information, ice protection system operational procedures, and ice detection/warning systems.