Pedestrian didn't hear helicopter that killed him because of headphones (aftermath video)

May 13, 2008 - Cranbrook, B.C. An investigation into a helicopter crash last year in Cranbrook, B.C., that killed four people could find no reason for the sudden loss of power in the aircraft's engine, according to a Transportation Safety Board report released Thursday.

The single-engine Bell 206 helicopter crashed on a Cranbrook street on May 13, 2008, and burst into flames, killing pilot Edward Heeb, 57, and occupants Dirk Rozenboom, 45, and Robert Lehmann, 37.

Pedestrian Isaiah Otieno was also killed. The 20-year-old Kenyan student was walking to mail home a letter when the helicopter crashed on top of him. Otieno didn't hear the helicopter, witnesses said, because he was wearing headphones at the time.

The helicopter, owned by Bighorn Helicopters, had been contracted by BC Hydro to check power lines and was flying 30 to 40 metres above the ground before it crashed.

The helicopter was flying at a height and speed that would make it impossible to descend and land safely in the event of a loss of power, the report said.

The board's lead investigator, Damien Lawson, said Transport Canada would not have authorized the flight as the helicopter lacked the safety features of a twin-engined helicopter and was flying at a speed and altitude that made an autorotation landing impossible when the aircraft suddenly lost power.

Bighorn Helicopters did not apply for the authorization for the flight, Lawson said.