Duesenberg Model H (also referred to as the Duesenberg H or Duesenberg H Direct V-16 ) was a large water-cooled V-16 aircraft engine developed by the Duesenberg Motors Corporation during World War I. It was one of the most powerful and largest-displacement aero engines designed in the United States at the time, with a displacement of 3,393 cubic inches (55.6 L). Intended for military use, the engine was projected to deliver 700 hp (522 kW) in direct-drive configuration and up to 800 hp (597 kW) with gear reduction, though full-power military certification tests were never completed due to the Armistice of 1918. Only four prototype engines were ordered by the U.S. military. The Model H never entered production or saw combat service, largely because its extreme size made it unsuitable for contemporary aircraft. Two examples survive and are preserved in major museums.

Development

The Duesenberg brothers, Fred and August, were already renowned for high-performance racing and marine engines when the United States entered World War I in 1917. Their company, Duesenberg Motors Corporation (headquartered in New York with manufacturing in Elizabeth, New Jersey), initially received contracts to build Liberty V-12 and later Bugatti-King U-16 engines. Dissatisfied with the power output of existing designs, Fred Duesenberg proposed an even larger and more powerful engine capable of 800 horsepower. The U.S. military awarded a contract for four test engines in early 1918. Development occurred rapidly in a new, state-of-the-art test facility. The first runs took place in mid-1918, and testing included a 16-foot test propeller club. Early dynamometer results were promising, with indications that 900 hp might be achievable at higher rpm. However, the Armistice on 11 November 1918 ended the war before official full-power military tests (scheduled for 31 December 1918) could be completed. The program was cancelled, and no further engines were built.

Design

The Model H was a 45° V-16 with a single crankshaft. Each cylinder was fabricated individually from a machined barrel surrounded by eight 18-gauge steel stampings that were gas-welded to form an integral water jacket (similar to contemporary Mercedes practice). This construction method was chosen for cost and manufacturing efficiency. It employed Duesenberg's signature walking-beam valve gear. Three valves per cylinder were used: one large intake valve and two smaller exhaust valves, all operated by long rocker arms from a single camshaft located in the crankcase. The intake valve was positioned to direct cool incoming charge over the exhaust valves, improving cooling and mixture preparation. Ignition was provided by a dual system consisting of two Delco battery-powered distributors and a pair of Dixie magnetos. Fuel delivery came from four Miller updraft carburetors. The engine was offered in both direct-drive and geared (0.758:1 reduction) versions to allow higher crankshaft speeds while driving large propellers. Its overall length exceeded seven feet (2.13 m), making it one of the physically largest aero engines of the era.

General characteristics

Components

Performance

Testing and operational history

Ground testing was conducted extensively in Duesenberg's new engine test house. The engine demonstrated strong torque and good acceleration characteristics. However, mechanical teething problems (common in such a large, high-power design) prevented completion of the official military certification runs. The engine was publicly displayed at the New York Aero Show after the war, where its massive size dwarfed contemporary engines such as the King-Bugatti U-16. No aircraft were ever designed or modified to accept the Model H, as its dimensions exceeded the capabilities of existing airframes. The end of the war and the rapid demobilization of the U.S. military ended any further interest.

Legacy

Although it never flew, the Duesenberg Model H remains notable as the largest-displacement engine ever produced by the Duesenberg brothers and one of the most ambitious American aero-engine projects of World War I. Its advanced features—fabricated cylinders, walking-beam valve gear, and high specific output for the era—reflected the innovative engineering that later made Duesenberg famous in automobile racing and luxury cars. The engine is occasionally exhibited alongside other Duesenberg aircraft and automotive powerplants.

See also

Related lists

External links

  • Media related to Duesenberg H Direct V-16 engine at Wikimedia Commons