FAR 91.515 — Flight Altitude Rules

FAR 91.515 sets minimum flight altitudes for large and turbine-powered multiengine airplanes operating under VFR. It overrides the general minimum safe altitude rule in §91.119 with stricter limits.

Under VFR, you may not operate below:

• Day operations: 1,000 feet above the surface, or 1,000 feet from any mountain, hill, or other obstruction to flight.
• Night operations: the altitudes prescribed in §91.177 (the IFR minimum altitude rules).

These minimums do not apply:

• During takeoff or landing;
• When a different altitude is authorized by waiver under subpart J; or
• When the flight is conducted under special VFR minimums of §91.157 with an appropriate ATC clearance.

Why it matters: large and turbine aircraft carry more energy, descend faster, and operate at higher speeds, so the FAA requires a larger buffer above terrain and obstacles than for small piston aircraft. Knowing this rule is essential for pilots transitioning to turbine equipment.