Canada's TSBa Determines That Modifications To A Display Manoeuvre Caused The In-Flight Collision

Canada's TSB has released its final report (A05C0123) into the in-flight collision between two biplane aircraft participating in the Saskatchewan Air Show in Moose Jaw, Saskatchewan, on July 10, 2005.

The investigation revealed that the collision occurred as the aircraft were executing a modified version of the Dairy Turn, a manoeuvre originally conceived to create the illusion of a near collision for spectators. The display involved three biplanes that were used to perform a simulated dogfight. The biplanes would execute crosses that were planned to ensure safe separation. The modified manoeuvre did not ensure safe execution.

On July 10, 2005, three United States-registered aircraft were engaged in a simulated dogfighting display at Moose Jaw/Air Vice Marshal C.M. McEwen Airport as part of the Saskatchewan Air Show. The display team, called the Masters of Disaster, consisted of three biplane aircraft (a Waco, a Wolf-Samson and a Pitts Special). A ground display featuring a jet-powered truck was part of the act. The three biplanes were performing a series of crosses and chases in a simulated dogfight scenario. As the jet-powered truck moved into position on the show line, the three biplanes entered a manoeuvre in preparation for a series of crosses centred on the truck. During the manoeuvre, the Waco and the Wolf-Samson collided, caught fire and crashed. Both pilots were killed at impact, and both aircraft were destroyed. All debris fell away from the crowd toward the outer runway. Immediate implementation of emergency procedures kept spectators from moving toward the burning wreckage.

The TSB is an independent agency that investigates marine, pipeline, railway and aviation transportation occurrences. 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.

TSB Final Report Excerpts:

Findings as to Causes and Contributing Factors

1. The Dairy Turn manoeuvre had been modified such that a temporary loss of visual contact could occur immediately before the aircraft crossed flight paths. This modification made timing critical and added two potential points of collision.
2. The manoeuvres immediately before the collision indicated that the performers had not established a clearly understood contract for the revised manoeuvre. The actions of each performer negated the actions of the other, and neither pilot took positive action to regain visual contact.
3. The timing of the manoeuvre was lost when the Waco turned late at show centre.

Finding as to Risk

The sequential manoeuvre information provided to Transport Canada was not detailed enough to allow a thorough review of the energy management of the display.

FMI: www.tsb.gc.ca, www.tsb.gc.ca/en/reports/air/2005/a05c0123/a05c0123.asp