[Summary] Airport & Airspace Letter codes

We’ve all seen it. When you click on an airport you see the basic information, along with the “Class” followed by some weird word. What does it mean? Well, ill tell you today!

This is actually called Airspace Classes. They’re used to divide airports into certain classes and display airport restrictions. Here is a breef summary of the USA airspace classes:

Class Alpha
Airports that are in between the altitudes of 18,000 ft and 60,000 ft are classified as class A or Alpha Airports over the altitude of 60,000 ft revert to class E or Echo

Class Bravo
Class Bravo airports and airspace are major airports that are controlled by ATC. The roofing of Class B or Bravo are around 10,000 ft. In Denver, CO and Salt Lake City, UT the roofing is at 12,000 ft. In Phoenix, AZ, the roofing is at 9,000 ft. Aircraft must establish two-way radio communication with ATC and obtain a clearance to enter Class B airspace

Class Charlie
Class C or Charlie is an airspace controlled by ATC with a moderate amount of traffic.

Class Delta
Class D or Delta is an airspace with smaller amounts of traffic. The USA modified class D so that pilots only need to be in contact with ATC to enter the airspace, instead of needing clearance.

Class Echo
Class E or Echo is any other uncontrolled airspace, which always uses a Unicom. Class E airspace exists in many forms, however class E airspace rarely have traffic. It can serve as a surface-based extension to Class D airspace to accommodate IFR approach/departure procedure areas. At an altitude of over 18,000 ft, the airspace turns into class A. If over 60,000 ft, the airspace reverts back to class E

Class Foxtrot
The USA currently doesn’t have a class F or Foxtrot airspace.

Class Golf
Class G or Golf is an uncontrolled airspace, mostly used as a small airspace close to the ground.

This concludes all the Letter classes for the USA. If i have gotten any information wrong, feel free to call that out and correct me.


I’d check some of your definitions.

It’s a “Class Alpha” airspace - there is no such thing in FAA terminology as a Class Alpha Airport. It’s simply IFR airspace, where most aircraft will be in their cruise stage of flight. (Between FL180 & FL600)


Class Echo airports are uncontrolled in the sense that there is often no Air Traffic Controller present, and instead a “Unicom” frequency is used. VFR traffic can come and go as it pleases, however IFR traffic will still need clearances by ATC for the rest of their route using Class Alpha airspace.


Also a duplicate: Airspace Tiers

We have a lot of topics that have detailed a lot of various aspects in aviation so far. Seeing that this is your 4th topic within the last 24 hours, its looking like you’re simply creating topics just because or if you’re trying to level up your Trust Level. I’m not sure if that’s the intention, but the other topics “Landing gear, Spoilers, & Flaps” are basic items that folks can easily Google for themselves.