Demonstration of static longitudinal stability.

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