With millions of lives in their hands, airline pilots have a lot to worry about. Vision plays a large role in ensuring that they safely deliver their passengers to their destination, according to Dr. John Henahan, optometrist at Spectrum Eyecare in Peachtree City.
No other profession requires crystal clear vision in such a huge array of lighting conditions. From near zero visibility to suddenly blinding sunlight as the aircraft climbs above the clouds; the eyes of airline pilots are required to perform at a much higher level than most professionals. On top of that, pilots typically do not wear polarized sunglasses when flying because the polarization causes difficulty seeing through the cockpit glass and may make it more difficult to see some instruments.
Night flying and runway approaches challenge the pilot as well. Since maximal night vision is critical when on approach, care must be taken to allow time for full dark adaptation prior to approach. Moreover, eyeglasses lenses that do not take advantage of the latest in HD lens technology as well as anti-glare coatings can interfere with this critical ability to see at night.
The extremely dry environment in the cockpit can cause dry eye related visual disturbances even in those who normally do not suffer from dry eye, especially for contact lens wearers. “It can be quite a challenge to ensure the top performance from their eyes that pilots demand.”, according to Dr. Henahan. With more than ten years practicing in Peachtree City, home to a large population of airline pilots, he has seen many concerns that are commonly expressed by these professionals.
Concerns about clearly viewing instrument clusters, approach plates and flight operations manuals are common, especially in those who are starting to struggle with their close vision. This loss of clarity, known as presbyopia, occurs when one is in their early to mid- forties. While presbyopia is a nearly universal experience, it can be particularly troubling to pilots, since they require clarity at close range both above and below their line of sight. This is in stark contrast to most of us, who only need to see clearly at close range below eye level (think papers on your desk versus instruments both below eye level and overhead in the cockpit). Since most bifocals and progressive lenses are designed to only help with close focus below eye level, special designs are sometimes used for pilots that can help with instruments above and below the line of sight.
While the cockpit glass provides reasonable protection from the sun’s harmful UV rays, radiation levels from the large number of instruments in the cockpit warrant strong protection from UV, even in clear eyeglasses and contact lenses.
Another challenge pertains to the poor comfort with eyeglasses that are not fit with the pilot’s headset in mind. The ensuing hotspots can be very distracting. Both Telex and Dave Clark headsets can cause problems if eyeglasses are not properly fit with the headset in mind.
New advances as well as time-honored strategies can help the pilot maintain excellent vision throughout his or her flying career, allowing the pilot to protect passengers and help to ensure good vision even well into retirement.
Dr. John Henahan is an AOA certified Aviation Vision doctor of optometry practicing and living right here in Peachtree City with his wife and two sons. You may call his office at 770 487-0667 or visit him on the web at Spectrum Eyecare’s website.