CS 22.173 Static longitudinal stability

• ED Decision 2003/13/RM found in: Sailplane Rule Book - Part-SAO Part-SFCL CS-22 (Nov 2022)

CS 22.173 Static longitudinal stability ED Decision 2003/13/RM (a) Under the conditions and throughout the speed range specified in [CS 22.175](#_DxCrossRefBm2056272072): (1) The slope of the curve, stick force versus speed, must be positive and have a value such that any significant speed change will cause a variation in stick force plainly perceptible to the pilot. (2) The slope of the curve, stick displacement versus speed, must not be negative, except that a negative slope may be acceptable provided that it can be demonstrated that there is no difficulty in control. (See [AMC 22.173(a)](#_DxCrossRefBm2056272071)) (b) The air speed must return to within ±15% or ±15 km/h of the original trimmed speed, whichever is the greater when the control force is slowly released at any trimmable speed up to VNE and where applicable VNE and down to the appropriate minimum speed for steady unstalled flight. In addition, for a powered sailplane with the engine running, this requirement must be met at all allowable power settings. (See [AMC 22.173(b)](#_DxCrossRefBm2056272070))