Thanks Sunfish.
I remind all that in no way would we suggest that the use of colour in present-day (or for that matter, old-day) cockpit display technology needs any modification to accommodate the CVD pilot. We have data on the most severe CVD types operating completely safely in the most modern of aircraft types (the entire Boeing and Airbus fleet). I stress this to counter the often stated (at aeromedical meetings) unreasonableness of suggestions that the advantages to colour vision normal participants of colour in the cockpit display environment should be diminished to facilitate the use of such displays by CVD individuals.
That said, the same logic doesn't apply to the "most critical" instances of colour usage in the aviation environment external to the aircraft: the PAPI. I refer the reader here to our published paper
http://www.cvdpa.com/images/further_...SAM%202013.pdf
in which we describe the hazards of using colour coding in VASIS displays, as illustrated by the 2002 crash of FedEx Flight 1478 at Tallahassee Florida.
PAPI is a disaster that has without any doubt been implicated in at least one crash, and is likely to be so implicated in future crashes, and next time there won't be a CVD pilot on the flight deck to 'carry the can'. A major source of information in compiling our analysis of the FedEx crash came from a paper by Clark and Gordon, research scientist at the Aeronautical Research Laboratories, Department of Defence, Melbourne, Australia: "The Hazards of Colour Coding in Visual Approach Slope Indicators".
Australian pilots, almost without exception, bemoan the introduction of PAPI to replace the T-VASIS, an approach aid that was essentially 'shape coded' and which had huge SAFETY advantages over the PAPI. The Clark and Gordon conclusions were echoed and amplified by USA research on behalf of the FAA which provided laboratory confirmation of the reversal of red PAPI signals to 'Pink-white'. Clark and Gordon described this phenomenon as "Fail unsafe" and many airline pilots I have interviewed on this topic have confirmed they too have observed the reversal of the signals generated by the PAPI under conditions of low temperatures and high humidity, the presence of thin mist and/or sea spray (often reported in relation to Denpasar, Bali). In the end, PAPI won the competition on the basis of cost and convenience (in maintenance), but SAFETY was the loser. So much for science!