Definition
A subsection of Title 14 of the Code of Federal Regulations, Part 61, that sets the additional training and endorsement requirements a pilot must meet before acting as pilot in command of a complex airplane — that is, an airplane with retractable landing gear, flaps, and a controllable-pitch propeller (or, for seaplanes, flaps and a controllable-pitch propeller).
Plain English
A specific FAA rule that says: before you can fly a more advanced airplane on your own, you must get ground and flight training from an instructor and a logbook endorsement saying you are competent to fly that type of airplane.
Context Anchor
You will see this citation in FAA training material when commercial pilot training, complex airplanes, and required endorsements are being discussed.
Derivation
Section comes from a Latin word meaning “to cut.” In regulations, a section is one cut-out, numbered part of the rules. The citation 61.31(e) works like a legal address: Part 61, section 31, paragraph (e).
Why Pilots Care
Compliance ensures the pilot has demonstrated the knowledge and skills needed to operate high-performance aircraft safely and legally.
Analogy
Think of section 61.31(e) like an address in a rulebook. It does not explain the whole subject by itself; it tells you exactly where to find the controlling rule.
Intuition Check
Do not read “section” here as a section of the handbook. Section 61.31(e) points to a specific paragraph in the federal aviation regulations.
Example Sentence 1
Before her first solo flight in the Arrow, she received the section 61.31(e) endorsement from her instructor.
Example Sentence 2
Section 61.31(e) training includes both ground instruction on systems and flight maneuvers specific to high-performance airplanes.