US-FAA14 CFR 71.61
Class D airspace
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The Class D airspace areas listed in subpart D of FAA Order JO 7400.11K (incorporated by reference, see § 71.1) consist of specified airspace within which all aircraft operators are subject to operating rules and equipment requirements specified in part 91 of this chapter. Each Class D airspace area designated for an airport in subpart D of FAA Order JO 7400.11K (incorporated by reference, see § 71.1) contains at least one primary airport around which the airspace is designated.
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