2024-12-03
Flying With Glasses Is Common. Getting the Right Glasses Is Not.
A significant number of licensed pilots in Canada wear corrective lenses. Transport Canada allows it, provided you meet the vision standards for your medical category and carry a spare pair in the cockpit. But while the regulations tell you that you can fly with glasses, they do not tell you much about which glasses actually work well in an aircraft. That is where things get interesting, because the cockpit environment creates some very specific optical problems.
What Transport Canada Actually Requires
Let us get the regulatory side out of the way first. For a Category 1 medical (airline transport pilots), Transport Canada requires distance visual acuity of 20/20 in each eye, corrected or uncorrected. Category 3 (private pilots) requires 20/30 in each eye. If you need glasses to meet these standards, your medical certificate will carry a "must wear corrective lenses" restriction, and you are required to have a spare pair available in the cockpit during flight.
There are no specific regulations about frame style, lens material, or coatings. The restriction is simply that you must be able to see to the required standard. However, the Canadian Aviation Medical Examiner (CAME) who does your medical can flag concerns about lens tints or coatings if they believe they impair your vision in flight conditions.
Why Polarized Lenses Are a Problem
This is the single most important thing for pilots to understand about their eyewear: polarized lenses can make LCD displays invisible.
Polarized lenses work by blocking light waves oriented in a particular direction, which is brilliant for cutting glare off water, roads, and car hoods. The problem is that LCD screens (which include most modern glass cockpit displays, GPS units, tablets, and smartphones) emit polarized light. When the polarization axis of your lenses crosses the polarization axis of the screen, the display goes partially or completely dark.
Tilt your head 45 degrees while wearing polarized sunglasses and looking at your phone. See how the screen darkens or changes colour? Now imagine that happening to your primary flight display while you are in IMC. That is why polarized lenses are strongly discouraged, and effectively banned by most aviation authorities, for cockpit use.
Bottom line: Do not wear polarized lenses in the cockpit. Not for your clear prescription glasses (some anti-reflective coatings have a very mild polarizing effect, which is fine), but absolutely not for sunglasses. Non-polarized gradient tint or solid tint lenses are the safe choice.
Lens Tints for Aviation
The sky above 10,000 feet is remarkably bright. UV exposure is significantly higher at altitude, and glare from cloud tops can be intense. You need sun protection, but the wrong tint can distort your colour perception, which matters when you need to identify runway lights, traffic, and instrument indications.
Here is what works:
- Grey/neutral grey is the gold standard for aviation sunglasses. It reduces brightness evenly across the colour spectrum without shifting hues. You see everything in its true colour, just dimmer.
- Green (G-15) is the classic pilot sunglass tint (think original aviators). It slightly enhances contrast while keeping colour perception mostly accurate. Works well in most conditions.
- Brown/amber enhances contrast more than grey, which can help with seeing terrain features and traffic against a blue sky. However, it does shift colour perception, so some pilots avoid it for instrument flying.
Tints to avoid in the cockpit: yellow (distorts colour perception significantly, makes blue instruments hard to read), rose/red (same problem), and any tint dark enough to impair your vision in lower light conditions. You should be able to read all cockpit instruments clearly through your tinted lenses.
Frame Considerations for the Cockpit
Headset Compatibility
Aviation headsets, whether David Clark, Bose A20, or Lightspeed, clamp firmly over your ears with significant pressure. The ear seals need to form a tight seal for noise attenuation, and eyeglass temple arms running under the seal break that seal and create pressure points.
The classic solution is the bayonet temple, a straight, thin temple arm that runs straight back to hook behind the ear rather than curving around it. This design slides under headset ear seals with minimal disruption. The original Randolph Engineering Aviator and American Optical Original Pilot both use bayonet temples, and there is a reason they have been the default pilot frame for decades.
If bayonet temples are not your style, look for frames with:
- Thin metal or titanium temple arms (under 3 mm wide)
- Minimal curvature behind the ear
- No thick acetate or chunky end pieces
Full Rim vs. Semi-Rimless vs. Rimless
There is no regulatory preference, but practically speaking, full-rim frames are more durable (important for a spare pair rattling around in your flight bag), and they provide a more defined edge to your field of view. Some pilots prefer rimless for the unobstructed peripheral vision, especially in a busy traffic pattern. Semi-rimless is a reasonable middle ground.
Frame Size
Pilot sunglasses traditionally have large lenses, and there is a practical reason for it. In the cockpit, you are constantly scanning a wide visual field: instruments below, traffic ahead and above, and side windows for traffic patterns. Small, fashionable lenses leave gaps where bright unfiltered light sneaks in around the edges, causing your pupils to constrict unevenly and making it harder to see instruments in the shade of the cockpit.
A lens height of at least 45-50 mm provides good coverage without being comically large.
Progressive Lenses in the Cockpit
This is a real challenge for pilots over 45. The cockpit demands clear distance vision (looking outside), clear intermediate vision (instrument panel at roughly 70-80 cm), and sometimes near vision (approach plates, kneeboard notes). Standard progressives can work, but the intermediate zone is often too narrow for comfortable instrument scanning.
Several lens manufacturers offer aviation-specific progressive designs with an expanded intermediate zone. These sacrifice some of the near reading area to give you a wider, more usable instrument panel zone. If your optician is not familiar with these, ask specifically about occupational progressives configured for a cockpit distance layout.
Some pilots carry two pairs: a single-vision distance pair for visual flying and a progressive pair for IFR work where they need to read instruments and approach plates. It is not the most elegant solution, but it works.
Carry a Spare
Transport Canada requires it, and it is genuinely good practice. Your spare pair does not need to be fancy, but it needs to be current. If your prescription changed six months ago, update both pairs. Keep the spare in a hard case in your flight bag where it will not get crushed, scratched, or lost. A scratched, outdated spare pair in a soft pouch at the bottom of your bag is not really meeting the spirit of the requirement.
If you are a pilot and you need eyewear that actually works in the cockpit, come talk to us. We can set you up with the right tint, the right frame profile for your headset, and the right lens design for your flying. Bring your headset if you can, so we can check the fit together.