CS 22.201  Wings level stall

CAA ORS9 Decision No. 1

    (a) Stall demonstrations must be conducted by reducing the speed by approximately 2 km/h per second until either a stall results as evidenced by a downward pitching motion or rolling motion not immediately controllable or until the longitudinal control reaches the stop. It must be possible to produce and correct roll and yaw by unreversed use of the controls until the stall occurs. 

    (b) It must be possible to prevent more than 30° of roll by normal use of the controls during recovery. There must be no uncontrollable tendency of the sailplane to spin. 

    (c) Stalling behaviour must not be unduly sensitive to sideslip. (See AMC 22.201(c)) 

    (d) The loss of altitude from the beginning of the stall until regaining level flight by applying normal procedures and the maximum pitch attitude below the horizon must be determined. (See AMC 22.201(d)) 

    (e) With the sailplane in straight flight at 1.2 VS1 in the configuration appropriate to winch-launching by pulling rapidly on the control stick, a pitch attitude approximately 30° above the horizon must be achieved and the resulting stall must not be severe and such as to make prompt recovery difficult. 

    (f) Compliance with the requirements of sub-paragraphs (a) through (d) and (g) of this paragraph must be shown under the following conditions: 

      (1) wing-flaps in any position; 

      (2) air brakes retracted and extended; 

      (3) landing gear retracted and extended; 

      (4) sailplane trimmed to 1.5 VS1 (if fitted with a trimmer); 

      (5) additionally, for powered sailplanes:–  (i) cowl flaps in appropriate configuration;  (ii) power: 

      i. engine idling, and 

      ii. 90% of maximum continuous power; 

      iii. propeller in take-off position 

    (g) For sailplanes equipped to carry water ballast, it must be shown that it is possible to regain level flight without encountering uncontrollable rolling or spinning tendencies in the stall demonstration of sub-paragraph (a) of this paragraph with the asymmetry that may result from any single malfunction of the system.