Narrative:

I am a member of a soaring association. We were conducting operations from the threshold end of the grass runway 12 at frederick airport. While taxiing back to the line, on the right side of the runway to pick up another glider to tow aloft, I felt a bump. A second, or so later, the right landing gear collapsed. Upon investigation, it was apparent that I had taxied the aircraft over a manhole cover which was protruding two to four inches above the grade, but uneven, unmarked and blending into its surrounding area and constituting a hazard.

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Original NASA ASRS Text

Title: A PA25 GLIDER TOW PLT, WHILE TAXIING ON THE R SIDE OF RWY 12 AT FDK, ENCOUNTERED A MANHOLE COVER THAT WAS UNMARKED AND ULTIMATELY CAUSED THE R MAIN GEAR TO COLLAPSE.

Narrative: I AM A MEMBER OF A SOARING ASSOCIATION. WE WERE CONDUCTING OPERATIONS FROM THE THRESHOLD END OF THE GRASS RWY 12 AT FREDERICK ARPT. WHILE TAXIING BACK TO THE LINE, ON THE R SIDE OF THE RWY TO PICK UP ANOTHER GLIDER TO TOW ALOFT, I FELT A BUMP. A SECOND, OR SO LATER, THE R LNDG GEAR COLLAPSED. UPON INVESTIGATION, IT WAS APPARENT THAT I HAD TAXIED THE ACFT OVER A MANHOLE COVER WHICH WAS PROTRUDING TWO TO FOUR INCHES ABOVE THE GRADE, BUT UNEVEN, UNMARKED AND BLENDING INTO ITS SURROUNDING AREA AND CONSTITUTING A HAZARD.

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.