FAR 23.2165 — Flight in Icing Conditions
FAR 23.2165 sets performance and flight characteristics requirements for Part 23 airplanes certified to fly in icing conditions. Key rules explained.
In Plain English
FAR 23.2165 lays out what an airplane manufacturer (the applicant) must demonstrate when seeking certification to fly a Part 23 airplane into icing conditions as defined in Appendix C, Part 1 of Part 25.
Key requirements:
- The airplane must meet all Subpart B performance and flight characteristics requirements while operating in icing with the ice protection system working normally. The only exceptions are spin requirements and any tests required above:
- 250 KCAS,
- V/Mo or Vmo, or
- a speed at which the airframe is shown to be free of ice accretion.
- Stall warning must be provided to the pilot the same way in icing conditions as in non-icing conditions — no different cue or system.
- The applicant must provide a means to detect icing conditions for which the airplane is not certified, and show the airplane can avoid or exit those conditions.
- The applicant must publish an operating limitation that prohibits intentional flight, including takeoff and landing, into icing conditions for which the airplane isn't certified.
Operationally, this is why your AFM contains specific icing limitations and why ice detection equipment matters — the airplane is only proven safe in the icing envelope it was tested for.
Regulation Text
14 CFR § 23.2165§ 23.2165 Performance and flight characteristics requirements for flight in icing conditions.
(a) An applicant who requests certification for flight in icing conditions defined in part 1 of appendix C to part 25 of this chapter, or an applicant who requests certification for flight in these icing conditions and any additional atmospheric 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) Compliance with each requirement of this subpart, except those applicable to spins and any that must be demonstrated at speeds in excess of—
(i) 250 KCAS;
(ii) V/Mor V; 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 show the airplane's ability to avoid or exit those conditions.
(c) The applicant must develop an operating limitation to prohibit intentional flight, including takeoff and landing, into icing conditions for which the airplane is not certified to operate.
[Doc. No. FAA-2015-1621, Amdt. 23-64, 81 FR 96689, Dec. 30, 2016, as amended by Doc. No. FAA-2022-1355, Amdt. 23-65, 87 FR 75710, Dec. 9, 2022]
Oral Exam Questions a DPE Might Ask
Q1If an airplane is certified for flight in icing conditions under Part 23, what must the manufacturer have demonstrated about its performance?
Per FAR 23.2165(a), the applicant must show compliance with each Subpart B performance and flight characteristics requirement in the certified icing conditions with the ice protection system in normal operation, except for spin requirements and tests above 250 KCAS, V/Mo or Vmo, or a speed where the airframe is shown to be ice-free.
Q2How must stall warning behave in icing conditions on an airplane certified under FAR 23.2165?
Under FAR 23.2165(a)(2), the means by which stall warning is provided to the pilot must be the same in icing conditions as in non-icing conditions, so the pilot gets a consistent cue regardless of the environment.
Q3What must an applicant do about icing conditions the airplane is NOT certified for?
FAR 23.2165(b) and (c) require the applicant to provide a means to detect any non-certified icing conditions, demonstrate the airplane can avoid or exit them, and establish an operating limitation prohibiting intentional flight, takeoff, and landing into those conditions.
Studying for a checkride?
Related Sections in Part 23