CEN12LA387 · Cessna R182

According to the pilot, before turning onto a base leg in the airport traffic pattern, he lowered the landing gear and selected the flaps to 10 degrees. He reported that the green landing gear position light illuminated after the landing gear extended and that, while on the base leg, when he selected the flaps to 20 degrees he visually confirmed that the left main landing gear was extended. Shortly after touchdown, the left main landing gear began to retract, followed by the right main landing gear. The airplane then veered off the left side of the runway. During the postaccident recovery, as the airplane was lifted off the ground, the main landing gear fully extended, without electrical power supplied, into the down-and-locked position. The landing gear was checked and all three down-lock assemblies appeared to be properly engaged. The airplane was subsequently placed onto jack stands, and no anomalies were observed as the landing gear was cycled several times using the airplane's electro-hydraulic system. Testing of the landing gear position indicating system confirmed that the green position light would not illuminate until all three landing gear were fully extended into a down-and-locked position. The postaccident examination did not reveal any mechanical malfunctions or failures that would have resulted in the main landing gear collapse. In the absence of landing gear extension system mechanical failures or malfunctions, and given the collapse of the main landing gear upon touchdown, it is likely that the landing gear was still transitioning into to a fully extended position at touchdown. Although contrary to the pilot’s account of the accident sequence, the most likely accident scenario is that the pilot did not extend the landing gear with sufficient time to ensure that it fully extended before landing.

Verbatim NTSB analysis and probable cause from the NTSB dataset