On 31 December 2009, a Cessna Aircraft Company model
208, registered VH-UMV, was engaged in parachuting operations from
Cairns Airport, Queensland. While climbing through 12,500 ft in
preparation for a parachute drop, the engine failed. The
parachutists exited the aircraft and the pilot completed a glide
approach and uneventful landing at Cairns Airport.
The failure of the Pratt and Whitney PT6A-114 engine
was probably precipitated by fracture of the compressor turbine
blades. Federal Aviation Administration (FAA) parts manufacturing
approval information indicated that part number T-102401-01
compressor turbine blades that had been installed in the engine
during the most recent overhaul were not approved for the PT6A-114
model.
As a result of this occurrence, the Civil Aviation
Safety Authority (CASA) released Airworthiness Bulletin AWB 72-005,
alerting all operators and maintainers of PT6A engines, of the
potential for installation of these compressor turbine blades in
unapproved PT6A engine variants, and to raise awareness of the
restrictions placed on the use of approved after-market blades.