ASME: Pratt & Whitney R-1340 Wasp Radial Engine

ASME Landmark # 260 (1925)
Pratt & Whitney, East Hartford
May 2019

Everything I read online tells me that there’s an original 1925 Wasp engine up at the New England Air Museum in Windsor Locks. And I’m 100% sure there is. The American Society of Mechanical Engineers National Landmark plaque is probably up there too.

But you know what? The engine hadn’t been designated landmark status when I visited NEAM, and I’m not going back up there just for that. Especially since the same engine is also on display at the Pratt & Whitney Hangar Museum in East Hartford.

And since East Hartford is the home of P&W, I’m sticking to East Hartford. It certainly doesn’t matter, as this engine should be displayed in every aviation history museum – as the dang thing revolutionized the industry.

Aircraft engines, considered unreliable during the first 20 years of aviation due to their need for liquid-cooling, heavy weight and other inconsistencies, were given a revolutionary boost with the development of Pratt & Whitney’s R-1340 Wasp Radial Engine in 1925.

Engineers led by Chief Executive Officer Fredrick Rentschler, Vice President of Engineering George Mead, and Chief Engineer Andy Willgoos implemented a number of improvements: a single piece master rod allowed the engine to operate at a higher number of revolutions per minute, producing more horsepower; a two-piece crankshaft able to maintain required tolerances – making the single piece master rod possible; and a split crankcase with two identical halves. This improve the engine’s manufacturability, reducing assembly time and complexity.

These innovations set a new standard for aircraft engine reliability, impacting commercial aviation and transcontinental mail service, and leading to more advanced aircraft in the late 1920s and early 1930s – such as the Boeing 247. Over 90 versions of the R-1340 engine are in operation today.

It’s been almost a century since the air cooled engine was pioneered at P&W and its still going strong. That’s amazing.