The College of Aeronautics has developed a methodology which can be used to predict R & M targets, during the conceptual design stage. It can predict dispatch reliability for commercial aircraft, defect rates for combat aircraft and maintenance manhours for flying hour for both. In addition, a program has been produced which will predict combat aircraft availability.

These tools have been used in recent years as part of Cranfield aircraft design group projects. These projects are unique in the level of detail and the practicality of the design programmes. This paper will use the S-87 combat aircraft project as an example. The author spent 3 months performing the conceptual design of the aircraft. Information was then given to the 28 MSc students involved in the project. They were given individual responsibi1ity for detail design of structural components, systems, or R & M aspects of the whole aircraft.

The R & M prediction methodology was used to obtain aircraft and system targets. Reliability, Maintainability and vulnerability modelling were then performed and their results fed into the availability model. These results showed the effects of design decisions on the aircraft operations and demonstrated the importance of design for R & M to all of the students.