sonnel and engineers regarding difficulties encountered and the procedural changes which were required in the perfon-nance of the pylon maintenance, and the failure to establish an adequate inspection program to detect maintenance-imposed damage. Although the safety board directed its investigation to American Airlines, the safety board is concerned that these shortcomings were not unique to that carrier. Since two of Continental Airlines DC-10s were found to have been flying with damaged bulkheads, similar shortcomings were also present in its maintenance program.
The safety board is particularly concerned that because of the limitations of the current reporting system the FAA and key engineering and maintenance personnel at American Airlines were not aware that Continental Airlines had damaged two aft bulkhead flanges on two of its DC-10s until after the accident. In December 1978, after it discovered the first damaged bulkhead, Continental apparently conducted a cursory investigation and determined that the damage resulted from a maintenance error. A repair was designed for the bulkhead and was submitted to McDonnell Douglas for stress analysis approval. The repair was approved and performed, and the aircraft returned to service.
On January 5, 1979, Operational Occurrence Report No. 107901 was published by McDonnell Douglas. The publication contained descriptions of several DC-10 occurrences involving various aircraft systems, personnel injury, and the damage inflicted on the Continental Airlines DC-10. The report described the damage to the upper flange of the Continental aircraft and indicated that it occurred during maintenance procedures used at the time it was damaged. However, the way in which the damage was inflicted was not mentioned. The manufacturer had no authority to investigate air carrier maintenance practices and, therefore, accepted the carrier's evaluation of how the flange was damaged. Since the damage was inflicted during maintenance, 14 CFR 21.3 relieved McDonnell Douglas of any responsibility to report the mishap to the FAA. Although American Airlines was on the distribution list for Operational Occurrence Reports, testimony disclosed that the maintenance and engineering personnel responsible for the pylon maintenance were not aware of the report.