Mannerstedt made an almost unknown 42-cylinder engine with six rows of seven-cylinders, separated in two groups of three rows.

-Between both rows, a superimposed gearbox makes the propeller shaft higher than the two crankshafts, which although joined together are individual, avoiding unwanted torques in long lengths.

“Mannerstedt, 42-cylinder” (PiP)

-The cylinders of the rows are aligned so that the shaft passes between the three rows of the first group, and a weapon can be placed between those of the second group, firing through the hollow propeller shaft.