Ala. Code § 4-3-80
Any incorporated city or town in this state may borrow money to the extent of its constitutional debt limit for the purpose of providing funds to enable or assist any airport authority incorporated as a public corporation with the consent and approval of such city or town to acquire, own and operate any airport, including related facilities, situated within or without the corporate limits of such city or town or partly within or without such limits and to pay all costs, fees and commissions agreed upon in connection with any such loans, and the governing body thereof may, without an election, issue evidences of its indebtedness in the form of interest-bearing warrants, notes or bills payable, maturing at such time or times as such governing body may determine, not exceeding 20 years from the date of issue, and any such city or town may, as security for any such evidences of indebtedness and as a part of the contract whereunder any money is borrowed, agree to annually levy, collect and apply to the payment thereof, so long as the same or any part thereof remains unpaid, any special tax or license authorized on the date of such contract to be levied and collected.
Ala. Code § 4-3-80 (1975)