14 CFR 33.94 - Blade containment and rotor unbalance tests.

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There are 2 Updates appearing in the Federal Register for 14 CFR 33. View below or at eCFR (GPOAccess)
§ 33.94 Blade containment and rotor unbalance tests.
(a) Except as provided in paragraph (b) of this section, it must be demonstrated by engine tests that the engine is capable of containing damage without catching fire and without failure of its mounting attachments when operated for at least 15 seconds, unless the resulting engine damage induces a self shutdown, after each of the following events:
(1) Failure of the most critical compressor or fan blade while operating at maximum permissible r.p.m. The blade failure must occur at the outermost retention groove or, for integrally-bladed rotor discs, at least 80 percent of the blade must fail.
(2) Failure of the most critical turbine blade while operating at maximum permissible r.p.m. The blade failure must occur at the outermost retention groove or, for integrally-bladed rotor discs, at least 80 percent of the blade must fail. The most critical turbine blade must be determined by considering turbine blade weight and the strength of the adjacent turbine case at case temperatures and pressures associated with operation at maximum permissible r.p.m.
(b) Analysis based on rig testing, component testing, or service experience may be substitute for one of the engine tests prescribed in paragraphs (a)(1) and (a)(2) of this section if—
(1) That test, of the two prescribed, produces the least rotor unbalance; and
(2) The analysis is shown to be equivalent to the test.
(Secs. 313(a), 601, and 603, Federal Aviation Act of 1958 (49 U.S.C. 1354(a), 1421, and 1423); and 49 U.S.C. 106(g) Revised, Pub. L. 97-449, Jan. 12, 1983)
[Amdt. 33-10, 49 FR 6854, Feb. 23, 1984]

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.

  • 2014-11-04; vol. 79 # 213 - Tuesday, November 4, 2014
    1. 79 FR 65508 - Airplane and Engine Certification Requirements in Supercooled Large Drop, Mixed Phase, and Ice Crystal Icing Conditions
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      DEPARTMENT OF TRANSPORTATION, Federal Aviation Administration
      Final rule.
      Effective January 5, 2015.
      14 CFR Parts 25 and 33

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United States Code

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 33 after this date.

  • 2014-11-14; vol. 79 # 220 - Friday, November 14, 2014
    1. 79 FR 68137 - Special Conditions: CFM International, LEAP-1A and -1C Engine Models; Incorporation of Woven Composite Fan Blades
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      DEPARTMENT OF TRANSPORTATION, Federal Aviation Administration
      Notice of proposed special conditions.
      Send your comments on or before December 29, 2014.
      14 CFR Part 33