Class A Airspace
Class A airspace sits at the very top of the National Airspace System, and it is the one class a standard Part 107 operation will never actually encounter. This lesson is intentionally short ? its purpose is completeness of the airspace system, and understanding precisely why Class A doesn't factor into everyday sUAS operations.
Where Class A airspace begins and ends
Class A airspace extends from 18,000 feet mean sea level (MSL) up to and including flight level 600 (FL600, or 60,000 feet MSL). It covers the entire conterminous United States uniformly at these altitudes ? unlike Class B, C, or D, which are located around specific airports, Class A exists everywhere above 18,000 feet MSL as a single continuous layer.
Who operates there and under what rules
Class A airspace is reserved for aircraft operating under instrument flight rules (IFR) only ? this is where high-altitude airliner and business-jet traffic cruises, coordinated entirely through air traffic control clearances. Aircraft operating in Class A must be equipped with an operating transponder with automatic altitude reporting, and the pilot must hold an instrument rating. There is no visual flight rules (VFR) traffic in Class A airspace under normal circumstances.
Why Class A is not shown with boundary lines on sectional charts
Because Class A covers the entire country as one uniform layer starting at a fixed altitude, sectional charts don't depict it with a boundary line the way they show the edges of Class B, C, D, or E surface areas ? there's no boundary to draw, since it applies everywhere above 18,000 feet MSL. This is a useful fact to remember specifically because it explains an otherwise-confusing gap on the chart-reading skills covered in Module 4: you won't find a labeled Class A boundary because none exists to depict.
Why Class A is effectively irrelevant to standard Part 107 operations
The standard Part 107 altitude limit is 400 feet AGL (with the structure exception covered in Module 2 allowing somewhat higher altitude near tall structures) ? nowhere close to the 18,000-foot MSL floor where Class A begins. There is also no realistic waiver pathway that would change this: the structure exception itself is capped relative to a structure's height, and no combination of Part 107 provisions contemplates sUAS operations anywhere near flight-level altitudes. For every practical purpose, a standard Part 107 remote pilot will never need to consider Class A airspace when planning a flight.
Real-world context: why it's still worth knowing
Even though Class A never directly affects a Part 107 flight, understanding it completes the picture of how the National Airspace System is structured from the ground up ? knowledge the ACS tests directly under Area of Operation II. It also reinforces situational awareness about the broader aviation environment a remote pilot operates within: airliners cruising in Class A far overhead are simply part of the same overall system, even though their operations and a typical rooftop inspection flight never come anywhere close to intersecting.
| Attribute | Value | Relevance to Part 107 |
|---|---|---|
| Floor | 18,000 ft MSL | Far above the 400 ft AGL sUAS ceiling |
| Ceiling | FL600 (60,000 ft MSL) | Not applicable |
| Flight rules | IFR only | sUAS does not operate under IFR |
| Chart depiction | No boundary line shown | Uniform nationwide layer, nothing to depict |
| 107.41 authorization | Not applicable | sUAS operations cannot practically reach this altitude |
Why doesn't a sectional chart show a boundary line for Class A airspace?
Because Class A applies uniformly across the entire country starting at 18,000 feet MSL ? there is no lateral boundary to depict, unlike Class B, C, or D, which are located around specific airports.
Can a Part 107 waiver ever authorize flight in Class A airspace?
Not in any practical sense. The Part 107 altitude framework, including the structure exception, does not contemplate operations anywhere near the 18,000-foot MSL floor of Class A.
Why does the ACS test Class A knowledge if it never affects a real Part 107 flight?
Understanding the complete structure of the National Airspace System, including the airspace a remote pilot will never personally operate in, is part of building full situational awareness about the aviation environment ? tested directly under ACS Area of Operation II.
Test Your Knowledge
Answer the questions below to check your understanding. Every answer can be found in the lesson above.