In 1967 American Airlines switched from a Time Between Overhaul maintenance program to a Condition Monitored Maintenance program. Under this program, the engine life cycle is fully controlled by monitoring in-service performance and by a B-O-W (Bill-of-Work) control system for each engine on an individualized basis. Engine manufacturer recommended and FAA approved disc life limits prevail. Where experience or regulations indicate a requirement, life or run time limits are imposed on a given part or assembly or engine or special maintenance action. An Engine Working Group (EWG) functions for each engine. The EWG arrives at decisions by agreeing unanimously on modifications and their schedule of incorporation, build standards or the solution of any problem that would prevent the engine from achieving its objectives -- material cost, manhours per build, reliability, fuel consumption. The basic engine gas path parameter trend plots are computer generated, using data recorded by the Flight Engineer and teletyped directly to the computer. The trend plots are reviewed daily by qualified engineers for incipient failures.

  • Corporate Authors:

    Shell Oil Company

    1 Shell Plaza, P.O. Box 2463
    Houston, TX  United States  77001
  • Authors:
    • Wollmershauser, C
  • Publication Date: 1977

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00174310
  • Record Type: Publication
  • Source Agency: Engineering Index
  • Report/Paper Numbers: No. 442
  • Files: TRIS
  • Created Date: Jun 28 1978 12:00AM