The UK Civil Aviation Authority hopes to introduce a new computer-based assessment of colour vision deficiencies for potential pilots by the end of 2007, which is set to become the international standard.

The authority says it is "concerned" that the present colour vision requirements may be inappropriate for pilot tasks that have emerged since current tests were introduced. It is working with City University in London to develop a computer-based colour assessment and diagnosis (CAD) test that aims to be "fair and task-related", says CAA optometrist Adrian Chorley.

"If we can decide on the most difficult safety-critical tasks we can set a standard for the minimum necessary colour vision requirements in aviation", says Chorley.

The most colour-critical task found so far concerns the precision approach path indicator (PAPI), which uses red and white lights to guide the pilot on the correct runway approach angle, but there are others, mainly outside the cockpit, he adds.

Color blind test W445
 Traditional colour vision tests use spots on cards, such as this one (in which colour blind-individuals see only the yellow square and colour-normal people should see the yellow square and a faint brown circle). The UK CAA proposes using sophisticated computer tests for pilots, that could become the international norm.

In 2005 a CAA-sponsored study by Qinetiq looked at commercial flightcrews' use of colour and its importance, including analysis of the Airbus A321 and Boeing 757 cockpits. A number of areas where colour is critical to flightcrew operations were identified, says the CAA. "These were more common on the Airbus than the Boeing."

CAD validation will be completed by March 2007 and European Aviation Safety Agency approval is expected by the end of the year.

CAA research project manager Steve Griffin says: "We're also talking to the US Federal Aviation Administration. We're the lead player in this and we hope the distinct advantages of the CAD system means it will be taken up".

External link:
Test your own colour vision with online tests developed by Rick Saphire

Source: Flight International