22. Preliminary Design Equations for Aircraft Weight Estimation

Paper

Abstract

If some of the existing experimental designs had been more accurately weight predicted early in the stages of design, a good many serious design mistakes would have been averted, and more accurate prediction of performance would have been possible.
The random methods of weight estimation may be referred to as wishful thinking. The great tendency to underestimate the weight on new aircraft has a duel origin. First of all, the customer wants a very light and very efficient aircraft; secondly, the manufacturer wishes to sell the customer a very light and very efficient aircraft. In spite of good intentions and in spite of continuous efforts of the weight control engineers, the very light aircraft is never built. Due to highly optimistic methods of weight estimation, the weight increases at a certain rate during the process of design and sooner or later it is discovered to everyone’s dismay, that the original estimated weight and center of gravity location are superseded by more menacing figures.
The program of rigid weight economy during the process of detail design can be conducted independently of the original estimated weight. Honest weight estimation would help to avert costly redesigns on production models.