Narrative:

While vacuuming the cabin of the aircraft one day prior to the incident, I inadvertently knocked the gear selector switch in the up position. I missed this on the preflight (was not on the checklist). On takeoff when the aircraft got light the gear began it's transition to the up position. The aircraft then settled back to the runway with no gear. The aircraft slid and came to rest approximately 2500 ft from the departure end of the runway.

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Original NASA ASRS Text

Title: SMA ACFT LNDG GEAR COLLAPSED DURING TKOF ROLL DUE TO THE LNDG GEAR SWITCH BEING LEFT IN THE UP POS.

Narrative: WHILE VACUUMING THE CABIN OF THE ACFT ONE DAY PRIOR TO THE INCIDENT, I INADVERTENTLY KNOCKED THE GEAR SELECTOR SWITCH IN THE UP POS. I MISSED THIS ON THE PREFLT (WAS NOT ON THE CHKLIST). ON TKOF WHEN THE ACFT GOT LIGHT THE GEAR BEGAN IT'S TRANSITION TO THE UP POS. THE ACFT THEN SETTLED BACK TO THE RWY WITH NO GEAR. THE ACFT SLID AND CAME TO REST APPROX 2500 FT FROM THE DEP END OF THE RWY.

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.