Definition
A specific paragraph of the Federal Aviation Regulations that allows a pilot receiving training for a type rating, additional category or class rating, or for a complex, high-performance, tailwheel, or similar aircraft endorsement to act as pilot in command of that aircraft when under the supervision of an authorized instructor, provided the aircraft is not carrying passengers and the flight is conducted in U.S. airspace.
Plain English
It is the rule that lets a student act as pilot in command of an aircraft they are not yet rated or endorsed for, but only while training with an authorized instructor and with no passengers on board.
Context Anchor
Seen in flight instructor endorsement records, logbook endorsements, and training for an added aircraft category or class rating.
Derivation
The reference reads as a regulatory address: Title 14 of the Code of Federal Regulations (the aviation title), Part 61 (certification of pilots and instructors), Section 61.31 (additional aircraft requirements), paragraph (d), subparagraph (2). Reading the address from left to right narrows from broad subject down to the specific rule.
Why Pilots Care
Operating a high-performance airplane without this endorsement violates federal regulations and can result in enforcement action or insurance denial.
Intuition Check
Do not read this citation as blanket permission to fly any unrated aircraft. In this context, it is about a limited solo training authorization after instruction and an instructor sign-off.
Example Sentence 1
The instructor signed the trainee's logbook with an endorsement citing 14 CFR part 61 section 61.31(d)(2), authorizing him to act as pilot in command of the complex airplane during dual instruction.
Example Sentence 2
Before the checkride, the student verified the endorsement met 14 CFR part 61 section 61.31(d)(2) standards.