Serving Midwest Aviation Since 1960

Oh Say Can You See: Flying with Color Blindness

If you have ever landed at a Class Bravo airport, you know that

the runway looks like the Las Vegas Strip. The strobing glide path, PAPI, illuminated runway centerline, side and center line taxi

way markers all combine to make a colorful and critically important display.

Likewise, if you’ve ever had to navigate into or out of an airport by tower signal gun, you realize how important it is to correctly interpret the controller’s signals.

The FAA also thinks it’s darn important to be able to tell red from green and routinely has us test for color blindness with each flight physical.

Unfortunately, color blindness or color vision deficiency is very common. More than 3 million cases are diagnosed each year in the United States. The most frequently seen is Red-Green Color Blindness which comes in three sub-categories.

The first, deuteranomaly, makes green look more red. This type is usually mild. Protanomaly makes red look more green and less bright. This also is usually a mild distortion of color perception. A combination of

deuteranomaly and protanomaly make you unable to tell the difference between red and green at all. That spells trouble! Blue-yellow color blindness is less common. It makes it hard to tell the difference between blue and green and between yellow and red.

Finally, there’s complete color blindness where you can’t see any colors at all. This is a very uncommon condition.

So how do you know if you have color blindness? The more severe forms, such as complete color blindness or combination red-green color blindness are usually pretty obvious and picked up early in life.

Other more subtle forms of color blindness are often detected in an eye exam such as a pilot receives in a flight physical. That’s the part of the test where you are asked to read the numbers in the

circles with all the colored dots.

Those funny circles are called Ishihara Plates and are a quite sensitive measure of color blindness. If you cannot read all of the six plates correctly, you fail the test.

At that point, a pilot has a decision to make. If you accept the results of this sensitive screening test you can still get a medical certificate but it will have the limitation “NOT VALID FOR NIGHT FLYING OR BY COLOR SIGNAL CONTROL.”

Now if you’re hoping to be a commercial pilot, that’s a mighty big restriction. So, you do have the option of submitting the results of an alternative color vision test performed by an eye specialist.

As I said, the screening test is very sensitive and a lot of guys with mild red-green color blindness can pass acceptable less-sensitive tests such as the Farnsworth Lantern or the OPTEC 900 Color Vision Tester.

Problem is that these gizmos are not widely available so you might have to do some digging on the internet. There are several alternate but more stringent testing machines the FAA accepts. Check with your AME.

Assuming you pass an alternate color vision test, you can submit this to the FAA and if they are happy with it, they will issue a new medical certificate without the color vision restriction.

The FAA has recently changed their policy on alternate testing. Previously, if you could pass an alternate test, you were issued a Letter of Evidence (LOE) by the FAA stating it’s OK to issue a medical certificate without color restrictions even if you couldn’t pass the Ishihara Plates. That LOE was good forever.

Now, the FAA says if you can’t pass the AME’s screening test, you have to repeat and successfully pass an alternate test each time you reapply for a medical certificate.

If you cannot pass any of the alternate color vision tests you still have an option. You can apply for an Operational Color Vision Test (OCVT) to be conducted by the Flight Standards District Office (FSDO). There is a catch, however. You are only permitted to take the test once. If you fail during the day, you can request a night test. If you fail that you are forever restricted to day flying. Furthermore, if you want a Second or First Class Medical Certificate you additionally have to take and pass a Medical Flight Test (MFT). Again, only one try is allowed. On the bright side, the FAA will issue a Letter of Evidence if you successfully get through your OCVT or OCVT and MFT so you won’t have to repeat them. Fly wisely. See you next month.

As always, comments, questions and suggestions are welcome: jdlakinmd@gmail.com. Also, we’ve moved our office to Airlake Airport’s FBO (KLVN)! Call 952-469-4414 or email hannah@wpflights.com for a flight physical appointment.

 

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