Airspace Classes | A FREE Resource to Master Airspace.
Students struggle with the interpretation of airspace classes all the time. For that reason, airspace is a big segment in our live CFI Ground School. We’ve created this FREE resource combined with the “must knows” to help you fully understand and gain confidence with interpreting airspace on aeronautical charts.
The components involved with airspaces include the:
Location of an aircraft.
The area found on a sectional chart.
The controlling agency that is responsible for that area (ATC) if applicable.
Within these defined areas, and depending on the class of airspace, it is expected that certain rules apply - such as:
How far we should be able to see outside from our cockpit.
Resources ATC can provide such as aircraft separation and traffic advisories.
As a general rule, legally under VFR you are able to see outside no less than 3 SM, keep the aircraft at least 1000' above, 2000' away from the sides, and no higher than 500' below clouds (3152). Even though these are the legal requirements.
As a baseline when discussing airspace, we begin with Class Delta. This is where the majority of pilots begin flight training. An emphasis on communication must be established while learning about class D airspace.
Students must be trained to be clear, concise, and specific with intentions and requests. This is the beginning stages of dialogue, and applies to all other airspaces.
Since the topic of communication is vital when a controlling agency is present (ATC), such as in Class D airspaces, any aircraft that wants to enter must get that controlling agency to be aware of their existence. Establishing communications between the control tower and the pilot is required in class D airspace.
Class D: "Dialogue" - Talk to the tower!
As a general rule of thumb and space permitting, this airspace's dimensions typically extend from the surface to 2,500 feet (MSL) above and 4 NM radius from the runway. If anyone wishes to be the sole operator of an aircraft here, the bare minimum certificate is at least a Student Pilot license, and as discussed earlier, adheres to the minimum flight visibility of "3152".
The primary priority of ATC here is to separate aircraft on their active runways, but since most training flight schools operate out of airports located here, traffic advisories and aircraft separation to assist with students training are only given if ATC workload permits.
Class Charlie airspace builds on this by adding another layer on top to accommodate incoming airplanes with passengers on instrument flight plans.
Class C: "Crowded" - talk to approach control.
Airspace dimensions here usually extend from the surface to 4,000 feet (MSL) with a 5 NM radius, and the added layer on top that spans up to 10 NM radius (1,200 ft. to 4,000 ft.) above the airport's elevation. A Student Pilot license and a visibility condition of 3152 is still the minimum, but establishing communications with the controlling agency before entering either of the layers is crucial because of all the congested activity going on.
The priority of ATC is to prioritize separation of only IFR aircraft. In doing so, this is the first area in our progression of airspaces where the transponder becomes a required equipment to operate with -- a device that provides identification of our aircraft for ATC's radars.
Class Bravo is even bigger, and with dimensions that are individually tailored according to the local terrain and instrument approaches of the area, but generally extend from the surface to 10,000 feet (MSL).
Class B: "Big" or "Busy".
Greater risks are associated with operations in class B airspace. The minimum certificate needed is now elevated to at least either a Private Pilot License, or a Student Pilot certificate with additional required endorsements. Transponder identification is needed in class b airspace. Any aircraft operating under VFR must receive an explicit ATC clearance before crossing into Bravo airspace.
The minimum legal visibility condition is 3 SM, but since all aircraft operating within Class B are now under separation services from ATC, cloud clearances are now loosened. ATC is able to provide help for separation of aircraft in this airspace.
Class Alpha airspace is an area where most general aviation is excluded, unless operating under IFR and flying above 18,000 ft. to 60,000 ft. Since ATC clearance is required here, this is when ATC is relied on for specific instructions.
Class A: "Altitude" since it involves> 18,000 ft. MSL
The airspace in between Delta, Charlie, Bravo, and below Alpha is all defined as Class Echo airspace, where it either begins from either the surface, 700 ft. or 1,200 ft. AGL (if not depicted on a chart, at 14,500 ft. MSL) up to but not including 18,000 ft. MSL.
A large amount of our airspace is defined as this, and exists solely to provide safe operation and separation of aircraft operating under IFR operations.
This typically is a rundown of the airspaces we encounter in the general world of GA aircraft, that operate under VFR operations with low service ceilings. Even though certain regulations are listed out in Part 91.
Class E: "Everything Else"
For both Class E and Class G airspace, at altitudes of above 10,000 ft. MSL, the visibility requirements are more restrictive and need a minimum visibility of 5 SM, still remaining 1000 ft. above, but now needing to be 1000 ft. below, and more restrictive 1 SM cloud clearance. A transponder also becomes required at these altitudes.
Class G: "Go for it!"
IFR and VFR flight are permitted. There are no communications, or. transponder requirements. Pilots may operate freely without clearnace or establishing two-way communications with ATC.