The Commission shall have and is hereby given authority in its discretion and under such reasonable rules and regulations as it may prescribe to retire from active service any pilot who shall become physically or mentally unfit to perform a pilot's duties. Provided, however, that no pilot shall be retired, except with his consent for physical or mental disability unless and until such pilots shall have first been examined by the public health officer or county physician of his respective county of residence and such public health officer or physician shall have certified to the board the fact of such physical or mental disability. (1981 (Reg. Sess., 1982), c. 1176, s. 1.)