VISION FOR THE AVIATION MEDCAL
Who Checks your Vision
The DAME checks Vision at each aviation medical.
In addition, a checkup with an Designated Aviation Optometrist (DAO) is required for class 1 & 3 medical certificates:
- For initial issue
- From 60 years of age: every 2 years
You do not require a visit to a routine visit to a DAO for a class 2 medical.
What are the CASA visual standards for pilots & ATC?
Vsion is check both with correction (glasses or contact lenses) and wthout correction. Remember bring your glasses or contacts if you need them! CASA also require that your vision is tested with your spare lenses.
Class 1 & 3 licenses: 6/9 or better in each eye, and 6/6 when with both eyes
Classs 2 license: 6/12 or etter in each eye, and 6/9 with both eyes.
It makes sense to see an optometrist before your medical if you think you might need glasses.
- Able to read N5 (with correction if needed) close-up whch is defined as a distance of 30cm.
There’s also a test for colour vision & a clinical visual field check for obvious defects.
What happens if I require corrective lenses in order to pass?
Your license will stipulate that you need vsual correction to fly. You will need to carry both your main and your spare lenses with you.
Be prepared for a random ramp-checks that include confirmation that you carrying your lenses with you.
A small-print issue that can occur is that the DAME records the wrong type of lens correction on your medical. A random ramp check can then reveal that your lenses are different from the lenses you sholud be carrying, a situation that is quite stressful.
You therefore need to ensure that the DAME records the correct type of visual correction on the MRS. For example, variable focal, fixed distance or fixed close up.
CASA recently changed the way that applicants are assessed for colour vision deficiency. CASA is following the New Zealand approach in allowing for an ‘operational colour vision assessment’ or OCVA. The assessment comprises a ground-based assessment and an in-flight assessment. Both day flying and night flying are included in the assessments.
Why wear Sunglasses?
Wearing sunglasses is more comfortable but also protects your eyes.
UV increases by 10-20% for every 1,000m increase in altitude. Most aircraft had poor UVA blocking windshields in a study pubished in 2016. Long term exposure to UV can cause cataract. Pilots have a higher risk of cataract.
Which Sunglasses are best for pilots?
A pilot can’t go too far wrong with the following:
- 15% Neutral density filter
- Avoid Photochromatic lenses – the ones that change colour density with the degree of sunlight. There is a time delay between the time when the light changes and the colour change in the lens.
- Avoid Polaroid lenses – it shows up all the invisible scratches on windscreens and cockpit instruments.
- Wide Field of coverage
The following conditions are very common and usually require some sort of visual correction by the optometrist.
The lens becomes less elastic with age and there is difficulty focusing up close.
Presbyopia usually becomes apparent in the age range 45 to 50. This is when glasses need to be worn for reading IFR plates!
The eye is shorter is normal so that the image is projected long of the retina (hence “long sighted”).
Requires Corrective glasses – Similar to the age-related far sightedness of Presbyopia.
The eye is shorter is longer than normal so that the image is projected short of the retina (hence “short sighted”). Treated with glasses, contacts.
Refractive surgery (especiallyfor for Class 1 & 3 medicals) needs a detailed discussion with the Aviation Optometrist. There is a requirement post operatively for a demonstrated period of visual stability.
Light refraction is unequal in the different planes of the eyeball, leading to distorted vision.