This Pratt & Whitney 28-cylinder 4-row radial engine was designed and built by Dennis Fadden, of Canada, in the 1980s. The engine is 17”-long, 17”-wide, and 17”-high. The model was designed to operate on gasoline and spark ignition and sports a 12-inch, 3-blade adjustable pitch propeller. Dennis began the project in the mid-1980’s but moved on to other projects and never got back to this one.
The engine (without cylinder heads) measure 6 inches in diameter and is 21 inches long including the propeller hub. The crankshaft is assembled inside and includes gears for distributors and a 3-to-1 planetary gear set driving the propeller. The rear case houses two oil pumps for dry sump lubrication and a centrifugal supercharger to increase pressure to the cylinders.
The full-size engine designated R-4360 (4360 cubic inches) Wasp Major is compose of four rows of seven-cylinder radial engines. Each row is staggered to assist the distribution of cool air to the rear rows of cylinders during operation. Sheet metal shrouds encased the heads and cylinders to direct the flow of air around and through the rows of cylinders. The engine was dubbed the “Corn Cob” due to its appearance. It was used in such aircraft as the Consolidated B-37, Boeing Stratocruiser, B-50, 377, Spruce Goose and the Super Corsair. Courtesy of Dennis Fadden.
![A rear view of the Pratt & Whitney 28-cylinder engine.](https://craftsmanshipmuseum.com/wp-content/uploads/2023/01/Knapp344b-125x125.jpg)