by Dr. Bill Blank, MD
Senior Aviation Medical Examiner
© Copyright 2023. All rights reserved!
Published in Midwest Flyer Magazine December 2023 Digital Issue
Recently the Federal Air Surgeon, Dr. Susan Northrup, released on YouTube, an “AME Minute” entitled “What are Some Safety Considerations Regarding Sunglasses.” Here are her thoughts along with some of mine.
Sunglasses can protect your eyes from UV radiation, decrease glare, and improve vision during periods of bright light. Pilots are encouraged to wear sunglasses during these conditions. Here are some safety considerations when choosing the type of sunglasses to wear.
Under low light conditions, sunglasses compromise vision. How much can depend upon the color of the tint. Gray reduces overall brightness with the least color distortion.
Photosensitive lenses are unsuitable for aviation purposes because they respond too slowly to changes in light intensity. In the faded state, they might not be clear enough when flying in cloud cover or at night.
Lenses that block blue light can distort aviation lights and displays. Polarized lenses are not recommended, because they interfere with the visibility of instruments with anti-glare filters. Polarized glasses and wind screens don’t mix. They interfere with each other.
There are color vision correcting lenses. They may be worn, but not for the purpose of improving color vision. Go figure! Sunglasses are not acceptable as the only means of correcting visual acuity, but may be used as a backup, if they provide the necessary correction. It is also recommended that you have a non-tinted pair of spare lenses.
Sunglasses sometimes offer UV protection. It’s necessary to research the lenses you are considering. You can’t tell by looking at them. Some very dark brown lenses offer none. You want sunglasses labeled UV 400 which protect wavelengths up to 400 nanometers. This includes 75% to 90% of the visible light from the sun and includes UVA and UVB. UV protection is thought to protect against the formation of cataracts and the development of macular degeneration. I think a more realistic approach is to hope they help delay the onset and slow the progression. The major risk factor for both conditions is age.
I hope this article will help you cho0se the best sunglasses for your purposes. Happy flying!
EDITOR’S NOTE: Columnist William A. Blank is a physician in La Crosse, Wisconsin, and has been an Aviation Medical Examiner (AME) since 1978, and a Senior AME since 1985. Dr. Blank is a retired Ophthalmologist, but still gives some of the ophthalmology lectures at AME renewal seminars. Flying-wise, Dr. Blank holds an Airline Transport Pilot Certificate and has 6000 hours. He is a Certified Flight Instructor – Instrument (CFII) and has given over 1200 hours of aerobatic instruction. In addition, Dr. Blank was an airshow performer through the 2014 season and has held a Statement of Aerobatic Competency (SAC) since 1987. He was inducted into the Wisconsin Aviation Hall of Fame in 2021.
DISCLAIMER: The information contained in this column is the expressed opinion of the author only, and readers are advised to seek the advice of others, including their own AME, and refer to the Federal Aviation Regulations and FAA Aeronautical Information Manual for additional information and clarification.
