Warbird Information Exchange

Spitfires and Hurricanes used in the desert are usually pictured with good sized filters to help keep the crud out of the engines. What kind of filters were used on P-40's operating in the same environment?

The Merlin has an updraft carburetor. That means of course that the air comes into the induction system from below the engine -- down where the sand and dirt are. Hence the volkes filter.

An Allison has a downdraft carburetor. And a very tall tall stance. So it's induction is from on top of th engine, about 9 ft up as it taxies.

The early models had no filter. The later ones used a large filter alongside the nose. In this photo the filter is behind the perforations aft of the spinner.



In this photo you can see the side cowl removed, and the paper filter in place.



In the P-40s that used the Merlin, I don't know if they used a filter at all. The engine did not have a long service life on the P-40 -- maybe that's why. Some were re-engined later with the Allison again.

Dave