FTW98LA139

During the landing roll, the nose gear collapsed. On a previous flight and during the approach on this flight, the aircraft experienced a total electrical failure. Following the first electrical failure, the battery was replaced by company maintenance personnel and the electrical system checked operational per the manufacturer procedures. The airframe Maintenance Manual inspection checklist states in part: Inspect wiring to engine and accessories, replace damaged wires and clamps, and inspect terminals for security. The section of the maintenance manual describing servicing the electrical system in part states: 'The security of all electrical connections should be checked.' Examination of the accident airplane revealed that the output lugs were broken off both alternators. NTSB Metallurgical examination of the fracture surfaces revealed 'no discernable fracture features. Both parts contained evidence of electrical arcing that caused significant melting of the separated ends.' A post-accident landing gear retraction test revealed no evidence of discrepancies with the landing gear system. Time since the last annual inspection was 12.7 hours.

On February 24, 1998, at 1535 central standard time, a Piper PA-46-350P airplane, N9254X, sustained substantial damage following a total electrical failure and a nose gear collapse during the landing roll at Dallas Love Field, Dallas, Texas. The airplane, owned by JRW Aviation, Inc., Dallas, Texas, was operated under Title 14 CFR Part 91. The commercial pilot, sole occupant, was not injured. Visual meteorological conditions prevailed for the personal cross country flight and a flight plan was not filed. The flight originated at Lampasas, Texas, approximately 1430.

During telephone interviews, conducted by the investigator-in-charge, the director of maintenance and the pilot reported that 3 days prior to the accident, the aircraft was landed at Lampasas following a total electrical failure. The battery was replaced by company maintenance personnel and the electrical system checked operational per the manufacturer procedures. The flight departed Lampasas and the pilot was receiving vectors for a visual approach to the downwind position for runway 13L at Dallas Love Field when the aircraft lost all electrical power. The pilot performed the emergency landing gear extension procedure; however, the position of the gear could not be confirmed due to the electrical failure. The nose gear collapsed during the landing roll.

The FAA inspectors and a mechanic examining the airplane found structural damage to the airframe at the area where the nose landing gear trunion mounts. The propeller and nose gear doors were damaged. Under the surveillance of the FAA inspector on March 10 and March 18, gear retraction tests were performed by the director-of-maintenance and the manufacturer representative. The landing gear "checked okay during normal and emergency extension. No interference of any kind affected the operational check." During the removal of the engine, it was found that the output lugs were broken off both alternators. The two output lugs were forwarded to the NTSB Metallurgical Laboratory.

Metallurgical examination of the output lug fracture surfaces revealed "no discernable fracture features. Both parts contained evidence of electrical arcing that caused significant melting of the separated ends."

A review of the maintenance records by the investigator-in-charge revealed that the last annual inspection was performed on January 21, 1998. At that time the nose gear up-roller, bushing, spring, and bolt were replaced and gear retraction tested. The airplane was determined to be in an airworthy condition. Time since the annual inspection was 12.7 hours.

The Piper Aircraft Maintenance Manual (Chapter 5-20-00) inspection checklist includes the following items: Inspect wiring to engine and accessories. Replace damaged wires and clamps. Inspect terminals for security. Inspect alternator(s) for cracks, condition, and security. Check alternator output. The section of the airframe maintenance manual describing the servicing of the electrical system (Chapter 12-10-00) in part states: "The security of all electrical connections should be checked."