IRImplementing rule
CS 23.2165Performance and flight characteristics requirements for flight in icing conditions
(a)An applicant who requests certification for flight in icing conditions must show the following in the icing conditions for which certification is requested under normal operation of the ice protection system(s):
(1)comply with each requirement of this Subpart, except those applicable to spins and any that must be demonstrated at speeds in excess of:
(i)250 knots calibrated airspeed (KCAS);
(ii)VMO or MMO or VNE; or
(iii)a speed at which the applicant demonstrates the airframe will be free of ice accretion;
(2)the means by which stall warning is provided to the pilot for flight in icing conditions and non-icing conditions is the same.
(b)If an applicant requests certification for flight in icing conditions, the applicant must provide a means to detect any icing conditions for which certification is not requested and demonstrate the aeroplane’s ability to avoid or exit those conditions.
(c)The applicant must develop an operating limitation to prohibit intentional flight, including take-off and landing, into icing conditions for which the aeroplane is not certified to operate.
IR · CS 23.2165 — CS-23 · ED Decision 2017/013/R · CS-23 Easy Access Rules · EAR revision 13 May 2026