CAA Paper 2006/04 Part 1: Minimum Colour Vision Requirements for Flight Crew: The Use of Colour Signals and the Assessment of Colour Vision Requirements in Aviation
I haven't read this yet - just downloaded it so far (I'm a bout to go to work)
Go here:
http://www.caa.co.uk/application.asp...detail&id=2407
This paper details an examination as to whether the current colour vision tests and standards for professional pilots are still appropriate for modern aviation. This is part of a study to develop a new colour vision test and establish standard norms for the chromatic sensitivity that can be used to quantify the severity of colour vision lots.
I hope it's good news...