Does the plane HAVE to have carb heat to pass inspection?

[JTMartin]

I'm building a small LSA and using a snowmobile engine. I know planes use carb heat for icing issues.
I have ridden both snowmobiles and dirt bike in the winter on snow and frozen lakes and never had problems.
To pass the airworthiness inspection does the LSA Have to have carb heat?
Thanks for your time.

[Dana]

I assume you mean you're building an E-AB that meets LSA specs, because if you're building an LSA kit you have to set it up exactly per the plans.

On an experimental I'm pretty sure there's no legal requirement for carb heat, but some DARs will insist on it being there anyway.

But... just because you've never seen carb ice on these engines in the winter doesn't mean anything, carb ice isn't common in winter. It's cool to warm humid days that it can get you. That said, ice is rarely a problem with 2-strokes and slide carburetors... but it can happen.

[JTMartin]

Thanks for the reply. I can add electrical carb heat very easy and will probably do that. The way airplanes do it with heated intake air can be done but is a lot more work I wish not to do.

[Mel]

Many aircraft that use snowmobile engines take the intake air from the plenum around the engine. This air is already warmed and may not need addition heat. OTOH, if you are using external "ram" air for carb intake, additional carb heat may be a good idea. Carb heat is not a "requirement" for certification, but an inspector can deny for any reason he/she feels is a safety factor. BTW, these types of carbs can ice up. It's somewhat rare but has happened.

[JTMartin]

Many aircraft that use snowmobile engines take the intake air from the plenum around the engine. This air is already warmed and may not need addition heat. OTOH, if you are using external "ram" air for carb intake, additional carb heat may be a good idea. Carb heat is not a "requirement" for certification, but an inspector can deny for any reason he/she feels is a safety factor. BTW, these types of carbs can ice up. It's somewhat rare but has happened.

This engine is a water cooled 2-stroke so to get warm air I would need to make something that goes around the exhaust. I can get electric carb heat to insert on the side of the carbs like on the Yamaha rhino. Hopefully that will be fine because I don't want to do the other way using the exhaust.

[DaleB]

Personally... if I were doing it, I'd think about an electric heater strip wrapped around the carb throat, with an automatic thermostatic control. Then you have carb heat, when it's needed, without having to do anything yourself. Let the electrons do the work, they don't charge anything. Well, they do, but... you know what i mean.