The Commission, each commissioner, or their designees at any reasonable time shall have the right to inspect the property, plant and facilities of any radio common carrier, and to inspect or audit at reasonable times the accounts, books, papers and documents of any radio common carrier, and for the purposes herein mentioned are authorized to examine under oath any officer, agent or employee of such radio common carrier in relation to the business and affairs of such radio common carrier, but written record of the testimony or statement so given under oath shall be made and filed with the Commission. Any person other than a commissioner demanding the right to perform any act authorized by this section shall produce written authority from the Commission authenticated by its seal.