Definition
The section of Title 14 of the Code of Federal Regulations that governs flight operations within Class D airspace. It sets the rules pilots must follow when operating in or near an airport with an operating control tower in Class D, including requirements for two-way radio communication, arrival and departure procedures, traffic pattern compliance, and minimum altitudes.
Plain English
This is the federal rule that tells pilots how to fly in and out of airports that have a control tower but aren't busy enough to be Class B or C. It covers things like talking to the tower before you enter the airspace, following the traffic pattern, and respecting minimum altitudes near the airport.
Context Anchor
Seen in AIM and regulation references when discussing operations at towered airports, especially entering Class D airspace, receiving tower instructions, taking off, or landing.
Derivation
CFR' stands for Code of Federal Regulations -- the official collection of rules issued by U.S. federal agencies. 'Title 14' is the section of that code dealing with aeronautics and space, and within it, 'Part 91' covers general operating and flight rules. 'Section 91.129' is one specific rule inside Part 91. Knowing this structure helps you find any FAR quickly: title, part, section.
Why Pilots Care
Compliance keeps traffic orderly at busy airports and avoids enforcement action for failing to follow tower instructions.
Intuition Check
Do not treat 14 CFR section 91.129 as just a handbook reference. It is a federal rule pilots are required to follow.
Example Sentence 1
Before entering the Class D airspace, the instructor reminded the student that 14 CFR section 91.129 requires two-way radio communication with the tower.
Example Sentence 2
During the checkride the examiner asked how 14 CFR section 91.129 applies to a full-stop landing at a controlled airport.