What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
Inflight breakup IFR enroute in area moderate mixed icing. Design loads exceed in descending spiral or spin. (.4) the airplane was cruising on a southerly heading at 13,000 feet, in instrument meteorological conditions, when, over a 23-second period, it turned toward the west, descended about 1,200 feet, then broke up. The last 3-point smoothed ground speed calculation for the airplane indicated 242 knots. Winds aloft were from the east, about 10 knots. The airplane's maximum operating speed was 167 knots indicated, and maximum maneuvering speed was 141 knots indicated. At the time of the accident, the airplane was in conditions conducive to icing. The airframe anti-icing system was inoperative, and it was undetermined whether the engine and pitot ice protection systems had been activated. The horizontal stabilizer and the wings exhibited markings consistent with downward overstress separation. The flight originated from hamilton, ontario, and stopped at buffalo, new york, before continuing. An AIRMET, calling for icing, was in effect, but not mentioned during the ontario weather briefing. In buffalo, no flight service station services were requested or provided. Flight into icing conditions in the accident airplanes was prohibited, and the procedures was to turn back or change attitude to escape the icing.
As the FAA filed it
INFLIGHT BREAKUP IFR ENROUTE IN AREA MODERATE MIXED ICING. DESIGN LOADS EXCEED IN DESCENDING SPIRAL OR SPIN. (.4) THE AIRPLANE WAS CRUISING ON A SOUTHERLY HEADING AT 13,000 FEET, IN INSTRUMENT METEOROLOGICAL CONDITIONS, WHEN, OVER A 23-SECOND PERIOD, IT TURNED TOWARD THE WEST, DESCENDED ABOUT 1,200 FEET, THEN BROKE UP. THE LAST 3-POINT SMOOTHED GROUND SPEED CALCULATION FOR THE AIRPLANE INDICATED 242 KNOTS. WINDS ALOFT WERE FROM THE EAST, ABOUT 10 KNOTS. THE AIRPLANE'S MAXIMUM OPERATING SPEED WAS 167 KNOTS INDICATED, AND MAXIMUM MANEUVERING SPEED WAS 141 KNOTS INDICATED. AT THE TIME OF THE ACCIDENT, THE AIRPLANE WAS IN CONDITIONS CONDUCIVE TO ICING. THE AIRFRAME ANTI-ICING SYSTEM WAS INOPERATIVE, AND IT WAS UNDETERMINED WHETHER THE ENGINE AND PITOT ICE PROTECTION SYSTEMS HAD BEEN ACTIVATED. THE HORIZONTAL STABILIZER AND THE WINGS EXHIBITED MARKINGS CONSISTENT WITH DOWNWARD OVERSTRESS SEPARATION. THE FLIGHT ORIGINATED FROM HAMILTON, ONTARIO, AND STOPPED AT BUFFALO, NEW YORK, BEFORE CONTINUING. AN AIRMET, CALLING FOR ICING, WAS IN EFFECT, BUT NOT MENTIONED DURING THE ONTARIO WEATHER BRIEFING. IN BUFFALO, NO FLIGHT SERVICE STATION SERVICES WERE REQUESTED OR PROVIDED. FLIGHT INTO ICING CONDITIONS IN THE ACCIDENT AIRPLANES WAS PROHIBITED, AND THE PROCEDURES WAS TO TURN BACK OR CHANGE ATTITUDE TO ESCAPE THE ICING.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.
Other reports on N72141 · 1
Matched to the same aircraft by N-number and date.