U.S. DEPARTMENT OF TRANSPORTATION
FEDERAL AVIATION ADMINISTRATION

Subject:  Procedures for Handling Airspace Matters
This Basic includes Change 1 effective 7/24/14.

Chapter 3. Aeronautical Information

Section 1. General

3-1-1. POLICY

All geographic (latitude and longitude) and vertical data submitted or used in airspace matters must be based on current North American Datum (NAD) criteria.

3-1-2. RESPONSIBILITY

a. Aeronautical Information Management (AIM) is responsible for coordination with charting agencies and chart producers.

b. AIM will furnish appropriate aeronautical chart cutoff and publication dates. Cutoff dates are 9 weeks (10 weeks for action involving flight check) in advance of the publication date to allow sufficient time for charting and chart distribution purposes.

c. Any information pertinent to the development of aeronautical information (e.g., validation of geographical coordinates, airport geographic positions, true radials, etc.) must be obtained from AIM.

3-1-3. TRUE/MAGNETIC DIRECTIONS

All radials, courses, and bearings specified in an NPRM must be stated both as true and magnetic, except magnetic need not be stated in terminal airspace notices.

3-1-4. NAVIGATIONAL AID COORDINATES

When a navigational aid (NAVAID) is used as a reference point in a controlled airspace description, its geographic coordinates must be included in degrees, minutes, and seconds.

3-1-5. DIRECTIONS

Directions must be described as follows: