1946: A Transportation Trailblazer Finishes His Life’s Journey in Copenhagen

May 20, 1946

Jacob Ellehammer, a longtime watchmaker who also used his mechanical talents to make seminal contributions to transportation, died in Denmark’s capital city of Copenhagen. He was 74.

Ellehammer was born in the Danish village of Bakkebølle on June 14, 1871. After completing his apprenticeship as a watchmaker, he moved to Copenhagen and found employment there working with various types of electrical machinery. He established his own company in 1898. This company’s products included machines for making beverages and cigarettes.

Ultimately, however, Ellehammer focused his considerable skills and curiosity on transportation-oriented machinery instead. In 1904, for example, he manufactured his first motorcycle. A pioneering feature of this motorcycle was that the engine for it was beneath the seat.

Ellehammer specifically used single-cylinder Peugeot Frères engines for his motorcycles. He soon utilized parts from that type of engine to build an engine for airborne transportation. This led to Ellehammer’s creation of the world’s first air-cooled radial engine, a three-cylinder engine outfitted with Peugeor Frères cylinders and heads on an engine block. The early version of this engine turned out to be insufficient for aircraft, so Ellehammer developed cylinders with a larger volume that were fitted on an even an even bigger engine block. This new-and-improved engine was able to lift aircraft off the ground.

By 1907, Ellehammer had come up with a notably more powerful five-cylinder engine. He installed this engine in a triplane that he built and was subsequently able to make quite a few short free-flight hops while piloting this aircraft.

Another one of Ellehammer’s well-known efforts involving human flight was an experimental full-size helicopter that he constructed in 1912. Ellehammer outfitted this aircraft with two contra-rotating discs. Each of these discs had six vanes. In an early example of cyclic control, the pitch of these vanes could be modulated by the pilot operating the helicopter. While there is no evidence that this aircraft successfully achieved translational flight, it was able to make numerous free take-offs. In addition, there is a still-existing 1914 photo that shows this helicopter actually hovering above the ground.

In recognition of his role in further exploring the frontiers of aviation theory and knowledge, Ellehammer was posthumously inducted into the International Air & Space Hall of Fame at the San Diego Air & Space Museum in 1986.

Image Credit: Public Domain

For more information on Jacob Ellehammer, please check out https://www.gracesguide.co.uk/Jacob_Ellehammer

Additional information on the Ellehammer helicopter is available at https://en.wikipedia.org/wiki/Ellehammer_helicopter