Some Variables Affecting Instrument Check Reading
Abstract
As part of extended studies of human factors in aircraft instrument check reading, two studies were conducted in one of which subjects check read panels of simulated instruments, and in the other singly presented numbers ranging in size from two to seven digits. In the first study, panels of four identical simulated indicators, all aligned at the same setting, ware checked for significant deviations from the reference setting. This simulated part of the task of pilot or flight engineer in checking the engine instrument panel of a four-engine airplane. Three panels were compared, each embodying a different common principle of indication. Average time and percent of errors of twenty subjects in detecting significant deviations in setting among four circular dials with rotating pointers were approximately half as great as time and errors in detecting deviations among four direct reading counters or indicators with a scale rotating behind a fixed pointer. In another separate study, numbers varying only in number of digits (from two to seven digits) appeared in the same exposure apparatus as was used above. Time and errors in detecting differences between verbally and visually presented numbers were recorded for twenty subjects. Speed and accuracy increased directly as the number of digits decreased from seven to two digits, indicating that in counter type indication, there is almost a linear increase in time and a similar increase in errors for each addition of a column beyond two columns.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1950
- Accession Number
- ADA800380
Entities
People
- Shirley C. Connell