Overview
This lecture provides a concise overview of the six classes of U.S. airspace: Class A, B, C, D, E, and G, including their boundaries and primary characteristics.
Introduction to Airspace Classes
- Airspace is categorized into six main classes: A, B, C, D, E, and G, each with distinct rules and altitude ranges.
Class A Airspace
- Class A extends from 18,000 feet MSL (Mean Sea Level) up to and including 60,000 feet MSL.
- It covers the entire U.S. and requires IFR (Instrument Flight Rules) clearance to enter.
Class B Airspace
- Class B surrounds the nation’s busiest airports, typically from the surface up to 10,000 feet MSL.
- Requires explicit ATC (Air Traffic Control) clearance and is shaped like an upside-down wedding cake.
Class C Airspace
- Class C covers airports with moderate traffic, usually from the surface to 4,000 feet AGL (Above Ground Level).
- Requires two-way radio communication with ATC before entry.
Class D Airspace
- Class D airspace is around small airports with towers, typically from the surface to 2,500 feet AGL.
- Requires two-way radio communication with ATC to enter.
Class E Airspace
- Class E fills gaps between other airspace and starts at various altitudes (surface, 700, or 1,200 feet AGL) up to 18,000 feet MSL.
- Used for both IFR and VFR (Visual Flight Rules) operations, but doesn’t require ATC contact for VFR.
Class G Airspace
- Class G is uncontrolled airspace, from the surface to the overlying controlled airspace (often 700 or 1,200 feet AGL).
- No ATC clearance or communication required for VFR operations.
Key Terms & Definitions
- MSL (Mean Sea Level) — Altitude referenced to average sea level.
- AGL (Above Ground Level) — Altitude referenced to the ground directly beneath the aircraft.
- ATC (Air Traffic Control) — Service that directs aircraft in controlled airspace.
- IFR (Instrument Flight Rules) — Flight using instruments for navigation, usually in controlled airspace.
- VFR (Visual Flight Rules) — Flight using visual cues for navigation.
Action Items / Next Steps
- Review airspace diagrams in your textbook or online resources.
- Memorize the altitude ranges, requirements, and communication needs for each airspace class.
- Prepare for Part Two, which may cover special use or additional airspace concepts.