Maintenance Airframe; Maintenance Powerplant
Situational Awareness
Deviation / Discrepancy - Procedural Published Material / Policy; Ground Event / Encounter Loss Of Aircraft Control; Ground Event / Encounter Object
Aircraft Aircraft Damaged; Flight Crew Regained Aircraft Control; General Maintenance Action
Human Factors; Procedure
During a high power performance run; at approximately 96% torque; the parking brake handle released and the plane lurched forward; jumping the chocks. The left engine struck the GPU and damaged the #1 propeller. The aircraft movement was stopped by applying the toe brakes; retarding the throttles and reapplying parking brake. [In the future] chock all three gear; remove GPU from run area.
A Maintenance Technician described an engine high power run where the parking brake became released; which resulted in the propeller contacting a piece of ground equipment.