14 CFR 29.931 - Shafting critical speed.

§ 29.931 Shafting critical speed.

(a) The critical speeds of any shafting must be determined by demonstration except that analytical methods may be used if reliable methods of analysis are available for the particular design.

(b) If any critical speed lies within, or close to, the operating ranges for idling, power-on, and autorotative conditions, the stresses occurring at that speed must be within safe limits. This must be shown by tests.

(c) If analytical methods are used and show that no critical speed lies within the permissible operating ranges, the margins between the calculated critical speeds and the limits of the allowable operating ranges must be adequate to allow for possible variations between the computed and actual values.

[Amdt. 29-12, 41 FR 55472, Dec. 20, 1976]

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

Title 14 published on 13-Apr-2017 04:10

The following are ALL rules, proposed rules, and notices (chronologically) published in the Federal Register relating to 14 CFR Part 29 after this date.

  • 2017-02-08; vol. 82 # 25 - Wednesday, February 8, 2017
    1. 82 FR 9677 - Revisions to Operational Requirements for the Use of Enhanced Flight Vision Systems (EFVS) and to Pilot Compartment View Requirements for Vision Systems
      GPO FDSys XML | Text
      DEPARTMENT OF TRANSPORTATION, Federal Aviation Administration
      Final rule; delay of effective date.
      The effective date of the rule amending 14 CFR parts 1, 23, 25, 27, 29, 61, 91, 121, 125, and 135 published at 81 FR 90126, December 13, 2016, is delayed until March 21, 2017, except for the amendments to §§ 61.66 (amendatory instruction no. 15), 91.175 (amendatory instruction no. 18), 91.1039 (amendatory instruction no. 23), 121.651 (amendatory instruction no. 27), 125.325 (amendatory instruction no. 33), 125.381 (amendatory instruction no. 35), and 135.225 (amendatory instruction no. 38), which are effective March 13, 2018.
      14 CFR Parts 1, 23, 25, 27, 29, 61, 91, 121, 125, and 135