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Collective Colour Vision Thread 4

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Collective Colour Vision Thread 4

Old 24th Apr 2014, 16:20
  #321 (permalink)  
Join Date: May 2012
Location: London, UK
Age: 36
Posts: 34

Rob, he CAD is a waste of time and money. and don't forget to join cvdpa and cvdpilots. Pvt me if you want to know more about the Ishihara plates. good luck

Last edited by pponte; 7th Jun 2014 at 09:56.
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Old 5th May 2014, 16:23
  #322 (permalink)  
Join Date: Aug 2007
Location: UK
Posts: 207

How many plates CAN you read, and under the proper lighting!!

second it is not advisable to 'learn' the plates, the plates are presented to you in a random order to prevent this, if the AME feels that there is cheating going on, its not going to achieve anything!!

the cad test on utube is a sample of the actual test, but its best to try at either city, or glasgow caledonian eye clinic, as they can also offer the holmes wright lantern as well, and that test is still valid providing you follow the CAA protocals for it.

believe me, ive been there, i score a pass to the test standards but not to the CAA standard, and didn't pass the cad test as it went on far to long, they are supposed to use the fast screening cad to start with, and the long version test deeper into the red/green area that was found to the weak!! feel free to PM me.
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Old 8th May 2014, 12:24
  #323 (permalink)  
Join Date: May 2014
Location: Iraq
Age: 26
Posts: 2
Can I be a pilot if I have a color deficiency ?

Hi there ,

I'm mustafa 21 years old from iraq , I have complete my hight school of studies three years ago and looking for my dream till now
My dream is to become a commercial pilot but as you read above , there is a problem that I couldn't pass Ishihara test while I really could recognize the colors as well as the red , green and white , it's clear for me

And really I couldn't left this dream even there were more obstructions I have already faced but really there were something inside made me keep going to achieve my aim ,,

So, guys I'm asking you kindly to guide me on the right way and the right place
And I just want to know how could be the procedures right there in order to get the medical class 1 and start studying ( In U.S. or UK or even in EUROPE )

Last thing if there is something to do , how will be my chance at the future employments in this case ?

I hope I will get the right answer from you guys
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Old 9th May 2014, 08:49
  #324 (permalink)  
Join Date: May 2012
Location: London, UK
Age: 36
Posts: 34
Message edited:
second it is not advisable to 'learn' the plates, the plates are presented to you in a random order to prevent this, if the AME feels that there is cheating going on, its not going to achieve anything!!
Rob and The presence pilot:

pvt me and I'll give you more details

The presence pilot, the states have some exams which are very easy to pass, compared to the normal ishihara. Try the keystoneview for example, they've got 6 compatible ishihara plates, if you pass then it's a go, no need to be tested with 24 or the 38 series! Also Canada used to have an easier exam to pass (the Farnsworth D15 - not a lantern)


Last edited by pponte; 7th Jun 2014 at 09:58. Reason: No more free advertising
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Old 9th May 2014, 12:32
  #325 (permalink)  
Join Date: Oct 2013
Location: Brazil
Age: 23
Posts: 2
Hello guys.
I have a question about the FAA CVD standards.

Ishihara pseudoisochromatic plates: Concise 14-plate edition: six or more errors on plates 1-11; the 24-plate edition: seven or more errors on plates 1-15; the 38-plate edition: nine or more errors on plates 1-21.

Do they really follow those procedures? Will I be considered color vision safe if I fail 5 plates(official 14 plates test) or the doctor can disqualify me even with this score ?
I'm asking this question because I read cases of pilots in the US that weren't tested with the official Ishihara plates but with a shorter version with just 8 or 9 plates and no errors were allowed.
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Old 10th May 2014, 09:53
  #326 (permalink)  
Join Date: May 2012
Location: London, UK
Age: 36
Posts: 34

each exam has different criteria, therefore the ones that use 6 plates will allow less errors. by the way; the plates are not exactly the same as ishihara.

Last edited by Bad medicine; 10th May 2014 at 18:41. Reason: No more unpaid advertising - 40 free mentions in this thread already
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Old 27th May 2014, 12:08
  #327 (permalink)  
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Posts: 272
You will get positive changes in Europe if it is tackled in the right way but it needs good coordination.

Australia got rid of 95% of its colour vision regulations thanks to Dr. Arthur Pape in 1989 who proved that deutans (the majority of cvds) are Colour Safe and able to fly perfectly safely - and we have enjoyed the results, with CASA being forced to accept us, for 25 years.

The last remaining restrictions currently hold back a protan cvd DASH 8 first officer (CPL only required for first officer and does not have to pass any colour test) from becoming captain (ATPL required). Protans were left out of the ruling 25 years ago. However his flying record is impeccable with 6000 hours by day and night and written recommendations by all his flight checking captains and simulator check captains.

The court case is set for July 2014. He has a crack set of lawyers and full support from Arthur Pape. If he wins it (and the odds are in his favour) it will have to apply to all protans and thus ALL the regulations are removed in Australia. What a precedent that would be for European courts to consider when combined with 25 years of incident free flying in Australia by thousands of CVD pilots from private to airline level (including cvd captains currently flying their 74Xs and A3XX into your major cities).

See CASA facing questions in the Australian Senate from our Senator Fawcett (ex-army test pilot) prior to the pending court case on the CVDPA Facebook page. Who do you think are going to win https://www.facebook.com/ColourVisio...otsAssociation

This is your fight whether you are living in Australia or Europe! Support them with all your might and passion because you will need this help in your country in short time!

Last edited by outofwhack; 27th May 2014 at 12:43.
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Old 27th May 2014, 14:36
  #328 (permalink)  
Join Date: Oct 2006
Location: Brisbane
Posts: 105
Senator Fawcett's questioning of CASA including our Principal Medical Officer is below. Like outofwhack says, this case will have resounding effects around the globe. Get behind CVDPA and support it!

Thanks Senator for your passionate advocacy of CVD pilots. It's a shame the authorities don't have as much common sense as him.

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Old 28th May 2014, 01:37
  #329 (permalink)  
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Posts: 272
Aviation authorities may reject the Australian facts but a court would not.

Courts act strongly on cases of unjustified discrimination.

Talking is not going to achieve anything. Send some cash to the CVDPA, relax and enjoy the show!
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Old 2nd Jun 2014, 09:21
  #330 (permalink)  
Join Date: Sep 2012
Location: UK
Posts: 24
Stuck with a Class 1 Restricted

I was at the CAA the other week and finally received the news I was dreading, I failed the CAD test which puts to bed the dream of flying commercially. To be fair I already prepared myself for the bad news so I wasn't too bummed out when they said I'd failed, but I always held onto a glimmer of hope I would pass fine.

So now I'm stuck with a restricted class 1 which is now just a glorified class 2, what use is that!

I was wondering if anyone has found themselves in the same situation and what they've done next?
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Old 3rd Jun 2014, 00:07
  #331 (permalink)  
Join Date: Dec 2013
Location: Aberdeenshire
Age: 29
Posts: 36
I also have a Class 1 with that annoying 4 letter NCAT stamped on it! It's frustrating to say the least.

I've been considering on asking a friend of mine who has studied law and is now practising at solicitors firm to draft me up a letter. It wouldn't be a, "I'll see you in court" letter but instead just one asking for concrete evidence on why colour deficiency plays such a negative role in getting a night rating. I'd also put on the letter that I'd be willing to sit in an approved CAA flight simulator and prove that there's absolutely no problem in distinguishing lights both inside and outside the flight deck during the hours of darkness.

I want to expand on my PPL and ICAO need to understand that CVD pilots in no way jeopardise the safety of commercial flight.
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Old 5th Jun 2014, 12:01
  #332 (permalink)  
Join Date: Aug 2008
Location: Za farzer land
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Guys, I am a Captain with an airline flying jets in the Southern Hemisphere. I have many thousands of hours flight experience and have been flying now for over twenty years. I have not once experienced issues with colour deficiency in my professional aviation career.

I have sat the CAD test and have failed. Previous to this I have sat many colour vision tests, some I have passed and some I have failed. The tests I have consistently passed with 100% pass rate are any practical environmental test. I have passed PAPI test, tower gun tests and a pratical flight test during day and at night, I do not pass the CAD however.

As I have said, I have sat the CAD test and have failed. The CAD test has zero relevance to a pilots environment. For one, it's a synthetic light test done in a synthetic environment asking the applicant to to distinguish rapidly moving coloured targets in the dark after your eyes have had time to adjust. Please explain where in aviation would you ever have to distinguish multiple coloured lights moving rapidly in a controlled synthetic environment? But hey, I'm just a mere professional pilot with no idea about colour and aviation, I should leave that to the non colour deficient, non professional pilots that designed this test.

The CAD test is only good for distinguishing if the applicant is in fact colour deficient, that's all.

As a professional aviator we use an assortment of visual cues to establish whether we are safely "on approach". In the modern day cockpit we have many tools at hand, not just the PAPI lights. We must utilise all the tools at hand to safely fly an approach. On CAT2 and CAT 3B approaches you do not even use the PAPI as guidance. We certainly don't confuse ourselves with rapidly moving lights.

As professional pilots we adjust to our environment, much like colour deficient drivers having to distinguish traffic lights. You might see the lights as a slightly deferent colour, but your brain learns to adapt to your environment of which we work, day in, day out.

Military pilots have been navigating safely on night vision goggles for many years now without incidence. Night vision goggles do not display colour.

I have contributed to the legal challenge in Australia and suggest anyone who is pursuing a professional pilots career in the future should do the same. Google CVDPA.

Last edited by Fruet Mich; 6th Jun 2014 at 21:43.
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Old 5th Jun 2014, 12:31
  #333 (permalink)  
Join Date: Sep 2012
Location: UK
Posts: 24
Good to hear you are able to fly Fruet Mich but the likelihood of any changes happening within the next 10 years in Europe are slime I believe. Even with the good work the CVDPA are doing any type of change in EASA/CAA regulation will take years to go through. One thing I don't understand is how the CAA can get away with using the CAD test as a valid vision test even though it doesn't list it as a valid means on compliance.

AMC1 MED B.075 Colour vision
(a) At revalidation, colour vision should be tested on clinical indication.
(b) The Ishihara test (24 plate version) is considered passed if the first 15 plates, presented
in a random order, are identified without error.
(c) Those failing the Ishihara test should be examined either by:
(1) anomaloscopy (Nagel or equivalent). This test is considered passed if the colour
match is trichromatic and the matching range is 4 scale units or less; or by
(2) lantern testing with a Spectrolux, Beynes or Holmes-Wright lantern. This test is
considered passed if the applicant passes without error a test with accepted

Hopefully one day all CD pilots are able to fulfill their dreams of flying commercially all over the world hassle free however I fear that day will be too late for me.
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Old 6th Jun 2014, 23:34
  #334 (permalink)  
Join Date: Dec 2013
Location: Aberdeenshire
Age: 29
Posts: 36
I don't think we'll have to wait that much longer to be honest. ICAO know that the way they are testing CVD pilots is wrong and in fact doesn't prove that we're unsafe to fly IFR. I think what the Austrailians have got going is good and if that's successful other aviation organisations will have to follow in their footsteps.
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Old 7th Jun 2014, 05:01
  #335 (permalink)  
Join Date: Oct 2006
Location: Brisbane
Posts: 105
Colour Vision Deficient Pilots See Red

A great article from Paul Phelan from Pro Aviation on this week's saga down under...

Colour vision deficient pilots see red

While the topic of aberrant regulatory conduct dominates the nation’s aviation dialogue, we’re wondering whether a letter from CASA to all employers of pilots might represent a practical joke, an early example of a scorched earth strategy, or an act of rebellion against the ASRR’s erudite recommendations.

We’d speculate that such a bizarre missive could hardly have originated from the aviation medics, who would be well aware that when you want to quote medical research convincingly in support of a position, you need to provide a reference to the relevant original medical research papers that present the evidence referred to. (We’ve requested that reference from CASA and are still awaiting a response.)

It also seems unlikely that the letter got the nod from CASA’s legal office, because it seems to be asking AOC holders and/or pilots to make decisions which CASA’s not prepared to make itself.

No, it’s signed by the executive in charge of CASA’s” Permissions Centre,” sometimes referred to by disenchanted permission seekers as the “Sheltered Workshop.” But what on earth it hopes to achieve is difficult to discern. It tells employers that “the possibility exists that your pilot’s CVD may be of a type and/or severity that could adversely affect aviation safety to a degree greater than was believed to be the case when the medical certificates were issued,” and then it goes on to tell their employers to make decisions they are not equipped to make because CASA simply hasn’t told them what the hell it’s on about and it doesn’t tell them what the problem is and what it considers is an “appropriate” course to take.

Here’s the letter which all AOC holders received on June 5. We follow it with a commentary by Dr Arthur Pape, who is widely acknowledged as Australia’s leading expert on the issue of colour vision deficiency (CVD).
If you’re bewildered by the letter, you’ll find Dr Pape’s analysis enlightening by comparison, and indicative of a clear way forward for any responsible medical official seeking to develop intelligent and effective policies on this not-so-complex issue.

5 June 2014

Dear AOC holder,

Colour Vision Deficiency

I am writing to inform you of actions the Civil Aviation Safety Authority (CASA) has taken in relation to pilots with a recognised colour vision deficiency (CVD) in the light of recent medical research involving the assessment of CVD, and the possible implications of these developments for affected pilots and the operators who employ them.

A number of pilots have taken their medical certificates issued subject to a limiting condition because they do not meet the applicable medical standard for colour perception specified in the Civil Aviation Safety Regulations 1998 (CASR). You may employ one or more pilots whose medical certificates are subject to such a condition.

Recent medical research indicates that the safety-related implications of an individual’s CVD may be more significant than they were initially considered to be, and the possibility exists that your pilots CVD may be of a type and/or severity that could adversely affect aviation safety to a degree greater than was believed to be the case when the medical certificates were issued. CASA is reviewing the situation and will consider what further action, if any, may need to be taken on the basis of that review, at which time affected medical certificate holders will be notified accordingly.

In the meantime, CASA has written to all potentially affected pilots advising them to consider whether it is safe for them to continue to exercise their flight crew privileges subject only to the existing CVD-related condition, and encouraging them to seek the advice of their personal physician or designated aviation medical examiner about any adjustments that should be made to their flying practices, pending the outcome of CASA’s review.

As I told recipients of that advice I would be doing, I write to you now, as the holder of an air operator’s certificate (AOC) who may employ one or more affected pilots, to encourage you to consider whether it is safe to allow those pilots to continue to exercise flight crew privileges under your AOC, subject only to the existing condition, and what adjustments to those arrangements you may consider to be appropriate, in the interests of safety, pending CASA’s further determination of the matter.

For more information visit CASA’s website at:

For further details, please contact Dr Pooshan Navathe principal medical officer, on 131757. Yours sincerely,

Peter Fereday
Executive Manager, Industry Permissions

Enlightenment from Dr Arthur Pape

The Aviation Colour Perception Standard (ACPS), as specified by ICAO and replicated by practically all signatory states, requires that: “The applicant shall be required to demonstrate the ability to perceive readily those colours the perception of which is necessary for the safe performance of duties.

At its philosophical/scientific core, this so-called “standard” represents a conclusion (or argument) based on three implicit assumptions, as follows:

Assumption 1
There is extensive use of colour-coded information in the aviation environment.

Assumption 2
The “safe performance of duties” in the aviation environment is dependent on “the ability to perceive readily those colours necessary etc etc……..”.

Assumption 3
Without ‘the ability to perceive readily those colours, the perception of which is necessary for the safe performance of duties”, these duties will be performed unsafely.

The validity or “truth” of the ACPS relies entirely on the validity or “truth” of each of the three assumptions. In turn, the validity or “truth” of each of the assumptions relies on evidence, as opposed to opinion and/or established prejudice.

Let’s consider the first assumption. At the dawn of aviation, over a hundred years ago, colour coding was used solely in the form of signalling by means of coloured flags or lights, as the means of communication between people on the ground and in the air. It was suggested that people who could not readily perceive the colours of those signals might perform their duties “unsafely”, and that suggestion, under the circumstances of the day, would have had some merit. Out of this there arose the ACPS, whose wording has changed little from those heady days of cloth covered aeroplanes and simple instructions to pilots using simple coloured objects in a simple “code”.

Since then there has been an exponential increase in the use of colour throughout the aviation environment, both in the aviation physical environment and in and on aeroplanes. The list of uses of colour is enormous, and the validity of the first assumption is self-evident to anyone with even a minimal knowledge of the aviation environment.

Result: Assumption 1 is “True”.

Assumption 2 is, however, problematic. For this assumption to be valid, it needs to be demonstrated that the perception of the colour(s) is sufficient and necessary to see the information that is required for the “safe performance of duties”. In other words, “see the colour” equals “see the information”, which results in “safe performance of duties”. This assumption could be tested empirically, but this type of work has never been done in respect to the aviation environment.

Result: Assumption 2 remains an unproven assumption

To paraphrase assumption 3, would go like this: “see no (or different) colour” equals “see no (or wrong) information” which results in “unsafe performance”. To digress briefly, let me state that the existence of individuals with colour vision deficiencies (CVD) is a proven reality. That 8 to 9 percent of the male population and just less than 1 percent of the female population have one or other of the various types of CVD is beyond any doubt. Further, there are numerous reliable and proven tests available to detect and classify the severity of any particular CVD condition. Let me add also that the CAD test is an excellent test to diagnose and quantify CVD conditions.

So, in short, the ACPS, via the implicit Assumption 3 would predict that people with CVD should perform the duties (involved in flying an aeroplane) unsafely. This proposition could be tested empirically (i.e., by measurement, observation and analysis). No formal empirical testing of assumption 3 has ever been conducted.

Result: Assumption 3 is also problematic.

It is a fact that pilots with CVD have been around for a very long time and in considerable numbers. For almost a century, the FAA has applied a wide variety of colour vision tests and practical tests, whereby tens of thousands of CVD pilots either passed the ACPS or were granted waivers against the standard. Since 1989, a few thousand Australian CVD pilots have enjoyed the freedom to fly at night and many hundreds have achieved successful careers in airline operations. If Assumption 3 were “true” one would expect there to be evidence of “unsafe performance of duties” by these pilots. This should be particularly evident in the incident and accident records kept by the aviation authorities of the USA and Australia. A landmark study in the mid 1970s by two researchers (Dille and Booze) working for the FAA examined the accident records of the large group of CVD pilots with a “waiver” and found not even one accident where the existence of a colour vision defect could have contributed to the cause. Furthermore, the accident rate for this group was no different than that of the general pilot population (accidents per 100,000 hrs of recent experience). Until 2002, the FAA had no record of any accident attributed to CVD, and since 2002 there have been none. The significance of 2002 is that in that year a Fedex B727 crashed while on a PAPI-guided night visual approach, and the CVD status of the flying FO was attributed a causal role in the crash. However, two other crew had normal colour vision and also did not see what the PAPI should have been showing them. The relationship between this crash and the significance of CVD is highly contentious. The ATSB and CASA have admitted they have no record of any accident attributed to CVD.

The Australian experience since the Denison case in 1989 has provided excellent positive evidence against the “truth” of Assumption 3. There are estimated to have been several thousand CVD pilots operating with either no restriction or minimal restriction in the period in question, and a significant number at the highest level of airline operations. I can say with confidence that we have examples of even the most severe kinds of CVD working as captains and FOs on the full range of airline type aircraft. These pilots are surveilled, trained, tested and examined in exactly the same way that pilots with normal colour vision are handled. They pass and keep on meeting all requirements “necessary” for the “safe performance of their duties”, and these assessments are made by duly qualified examiners of airmen, as opposed to aviation medical doctors or optometrists. This is taken by many informed commentators as evidence that Assumption 3 is “false”, and raises the question as to whether the ACPS serves any useful role in modern aviation.

It is abundantly evident that the appeal by John O’Brien [A pilot with CVD] and the unprecedented interrogation of CASA on this topic in the Australian Senate has triggered a tsunami of hysterical and irrational activity within CASA. It is my view that CASA’s actions and the responses by the Director and the Principal Medical Officer to the Senate Estimates Hearings reflect an absurd and indefensible position. Claims of “medical evidence” by both in support of their stance cannot be substantiated because such evidence does not exist.

There is no “rocket science” in any aspect of this saga.

Last edited by brissypilot; 7th Jun 2014 at 11:55.
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Old 18th Jun 2014, 09:22
  #336 (permalink)  
Join Date: Sep 2008
Location: West Sussex
Posts: 319
There is an interesting thread running on another forum about LED aircraft lights not being visible to pilots flying with night vision goggles. Apparently there are quite a few helicopters flying around at night with the whole crew using NVGs.

So it is apparently safe for these military/police pilots to fly at night with devices that give a very restricted monochrome view while it is seemingly unsafe for me to fly at night because of my CVD, despite my better than average 6/4 distance vision. Doh!
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Old 18th Jun 2014, 09:31
  #337 (permalink)  
Join Date: Sep 2008
Location: West Sussex
Posts: 319
I don't think we'll have to wait that much longer to be honest. ICAO know that the way they are testing CVD pilots is wrong and in fact doesn't prove that we're unsafe to fly IFR. I think what the Austrailians have got going is good and if that's successful other aviation organisations will have to follow in their footsteps.
RONTOM, There is nothing to stop you flying IFR in The UK with CVD restrictions on your EASA medical. You do not need a night rating to obtain the IR(r) rating, or indeed the new EIR or competency based IR. You just won't be able to use them at night.
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Old 20th Jun 2014, 15:11
  #338 (permalink)  
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Posts: 272
Today's national TV coverage on our CVD challenge in Australia.

Nb. Hundreds of Cvd pilots who failed Ishihara and Farnsworth passed the tower light signal test [ forced in by Arthur Pape's court win in 1989] and made it to airline captain and have been flying safely for 25 years.
The pilot in this news item failed even the tower test but according to his airline check and training captains he is at no disadvantage compared to a colour normal pilot in being able to safely operate - yet casa denies him use of his ATPL because he has not passed this last colour naming test - a signal light that could not possibly be used in airline operations. If we win this case all colour vision testing will be redundant! Please help the CVDPA support this pilot to create a very useful international precedent! The 10+ days in court starts next month!

Queensland pilot challenges CASA over colour blindness restrictions - ABC News (Australian Broadcasting Corporation)

Last edited by outofwhack; 20th Jun 2014 at 16:00.
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Old 20th Jun 2014, 16:05
  #339 (permalink)  
Join Date: Jan 2014
Location: South Africa
Age: 54
Posts: 16
Limited research done by us in South Africa shows that none of the current tests available (including CAD) reliably differentiate between safe colour deficients and truly unsafe ones. We have found that some colour deficient persons are unreliable in critical colour perception based on testing in full simulator facilities, but there was no correlation with Ishihara, Farnsworth CAD or Signal testing.
The problem will remain: How do we identify the risky vs the safe pilot? Should a colour deficient pilot be tested in a standardised and calibrated simulator by means of a set of set tests. Should this testing be left to the instructor rather than the doctor, or should it be assessed by partnering the instructor and doctor? How many colour related mistakes are made by those with normal colour perception during similar testing?
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Old 20th Jun 2014, 17:06
  #340 (permalink)  
Join Date: Apr 2004
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Posts: 272

If a task does not rely on colour for safe decision making then there is no need to classify as colour safe/unsafe.

Driving and flying do not rely on colour. Colour is used but its redundant. There is no colour testing for drivers because colour deficient drivers are able to make the same safety decisions as colour normal drivers - just like pilots.

In marine navigation there are tasks where colour is the only clue and thus it is sensible to determine if someone is safe and unsafe.
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