Definition
The section of the Federal Aviation Regulations that lists the minimum instruments and equipment required for an airplane to be operated under instrument flight rules (IFR). It builds on the day-VFR and night-VFR equipment lists by adding items needed for flight in instrument meteorological conditions, such as a two-way radio and navigation equipment suitable for the route, a gyroscopic rate-of-turn indicator, slip-skid indicator, sensitive altimeter adjustable for barometric pressure, generator or alternator of adequate capacity, gyroscopic pitch and bank indicator (attitude indicator), and gyroscopic direction indicator (heading indicator or equivalent).
Plain English
This is the FAA rule that lists what working instruments and equipment an airplane must have on board before it can legally fly under instrument flight rules. If something on this list is missing or broken, the airplane cannot be flown IFR until it is fixed or properly addressed.
Context Anchor
You will see this citation when checking whether an airplane is legal for night VFR flight, especially in equipment, lighting, and preflight planning discussions.
Derivation
CFR stands for Code of Federal Regulations, the official collection of U.S. federal rules. Title 14 covers Aeronautics and Space, part 91 covers general operating and flight rules, section 91.205 lists required instruments and equipment, and paragraph (d) is the IFR-specific subsection. The numbering is a precise address: title, part, section, paragraph.
Why Pilots Care
Compliance confirms the aircraft meets legal requirements for safe IFR flight, directly affecting whether the pilot can accept an IFR clearance or continue into instrument conditions without violating regulations.
Intuition Check
“Part” and “section” here do not mean a physical airplane part or a chapter section in a textbook. They identify an exact location in the FAA regulations.
Example Sentence 1
During preflight, the pilot reviewed 14 CFR part 91 section 91.205(d) and verified that the attitude indicator, heading indicator, and rate-of-turn indicator were all functioning before filing IFR.
Example Sentence 2
During the annual inspection review, the mechanic verified that all items listed in 14 CFR part 91 section 91.205(d) were present and serviceable.