I'm a UK CAA licensed aircraft engineer. I hold full certifying authority on several airliner types, including limited avionics authority.. .. .I'm currently looking into flying training for myself. However, I know from experience that I will fail both the Ishihara test and the Farnsworth Lantern test.. .. .I have read that one of the reasons cited by aviation authorities for the high colour perception standards currently in force, is the requirement to differentiate between coloured lights on the flight deck.. .. .My point is this-. .. .If my colour perception standard prevents me from operating aircraft at night as a pilot, why does the same aviation authority allow me to carry out high power engine runs, with all the attendant risks of fire, loss of aircraft, etc, at UK airports? I assume the lights I monitor are the same lights pilots use!. .Most transport aircraft have a multitude of lights on their warning panels, red, green and white. Amber and red attention getters on the glare shield inform the pilot to look at the master warning panel. If an amber attention getter flashes, would a pilot ignore it because it isn’t as important as a red attention getter? Of course not, be it red or amber, a pilot would look at the master warning panel. Again, on the master panel, colour vision does not help. There’s dozens of amber lights and almost as many red. You still have to read the legend on the light to find out what system you are supposed to action.. .. .And how about the safety aspect? The EFIS, weather radar and other colour using equipment that prevents you and I from flying, is serviced and certified by me!. .. .Fear not, although I am unable to pass a CAA colour test, I find no problem (as I suspect most of you do) in recognizing all colours in the flight deck, both at night and in daylight (I have confirmed this with other ‘normal’ engineers). I also find no problem in recognizing airfield lights, even PAPIs on my jumpseat rides.. .. .Now, I do of course realise that there is a difference between dealing with an engine fire in flight and on the ground, but I believe colour perception will play a negligible part in flight deck operations.. .. .As a note of interest, the CAA has no colour vision requirement for licensed aircraft engineers.