Zeppelin Museum Friedrichshafen, Germany
The Zeppelin Museum Friedrichshafen is a museum in Friedrichshafen, Germany, the birthplace of the Zeppelin airship. The museum houses the largest collection of airship travel in the world and chronicles the history of Zeppelin airships. The museum has been at its current location at Hafenbahnhof since reopening in 1996.
Address: Seestrase 22, 88045 Friedrichshafen, Germany
Contact: https://www.zeppelin-museum.de/en
86/A - Zeppelin Museum Friedrichshafen
Paul Jaray
Paul Jaray (1889–1974), a Zeppelin aerodynamicist, invented the "J-Rad" in 1919 - 1921, pioneering a series-produced, level-driven recumbent bicycle designed to reduce air resistance. Built by Hesperus-Werke in Stuttgart (1922–1923), about 2,000 units were sold before production ceased due to fatal accidents from faulty materials.
Key History and Features of the J-Rad
Design & Engineering: Unlike conventional bicycles, the Jaray bike was a recumbent design, allowing the rider to sit upright with legs extended forward to reduce aerodynamic drag. It featured a unique lever-driven (treadle) system rather than a chain-driven mechanism.
Production: Approximately 2,000 of these "J-Rad" machines were produced between 1922 and 1923, primarily finding success in the Netherlands.
Performance: Prototypes included variations with 26-inch wheels and later models with smaller front wheels for improved handling. It featured 3-speed gearing via adjustable leverage points.
Safety & Discontinuation: The bike was considered fast and efficient, but production stopped in 1923 following fatal accidents attributed to poor-quality, economical raw materials rather than a flawed fundamental design.
Significance: Jaray, also known for his work in automotive streamlining, applied his wind-tunnel expertise to make the bicycle more efficient, with some models designed to include optional, removable, or clip-on, streamlined "skirts" or canopies.
