Visual requirements are strict across the board, regardless of your country of origin or service of choice -- but to become approved by the Federal Aviation Administration (F.A.A), (an extension of the United States Department of Transportation (USDOT) for piloting commercial flights originating within the United States, you will need to take a comprehensive visual test by an Aviation Medical Examiner. In order to get a first class FAA Medical Certificate (required in order to pilot commercial passenger airliners) you must have at least:
Distant-Range vision of 20/20 or better in each eye separately, with or without correction.
Intermediate-Range vision of 20/40 or better in each eye separately, with or without correction, as measured at 32 inches.
You will also need Color Vision and to demonstrate your ability to perceive the colors necessary for the performance of airman duties. Essentially, the FAA requires you to have good enough color vision to identify important things like aircraft position lights, airport beacons, Radar, Flight Charts and associated chart symbols, and various other signal markers.
Like the U.S's Commercial Pilots, you will need to visit an authorized Medical Examiner (A.M.E) To qoute caa.uk on eye examination requirements:
"An applicant may be assessed as fit with hypermetropia not exceeding +5.0 dioptres, myopia not exceeding -6.0 dioptres, astigmatism not exceeding 2.0 dioptres, and anisometropia not exceeding 2.0 dioptres, provided that optimal correction has been considered and no significant pathology is demonstrated. Monocular visual acuities should be 6/6 or better."
They then continue to go on to specify:
"Distant visual acuity, with or without correction, shall be 6/9 or better monocularly, and 6/6 or better binocularly. Initial applicants who do not meet these requirements should be referred to the licensing authority. A fit assessment may be considered following review by an ophthalmologist which may still allow them to fly.”
“You will require a comprehensive ophthalmological examination on your initial assessment then every 5 years up to your 40th Birthday and then every 2 years."
The Civil Aviation Administration of China (CAAC) relaxed its exceptionally high physical requirements for pilot candidates in recent years, especially regarding height, weight, and visual abilities as recently as September 2017.
This change should enable more candidates to pass the physical examination than previously.
The biggest challenges for candidates are still the eyesight requirements, as the Civil Aviation Medical Center informs us, that is what disqualifies the majority of candidates. On a related note, almost 47% of all people in the world who suffer from myopia are Chinese. The new requirements decrease the standard for uncorrected distance vision from 0.3 to 0.1, although once corrected vision requirements remain at 1.0 - allowing for more people to pass.
Candidates who had vision correction surgery (LASIK or PRK) will also be able to apply, as long as they meet standard acuity requirements.
According to the USAF website, pilots must have:
Navy pilots must pass a “Class I Flying Physical.” (the same one administered to Marine Corps. pilots.)
To become a pilot in the Navy or Marine Corps, an applicant's uncorrected vision must be 20/40 (correctable to 20/20) in each eye. Once flight training begins, vision can deteriorate to no worse than 20/100 (correctable to 20/20) in each eye before disqualification. After flight training graduation, if the eyesight deteriorates to worse than 20/200 (also correctable to 20/20), the pilot will require a waiver for carrier operations. If the pilot's vision deteriorates past 20/400 (but remains correctable to 20/20), the pilot is restricted to aircraft with dual controls.
For Navigators (called "NFOs" or "Navy Flight Officers"), there is no vision requirement to enter flight training… However, the Navigator's vision must be correctable to 20/20 (whatever it is) and there are limits on refraction. Refraction must be less than or equal to plus or minus 8.00 (sphere) in any meridian and less than or equal to minus 3.00 cylinder. No more than 3.50 (regarding anisometropia.) After flight training, to continue on flight status there is no limit on refraction for NFOs.
No waivers are authorized for NFO applicants who exceed these refraction limits.
Normal color vision is required for both NFOs and regular military pilots. Normal depth perception is required for pilots and pilot applicants, and the Navy allows for both LASIK and PRK laser eye surgery, both for current pilots and NFOs and for pilot/NFO applicants - though this is a recent change that they were fairly slow to adapt.
I wanted to join the U.S army as a pilot once upon a time. So I can tell you, and It shall further be noted that the army itself has very few fixed-wing aircraft. The vast majority of army pilots training today are training to become helicopter pilots. Army aviators must pass a “Flight Class I Flying Physical.” Part of that is a visual test. To enter army helicopter flight training, as either a commissioned officer or warrant officer, the applicant can have vision no worse than 20/50 (correctable to 20/20, just like everywhere else) in each eye. After flight training, pilots can remain on flight status as long as their vision does not deteriorate beyond 20/400 (correctable to 20/20).
Normal depth perception and normal color vision are of course also required.
Like the other branches, it is possible to apply for army flight training and remain on flight status with laser eye surgery, especially if one is accepted into the army's “aviator laser eye surgery study” program.
For most countries, most of the time - the answer is yes!
If they are prescribed lenses, it is actually no doubt required that you wear them, and even that you keep a spare. For commercial airlines, the Federal Aviation Administration (FAA) definitely requires it - in the case of pilots with refractive errors that affect their distance vision - to not only have and wear prescription eyeglasses or contact lenses that correct vision to 20/20, but to (as was previously noted) keep a spare set with them in case they lose or destroy their primary pair, in the case that they effectively correct and improve vision.
For pilots with refractive visual errors or presbyopia, they recommend progressive lenses.
Mono-lenses, however, are not allowed as they impair binocular vision.