Definition
The section of federal aviation regulations that establishes standards for determining whether an object on the ground is an obstruction to air navigation, sets requirements for notifying the FAA of proposed construction or alteration that may affect navigable airspace, and defines the imaginary surfaces around airports used to evaluate obstruction hazards.
Plain English
A federal rule that decides when a tower, building, crane, or other tall object is tall enough or close enough to an airport to be considered a hazard to aircraft, and requires people to tell the FAA before building it.
Context Anchor
You may see 14 CFR part 77 mentioned in discussions of obstructions, airport planning, runway approaches, construction near airports, and FAA airspace studies.
Derivation
CFR stands for Code of Federal Regulations, the official collection of US federal rules. Title 14 covers Aeronautics and Space, and Part 77 is the specific part within it that deals with objects affecting navigable airspace.
Why Pilots Care
These regulations protect the airspace surfaces around airports, ensuring new structures do not penetrate protected areas and create collision risks or force changes to approach and departure procedures.
Intuition Check
Do not read “part 77” as a physical airplane part or a section of the AIM. Here, it means a specific numbered federal aviation regulation.
Example Sentence 1
Before the developer could break ground on the new tower near the airport, they had to file a 14 CFR part 77 notice with the FAA.
Example Sentence 2
The FAA determined under 14 CFR part 77 that the proposed wind turbines would not penetrate the obstacle clearance surface.