Piper PA-24-250 N6195P accident near Mckinney, Texas

Probable cause

Collapse of the landing gear for reasons that could not be determined because visual examination did not reveal any mechanical malfunction or failure that would have prevented the gear from locking in the extended position and postaccident damage precluded functional testing.

NTSB analysis

The pilot stated that he attempted to contact the air traffic control tower for a landing clearance but was unable to. He circled in the area to troubleshoot the problem and determined that the radios were not transmitting. The air traffic controllers in the tower saw the airplane circling and radioed that the pilot was cleared to land. The pilot turned toward the airport, at which time a total loss of electrical power occurred. The pilot and passenger, who was the airplane owner, were unable to identify the cause of the electrical failure. The pilot selected the landing gear to the down position, and the passenger performed the landing gear emergency extension checklist. The pilot reported hearing the gear extend and asked the passenger if the gear appeared to be down and locked; the passenger replied yes. The landing gear collapsed when the airplane touched down, and the airplane slid about 200 feet before coming to rest.

A postaccident visual examination of the landing gear did not reveal any mechanical failure or malfunction that would have prevented the gear from locking in the extended position. An annual inspection of the airplane had been completed about 1 month before the accident flight during which new bungee cords were installed on the landing gear, in accordance with an airworthiness directive. The landing gear system, including the emergency extension system, was reportedly operationally checked during the annual inspection without any anomalies noted. Due to damage sustained in the accident, the landing gear could not be functionally tested; therefore, the reason for its collapse could not be determined. Although the airplane battery did not hold a charge during postaccident testing, the alternator functioned properly. Electrical power should have been available from the alternator once the engine was running, regardless of the condition of the battery. The reason for the electrical system failure could not be determined.

Text from the NTSB. Open the NTSB docket for CEN13LA141 for the full record.