Recommended Army Aviation 40-501 Standards of Medical Fitness on Visual Acuity / Resolution With Respect to Degraded Visual Environment Flight Operations
Abstract
Standards identify specific visual performance expectations that can be minimally achieved under certain conditions. When considering a Degraded Visual Environment (DVE), an aviators minimally-achievable acuity is a highly variable number. This is the result varied individual sensitivity responses to decremented contrast, and to decreased background luminance. Acuity responses under DVE conditions vary on a sliding performance scale as a function of those two influencing variables. Subjectively, the common attitude exists that decreased luminance and decremented contrast have the same magnitude or degree of adverse effect upon visual resolution. If that were a completely accurate contention, the goal of establishing why a modern DVE-based visual resolution standard is necessary would be a cleaner problem to address. Nevertheless, the goal is to establish a recommended visual performance standard such that an aviator is able to meet minimally achievable performance expectations under extremely challenging visual conditions. The current physical examination acuity standard does not make reference to the demands created by varied luminance and contrast effects that can represent DVE conditions. This recommendation of strengthened luminance- and contrast-testing parameters is intent on titrating individual visual performance variability with reference to DVE, such that DVE-based aviation fatalities can be eliminated through identification of those more likely to experience a DVE-based mishap. As this material is reviewed and analyzed, the objective performance requirements will become clearer, as will the recommended visual performance standard, resulting in a much reduced future fatality rate.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 2019
- Accession Number
- AD1077773
Entities
People
- James Q. Truong
- Morris R. Lattimore
- Thomas H. Harding
Organizations
- United States Army Aeromedical Research Lab