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Does anyone know if any regulations exist making it a requirement for general aviation aircraft to have ice protection systems?

And any insights on why general aviation aircraft tend to use rubber boots and fluid based systems as opposed to electrothermal solutions?

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    $\begingroup$ welcome to aviation.SE. you ask about regulations. could you please specify the jurisdiction? $\endgroup$
    – Federico
    Oct 30, 2018 at 10:29
  • $\begingroup$ The UK or US, thank you $\endgroup$
    – Gen
    Sep 6, 2020 at 15:32

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Does anyone know if regulation exists making it a requirement for general aviation aircraft to have ice protection systems?

In specific answer to your question: Yes, there are regulations for general aviation aircraft to have ice protection systems if the aircraft is to be flown into known icing conditions.

  1. FAR Part 23.2540 (applies to general aviation type aircraft) does specify certification criteria if the manufacturer is requesting approval for flight into known icing conditions.

  2. FAR Part 91, Subpart F- applying to Large and Turbine-powered mulitiengine airplanes and Fractional Ownership Program aircraft, does specifiy the conditions, equipment, etc. required to fly into known icing conditions. (business jets/turbo props, etc)

  3. General Aviation aircraft operating under certain regulations, FAR 135.227 for example, are subject to specific regulations pertaining to operations into known icing conditions .

  4. FAR Part 91.9, applying to all Part 91 operations, while not uniquely applicable to operations in icing conditions, does require compliance with all operating limitations published in a flight manual, placard, POH, etc. So, if the POH for the aircraft in question prohibits flight into known icing conditions (as many general aviation aircraft manuals/POHs do) then it cannot be done. However, there are also many general aviation aircraft that are permitted to fly into known icing conditions in accordance with stipulations published in the POH (or similar).


And any insights on why general aviation aircraft tend to use rubber boots and fluid based systems as opposed to electrothermal solutions?

The only insight I can offer regarding boots/fluid systems versus heated solutions is the manufacturer's choice based on performance considerations, functional utility, and interoperablity with associated systems. For example, an engine driven air pump for deice boots creates a performance overhead that may not be worth the expense, assuming it's an option, based on how the airplane will be used. Electrically heated props (heated near the hub) are another option for many general aviation airplanes that can be added assuming certification for flight into icing exists. Bottom line is, I don't think there is a "preference" for general aviation airplanes, I believe design considerations and after-market options are the predominate factors underlying the type of deicing/anti-ice equipment available in most general aviation airplanes.


Here is an excellent FAA Advisory Circular that pertains to your question:

AC 91-74B - Flight in Icing Conditions

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  • $\begingroup$ Thank you, very helpful $\endgroup$
    – Gen
    Sep 6, 2020 at 15:33
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An airplane has to have a deicing or anti-icing system that is certified to a certain performance standard or it can't fly in icing conditions. Icing conditions are defined nowadays as any visible moisture with temperature below a few degrees above freezing, so without a certificated anti-icing/deicing system the airplane is for practical purposes confined to below the freezing level if it has to fly through any cloud.

Boots/fluids are used because they only need compressed air or a reservoir/pump to work and take way less power to function vs leading edge heating systems that traditionally have depended on large amounts of bleed air (or electricity in the case of the 787) from a jet engine. Even smaller jets like the early Cessna Citations could not produce enough bleed to anti-ice the wings and depend on boots.

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  • $\begingroup$ Thank you very much $\endgroup$
    – Gen
    Sep 6, 2020 at 15:33

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