Colour Vision Standard in Aviation
by Arthur Pape MD
The colour vision standard in aviation has obstructed the aspirations of thousands of pilots and would-be pilots around the globe. Nowhere more than in Australia has the fight been more aggressively fought to remove restrictions on pilots with reduced (defective) colour vision. The author, an Australian commercial pilot, medical practitioner and colour defective, conducted two major court appeals against the standard in the late eighties, both of which succeeded in removing operational restrictions from colour defective pilots in that country.
Colour defectives have one and one only disability: they cannot accurately and reliably name certain colours when they see them. They fail colour vision tests, specifically designed to detect this disability. Supporters of colour vision standards argue that colour is used ubiquitously in aviation to code important information that pilots need to safely perform their duties as pilots. However, when testing their proposition, these supporters invariably make the naming of colours the end-point of the experimental task. Predictably, colour defectives perform less well than colour normals in this setting.
However when flying aeroplanes the accurate naming of colours is never an end-point in itself. It is the underlying information of operational significance that pilots need to access to make sound and safe operational decisions. A long list is easily drawn up of the many pieces of operationally significant information used by pilots. For example, pilots are intensely interested in navigational information, powerplant and airframe parameters, the occurrence of abnormal flight conditions and adverse weather, and so forth. Only by familiarity with the way in which pilots use this information, how each and every piece thereof translates into operational decision making, can the colour perception standard be properly appraised. It is a big task, and one with which the author has been involved for twenty years.
The extent to which colour plays a significant role in the provision of these many pieces of information is by no means established scientifically. The degree of disadvantage, therefore, that a colour defective pilot might experience is similarly not at all clear. The experience of the many thousands of colour defective pilots now flying with no restriction in the USA and Australia would suggest that there is no disadvantage at all. Likewise, careful analysis of the geometry of collision avoidance at night and of the information available in the state of the art EFIS display systems reveals that, on first principles, colour vision defectives should have no difficulty in performing all the tasks required in the "performance of their duties".
The author recently attended an ICAO working group in Warsaw, Poland, on behalf of IAOPA. At that meeting it was clear the European representatives were intent on increasing the stringency of their already very strict colour perception requirements. The prospect for a rational international standard is therefore slim. What appears will happen is that the USA and Australia, and possibly Canada, will progress to ever less restrictive colour vision standards, while Europe goes in the opposite direction. There is an underlying reason for this: the European states offer far less opportunity to appeal standards such as this one before the law. The standard is vulnerable to detailed examination, an exercise the protectors meticulously avoid.
This editorial as well as the following web page offer insight into the colour perception standard and its weaknesses. Perhaps it may stir some long overdue debate, particularly where the proponents of this standard stand so well shielded from critical scrutiny.
Arthur Pape MD