14 CFR § 29.175 - Demonstration of static longitudinal stability.

---
identifier: "/us/cfr/t14/s29.175"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "14 CFR § 29.175 - Demonstration of static longitudinal stability."
title_number: 14
title_name: "Aeronautics and Space"
section_number: "29.175"
section_name: "Demonstration of static longitudinal stability."
chapter_name: "FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION"
subchapter_number: "C"
subchapter_name: "AIRCRAFT"
part_number: "29"
part_name: "AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "49 U.S.C. 106(f), 106(g), 40113, 44701-44702, 44704."
regulatory_source: "Docket No. 5084, 29 FR 16150, Dec. 3, 1964, unless otherwise noted."
cfr_part: "29"
---


# 29.175 Demonstration of static longitudinal stability.

(a) *Climb.* Static longitudinal stability must be shown in the climb condition at speeds from Vy − 10 kt to Vy + 10 kt with—

(1) Critical weight;

(2) Critical center of gravity;

(3) Maximum continuous power;

(4) The landing gear retracted; and

(5) The rotorcraft trimmed at Vy.

(b) *Cruise.* Static longitudinal stability must be shown in the cruise condition at speeds from 0.8 V<sub>NE</sub>−10 kt to 0.8 V<sub>NE</sub> + 10 kt or, if V<sub>H</sub> is less than 0.8 V<sub>NE</sub>, from VH − 10 kt to V<sub>H</sub> + 10 kt, with—

(1) Critical weight;

(2) Critical center of gravity;

(3) Power for level flight at 0.8 V<sub>NE</sub> or V<sub>H</sub>, whichever is less;

(4) The landing gear retracted; and

(5) The rotorcraft trimmed at 0.8 V<sub>NE</sub> or V<sub>H</sub>, whichever is less.

(c) *V*<sub>NE</sub>. Static longitudinal stability must be shown at speeds from V<sub>NE</sub> − 20 kt to V<sub>NE</sub> with—

(1) Critical weight;

(2) Critical center of gravity;

(3) Power required for level flight at V<sub>NE</sub> − 10 kt or maximum continuous power, whichever is less;

(4) The landing gear retracted; and

(5) The rotorcraft trimmed at V<sub>NE</sub> − 10 kt.

(d) *Autorotation.* Static longitudinal stability must be shown in autorotation at—

(1) Airspeeds from the minimum rate of descent airspeed − 10 kt to the minimum rate of descent airspeed + 10 kt, with—

(i) Critical weight;

(ii) Critical center of gravity;

(iii) The landing gear extended; and

(iv) The rotorcraft trimmed at the minimum rate of descent airspeed.

(2) Airspeeds from the best angle-of-glide airspeed − 10kt to the best angle-of-glide airspeed + 10kt, with—

(i) Critical weight;

(ii) Critical center of gravity;

(iii) The landing gear retracted; and

(iv) The rotorcraft trimmed at the best angle-of-glide airspeed.

[Amdt. 29-51, 73 FR 11001, Feb. 29, 2008]