The Town and Country Planning (General Permitted Development) (England) Order 2015

Class I – emergency use of land by the Crown connected with air traffic servicesE+W

Permitted developmentE+W

I   The use of land by or on behalf of the Crown in an emergency to station moveable apparatus replacing unserviceable apparatus in connection with the provision of air traffic services.

ConditionE+W

I.1  Development is permitted by Class I subject to the condition that on or before the expiry of a period of 6 months beginning with the date on which the use began, the use ceases, and any apparatus is removed, and the land is restored to its condition before the development took place, or to such other state as may be agreed in writing between the local planning authority and the developer.