20010908025439A

(-23) Pilot taxied out and completed runup adjacent to DHC-8 aircraft. Pilot waited for 816PH to depart, believing it was a passenger flight preparing to leave. When it did not depart pilot called for, and received, a takeoff clearance. The pilot did not know that the DHC-8 was controlled by maintenance personnel, conducting a maintenance power test. As there was not enough room to taxi in front of the DHC-8 the pilot taxied behind the aircraft. The pilot indicated that as he began to taxi the DHC-8 was at low power, but as he taxied behind the aircraft the power suddently increased on one engine, and his aircraft was blown over onto the left wing and nose of the aircraft, resulting in substantial damage. Subsequent investigation yielded that the maintenance crew aboard the DHC-8 failed to maintain radio communication with the tower, and was at no time aware of the Cessna 172 aircraft in their proximity. An airport fire truck was dispatched to the DHC-8 to get their attention, flashing lights until the crew looked up and responded. The maintenance crew was then notified that the tower had been trying to contact them.