Kharon:
There is no reference made to manufacturers MEL for Cathode Ray (CRT) screens, these made for when the colour gun fails and the screens go to monochrome grey scale. It is significant that insofar as Airbus and Boeing are concerned there are no operating restrictions related to the lack of 'colour'. This stands as direct evidence of how much weight manufacturers and certifying authorities place on the 'luxury' of colour display as opposed to symbols and annunciators.
Let's not forget that items such as EFIS displays, reaction times and much more were already covered in enormous detail during the
Denison v CAA case 25 years ago. A quick refresher:
8. ...We understand that there are a considerable number of other pilots with defective colour vision who have requested the granting of licences which do not contain a condition prohibiting their piloting aircraft at night. For that reason the respondent indicated that it wished to conduct this case as a test case. Mr Rose, therefore, informed the Tribunal that the respondent intended to present its case in a manner which would encompass not only the applicant's situation but also broader issues relating generally to defective colour vision. At the request of the respondent the Attorney-General granted legal aid to the applicant to ensure that he was not disadvantaged by the respondent presenting his case in that manner. The matters which we have to consider in these proceedings have consequently been extended well beyond those which the applicant originally sought to raise, that is to say whether his defective colour vision made it unsafe for him personally to pilot an aircraft at night. The proceedings have taken 28 hearing days. In order to reach conclusions on those matters raised it is necessary for us to address a number of questions. Because of the amount of evidence given we cannot set all of it out in detail; however, we have taken the whole of it into account in making our decision and in expressing conclusions on the various matters raised for our consideration.
Remember, the O'Brien case only had 3 hearing days and essentially picked up where Denison left off. There shouldn't have been any need to re-examine all the issues such as EFIS as these were already found to be a non-issue. No doubt this will be re-emphasised in the written submissions.
59. The respondent arranged for the Tribunal to see the reproduction of the cockpit of a Boeing 767 aircraft in a flight simulator and to have the use of the instruments demonstrated to us in simulated flight by Captain J. R. Rhind. Characteristics of modern aircraft instrumentation were described to us by Mr Chatfield. He showed a number of photographic slides which demonstrated the general lack of colour in the cockpits of older aircraft and the increasing use of colour, and the greater sophistication of that use, in more modern aircraft. He said that, although initially the new instrumentation had been used principally in larger passenger transport aircraft, lighter aircraft were now being equipped with sophisticated Electronic Flight Instrument Systems ("EFIS").
61. The research conducted by Professor Cole and Dr Macdonald was designed to ascertain whether the response time taken by a person with defective colour vision to obtain information from EFIS displays was longer than that taken by persons with normal colour vision. In order to carry out that research they took photographs of part of the EFIS instrumentation in a simulator, namely the Horizontal Situation Indicator ("HSI"); different photographs were taken of the HSI as it was at various stages of a simulated flight
I see that CASA have once again trotted Cole out to give evidence this time despite having his research severely discredited in the Denison case:
64. There is one major reason for querying generally whether the research justified any conclusion being drawn in respect of the task of piloting an aircraft. That is that the subjects were not experienced pilots and were shown still photographs not sequentially related to one another. During the flight of an aircraft the pilot is constantly scanning his instruments; he does not suddenly come upon an instrument displaying certain information. He has been seeing that instrument at frequent intervals for however long the flight has lasted. Consequently, whenever he sees it, he does so in the context of the flight. He knows what has gone before and if, as is usual, the flight is being conducted in accordance with a flight plan, what he can reasonably expect to come next. The greater his experience as a pilot using such instrumentation, the greater will be his understanding of its display and consequently his ability to derive from it in the context of the flight the information which he requires in order to fly the aircraft safely.
65. ...In the course of the hearing we heard a considerable amount of evidence about the colour coding of that instrumentation, about the other ways in which it conveys information and also about aural warnings which accompany instrumentation displays indicating equipment malfunctions which may be serious. We also heard a good deal of evidence about the weather radar part of the EFIS.
74. It was suggested to us that, while we might find that no single difficulty which pilots with defective colour vision might encounter in acquiring information from colour-coded displays would result on its own in a significant risk to the safety of air navigation, the combination of several difficulties experienced together would have that result, as it reduced their ability to take appropriate action sufficiently quickly in a situation of emergency. The delay in acquiring any one piece of information and, therefore, in responding to the situation to which it relates might itself be insignificant. But, if a number of pieces of information had to be acquired and responded to at the same time, the total delay might be significant. Having regard to the nature of emergencies which may arise during the flight of an aircraft, we have come to the conclusion that in practical terms the total delay, if any, will itself be insignificant and that the risk to the safety of air navigation will still not be significant or unacceptable.
The above quotes are just a small snapshot of how extensively the tribunal in Denison considered all these sorts of issues and much more (there are actually 15 paragraphs in the decision which discuss EFIS alone).
No doubt the current tribunal will be carefully reading through Denison in the lead up to making a judgement this time around.
Essentially, the only thing that has changed since then is that we now have 25 years of demonstrated safe flying experience by CVD pilots at all levels of the industry who continue to perform no differently to colour normals. There is also of course the backwards thinking soon to be ex-PMO
