Casualties unknown

Landing Gear Collapse After Electrical Failure Due to Voltage Regulator Malfunction (N1959P)

Tacoma, WA, US

On November 3, 2005, a Piper PA-24-250 (registration N1959P) was involved in an aviation accident near Tacoma, WA. Investigators recorded the probable cause as: Loss of electrical power due to a malfunctioning voltage regulating system, which prevented the landing gear from fully extending, and the pilot's failure to use the emergency gear extension system. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 2026-06-10Data APIEditorial standards

A pilot experienced a complete loss of electrical power after a voltage regulator malfunction, preventing gear-down confirmation. Despite a low pass and go-around, the landing gear collapsed on touchdown after the pilot did not use the emergency extension system.

Accident Sequence

After making contact with the tower and receiving clearance for a left base entry, the pilot completed the before-landing check and lowered the landing gear. He then attempted to call the tower to report entering the base leg but realized his radio was not transmitting. The aircraft subsequently experienced a complete loss of electrical power. Unable to confirm the gear was down and locked because the green Gear Down lights could not illuminate, the pilot flew low over the runway until he felt the main wheels touch the surface, then executed a go-around.

Following the go-around, the pilot entered the pattern and performed what he believed would be a normal full-stop landing. However, just after touchdown, the landing gear folded back into the wheel wells, causing the aircraft to skid down the runway on its belly.

Investigation Findings

Post-accident investigation determined that the landing gear had not fully extended because of the loss of electrical power. Additionally, although the aircraft's battery and alternator were capable of normal operation, the voltage regulating system had malfunctioned, allowing the battery to become almost fully discharged. The pilot did not use the emergency gear extension system or sequence to verify the position and condition of the landing gear, instead relying solely on the sensation of the tires touching the runway during the low pass to assume the gear was down and locked.

Probable cause

Loss of electrical power due to a malfunctioning voltage regulating system, which prevented the landing gear from fully extending, and the pilot's failure to use the emergency gear extension system.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20051216X01984. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.