AIM Text
- When overlapping airspace designations apply to the same airspace, the operating rules associated with the more restrictive airspace designation apply.
- For the purpose of clarification:
- Class A airspace is more restrictive than Class B, Class C, Class D, Class E, or Class G airspace;
- Class B airspace is more restrictive than Class C, Class D, Class E, or Class G airspace;
- Class C airspace is more restrictive than Class D, Class E, or Class G airspace;
- Class D airspace is more restrictive than Class E or Class G airspace; and
- Class E is more restrictive than Class G airspace.
Source: FAA Aeronautical Information Manual · current edition · paragraph 3-1-3.
The short answer
This AIM section provides FAA advisory guidance on overlapping airspace: when designations overlap the same airspace, the operating rules of the more restrictive designation apply. It ranks restrictiveness from Class A (most) down through B, C, D, E, to G, helping pilots determine which rules govern, supporting the VFR weather minimums of 14 CFR 91.155.
Research Notes
Common Questions
Which rules apply when two airspace classes overlap?
Per this AIM section, when overlapping airspace designations apply to the same airspace, the operating rules associated with the more restrictive airspace designation apply.
Is Class C more restrictive than Class D?
Yes. The AIM ranks Class C as more restrictive than Class D, Class E, or Class G airspace. The full order is A more restrictive than B, B than C, C than D, D than E, and E than G.
When is the ceiling too low for basic VFR near a surface-area airport?
The AIM (in the adjoining VFR minimums guidance) notes that, except under Special VFR per 14 CFR 91.157, no person may operate beneath the ceiling under VFR within controlled airspace designated to the surface for an airport when the ceiling is less than 1,000 feet (see 14 CFR 91.155(c)).