Narrative:

I taxied to runway to conduct a training flight. After completing a run-up at the south end of the wide portion of the runway, I back taxied to the end of the narrow portion of runway. I announced all of my intentions on CTAF. The runway was clear of personnel and vehicles. I departed and noted nothing unusual. After a short time I was contacted by company personnel on the ground, who advised me to return to the airfield. I did so immediately. After I landed I was informed by company ground personnel that another pilot told him that during my departure, I had traveled over a plywood 'X' that was marking the runway as closed. Doing so, damaged an antenna on the aircraft's belly. I never saw the 'X' during my departure, nor was I aware that the runway was closed. The airfield I was operating out of is privately owned, therefore, NOTAMS are not available. During this flight, there were no injuries and the aircraft did not receive substantial damage as defined in NTSB 830.

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Original NASA ASRS Text

Title: INST AND STUDENT PLT OF C337 TKOF ON CLOSED RWY AT PVT AIRFIELD IN FLORIDA. TAXIED ACROSS PLYWOOD 'X' AND STRUCK ACFT'S ANTENNA.

Narrative: I TAXIED TO RWY TO CONDUCT A TRAINING FLT. AFTER COMPLETING A RUN-UP AT THE S END OF THE WIDE PORTION OF THE RWY, I BACK TAXIED TO THE END OF THE NARROW PORTION OF RWY. I ANNOUNCED ALL OF MY INTENTIONS ON CTAF. THE RWY WAS CLR OF PERSONNEL AND VEHICLES. I DEPARTED AND NOTED NOTHING UNUSUAL. AFTER A SHORT TIME I WAS CONTACTED BY COMPANY PERSONNEL ON THE GND, WHO ADVISED ME TO RETURN TO THE AIRFIELD. I DID SO IMMEDIATELY. AFTER I LANDED I WAS INFORMED BY COMPANY GND PERSONNEL THAT ANOTHER PLT TOLD HIM THAT DURING MY DEP, I HAD TRAVELED OVER A PLYWOOD 'X' THAT WAS MARKING THE RWY AS CLOSED. DOING SO, DAMAGED AN ANTENNA ON THE ACFT'S BELLY. I NEVER SAW THE 'X' DURING MY DEP, NOR WAS I AWARE THAT THE RWY WAS CLOSED. THE AIRFIELD I WAS OPERATING OUT OF IS PRIVATELY OWNED, THEREFORE, NOTAMS ARE NOT AVAILABLE. DURING THIS FLT, THERE WERE NO INJURIES AND THE ACFT DID NOT RECEIVE SUBSTANTIAL DAMAGE AS DEFINED IN NTSB 830.

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.