Arrow Air Flight 1285 - Investigation

Investigation

The Canadian Aviation Safety Board (CASB) investigated the crash, and, under the signature of five of nine board members, found that during its approach toward Gander, precipitation conditions were favorable for the formation of ice on the aircraft's wings. After landing, it continued to be exposed to "freezing and frozen precipitation capable of producing roughening on the wing upper surface" in addition to the freezing temperature. They also found that prior to takeoff the aircraft had not been de-iced. The Board issued the following Probable Cause statement in its final report:

The Canadian Aviation Safety Board was unable to determine the exact sequence of events which led to this accident. The Board believes, however, that the weight of evidence supports the conclusion that, shortly after lift-off, the aircraft experienced an increase in drag and reduction in lift which resulted in a stall at low altitude from which recovery was not possible. The most probable cause of the stall was determined to be ice contamination on the leading edge and upper surface of the wing. Other possible factors such as a loss of thrust from the number four engine and inappropriate take-off reference speeds may have compounded the effects of the contamination.

Four members of the CASB dissented, issuing a minority opinion asserting that there was no evidence presented proving that ice had been present on leading edges such as the wings, and the minority report speculated that:

An in-flight fire that may have resulted from detonations of undetermined origin brought about catastrophic system failures.

The one piece of evidence that would show which one is correct was the Cockpit Voice Recorder (CVR). However, this device was defective and failed to record anything. Also, the Flight Data Recorder (FDR) was an older model that only recorded 4 parameters. It was scheduled to have been replaced a few weeks later.

Willard Estey, a former Supreme Court of Canada judge, submitted a review of the CASB report in 1989, ruling that the available evidence did not support either conclusion. As a result the Canadian public's confidence in the CASB was undermined. The federal government responded by creating the Transportation Safety Board of Canada.