14 CFR 23.425 - Gust loads.

Beta! The text on the eCFR tab represents the unofficial eCFR text at ecfr.gov.
§ 23.425 Gust loads.

(a) Each horizontal surface, other than a main wing, must be designed for loads resulting from -

(1) Gust velocities specified in § 23.333(c) with flaps retracted; and

(2) Positive and negative gusts of 25 f.p.s. nominal intensity at V F corresponding to the flight conditions specified in § 23.345(a)(2).

(b) [Reserved]

(c) When determining the total load on the horizontal surfaces for the conditions specified in paragraph (a) of this section, the initial balancing loads for steady unaccelerated flight at the pertinent design speeds VF, VC, and VD must first be determined. The incremental load resulting from the gusts must be added to the initial balancing load to obtain the total load.

(d) In the absence of a more rational analysis, the incremental load due to the gust must be computed as follows only on airplane configurations with aft-mounted, horizontal surfaces, unless its use elsewhere is shown to be conservative:

where -
ΔLht = Incremental horizontal tailload (lbs.);
Kg = Gust alleviation factor defined in § 23.341;
Ude = Derived gust velocity (f.p.s.);
V = Airplane equivalent speed (knots);
aht = Slope of aft horizontal lift curve (per radian)
Sht = Area of aft horizontal lift surface (ft 2); and
[Doc. No. 4080, 29 FR 17955, Dec. 18, 1964, as amended by Amdt. 23-7, 34 FR 13089 Aug. 13, 1969; Amdt. 23-42, 56 FR 353, Jan. 3, 1991]

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.

This list is taken from the Parallel Table of Authorities and Rules provided by GPO [Government Printing Office].

It is not guaranteed to be accurate or up-to-date, though we do refresh the database weekly. More limitations on accuracy are described at the GPO site.

United States Code

Title 14 published on 2015-01-01

The following are ALL rules, proposed rules, and notices (chronologically) published in the Federal Register relating to 14 CFR Part 23 after this date.

  • 2015-12-09; vol. 80 # 236 - Wednesday, December 9, 2015
    1. 80 FR 76379 - Special Conditions: Cirrus Aircraft Corporation, SF50; Auto Throttle
      GPO FDSys XML | Text
      DEPARTMENT OF TRANSPORTATION, Federal Aviation Administration
      Final special conditions.
      The effective date of these special conditions is December 9, 2015 and are applicable on December 2, 2015.
      14 CFR Part 23