14 CFR 91.179 - IFR cruising altitude or flight level.

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There are 10 Updates appearing in the Federal Register for 14 CFR 91. View below or at eCFR (GPOAccess)
§ 91.179 IFR cruising altitude or flight level.
Unless otherwise authorized by ATC, the following rules apply—
(a) In controlled airspace. Each person operating an aircraft under IFR in level cruising flight in controlled airspace shall maintain the altitude or flight level assigned that aircraft by ATC. However, if the ATC clearance assigns “VFR conditions on-top,” that person shall maintain an altitude or flight level as prescribed by § 91.159.
(b) In uncontrolled airspace. Except while in a holding pattern of 2 minutes or less or while turning, each person operating an aircraft under IFR in level cruising flight in uncontrolled airspace shall maintain an appropriate altitude as follows:
(1) When operating below 18,000 feet MSL and—
(i) On a magnetic course of zero degrees through 179 degrees, any odd thousand foot MSL altitude (such as 3,000, 5,000, or 7,000); or
(ii) On a magnetic course of 180 degrees through 359 degrees, any even thousand foot MSL altitude (such as 2,000, 4,000, or 6,000).
(2) When operating at or above 18,000 feet MSL but below flight level 290, and—
(i) On a magnetic course of zero degrees through 179 degrees, any odd flight level (such as 190, 210, or 230); or
(ii) On a magnetic course of 180 degrees through 359 degrees, any even flight level (such as 180, 200, or 220).
(3) When operating at flight level 290 and above in non-RVSM airspace, and—
(i) On a magnetic course of zero degrees through 179 degrees, any flight level, at 4,000-foot intervals, beginning at and including flight level 290 (such as flight level 290, 330, or 370); or
(ii) On a magnetic course of 180 degrees through 359 degrees, any flight level, at 4,000-foot intervals, beginning at and including flight level 310 (such as flight level 310, 350, or 390).
(4) When operating at flight level 290 and above in airspace designated as Reduced Vertical Separation Minimum (RVSM) airspace and—
(i) On a magnetic course of zero degrees through 179 degrees, any odd flight level, at 2,000-foot intervals beginning at and including flight level 290 (such as flight level 290, 310, 330, 350, 370, 390, 410); or
(ii) On a magnetic course of 180 degrees through 359 degrees, any even flight level, at 2000-foot intervals beginning at and including flight level 300 (such as 300, 320, 340, 360, 380, 400).
[Doc. No. 18334, 54 FR 34294, Aug. 18, 1989, as amended by Amdt. 91-276, 68 FR 61321, Oct. 27, 2003; 68 FR 70133, Dec. 17, 2003; Amdt. 91-296, 72 FR 31679, June 7, 2007]

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.

  • 2014-07-25; vol. 79 # 143 - Friday, July 25, 2014
    1. 79 FR 43240 - Interpretation of the Special Rule for Model Aircraft
      GPO FDSys XML | Text
      DEPARTMENT OF TRANSPORTATION, Federal Aviation Administration
      Notice of interpretation with request for comment; Extension of comment period.
      The comment period for the notice of interpretation published June 25, 2014 (79 FR 36172), is extended. Comments must be received on or before September 23, 2014.
      14 CFR Part 91

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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.

  • 2014-07-25; vol. 79 # 143 - Friday, July 25, 2014
    1. 79 FR 43240 - Interpretation of the Special Rule for Model Aircraft
      GPO FDSys XML | Text
      DEPARTMENT OF TRANSPORTATION, Federal Aviation Administration
      Notice of interpretation with request for comment; Extension of comment period.
      The comment period for the notice of interpretation published June 25, 2014 (79 FR 36172), is extended. Comments must be received on or before September 23, 2014.
      14 CFR Part 91