The Department of Transportation is delegated authority to lease the following types of special purpose space (or real property):
(a) Land for the Federal Aviation Administration (FAA) at airports (unimproved land may be leased only on a fiscal year basis).
(b) General purpose office space not exceeding 10,000 square feet for the FAA at airports in buildings under the jurisdiction of public or private airport authorities (lease terms, including all options, limited to 5 years).