Collective Colour Vision Thread 3

[east_sider]

City Uni new PAPI test

After my appointment with City Uni for a full colour vision assessment back in July I volunteered to trial the new PAPI test and have just been back to do the tests today, this is a write up of my experience.

I was given a number of different tests. Three of these were a repeat of the Colour Assesment and Diagnostic test (CAD) described in my post above. It is the computer monitor with grey animated square, and an area of colour moving across one of the diagonals. It runs in 1 second cycles and you press a button corresponding to the corner of the square where you think the coloured area stopped moving. The difference each of the three times I took this test is the amount of background noise added in to the animation. The "standard" level is 45% noise, which I did last time. This time I did 12%, 60% and 90% (I think). Presumably the idea is to see how people perform at more extreme levels of ease/difficulty, to help find or confirm the "normal" noise level to use.

Then took the PAPI test - this is basically a series of four lights in a horizontal line, which can be white or red. They light for about 1 second then you have to say how many red lights you see, from 0-4 (ie five possible answers). Having never used PAPIs (I'm a <10hours PPL student) I found this test easy, but I can seperate red and white ok, its the white/green on the Holmes Wright lantern I struggled with.

There is a second stage to this test with five different colours - white, red, green, yellow and blue. These either appear on their own, or in a pair, one of which is always white. You have to say the other colour. I found blue and red easy every time, struggled to differentiate white, green and yellow sometimes.

The CAD test is important as according to the person testing me, it will likely be used in conjunction with the PAPI test in the future. This is basically because the CAD test is relatively easy to recreate in reasonably equal conditions (its basically just a software package I guess, maybe with a certain type of monitor etc). The PAPI test is a large, fairly mechanical piece of kit which is cumbersome and expensive, so I gathered not practical for widespread use.

It is my understanding that something like this could happen in the future:

1. The CAD test "replaces" Ishihara plates as the initial screening, possibly for Class 2 as well as Class 1. It is more accurate than Ishihara as it narrows your CVD down to a fairly close range.

2. Anyone "failing" this test, against whatever standards/prescription is set, would then have to take the PAPI test. This would probably only be possible at a few or even just one (Gatwick?) location.

Please note this last hypothesis on the future is entirely my understanding from talking to the person testing me, I got the impression it was still a moving piece (so to speak) with the CAA and nothing is definite yet. Clearly the results of the testing phase I took part in will help shape the future.

I hope somehow this all leads to a fairer or more realistic set of standards and tests for colour vision in the future. All I want to do is fly and no one I've spoken to so far can point to specific things that I can't do, apart from perhaps identify an aircraft at night from wing lights only. How likely is that in this day and age? If you're IFR in controlled airspace you'd better know a collision is approaching long before those lights save you.... or they could just change it worldwide to blue and yellow for port and starboard!!!

Probably too much detail on here already but if anyone wants more feel free to PM. I know one or two other people posting on this thread might be taking part in this trial, any comments from others experiences would be very interesting.