Carb ice chart.

[Guest]

[ptwizz]

As a point of interest, are there any icing issues with fuel injection engines, such as perhaps icing of the throttle valve?

[Steve]

I use this one because I prefer celcius:

http://ibis.experimentals.de/images/carbicingfromcaassl14.gif

[kentmartin]

As a point of interest, are there any icing issues with fuel injection engines, such as perhaps icing of the throttle valve?

In PPL school I was taught that icing impacting engine performance is not an issue with fuel injection... of course icing of wings, control surfaces etc still pose, ahem, challenges

[ScoobySnacks]

Icing is mainly caused by the pressure (and hence temperature) drop across the venturi, coupled with evaporative effects from the fuel. An injected engine doesn't require the venturi to ensure mixing and atomization, so in effect doesn't have on, significantly reducing the likelihood of intake icing.

[ptwizz]

It is true that injected engines don't have a venturi as such, but they (i.e. our petrol engines) still have a throttle which causes a significant pressure change, more than the venturi of a conventional carburettor.

The difference would be that the carburettor has a fuel jet at the location of the pressure change. Evaporation of the fuel has a cooling effect which may contribute to icing. The icing then affects the flow around the jet and prevents the carburettor from operating properly, resulting in poor engine performance.

I am interested to know whether injected engines avoid icing altogether (by removing the jet from the area of pressure drop) or are simply more tolerant of icing?

[AdEves]

Certainly in the many injected aircraft I have flown carb ice just wasn't considered an issue.

[OldFart]

I have also never heard of a case of engine icing with fuel injected engines.  They are not fitted with any sort of intake heater, so it's difficult to see how you could control it if there were.