Narrative:

A single engine VOR/DME approach was being flown with the left engine at 11 inches of manifold pressure to simulate zero thrust. Upon reaching the FAF; the landing gear was extended and verified down and locked with no unsafe indications. The approach was continued to 1;300 ft; at which time I took the controls from the student so that he could remove his view limiting device. The controls were then exchanged back to the student. At 1;200 ft; the airplane was turned to base and a second before landing checklist was performed again indicating that the gear was down and locked. At approximately 800 ft; the airplane was turned to final and aligned with the GS. On short final; a third before landing check was performed and flaps were set to 25 degrees. During the flare; the student was wallowing slightly so I had my hands lightly on the controls to dampen the oscillations and was looking outside the aircraft at the runway. The airplane touched down on the touchdown markers on what felt like the landing gear. Within approximately 2 seconds; the airplane collapsed onto its belly and slid to a stop in about 150 ft and 5 ft left of the centerline. All switches were turned off and the aircraft was vacated as quickly as possible. Upon reaching a safe distance; I called the tower on my cell phone to inform them that we were unharmed and that there was landing gear failure. Within 5 minutes; the fire department had arrived; verified that myself and the 2 students were uninjured; and that there was no fire hazard. I also notified my chief and assistant chief pilot who notified the FAA which gave them clearance to recover and secure aircraft in a hangar until it could be inspected by the FAA. I was informed that subsequent inspection by mechanical staff and the FAA has showed that no substantial damage occurred to the aircraft. Interviews of the student flying and the student in the right rear seat both indicated that they saw 3 green lights and no unsafe gear warnings. 2 calls were made to the tower; the tapes were reviewed and no gear warning horns can be heard in the background.

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Original NASA ASRS Text

Title: Despite multiple verifications of three green gear safe lights; the landing gear of a PA44 collapses upon touchdown.

Narrative: A single engine VOR/DME approach was being flown with the left engine at 11 inches of manifold pressure to simulate zero thrust. Upon reaching the FAF; the landing gear was extended and verified down and locked with no unsafe indications. The approach was continued to 1;300 FT; at which time I took the controls from the student so that he could remove his view limiting device. The controls were then exchanged back to the student. At 1;200 FT; the airplane was turned to base and a second Before Landing checklist was performed again indicating that the gear was down and locked. At approximately 800 FT; the airplane was turned to final and aligned with the GS. On short final; a third before landing check was performed and flaps were set to 25 degrees. During the flare; the student was wallowing slightly so I had my hands lightly on the controls to dampen the oscillations and was looking outside the aircraft at the runway. The airplane touched down on the touchdown markers on what felt like the landing gear. Within approximately 2 seconds; the airplane collapsed onto its belly and slid to a stop in about 150 FT and 5 FT left of the centerline. All switches were turned off and the aircraft was vacated as quickly as possible. Upon reaching a safe distance; I called the Tower on my cell phone to inform them that we were unharmed and that there was landing gear failure. Within 5 minutes; the Fire Department had arrived; verified that myself and the 2 students were uninjured; and that there was no fire hazard. I also notified my Chief and Assistant Chief Pilot who notified the FAA which gave them clearance to recover and secure aircraft in a hangar until it could be inspected by the FAA. I was informed that subsequent inspection by mechanical staff and the FAA has showed that no substantial damage occurred to the aircraft. Interviews of the student flying and the student in the right rear seat both indicated that they saw 3 green lights and no unsafe gear warnings. 2 calls were made to the Tower; the tapes were reviewed and no gear warning horns can be heard in the background.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.