Before any nonconforming structure may be replaced, substantially altered or rebuilt within any airport protected airspace, a permit must be secured authorizing such replacement or change. Such permit shall be granted except where the granting thereof would allow the establishment or creation of an airport hazard, or permit a nonconforming use or structure to be made or become higher or become a greater hazard to air navigation than existed on the effective date of the applicable regulation thereunder. In case of emergencies affecting the public welfare or safety or the preservation of property, any nonconforming structure may be replaced or repaired without first obtaining a permit; provided, that an application for a permit is filed with the Department of Aviation within twenty-four (24) hours after such Department is first opened subsequent to the emergency. (Repealed and reenacted by Ord. 2644, § 2 (Att. 1), 6/23/2020)