Federal Aviation Regulations
14 CFR § 91.117 — Aircraft speed
Volume 2 · Title 14 of the Code of Federal Regulations, 2025 annual edition. U.S. Government work — public domain (17 U.S.C. §105).
The regulation, in full
Sec. 91.117 Aircraft speed.
(a) Unless otherwise authorized by the Administrator, no person may
operate an aircraft below 10,000 feet MSL at an indicated airspeed of
more than 250 knots (288 m.p.h.).
(b) 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 (230 mph.). This
paragraph (b) does not apply to any operations within a Class B airspace
area. Such operations shall comply with paragraph (a) of this section.
(c) 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 (230 mph).
(d) If the minimum safe airspeed for any particular operation is
greater than the maximum speed prescribed in this section, the aircraft
may be operated at that minimum speed.
[Docket 18334, 54 FR 34292, Aug. 18, 1989, as amended by Amdt. 91-219,
55 FR 34708, Aug. 24, 1990; Amdt. 91-227, 56 FR 65657, Dec. 17, 1991;
Amdt. 91-233, 58 FR 43554, Aug. 17, 1993]What this means for the knowledge test
Our own study notes for this section — reviewed through our AI instructional-review system, not by a certificated flight instructor. Not an authoritative source.
Below 10,000 feet MSL an aircraft may not exceed 250 knots indicated airspeed. Within Class C or Class D airspace at or below 2,500 feet AGL within 4 nautical miles of the primary airport, the limit is 200 knots. Below a Class B shelf or in a VFR corridor through Class B, the limit is also 200 knots.
14 CFR 91.117
Lessons that cover § 91.117
Practice questions on § 91.117 (1)
What is the maximum indicated airspeed below 10,000 feet MSL?
Answer 250 knots
Below 10,000 feet MSL, aircraft may not exceed 250 knots indicated airspeed.