Narrative:

After touchdown and during rollout, the landing gear collapsed. Landing gear position lights were green when checked on short final. When aircraft was lifted off the runway, the 3 gears dropped down. Cause is still unknown.

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Original NASA ASRS Text

Title: A COMMERCIAL RATED PLT FLYING A C402 WITH CARGO AT CHS RPTS LNDG GEAR FAILURE AFTER TOUCHDOWN.

Narrative: AFTER TOUCHDOWN AND DURING ROLLOUT, THE LNDG GEAR COLLAPSED. LNDG GEAR POS LIGHTS WERE GREEN WHEN CHKED ON SHORT FINAL. WHEN ACFT WAS LIFTED OFF THE RWY, THE 3 GEARS DROPPED DOWN. CAUSE IS STILL UNKNOWN.

Data retrieved from NASA's ASRS site as of July 2007 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.