Definition
A specific paragraph within Title 14 of the Code of Federal Regulations, Part 23 (Airworthiness Standards: Normal Category Airplanes), which sets out one of the conditions used to establish the minimum control speed (VMC) for multi-engine airplanes. Specifically, 14 CFR 23.149(b)(1) requires that VMC be determined with the airplane in the most critical takeoff configuration, with the critical engine suddenly made inoperative, and the rudder force used to maintain straight flight not exceeding 150 pounds.
Plain English
It is a federal rule that tells manufacturers exactly how to find the slowest speed at which a twin-engine airplane can still be controlled after one engine quits. The rule sets the conditions for the test, including a limit of 150 pounds of rudder pedal force.
Context Anchor
Seen in multiengine training when explaining how published VMC is determined during airplane certification.
Derivation
The numbering comes from the U.S. Code of Federal Regulations: Title 14 (aviation), Part 23 (small airplane airworthiness), Section 149 (the section covering minimum control speed). The (b)(1) points to a specific subparagraph within that section. Knowing this helps because pilots often see the citation alone and may not realize it is simply an address pointing to a paragraph in the rulebook.
Why Pilots Care
It explains the certified limits of directional control when an engine fails, directly affecting safe single-engine operations and published speeds in the pilot's operating handbook.
Intuition Check
Do not read “section” here as a section of the airplane or just a page heading. It is a precise legal reference to one numbered part of an FAA rule.
Example Sentence 1
The instructor explained that the VMC marked on the airspeed indicator was determined under the conditions laid out in section 23.149(b)(1).
Example Sentence 2
During engine-out training the instructor reminded the student that section 23.149(b)(1) sets the regulatory baseline for the speeds shown on the airspeed indicator.