Narrative:

Shop personnel were of the belief that the special airworthiness certificate would expire coincident with the annual inspection requirement. This would have been at the end of the month (feb/02). However, the experimental airworthiness actually expired on feb/xa/02. This error was not caught until several days later and after a short flight on feb/tue/02. I did not remove the paperwork and look at it prior to the flight. This would have resolved the problem. My mistake was to 'assume' the experimental shop personnel were monitoring the paperwork status. Oversight was discovered by shop personnel. Aircraft put on non flying status. Renewal of the experimental airworthiness certificate is in progress.

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Original NASA ASRS Text

Title: AN EXPERIMENTAL HELI 295 WAS OPERATED FOR 5 DAYS OVER THE EXPERIMENTAL AIRWORTHINESS CERTIFICATE EXPIRATION.

Narrative: SHOP PERSONNEL WERE OF THE BELIEF THAT THE SPECIAL AIRWORTHINESS CERTIFICATE WOULD EXPIRE COINCIDENT WITH THE ANNUAL INSPECTION REQUIREMENT. THIS WOULD HAVE BEEN AT THE END OF THE MONTH (FEB/02). HOWEVER, THE EXPERIMENTAL AIRWORTHINESS ACTUALLY EXPIRED ON FEB/XA/02. THIS ERROR WAS NOT CAUGHT UNTIL SEVERAL DAYS LATER AND AFTER A SHORT FLT ON FEB/TUE/02. I DID NOT REMOVE THE PAPERWORK AND LOOK AT IT PRIOR TO THE FLT. THIS WOULD HAVE RESOLVED THE PROB. MY MISTAKE WAS TO 'ASSUME' THE EXPERIMENTAL SHOP PERSONNEL WERE MONITORING THE PAPERWORK STATUS. OVERSIGHT WAS DISCOVERED BY SHOP PERSONNEL. ACFT PUT ON NON FLYING STATUS. RENEWAL OF THE EXPERIMENTAL AIRWORTHINESS CERTIFICATE IS IN PROGRESS.

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.