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§ 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 VNE−10 kt to 0.8 VNE + 10 kt or, if VH is less than 0.8 VNE, from VH − 10 kt to VH + 10 kt, with—
(1) Critical weight;
(2) Critical center of gravity;
(3) Power for level flight at 0.8 VNE or VH, whichever is less;
(4) The landing gear retracted; and
(5) The rotorcraft trimmed at 0.8 VNE or VH, whichever is less.
(c) VNE. Static longitudinal stability must be shown at speeds from VNE − 20 kt to VNE with—
(1) Critical weight;
(2) Critical center of gravity;
(3) Power required for level flight at VNE − 10 kt or maximum continuous power, whichever is less;
(4) The landing gear retracted; and
(5) The rotorcraft trimmed at VNE − 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]