CIVIL AVIATION AUTHORITY
With special thanks to Adrian Chorley (BSc.MCOptom) for his assistance in setting up this list.

  • VISUAL ACUITY REQUIREMENTS FOR PRIVATE PILOTS
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  • VISUAL ACUITY REQUIREMENTS FOR PROFESSIONAL PILOTS
  • SEE FURTHER NOTES ON REFRACTIVE SURGERY and TEST STANDARDISATION
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    The following are excerpts from the standards issued by the Joint Aviation Authorities. They should not be taken as a definitive statement of the full regulations. For further information contact the CAA medical department at Aviation House, Gatwick Airport South, West Sussex, RH6 0YR; tel. 01293 573683; fax 01293 573995.
    These standards apply to all new applicants in applicable categories from April 1999 and the renewal of medical certificates from July 1st 1999.
    Under the new system, the Joint Aviation Requirements (JAR), there are two classes of medical assessment as follows:-
    Class 1Commercial pilot (aeroplane and helicopter), Airline transport pilot (aeroplane and helicopter)
    Class 2Private pilot (aeroplane and helicopter)

    The visual standards for Air Traffic Control Officers, Flight Engineers, Flight Navigators, Balloon Operators (passenger carrying) and microlight pilots are still covered by UK guidelines, which are unchanged from the previous UK standards.

    JAR Class 1 (Commercial pilot [aeroplane and helicopter], Airline transport pilot [aeroplane and helicopter])
    1. There shall be no abnormality of the function of the eyes or their adnexae, or any active pathological condition, congenital or acquired, acute or chronic, or any sequelae of eye surgery or trauma, which is likely to interfere with the safe exercise of the privileges of the applicable license.
    2. A comprehensive ophthalmological examination is required at the initial examination.
    3. A routine eye examination shall form part of all re-validation and renewal examinations.
    4. A comprehensive ophthalmological examination is required in conjunction with re-validation and renewal examinations at the following intervals:
      1. every five years to the 40th birthday
      2. once every two years thereafter
      CAA appointed doctors (Authorised Medical Examiners) can undertake ophthalmological assessments on pilots up to the age of 50 years after which slit lamp examination and tonometry will be required.
    5. Distant visual acuity, with or without correction, shall be 6/9 or better monocularly, and 6/6 or better binocularly.
    6. If the visual requirement is met only with the use of correction, the spectacles or contact lenses must provide optimal visual function and should be suitable for aviation purposes.
    7. At initial examination the refractive error shall not exceed +/-3.00 dioptres along the most ametropic meridian with no more than +/-2.00 dioptres astigmatic component and no more than 2.00 Dioptres of anisometropia.
    8. If the refractive error is within the range -3/-5 dioptres, the Aeromedical Section may consider Class I certification if:
      1. no significant pathology can be demonstrated.
      2. the refraction has remained stable for at least four years after the age of 17 years.
      3. visual correction by contact lenses has been considered.
      4. experience satisfactory to the Authority has been demonstrated.
    9. An applicant shall be able to read N5 at 30-50cms and N14 at 100cms with correction if prescribed.
    10. An applicant with diplopia or significant defects of binocular vision shall be assessed as unfit. There is no requirement for stereopsis.
    11. Monocularity entails unfitness for Class I certificate. Central vision in one eye below the limits may be considered for Class I re-certification if binocular visual fields are normal and the underlying pathology is acceptable according to ophthalmic specialist assessment. A satisfactory flight test is required and operations limited to multi-pilot only.
    12. An applicant with convergence which is not normal shall be assessed as unfit.
    13. An applicant with heterophorias exceeding limits (see table) shall be assessed as unfit unless the fusional reserves are sufficient to prevent asthenopia and diplopia.
    14. An applicant with visual fields which are not normal shall be assessed as unfit.
    15. An applicant shall have normal perception of colours (defined as no mistakes on Ishihara plates (24 plate version) tested in daylight or in artificial light of the same colour temperature such as that provided by illuminant "C" or "D") or be colour safe. Applicants who fail Ishihara shall be assessed as colour safe if they pass extensive testing with methods acceptable to the Aeromedical Section (Holmes-Wright lantern or anomaloscopy).
    16. An applicant who fails the acceptable colour perception tests is to be considered colour unsafe and shall be assessed as unfit.

    Any spectacles necessary must be 'available for immediate use', and so there is no time to take them on or off. An applicant who needs a correction to meet the near visual acuity will require 'look-over', or multifocal lenses in order to read the instruments and a manual held in the hand, and also to make use of distance vision through the windscreen without removing the lenses. The CAA accepts all forms of spectacle correction except that of a single vision full lens for near.

    An applicant is expected to advise the optometrist of relevant reading distances for the flight deck. The occupational needs may then be fulfilled by bifocal, trifocal or varifocal lenses. On occasions an intermediate correction in the upper field may be required, which may be accomplished by a segment of the relevant power in addition to the bifocal or varifocal design. Flip-up spectacles are also acceptable.

    Sunglasses may often be required and their use is encouraged. Tints should be neutral grey, but polarised lenses are not permitted and photochromic lenses are discouraged. An additional pair of untinted spectacles must be carried.

    Contact lenses are permissible, but if soft lenses are used, they should not be high water content due to the low relative humidity of the cockpit (often <15%). Bifocal contact lenses are not approved.

    JAR Class 2 (Private pilot [aeroplane and helicopter])
    1. There shall be no abnormality of the function of the eyes or their adnexa, or any active pathological condition, congenital or acquired, acute or chronic, or any sequela of eye surgery or trauma, which is likely to interfere with the safe exercise of the privileges of the applicable license.
    2. At examination, an applicant requiring visual correction to meet the standards shall submit a copy of the current spectacle prescription.
    3. At each aeromedical renewal examination, an assessment of the visual fitness of the license holder shall be performed and the eyes shall be examined with regard to possible pathology. All abnormal and doubtful cases shall be referred to a specialist in aviation ophthalmology acceptable to the Aeromedical Section.
    4. Distant visual acuity, with or without correction, shall be 6/12 or better monocularly, and 6/6 or better binocularly. No limits apply to uncorrected visual acuity.
    5. If the visual requirement is met only with the use of correction, the spectacles or contact lenses must provide optimal visual function and should be suitable for aviation purposes.
    6. At initial examination the refractive error shall not exceed +/-5.00 dioptres along the most ametropic meridian with no more than +/-3.00 dioptres astigmatic component and no more than 3.00 dioptres of anisometropia.
    7. If the refractive error is within the range -5/-8 dioptres, the Aeromedical Section may consider Class II certification if:
      1. no significant pathology can be demonstrated.
      2. the refraction has remained stable for at least four years after the age of 17 years.
      3. visual correction by contact lenses has been considered.
    8. An applicant shall be able to read N5 at 30-50cms and N14 at 100cms with correction if prescribed.
    9. An applicant with diplopia or significant defects of binocular vision shall be assessed as unfit. There is no requirement for stereopsis.
    10. In an applicant with amblyopia, the visual acuity of the amblyopic eye shall be 6/18 or better and may be accepted as fit provided the visual acuity in the other eye is 6/6 or better. In the case of reduction of vision in one eye to below the limits, re-certification may be considered if underlying pathology and the visual ability of the remaining eye are acceptable following ophthalmic evaluation acceptable to the Aeromedical Section and subject to a satisfactory medical flight test, if indicated.
    11. An applicant with visual fields which are not normal shall be assessed as unfit.
    12. An applicant shall have normal perception of colours (defined as no mistakes on Ishihara plates (24 plate version) tested in daylight or in artificial light of the same colour temperature such as that provided by illuminant "C" or "D") or be colour safe. Applicants who fail Ishihara shall be assessed as colour safe if they pass extensive testing with methods acceptable to the Aeromedical Section (Holmes-Wright lantern or anomaloscopy).
    13. An applicant who fails the acceptable colour perception tests is to be considered colour unsafe and shall be assessed as unfit.
    14. A colour unsafe applicant may be assessed by the Aeromedical Section as fit to fly within the flight information region of Joint Aviation Authority member states, visual flight rules by day only.

    Any spectacles necessary must be 'available for immediate use', and so there is no time to take them on or off. An applicant who needs a correction to meet the near visual acuity will require 'look-over', or multifocal lenses in order to read the instruments and a manual held in the hand, and also to make use of distance vision through the windscreen without removing the lenses. The CAA does not proscribe any type of visual correction except a single vision full lens near correction. All types of contact lenses except bifocal are permissible.

    An applicant is expected to advise the optometrist of relevant reading distances for the flight deck. The occupational needs may then be fulfilled by bifocal, trifocal or varifocal lenses. On occasions an intermediate correction in the upper field may be required, which may be accomplished by a segment of the relevant power in addition to the bifocal or varifocal design. Flip-up spectacles are also acceptable.

    Sunglasses may often be required and their use is encouraged. Tints should be neutral grey, but polarised lenses are not permitted and photochromic lenses are discouraged. An additional pair of untinted spectacles must be carried.

    Note

    Refractive surgery entails unfitness. Re-certification for class I and certification for Class II may be considered by the Aeromedical Section 12 months after the date of refractive surgery provided that:

    1. pre-operative refraction was less than 5 dioptres.
    2. satisfactory stability of refraction has been achieved (less than 0.75 dioptres variation diurnally).
    3. glare sensitivity is not increased.

    To achieve uniformity in the measurement of visual acuity the following shall be adopted:

    1. In a lighted room, the test illumination level will be approximately 50 lux, normally corresponding to a brightness of 30 candelas per square metre.
    2. Visual acuity should be measured by means of a series of optotypes of Landolt, or similar optotypes at a distance of five or six metres from the candidate with the appropriate chart for the distance.