Aircraft: Cessna 182. Injuries: None. Location: Houston, Texas. Aircraft damage: Substantial.
What reportedly happened: The pilot, who was returning to the airport after a short flight, performed the before-landing checklist, which included verification of landing gear extension. After touchdown both main landing gear legs collapsed. The nose gear remained extended and the airplane slid down the runway.
The subsequent examination of the airplane revealed that the electric motor that actuated the hydraulic power pack was inoperative. The failure of the power pack before the end of the gear extension cycle would result in a fully extended nose gear and a partial extension of the main landing gear legs.
Probable cause: The failure of the landing gear to fully extend and lock in the down position due to the inoperative electric pump motor.
NTSB Identification: CEN11CA155
The gear legs didn’t collapse–the pilot didn’t check that the “gear down” light was illuminated. All Cessna retractable gear singles are equipped with a back-up method of extending the landing gear if the primary power source ( engine driven pump or electrically driven pump) fails.
I suspect the pilot selected gear down but didn’t visually check (you can see the main gear wheels when extended) for a green lite. I had that happen once during an instrument approach in a 182RG. No green light and no gear in spite of selecting gear down. A few strokes of the emergency gear down pump handle brot the gear out and locked promptly.