There are on actual cross channel operations two squadrons of P-47’s and one P-38 using 150 Grade fuel.

        The results to date are of such a nature as to presume the gasoline marks a definite trend in the increase of speed and climb characteristics. The tests also reveal the engines will take the fuel; a few minor modifications must be made. These modifications can be done by first echelon maintenance. The main difficulty is in the spark plugs. These must be changed for each raise of 2 inches of manifold pressure.

MANIFOLD PRESSURE INCREASES

P-47    Water injection and paddle blade propeller now held to 66 inches but can be raised to 70 inches.

P-38     The range is 60-66 however by the change of plugs the range can be 70-75 inches. At present they are set at 65 but will probably soon be changed to 70 inches.

P-51     Work on this aircraft is being done mainly in the States, however there are tests being run at Bovindon. Tests to date show an increase of manifold pressure to 65 inches.

        Modification kits are made up and are at present in the States. The changes to be made for the use of this fuel are as follows.

        P-47:
                A23 supercharge regulator.
                Water pressure gauge.
                Exhaust packing.
                Water plug spring strengthened.
                Fuel pump.
                Exhaust system (Stainless Steel).
                Reinforce ducts.
                Spark plugs.

        P-51:
                Manifold pressure regulator
                Supercharger drain restrictor.
                Intake manifold seal.
                Spark plugs.
                Exhaust stacks strengthened.
                Boost setting
                Supercharger aneroid control.