On April 21, 1983, a Piper PA-23-250 (registration N6574Y) was involved in an aviation accident near Odessa, TX. Investigators recorded the probable cause as: The pilot's failure to ensure the landing gear was fully extended and locked prior to landing, despite reporting that the gear handle was down and three green lights were illuminated. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
Aircraft sustained substantial damage during a gear-up landing. The pilot reported extending the gear on base leg with three green lights illuminated, but could not recall hearing the warning horn.
What happened
The aircraft was substantially damaged during a gear-up landing. The pilot stated that the gear handle was put down on base leg and he had 3 green lights. He does not recall hearing a gear warning horn. When the aircraft was transported to a hangar the gear was up and the gear doors were closed. The gear was pumped down resulting in illumination of all three green lights.
The investigation
Upon arrival at the hangar, mechanics observed that the landing gear remained retracted with the gear doors closed. To verify the position of the gear indicators, the landing gear was manually pumped down. This action resulted in the illumination of all three green lights, confirming that the gear mechanism had engaged correctly despite the aircraft touching down on its belly.
Findings
The pilot reported extending the landing gear on base leg and observing three green lights. However, he did not recall hearing a gear warning horn. The discrepancy between the visual confirmation of gear extension and the lack of auditory warning suggests a potential failure in the warning system or a lapse in pilot awareness. The subsequent pumping of the gear confirmed that the mechanical linkage was functional, as indicated by the green lights illuminating upon extension.
Probable cause
The pilot's failure to ensure the landing gear was fully extended and locked prior to landing, despite reporting that the gear handle was down and three green lights were illuminated.