FAR/AIM: Section 3. Class G Airspace

Class G airspace (uncontrolled) is that portion of airspace that has not been designated as Class A, Class B, Class C, Class D, or Class E airspace.

Rules governing VFR flight have been adopted to assist the pilot in meeting the responsibility to see and avoid other aircraft. Minimum flight visibility and distance from clouds required for VFR flight are contained in 14 CFR Section 91.155. (See TBL 3-1-1.)

1. Title 14 CFR specifies the pilot and aircraft equipment requirements for IFR flight. Pilots are reminded that in addition to altitude or flight level requirements, 14 CFR Section 91.177 includes a requirement to remain at least 1,000 feet (2,000 feet in designated mountainous terrain) above the highest obstacle within a horizontal distance of 4 nautical miles from the course to be flown.
2. IFR Altitudes. (See TBL 3-3-1.)

   TBL 3-3-1
   IFR Altitudes Class G Airspace

   If your magnetic course (ground track) is:	And you are below 18,000 feet MSL, fly:
   0° to 179°	Odd thousands MSL, (3,000; 5,000; 7,000, etc.)
   180° to 359°	Even thousands MSL, (2,000; 4,000; 6,000, etc.)