Narrative:

The progressive inspection program is divided into 4 separate operations. 1 operation (inspection) is accomplished every 100 hours of aircraft operation. Additional special inspection requirement are prescribed at other intervals. The program states, 'additional special inspection requirements will be accomplished at their prescribed intervals/intervals coinciding with operations 1-4.' during the period in 6/90, an in-house audit of main and inspection records of the fleet revealed that 800 hour/1 yr special inspections had not been accomplished within the prescribed 1 yr period, although the 800 hour limitation had not been exceeded. Apparently maintenance personnel interpreted the above-quoted excerpt from the progressive inspection program in a manner that allowed them to accomplish the special inspection coinciding with the next scheduled operation, which in this case was to the operation #2. It is believe that this interpretation may be in error inasmuch as the apparent intent of the progressive inspection program is to ensure that the aircraft is completely inspected within each 12 calendar month period, regardless of aircraft hours. All maintenance personnel have been advised of the correct interpretation of the progressive inspection program so as to assure that incidents of this nature will not repeat themselves. Additionally, maintenance personnel have been instructed to adhere to due dates prescribed by the aircraft manufacturer's computerized maintenance tracking system. All items discovered were complied with prior to further flight. It has been determined that the apparent erroneous interpretation of the inspection program and the failure to comply with the special inspection intervals were the result of inadvertence and were not deliberate.

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Original NASA ASRS Text

Title: MISINTERP OF SCHEDULED MAINTENANCE REQUIREMENTS CREATE AN ILLEGAL SITUATION FOR AN ATX CORP.

Narrative: THE PROGRESSIVE INSPECTION PROGRAM IS DIVIDED INTO 4 SEPARATE OPS. 1 OPERATION (INSPECTION) IS ACCOMPLISHED EVERY 100 HRS OF ACFT OPERATION. ADDITIONAL SPECIAL INSPECTION REQUIREMENT ARE PRESCRIBED AT OTHER INTERVALS. THE PROGRAM STATES, 'ADDITIONAL SPECIAL INSPECTION REQUIREMENTS WILL BE ACCOMPLISHED AT THEIR PRESCRIBED INTERVALS/INTERVALS COINCIDING WITH OPS 1-4.' DURING THE PERIOD IN 6/90, AN IN-HOUSE AUDIT OF MAIN AND INSPECTION RECORDS OF THE FLEET REVEALED THAT 800 HR/1 YR SPECIAL INSPECTIONS HAD NOT BEEN ACCOMPLISHED WITHIN THE PRESCRIBED 1 YR PERIOD, ALTHOUGH THE 800 HR LIMITATION HAD NOT BEEN EXCEEDED. APPARENTLY MAINT PERSONNEL INTERPRETED THE ABOVE-QUOTED EXCERPT FROM THE PROGRESSIVE INSPECTION PROGRAM IN A MANNER THAT ALLOWED THEM TO ACCOMPLISH THE SPECIAL INSPECTION COINCIDING WITH THE NEXT SCHEDULED OPERATION, WHICH IN THIS CASE WAS TO THE OPERATION #2. IT IS BELIEVE THAT THIS INTERP MAY BE IN ERROR INASMUCH AS THE APPARENT INTENT OF THE PROGRESSIVE INSPECTION PROGRAM IS TO ENSURE THAT THE ACFT IS COMPLETELY INSPECTED WITHIN EACH 12 CALENDAR MONTH PERIOD, REGARDLESS OF ACFT HRS. ALL MAINT PERSONNEL HAVE BEEN ADVISED OF THE CORRECT INTERP OF THE PROGRESSIVE INSPECTION PROGRAM SO AS TO ASSURE THAT INCIDENTS OF THIS NATURE WILL NOT REPEAT THEMSELVES. ADDITIONALLY, MAINT PERSONNEL HAVE BEEN INSTRUCTED TO ADHERE TO DUE DATES PRESCRIBED BY THE ACFT MANUFACTURER'S COMPUTERIZED MAINT TRACKING SYS. ALL ITEMS DISCOVERED WERE COMPLIED WITH PRIOR TO FURTHER FLT. IT HAS BEEN DETERMINED THAT THE APPARENT ERRONEOUS INTERP OF THE INSPECTION PROGRAM AND THE FAILURE TO COMPLY WITH THE SPECIAL INSPECTION INTERVALS WERE THE RESULT OF INADVERTENCE AND WERE NOT DELIBERATE.

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.