Ala. Code § 22-21-144
The principal of, and the interest on, the bonds shall be secured by a pledge of the revenues out of which the bonds shall be made payable, may be secured by a pledge of the lease agreement (if any) covering the project from which revenues so pledged shall be derived and by a pledge of the rental from such project and may be secured by a nonforeclosable indenture covering the project or projects out of the revenues from which the bonds are made payable. The trustee, under any indenture, may be a trust company or bank having trust powers, whether located within or without the state, and may be selected by the board without regard to the provisions of Chapter 25 of Title 36 of this code or other similar law. The indenture may contain any agreements and provisions customarily contained in instruments securing evidences of indebtedness including, without limiting the generality of the foregoing, provisions respecting the collection, segregation and application of the revenues and rental from any project or projects covered by such indenture, the terms to be incorporated in any lease agreement respecting any project, the maintenance and insurance on any project, the creation and maintenance of special funds from the revenues and rental of any project and the rights and remedies available in the event of default to the holders of the bonds or the trustee under the indenture, all as the board shall deem advisable and as shall not be in conflict with the provisions of this article; provided, that in making any such agreements or provisions, the authority shall not have the power to obligate itself except with respect to the project or projects out of the revenues from which the bonds are made payable and the application of the revenues therefrom. The indenture may contain provisions regarding the rights of any trustee thereunder and the holders of the bonds and coupons and may contain provisions restricting the individual rights of action of the holders of the bonds and coupons.
Ala. Code § 22-21-144 (1975)