476. An Approach to the Value of Weight Savings on Military Aircraft

Paper

Abstract

The value of weight savings in a military aircraft is determined by the price of the aircraft, its useful load, and the expected cost of operating it in service.
A military aircraft is justified by the potential effectiveness of its useful load. Useful load is defined as that portion of the total weight which it is desirable to maximize to obtain the greatest mission effectiveness. Saving weight can be considered equivalent to increasing useful load.
The value of weight savings is therefore established by the price the customer must pay for alternative forms of useful load. The nearest substitute for the useful load that may be obtained by saving weight in a military airplane is for useful load that can be purchased by buying one more airplane of the same type.
The value of weight savings is more than the price of the useful load obtained by simply buying one more airplane, because it is not necessary to fly the additional airplane to acquire the same potential capacity. If the additional capacity were utilized by flying as well as buying the additional airplane, however, it would have greater military value than if it were concentrated in fewer aircraft. Therefore, the value of weight savings is less than the total cost – per unit of useful load – of operating an additional airplane over its service life as well as buying it.
These measures are essentially independent of how the effectiveness of the airplane may actually be limited in combat missions: by payload weight, range, endurance, or time on station. The evaluation therefore does not depend upon arbitrary assumptions regarding possible future combat situations.