'Unknown reasons' led to crash that killed MRU aviation instructors, TSB report concludes

The Transportation Safety Board says it doesn't know what caused a small plane crash near Calgary last year that killed two flight instructors from Mount Royal University.

'The aircraft entered a spin from a stall exercise ... insufficient altitude remained to recover'

Mount Royal University aviation instructors Jeffrey Bird, left, and Reynold Johnson, were killed in a plane crash near Waiparous on Feb. 13, 2017. (Facebook/Mount Royal University)

The Transportation Safety Board (TSB) says it doesn't know what caused a small plane crash last year that killed two flight instructors from Mount Royal University.

Reyn Johnson, 64, and Jeffrey Bird, 35, both died when the twin-engine Tecnam P2006T they were flying went down northwest of Calgary about 30 minutes into an instructional flight on Feb. 13, 2017.

"The investigation found that for unknown reasons, the aircraft entered a spin from a stall exercise. The instructor and trainee recovered the aircraft from the spin, but insufficient altitude remained to recover from the ensuing dive," the TSB says in its investigation report, which was released Thursday.

The TSB noted that the angle of attack is important in stall exercises, and if the reduction of the angle isn't correct a loss of aircraft control may occur.

The Mount Royal aviation program has brought in a number of safety changes since the crash, including increasing the minimum altitude at which pilots perform manoeuvres to 4,000 feet above terrain, and acquiring a different type of aircraft for its multi-engine training program.

Dr. Elizabeth Evans, dean of MRU's faculty of business and communication studies, which includes the aviation program, said the school has also implemented an online program allowing students and instructors to self-report safety issues.

Instructors have also been told to stop using a non-standard technique for recovering from a stall, said Evans.

"We are aware that the instructors had discussed certain manoeuvres that they had been developing or doing, but we have no confirmation of those being reported to us," she said. "Now that those have been identified … the instructors were certainly made clear that was not to be continued."  

Investigators had already determined that the Tecnam climbed to 8,000 feet above sea level and then headed to the northwest. The last radar contact from the plane was recorded at 7,900 feet.

The aircraft hit the ground 32 nautical miles northwest of the Springbank Airport, where the MRU flight program is based.

All of the major aircraft components were found at the accident site but were destroyed by the crash impact and a post-impact fire, the TSB said.

The Tecnam the men were flying was one of three twin-engine aircraft owned by Mount Royal. The school also has five single-engine Cessna 172s in its fleet.