Aeronautical Information Manual (AIM), page 147

Index   146 -- Page 147 -- 148

Chapter 3. Airspace
Section 1. General

3-1-1. General

a. There are two categories of airspace or airspace


1. Regulatory (Class A, B, C, D and E airspace
areas, restricted and prohibited areas); and

2. Nonregulatory (military operations areas
(MOAs), warning areas, alert areas, and controlled
firing areas).
Additional information on special use airspace (prohibited
areas, restricted areas, warning areas, MOAs, alert areas
and controlled firing areas) may be found in Chapter 3,
Airspace, Section 4, Special Use Airspace, para-
graphs 3-4-1 through 3-4-7.

b. Within these two categories, there are four

1. Controlled,

2. Uncontrolled,

3. Special use, and

4. Other airspace.
c. The categories and types of airspace are dictated

1. The complexity or density of aircraft

2. The nature of the operations conducted
within the airspace,

3. The level of safety required, and

4. The national and public interest.

d. It is important that pilots be familiar with the
operational requirements for each of the various types
or classes of airspace. Subsequent sections will cover
each class in sufficient detail to facilitate

3-1-2. General Dimensions of Airspace

Refer to Code of Federal Regulations (CFRs) for

specific dimensions, exceptions, geographical areas
covered, exclusions, specific transponder or equip-
ment requirements, and flight operations.

3-1-3. Hierarchy of Overlapping Airspace
a. When overlapping airspace designations apply
to the same airspace, the operating rules associated
with the more restrictive airspace designation apply.
b. For the purpose of clarification:

1. Class A airspace is more restrictive than
Class B, Class C, Class D, Class E, or Class G

2. Class B airspace is more restrictive than
Class C, Class D, Class E, or Class G airspace;
3. Class C airspace is more restrictive than
Class D, Class E, or Class G airspace;

4. Class D airspace is more restrictive than
Class E or Class G airspace; and
5. Class E is more restrictive than Class G

3-1-4. Basic VFR Weather Minimums
a. No person may operate an aircraft under basic
VFR when the flight visibility is less, or at a distance
from clouds that is less, than that prescribed for the
corresponding altitude and class of airspace.
(See TBL 3-1-1.)

Student pilots must comply with 14 CFR Section 61.89(a)

(6) and (7).
b. Except as provided in 14 CFR Section 91.157,
Special VFR Weather Minimums, no person may
operate an aircraft beneath the ceiling under VFR
within the lateral boundaries of controlled airspace
designated to the surface for an airport when the
ceiling is less than 1,000 feet. (See 14 CFR
Section 91.155(c).)

General 3-1-1

Page 147 of the Aeronautical Information Manual (AIM.pdf)
AIM: Official Guide to Basic Flight Information and ATC Procedures

Index   146 -- Page 147 -- 148