This engine is no longer on display at Wings of History.

Menasco Motors Corporation was founded by Albert Menasco in 1926.  At the request of the industry legend, John Northrop, Al Menasco developed the inverted inline 4-cylinder engine which was used in the 1929 Northrop Avion EX-1, the first of Northrop’s flying wings.  The inverted inline design offered many advantages for pilots and aircraft builders, including:

The first inline Menasco engine, the four-cylinder A4, was certified in May 1930 followed a short time later by the six-cylinder inverted A6.

Claude Ryan was one of Menasco’s best customers.  Ryan used the engine first in his Sport Trainer, the Ryan ST/STA, and then in military derivatives such as the PT-16, PT-20 and STM between 1934 and 1941.

Engine NameMenasco D4-87
ManufacturerMenasco Motors Corp.
Date of Manufacture1941
Cylinder Configurationinverted inline
Number of Cylinders4
Bore (inches)4.75
Stroke (inches)5.125
Displacement (cubic inches)363
Dry Weight (lb)320
Horsepower125-134hp @ 2260 rpm
Compression Ratio6.0:1
Rated Speed2175 rpm