Policy information sourced from the Hillingdon Local Plan: Part 1
A4 New Development Directly Related to Heathrow Airport
New development directly-related to Heathrow airport should normally be within its boundary and will not normally be permitted outside the airport. Development not directly-related to the operation of the airport will not be permitted within its boundary. For the purposes of this policy, directly-related development includes passenger and cargo terminals, maintenance facilities, oil storage depots, administrative offices, warehousing, storage and distribution facilities, car parking and catering facilities.
For more information please see Appendix 5 of the Local Plan: Part 1