Sec. 78.3. Unauthorized commercial activity prohibited

(a) No person shall carry on any commercial activity at the airport without the written consent of the airport operator.

(b) No one basing or otherwise maintaining an aircraft at the airport shall permit it to be used for a commercial activity conducted at or out of the airport, unless such commercial activity is expressly authorized by the terms of an agreement with the airport operator or with a fixed base operator who has obtained the airport operator's approval. In addition, no one basing or otherwise maintaining an aircraft at the airport shall permit such aircraft to be serviced, cleaned, repaired, or otherwise worked upon by private entrepreneurs other than those operating at the airport pursuant to an agreement with the airport operator or with a fixed base operator with the airport operator's approval. Notwithstanding the foregoing, such aircraft may be use by duly licensed flight training instructors for the purpose of training or otherwise increasing the flying proficiency of the person basing or otherwise maintaining the aircraft at the airport and the members of that person's immediate family. However, no person shall permit an aircraft based or maintained at the airport to be used for commercial flight instruction without the written approval of the airport operator.