(1) Site approvals. — Except as provided in this section, the commission is authorized to provide for the approval of airport sites and the issuance of certificates of such approvals. No charge shall be made for any such approval, and certificates of such an approval shall be issued without charge to all persons requesting them. Upon the promulgation of a rule or regulation providing for such approvals, any municipality or person desiring or planning to construct or establish an airport may, prior to the acquisition of the site or prior to the construction or establishment of the proposed airport, make application to the commission for approval of this site. The commission shall, with reasonable dispatch, grant approval of a site if it is satisfied: (a) that the site is adequate for the proposed airport; (b) that such proposed airport, if constructed or established, will conform to minimum standards of safety; and (c) that safe air traffic patterns could be worked out for such proposed airport and for all existing airports and approved airport sites in its vicinity. An approval of a site may be granted subject to any reasonable conditions which the commission may deem necessary to effectuate the purposes of this section, and shall remain in effect, unless sooner revoked by the commission, until a license for an airport located on the approved site has been issued pursuant to this section. The commission may, after notice and opportunity for hearing to holders of certificates of an approval, revoke such approval when it shall reasonably determine (1) that there has been an abandonment of the site as an airport site, or (2) that there has been a failure within the time prescribed, or if no time was prescribed, within a reasonable time, to develop the site as an airport or to comply with the conditions of the approval, or (3) that because of change of physical or legal conditions or circumstances the site is no longer usable for the aeronautical purposes for which the approval was granted. No approval shall be required for the site of any existing airport.

(2) Optional public hearings. — In connection with the grant of approval of a proposed airport site or the issuance of an airport license under the provisions of this section, the commission may, on its own motion or upon the request of an affected or interested person, hold a hearing open to the public as provided in this section.

(3) Exemptions. — The provisions of this section shall not apply to airports owned or operated by the United States or its agencies. The commission may, from time to time, to the extent necessary, exempt any other class of airports, pursuant to a reasonable classification or grouping, from any rule or regulation promulgated under this section or from any requirement of such a rule or regulation, if it finds that the application of such rule, regulation or requirement would be an undue burden on such class and is not required in the interest of public safety.