Narrative:

Upon takeoff from the airport; the main cabin door popped open. At that time I contacted tower in order to return for landing. When I came back to land; the tower advised me that my gear was not down almost in the flare. I immediately applied power and the propellers grazed the runway. I advised tower that I was having trouble with the landing gear switch (my daughter had a video camera and I have undeniable proof that the landing gear switch was down). I circled airport and performed emergency landing gear extension checklist. I then landed at airport without further incident. After returning to ZZZ; I spoke to other pilots who rented this same aircraft and found out that other pilots had trouble with the door popping open.

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Original NASA ASRS Text

Title: PVT PLT RETURNING FOR LNDG DUE TO MAIN CABIN DOOR OPENING EXECUTES A GAR WHEN ALERTED BY THE TWR THAT THE GEAR WAS NOT FULLY EXTENDED. PROP STRIKES ARE THE RESULT.

Narrative: UPON TKOF FROM THE ARPT; THE MAIN CABIN DOOR POPPED OPEN. AT THAT TIME I CONTACTED TWR IN ORDER TO RETURN FOR LNDG. WHEN I CAME BACK TO LAND; THE TWR ADVISED ME THAT MY GEAR WAS NOT DOWN ALMOST IN THE FLARE. I IMMEDIATELY APPLIED PWR AND THE PROPS GRAZED THE RWY. I ADVISED TWR THAT I WAS HAVING TROUBLE WITH THE LNDG GEAR SWITCH (MY DAUGHTER HAD A VIDEO CAMERA AND I HAVE UNDENIABLE PROOF THAT THE LNDG GEAR SWITCH WAS DOWN). I CIRCLED ARPT AND PERFORMED EMER LNDG GEAR EXTENSION CHKLIST. I THEN LANDED AT ARPT WITHOUT FURTHER INCIDENT. AFTER RETURNING TO ZZZ; I SPOKE TO OTHER PLTS WHO RENTED THIS SAME ACFT AND FOUND OUT THAT OTHER PLTS HAD TROUBLE WITH THE DOOR POPPING OPEN.

Data retrieved from NASA's ASRS site as of January 2009 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.