CS 22.335  Design air speeds

CAA ORS9 Decision No. 1

The selected design air speeds are equivalent air speeds (EAS): 

(a) Design manoeuvring speed V_A

where: 

V_S1 = estimated stalling speed at design maximum weight with wing flaps neutral and air brakes retracted

(b) Design flap speed, V_F 

(1) For each landing setting, V_F must not be less than the greater of: 

(i) V_S1, where V_S1 is the computed stalling speed with wing-flaps neutral at the maximum weight. 

(ii) 2.0 V_SF, where V_SF is the computed stalling speed with wing-flaps fully extended at the maximum weight. 

(2) For each positive en-route setting, V_F must not be less than the greater of: 

(i) 2.7 V_S1, where V_S1 is the computed stalling speed at design maximum weight with wing flaps in the particular positive en-route setting. 

(ii) 1.05 V_A, where V_A is determined in accordance with sub-paragraph (a) of this paragraph, i.e. for wing-flaps neutral. 

(3) For all other settings, V_F must equal V_D. 

(c) Design Gust Speed V_B. V_B must not be less than V_A. 

(d) Design Aerotow Speed V_T. V_T must not be less than 125 km/h. 

(e) Design Winch-launching Speed V_W. V_W must not be less than 110 km/h. 

(f) Design Maximum Speed V_D. The design maximum speed may be chosen by the applicant but must not be lower than: 

(km/h) for sailplanes of Category U

(km/h) for sailplanes of Category A

where: 

         Wing loading (daN/m) at design

    CD_min=      The lowest possible drag coefficient of the sailplane 

For a powered sailplane, V_D must also not be lower than 1.35 V_H.