UA.II.A.K1b

From the FAA library

• Aeronautical Information Manualp. PCG C-3
  Pilot/Controller Glossary › C

  CLASS A AIRSPACE- (See CONTROLLED AIRSPACE.) CLASS B AIRSPACE- (See CONTROLLED AIRSPACE.) CLASS C AIRSPACE- (See CONTROLLED AIRSPACE.) CLASS ... AIRSPACE- (See CONTROLLED AIRSPACE.) CLASS E AIRSPACE- (See CONTROLLED AIRSPACE.) CLASS G AIRSPACE- Airspace that is not designated in 14 CFR part 71 as Class A, Class B, Class C, Class D, or Class E controlled airspace is Class…

• Pilot's Handbook of Aeronautical Knowledgep. 15-2
  Chapter 15: Airspace › Controlled Airspace › Class C Airspace

  Class C Airspace Class C airspace is generally airspace from the surface to 4,000 feet above the airport elevation (charted in MSL) surrounding those airports that have an operational control tower, are serviced by a radar approach control ... facility providing air traffic services prior to entering the airspace and thereafter must maintain those communications while within the airspace. Class D Airspace Class D airspace is generally airspace from the surface to 2,500 feet above the airport elevation…

• Aeronautical Information Manualp. 3-2-5
  Chapter 3. Airspace › Section 2. Controlled Airspace › 3-2-4. Class C Airspace

  workload or traffic conditions prevent immediate provision of Class C services, the controller will inform the pilot to remain outside the Class C airspace until conditions permit the services to be provided. 3. It is important to understand that ... from the primary Class C airspace airport. Its vertical limit extends from the lower limits of radio/radar coverage up to the ceiling of the approach control’s delegated airspace, excluding the Class C airspace itself, and other airspace as appropriate…