Aircraft Speed Limits
CFR, Part 91, imposes the following maximum airspeed limitations:
1. Unless otherwise authorized by the Administrator, no person may operate an
aircraft below 10,000 feet mean sea level (MSL) at an indicated airspeed of more
than 250 knots.
2. Unless otherwise authorized or required by ATC, no person may operate an
aircraft at or below 2,500 feet above the surface within 4 nautical miles of the
primary airport of a Class C or Class D airspace area at an indicated airspeed of
more than 200 knots. This does not apply to any operations within a Class B
airspace area.
3. No person may operate an aircraft in the airspace underlying a Class B airspace
area designated for an airport, or in a VFR corridor designated through such a
Class B airspace area, at an indicated airspeed of more than 200 knots.
4. If the minimum safe airspeed for any particular operation is greater than the
maximum speed, the aircraft may be operated at that minimum speed.
Exceptions to Aircraft Speed Limits
The regulation grants exception for operations that cannot safely be conducted at
airspeeds less than the prescribed maximum airspeed. For example, the FAA has
authorized the Department of Defense (DOD) to exceed 250 knots indicated airspeed
(KIAS) below 10,000 feet MSL for operations within restricted areas or military
operations areas and on mutually developed and published routes such as military
training routes.
If the airspeed required or recommended in the aircraft NATOPS manual for maintaining
safe maneuverability is greater than the maximum speeds, the aircraft may be operated
at that speed. However, the pilot must notify the air traffic control facility (ATCF) of that
higher speed.
Minimum Safe Altitudes
Except when necessary for takeoff or landing, no person may operate an aircraft below
the following altitudes, expressed by region:
1. Anywhere An altitude allowing, if a power unit fails, an emergency landing
without undue hazard to persons or property on the surface
2. Over congested areas Over any congested area of a city, town, or settlement,
or over any open air assembly of persons, an altitude of 1,000 feet above the
highest obstacle within a horizontal radius of 2,000 feet of the aircraft
3. Over other-than-congested areas An altitude of 500 feet above the surface,
except over open water or sparsely populated areas. In those cases, the aircraft
may not be operated closer than 500 feet to any person, vessel, vehicle, or
structure.
Helicopters, powered parachutes, and weight-shift-control aircraft. If the operation is
conducted without hazard to persons or property on the surface:
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