Subject to the budget and fiscal provisions of this Charter:
(a) The entire gross revenue of the Airport Commission shall be set aside and deposited into a fund in the City and County treasury to be known as the "Airport Revenue Fund." All amounts paid into the Fund shall be maintained by the Treasurer separate and apart from all other City and County funds and shall be secured by the Treasurer's official bond or bonds.
Separate accounts shall be kept with respect to receipts and disbursements of each airport under the jurisdiction of the Commission.
(b) Monies in the Airport Revenue Fund including earnings thereon shall be appropriated, transferred, expended or used for the following purposes pertaining to the financing, maintenance and operation of airports and related facilities owned, operated or controlled by the Commission and only in accordance with the following priority:
1. The payment of operation and maintenance expenses for such airports or related facilities;
2. The payment of pension charges and proportionate payments to such compensation and other insurance or outside reserve funds as the Commission may establish or the Board of Supervisors may require with respect to employees of the Commission;
3. The payment of principal, interest, reserve, sinking fund and other mandatory funds created to secure revenue bonds hereafter issued by the Commission for the acquisition, construction or extension of airports or related facilities owned, operated or controlled by the Commission;
4. The payment of principal and interest on general obligation bonds heretofore or hereafter issued by the City and County for airport purposes;
5. Reconstruction and replacement as determined by the Commission or as required by any airport revenue bond ordinance duly adopted and approved;
6. The acquisition of land, real property or interest in real property for, and the acquisition, construction, enlargement and improvement of new and existing buildings, structures, facilities, utilities, equipment, appliances and other property necessary or convenient for the development or improvement of any airports and heliports owned, controlled or operated by the Commission in the promotion and accommodation of air commerce or navigation and matters incidental thereto;
7. The return and repayment into the General Fund of the City and County of any sums paid by the City and County from funds raised by taxation for the payment of interest on and principal of any general obligation bonds previously issued by the City and County for the acquisition, construction and improvement of the San Francisco International Airport;
8. For any other lawful purpose of the Commission including, but not limited to, transfer to the General Fund during each fiscal year of 25 percent, or such lesser percentage as the Board of Supervisors shall establish, of the non-airline revenues as a return upon the City and County's investment in the Airport. "Non-airline" revenues means all airport revenues from whatever source less revenues from airline rentals and charges to airlines for use of Airport facilities.