Narrative:

Heavy vibrations were felt during the landing roll while slowing to 20 mph or less. Thinking the source was the nose wheel; back pressure was applied to the elevator to try to stop vibrations. When doing so had no effect on the vibrations the back pressure was relieved which made the vibrations greater and back pressure was reapplied. At that moment the right main gear folded under the aircraft at a speed of 10 mph or less.

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Original NASA ASRS Text

Title: A private pilot undergoing multi-engine training in his C-310 with an instructor suffered the collapse of the right main gear on landing roll. The instructor believed all immediately prior training landings were well in the 'normal' range; but noted the landing gear had been subject to maintenance on a recent annual inspection.

Narrative: Heavy vibrations were felt during the landing roll while slowing to 20 MPH or less. Thinking the source was the nose wheel; back pressure was applied to the elevator to try to stop vibrations. When doing so had no effect on the vibrations the back pressure was relieved which made the vibrations greater and back pressure was reapplied. At that moment the right main gear folded under the aircraft at a speed of 10 MPH or less.

Data retrieved from NASA's ASRS site as of July 2013 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.