Unless otherwise authorized by the airport manager, no aircraft or vehicle maintenance (other than required to remove damaged aircraft from the runway or taxiway, or replacing a flat tire) shall be performed on the Sierraville-Dearwater Airport except in areas specifically designated by the airport manager for that purpose. Engine run-ups not incidental to takeoff or landing shall not be conducted between the hours of 10:00 p.m. to 6:00 a.m.