Pilot Workload - A Practitioner's Problem

Abstract

The selection of a new military or commercial aircraft is based, in part, on life-cycle cost or cost-of-ownership. These parameters include both acquisition and operating costs. In the latter, personnel cost is an increasingly important factor. This leads directly to reduction in crew size and automation or reallocation of tasks previously assigned to the now-missing crewmen. It is also common to find that a new aircraft is more complex than the one it replaced. Frequently then, in new aircraft there are fewer crewmen and at least as many functions to be performed as in older aircraft. The challenge to designers of flight decks and avionics suites is to configure the crew station in such a way that required tasks can be accomplished with the allotted crew complement and workload is held within reasonable limits. The purpose of this paper is to outline the role of the human factors practitioner in meeting this challenge, particularly our role in predicting and measuring workload.

The process of producing a new system can be broken into (a) statement of functional requirements, (b) design and manufacture, and (c) verification that the design, and finally the system, meets the requirements. In practice, these stages are iterated several times from preliminary design to detailed design to prototype and final production.

As good empiricists, we recognize the verification stage to be a test of the hypothesis that the test article meets the requirement. The functional requirements must be stated in quantitative terms and the verification must have all the characteristics of a good experiment.