14 CFR 91.121 - Altimeter settings.

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There are 11 Updates appearing in the Federal Register for 14 CFR 91. View below or at eCFR (GPOAccess)
§ 91.121 Altimeter settings.
(a) Each person operating an aircraft shall maintain the cruising altitude or flight level of that aircraft, as the case may be, by reference to an altimeter that is set, when operating—
(1) Below 18,000 feet MSL, to—
(i) The current reported altimeter setting of a station along the route and within 100 nautical miles of the aircraft;
(ii) If there is no station within the area prescribed in paragraph (a)(1)(i) of this section, the current reported altimeter setting of an appropriate available station; or
(iii) In the case of an aircraft not equipped with a radio, the elevation of the departure airport or an appropriate altimeter setting available before departure; or
(2) At or above 18,000 feet MSL, to 29.92″ Hg.
(b) The lowest usable flight level is determined by the atmospheric pressure in the area of operation as shown in the following table:
Current altimeter setting Lowest usable flight level
29.92 (or higher) 180
29.91 through 29.42 185
29.41 through 28.92 190
28.91 through 28.42 195
28.41 through 27.92 200
27.91 through 27.42 205
27.41 through 26.92 210
(c) To convert minimum altitude prescribed under §§ 91.119 and 91.177 to the minimum flight level, the pilot shall take the flight level equivalent of the minimum altitude in feet and add the appropriate number of feet specified below, according to the current reported altimeter setting:
Current altimeter setting Adjustment factor
29.92 (or higher) None
29.91 through 29.42 500
29.41 through 28.92 1,000
28.91 through 28.42 1,500
28.41 through 27.92 2,000
27.91 through 27.42 2,500
27.41 through 26.92 3,000

Title 14 published on 2014-01-01

The following are only the Rules published in the Federal Register after the published date of Title 14.

For a complete list of all Rules, Proposed Rules, and Notices view the Rulemaking tab.

  • 2014-09-25; vol. 79 # 186 - Thursday, September 25, 2014
    1. 79 FR 57431 - Airports/Locations: Special Operating Restrictions
      GPO FDSys XML | Text
      DEPARTMENT OF TRANSPORTATION, Federal Aviation Administration
      Final rule; technical amendment.
      Effective Date: November 13, 2014.
      14 CFR Part 91

This is a list of United States Code sections, Statutes at Large, Public Laws, and Presidential Documents, which provide rulemaking authority for this CFR Part.

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United States Code
U.S. Code: Title 49 - TRANSPORTATION

§ 106 - Federal Aviation Administration

§ 1155 - Aviation penalties

§ 40103 - Sovereignty and use of airspace

§ 40113 - Administrative

§ 40120 - Relationship to other laws

§ 44101 - Operation of aircraft

§ 44111 - Modifications in registration and recordation system for aircraft not providing air transportation

§ 44701 - General requirements

§ 44704 - Type certificates, production certificates, airworthiness certificates,,

§ 44709 - Amendments, modifications, suspensions, and revocations of certificates

§ 44711 - Prohibitions and exemption

§ 44712 - Emergency locator transmitters

§ 44715 - Controlling aircraft noise and sonic boom

§ 44716 - Collision avoidance systems

§ 44717 - Aging aircraft

§ 44722 - Aircraft operations in winter conditions

§ 46306 - Registration violations involving aircraft not providing air transportation

§ 46315 - Lighting violations involving transporting controlled substances by aircraft not providing air transportation

§ 46316 - General criminal penalty when specific penalty not provided

§ 46504 - Interference with flight crew members and attendants

§ 46506 - Application of certain criminal laws to acts on aircraft

§ 46507 - False information and threats

§ 47122 - Administrative

§ 47508 - Noise standards for air carriers and foreign air carriers providing foreign air transportation

§ 47528 - Prohibition on operating certain aircraft not complying with stage 3 noise levels

§ 47529 - Nonaddition rule

§ 47530 - Nonapplication of

§ 47531 - Penalties

§ 47534 - Prohibition on operating certain aircraft weighing 75,000 pounds or less not complying with stage 3 noise levels

Statutes at Large

Title 14 published on 2014-01-01

The following are ALL rules, proposed rules, and notices (chronologically) published in the Federal Register relating to 14 CFR 91 after this date.

  • 2014-09-25; vol. 79 # 186 - Thursday, September 25, 2014
    1. 79 FR 57431 - Airports/Locations: Special Operating Restrictions
      GPO FDSys XML | Text
      DEPARTMENT OF TRANSPORTATION, Federal Aviation Administration
      Final rule; technical amendment.
      Effective Date: November 13, 2014.
      14 CFR Part 91