Definition
The section of the U.S. federal aviation regulations that sets the airworthiness standards for aircraft engines. It specifies the design, construction, performance, and testing requirements an engine must meet before it can be type certificated for use in civil aircraft.
Plain English
It is the rulebook the FAA uses to decide whether an aircraft engine is safe and well-built enough to be approved for use.
Context Anchor
Seen in aircraft certification and airworthiness discussions, especially when explaining how engines are approved separately from the aircraft itself.
Derivation
CFR stands for Code of Federal Regulations, the official collection of U.S. government rules. Title 14 covers Aeronautics and Space, and within it each 'part' groups rules for one topic. Part 33 is the part dedicated to aircraft engines.
Why Pilots Care
Engines must meet these standards for the aircraft to be legally airworthy and for pilots to operate with confidence in engine reliability.
Intuition Check
Do not read “part 33” as a component or physical part of the engine. Here, “part” means a numbered section of federal regulations.
Example Sentence 1
The new turboprop engine had to pass a series of endurance and vibration tests under 14 CFR part 33 before receiving its type certificate.
Example Sentence 2
Chapter 3 notes that compliance with 14 CFR Part 33 is one of the steps required before an aircraft receives its airworthiness certificate.