Any corporation or association, presently existing, and any that may hereafter be organized or authorized to do business under the laws of this state, or any lessee, or trustee, or any person or persons owning, conducting, managing, operating, or controlling any air carrier engaged in intrastate commerce, may issue stocks and bonds, notes, or other evidences of indebtedness, payable at periods of more than twelve (12) months after the date thereof, only when there shall have been secured from the administrator an order authorizing the issue. Any person, corporation, or association desiring authority to issue stocks or bonds, notes, or other evidences of indebtedness shall make written application therefor to the administrator in such form as the administrator may require. The administrator shall thereafter make such inquiry or investigation as he or she may deem necessary, and the administrator may hold such hearings and examine such witnesses’ books, papers, documents, or contracts as he or she may deem of importance, for the purpose of enabling him or her to reach a determination. The administrator shall authorize the issuance of the stocks or bonds, notes, or other evidences of indebtedness, if he or she shall be shown that the funds to be so realized are necessary for the acquisition of property, the construction, completion, extension, or improvement of facilities, or for the improvement or maintenance of service, or for the discharge or lawful refunding of obligations, or for any other proper purpose.