(1) Each commissioner of a regional or municipal airport authority may receive from that airport authority per diem compensation in the amount provided by Section 25-3-69 for each day or fraction of a day engaged in attendance of meetings of the authority or engaged in other official duties of the authority, not to exceed one hundred twenty (120) days in any one (1) year, and may receive from the airport authority actual traveling expenses incurred in the discharge of his duties. Each commissioner shall hold office until his successor has been appointed and has qualified. The certificates of the appointment and reappointment of commissioners shall be filed with the authority.

(2) The powers of each authority shall be vested in the commissioners of that authority. A majority of the commissioners of an authority shall constitute a quorum for the purpose of conducting the business of the authority and exercising its powers and for all other purposes. Action may be taken by the authority upon a vote of not less than a majority of the commissioners present. There shall be elected a chairman and vice chairman from among the commissioners.

(3) The commissioners of an authority shall designate an executive director, who shall be the chief executive officer of the authority and shall perform those duties as are required by law and any other duties as may be assigned by the commissioners. The commissioners may designate the executive director as the purchasing agent of the authority. If so designated, the executive director shall have the authority of the purchasing agent of a state agency under Section 31-7-13.