NTSB Identification: LAX97LA125.
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Accident occurred Monday, March 17, 1997 in FRESNO, CA
Probable Cause Approval Date: 05/21/1998
Aircraft: Cessna 425, registration: N425TV
Injuries: 3 Uninjured.
NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.
Two pilots and a mechanic were going on a postmaintenance test flight to check the ailerons following control system work. The aircraft maintenance records disclosed that the right brake master cylinder was replaced prior to this flight. In addition, the original PT6-112 engines had been replaced by new PT6-135's with new 4-bladed propellers. The company which installed the engines and props said that the engines and props had not been rigged following installation due to the aircraft's scheduled arrival at the paint shop. The rigging was an open item yet to be accomplished at the time of the accident. The pilot said that prior to engine start, he tested and held brakes. Following engine start, the right brake pedal slowly went to the floor, and the aircraft began moving forward and turning left. He attempted to pump the right pedal to restore brake pressure, but without success. A loaded Cessna Citation was directly ahead of the aircraft, and the pilot intentionally kept the aircraft turning left to avoid the jet as he moved the throttle levers into reverse to stop. When the aircraft failed to stop, he pulled the propeller levers into feather and the condition levers to stop. The aircraft continued to move during this process, and the left wing collided with the parked Cessna 425. Examination of the aircraft by FAA airworthiness inspectors revealed that the engine and prop rigging was out of spec to the point that the propeller blades would not move beyond a zero blade angle. Taxi tests disclosed no anomaly with the brakes, and the engines and propellers as rigged would not provide any braking or reverse thrust. Detailed examination of the aircraft revealed no evidence of brake fluid leakage. The right brake master cylinder was removed from the airplane and tested to factory specifications for a new cylinder.
The National Transportation Safety Board determines the probable cause(s) of this accident to be: failure of the right brake to function, due to the installation mechanic's failure to completely bleed all air from the lines. A factor in the accident was the pilot's decision to fly the unairworthy aircraft before the engine/propeller installation had been fully rigged and tested to specification. Full narrative available
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