Research for Military Aircraft

The Gulf War was an impressive demonstration of air power in action. Coalition air forces seized control of the air in the first hours, then devastated military facilities in Iraq and Iraqi forces in the field -- paving the way for the remarkable 100-hour victory by coalition ground forces. Airpower did not win the war by itself, but it was the foundation for projecting U.S. military power and overcoming numerical disadvantages on the ground. Airpower is likely to play a similar key role in the next major regional conflict. Thus, the U.S. must maintain its superiority in airpower despite rising costs and declining budgets. The issues are complex and controversial, but ignoring issues will not make them go away. This paper discusses policy and concept issues that need debate and examines two broad strategies for dealing with affordability problems.

The relations between Sustaining Engineering (SE) usage, methods of management, and system quality are determined in this research memorandum. Principal components analysis was used to combine multiple measures of effectiveness into a single measure of aircraft quality and multiple program characteristics into a single measure of high-level management. Levels of SE usage were used with these measures to determine the relations, if any.

This paper attempts to clarify the relationships among the following four hypotheses: (1) the number of material failures across intervals of calendar time containing equal accumulated flight hours follows a Poisson distribution; (2) the number of elapsed flight hours between successive independent material failures follows an expotential distribution; (3) the expected number of monthly material failures is exactly proportional to monthly flight hours; and (4) the observed number of monthly material failures is strongly correlated with monthly flight hours.

This study examines the Navy periodic depot maintenance program for aircraft. It includes evidence that Navy aircraft are inducted for periodic depot level maintenance (PDLM) too often and that too many maintenance man-hours are expended when they are given PDLM. The rework man-hours being expended at depot are not directly related to operational factors but rather to the fact that maintenance managers have strong incentives to err on the side of safety by doing more maintenance and doing it more often than is needed. An alternatiave PDLM program based on decision logic and reliability is offered which corrects this situation and allows a continuous appraisal of PDLM interval and work content. Before such a system can be adopted by the Navy, more component reliability data than are now available will be required. While the requisite data are being gathered, basing intervals on flying hours and continuing the Navy's Aircraft Condition Evaluation program offer improvements in determining depot maintenance requirements. Minimization of risk is achieved by reliability sampling techniques.