(a) Permit.--Any airport zoning regulations shall require that a permit be obtained before any new use or structure may be established or constructed and before any existing use or structure may be substantially changed, but no permit may be required to make maintenance repairs to or to replace parts of existing structures which do not enlarge or increase the height of an existing structure. However, all regulations shall provide that before any nonconforming structure may be replaced, substantially altered or rebuilt or tree allowed to grow higher or replanted, a permit must be secured from the municipality authorizing the replacement or change. Applications for permits shall only be granted unless to do so would allow the establishment or creation of an airport hazard or permit a nonconforming structure or object of natural growth or nonconforming use to be made or become higher or become a greater hazard to air navigation than it was when the applicable regulation was adopted, or than it is when the application for a permit is made.

(b) Variance.--Any person desiring to erect any structure or increase the height of any structure or permit the growth of any object of natural growth or otherwise use his property in violation of airport zoning regulations may apply to the board for a variance from the zoning regulations in question. A variance shall only be granted after the requirements of section 5919 (relating to notice to department) are satisfied. A variance may be allowed where a literal application or enforcement of the regulations would result in practical difficulty or unnecessary hardship and the relief granted would not be contrary to the public interest but would do substantial justice and would be in accordance with the spirit of the regulations and this subchapter. Any variance may be granted subject to any reasonable conditions that the board may deem necessary to effectuate the purposes of this subchapter.

(c) Hazard marking and lighting.--In granting any permit or variance under this section, the board shall, if it deems the action advisable to effectuate the purpose of this subchapter and reasonable in the circumstances, so condition the permit or variance as to require the owner of the structure or object of natural growth in question to permit the municipality, at its own expense, or require the person or persons requesting the permit or variance, to install, operate and maintain thereon such markers and lights as may be required by guidelines or regulations adopted by the Federal Aviation Administration of the United States Department of Transportation.

Cross References. Section 5916 is referred to in section 5915 of this title.