Communiqués

TSB # A04-2002

(Gatineau, Quebec) 28 May 2002 - The Transportation Safety Board of Canada (TSB) today released its report on the investigation of a fatal accident 18 June 1998 at Mirabel / Montréal International Airport, Quebec, involving a Fairchild/Swearingen Metroliner II operated by Propair Inc. The report contains one recommendation dealing with the need for a brake system pressure warning indicator on SA226 and SA227 aircraft.

During the investigation, the TSB identified a number of safety deficiencies and made five recommendations in October 1998 dealing with

• wheel wells and wings overheating
• brake overheat detection and wheel well vulnerability
• hydraulic fluid mixing

For the most part, these recommendations were implemented. However, the regulator considered one recommendation—dealing with the installation of a brake temperature system to provide timely overheat information to the crew—as too costly to implement.

The TSB did extensive research and found that, since 1983, landing gear failures, tire failures, flat tires, wheel fires, and loss of control on ground were frequent for SA226s and SA227s. Sixty-five of these occurrences involved circumstances similar to this accident and had the potential to result in tragic events.

Although the 1998 recommendations have resulted in important progress, flight crews are still not provided with an unambiguous alert of dragging brakes. Until crews have accurate information about this problem, the risk of fire will remain high and could result in crashes, fatalities, injuries, and property damage.

The Board believes that a brake system pressure warning indicator is absolutely necessary to ensure safety. The Board therefore recommends that:

• Transport Canada, the United States Federal Aviation Administration, and Fairchild explore options for SA226 and SA227 aircraft to be equipped with a brake pressure warning indicator for each main-wheel brake system.

[A02-03]

The aircraft took off from Dorval / Montréal International Airport at 7:01 a.m., Eastern daylight time, for Peterborough Airport, Ontario. About 12 minutes after take-off, the crew advised air traffic control (ATC) that they had a hydraulic problem and requested clearance to return to Dorval. Around 7:19, the crew advised ATC that the left engine had been shut down because it was on fire. Around 7:20, the crew decided to proceed to Mirabel. At 7:23, the crew advised ATC that the engine fire was out. On final approach for Runway 24, the crew advised ATC that the left engine was again on fire. When the aircraft was over the runway on final approach, the left wing broke upwards, and the aircraft rolled and then struck the ground. The nine passengers and two pilots suffered fatal injuries.

The investigation into the crash found that the crew took off unaware that residual pressure remained in both brakes of the left landing gear brake system during the taxi and the take-off roll. During the take-off roll, the heat generated by the two dragging brakes increased exponentially. As a result, a brake seal failed, allowing brake fluid to leak onto the hot brake components and ignite, creating a fire in the wheel well. The fire spread rapidly, eventually causing the wing structure to fail in flight.

The Transportation Safety Board of Canada is an independent agency operating under its own Act of Parliament. Its sole aim is the advancement of transportation safety. It is not the function of the Board to assign fault or determine civil or criminal liability.

-30-