Jacob Ellehammer
Encyclopedia
Jacob Christian Hansen Ellehammer (June 14, 1871 – May 20, 1946) was a Danish
watchmaker
and inventor born in Bakkebølle
, Denmark
. He is remembered chiefly for his contributions to powered flight.
Following the end of his apprenticeship
as a watchmaker he moved to Copenhagen
where he worked as an electronics mechanic before establishing his own company in 1898. In the beginning he produced cigarette machines, beverage machines and other electronic machinery. In 1904 he produced his first motorcycle, the Elleham motorcycle.
In 1905, he constructed a monoplane, and in the following year a "semi-biplane
". In this latter machine, he made a tethered flight on 12 September 1906.
Ellehammer's later inventions included a successful triplane and helicopter. His helicopter was a coaxial machine. A famous photo shows it hovering in 1914, though there is no evidence that it was successful in achieving translational flight. Ellehammer later studied a disc-rotor configuration - a compound helicopter with coaxial blades that extended from the hub for hover, and retracted for high speed vertical flight. Although a wind tunnel model was constructed, there's no evidence that anything more was studied.
Denmark
Denmark is a Scandinavian country in Northern Europe. The countries of Denmark and Greenland, as well as the Faroe Islands, constitute the Kingdom of Denmark . It is the southernmost of the Nordic countries, southwest of Sweden and south of Norway, and bordered to the south by Germany. Denmark...
watchmaker
Watchmaker
A watchmaker is an artisan who makes and repairs watches. Since virtually all watches are now factory made, most modern watchmakers solely repair watches. However, originally they were master craftsmen who built watches, including all their parts, by hand...
and inventor born in Bakkebølle
Vordingborg
Vordingborg is a municipality in Region Sjælland on the southeast coast of the island of Zealand in south Denmark. The municipality includes the island of Masnedø, and covers an area of 621 km². It has a total population of 46,600...
, Denmark
Denmark
Denmark is a Scandinavian country in Northern Europe. The countries of Denmark and Greenland, as well as the Faroe Islands, constitute the Kingdom of Denmark . It is the southernmost of the Nordic countries, southwest of Sweden and south of Norway, and bordered to the south by Germany. Denmark...
. He is remembered chiefly for his contributions to powered flight.
Apprenticeship
Apprenticeship is a system of training a new generation of practitioners of a skill. Apprentices or protégés build their careers from apprenticeships...
as a watchmaker he moved to Copenhagen
Copenhagen
Copenhagen is the capital and largest city of Denmark, with an urban population of 1,199,224 and a metropolitan population of 1,930,260 . With the completion of the transnational Øresund Bridge in 2000, Copenhagen has become the centre of the increasingly integrating Øresund Region...
where he worked as an electronics mechanic before establishing his own company in 1898. In the beginning he produced cigarette machines, beverage machines and other electronic machinery. In 1904 he produced his first motorcycle, the Elleham motorcycle.
In 1905, he constructed a monoplane, and in the following year a "semi-biplane
Ellehammer semi-biplane
-References:* ...
". In this latter machine, he made a tethered flight on 12 September 1906.