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Part 91
Title 14 CFR Part 91 — the FAA regulation covering general operating and flight rules for all aircraft operations in U.S. airspace. Part 91 defines rules for VFR/IFR flight, equipment requirements, maintenance responsibilities, and pilot-in-command authority.
Related Terms
- Personal MinimumsPilot-specific limits that are more restrictive than legal weather, altitude, or aircraft limits — such as ceiling, visibility, crosswind, fuel reserves, or an oxygen-use altitude. Written personal minimums keep go/no-go and equipment decisions consistent under schedule or passenger pressure.
- PIC (Pilot in Command)The pilot designated as the final authority and directly responsible for the operation and safety of the flight. The PIC has the authority to deviate from any rule in an emergency to the extent required to meet the emergency.
- PIREP (Pilot Weather Report)An observation of weather conditions reported by a pilot in flight. PIREPs describe conditions such as turbulence, icing, cloud bases and tops, visibility, and wind shear, giving other pilots timely evidence to compare against forecasts.
- Pitot-Static SystemThe system of pressure-sensing instruments that includes the airspeed indicator, altimeter, and vertical speed indicator. It works by comparing ram air pressure (from the pitot tube) with static atmospheric pressure (from static ports).