The first Zeppelin airship in 1900 — with Bosch magneto ignition
In the air thanks to Bosch
It was a sensational experiment. Count Ferdinand von Zeppelin’s first airship was ready for an initial flight attempt in 1900. Among those Zeppelin had to thank for making this project possible were Robert Bosch and his ignition system. In this way, Bosch helped pave the way for a spectacular chapter in aviation.
An unusual spectacle
It was the evening of July 2, 1900. A gigantic cigar-shaped object on a wooden pontoon in Lake Constance in southern Germany was soon to rise into the air. Thousands of onlookers made their way to the lakeshore near Friedrichshafen for the spectacle. The first Zeppelin-type airship, designated LZ 1, was ready for its first attempt at flight.
Its builder Count Ferdinand von Zeppelin was probably very tense as he climbed into the forward gondola at 6:50 p.m. After all, it was the premiere of his new design, and he couldn’t afford to have anything go wrong. Another airship pioneer’s project had failed shortly before.
Due to delays in the final checks and unfavorable wind conditions, the launch was repeatedly postponed for safety reasons. Construction had been completed in mid-June 1900, and the shareholders of the Gesellschaft zur Förderung der Luftschifffahrt (Society for the Promotion of Airship Flight), the press, and selected guests began receiving their invitations on June 16. The test flight had been announced for June 29, so the guests were forced to wait for three days.
Finally, at 8:03 p.m., the 56 gymnasts and firefighters holding the 28 mooring lines were given the brief command “Go!” They released the lines and the LZ 1 began ascending to a height of around 300 meters. At 8:15 p.m., Graf Zeppelin gave the signal to land, and five minutes later, the LZ 1 touched down near Immenstaad. All in all, the attempt lasted just about 17 minutes. However, it demonstrated that the technical concept was fundamentally sound. Also on board: a Bosch magneto ignition device. It was the only option that guaranteed reliable ignition for the LZ 1 and thus ensured dependable operation of the two gasoline engines on board.
A new airship concept
The prelude to this memorable event began in 1887. Count Zeppelin, then a 49-year-old highly decorated military officer from a noble Mecklenburg family, wrote an official letter to the King of Württemberg in which he set out his thoughts on steerable airships. The first patent application followed in 1891, but Zeppelin withdrew it due to the need for improvements. After numerous revisions and a renewed application, in 1895 he was granted a patent in the Sport class for a steerable “airship train.”
Zeppelin championed the concept of a rigid airship. It was the counterpart to the non-rigid airships, or blimps, which had been around since the middle of the 19th century. These were given their shape solely by filling them with hydrogen or helium gas. To ensure that the blimps maintained their shape, a slight overpressure was created inside the gas-filled envelope by means of ballonets (air bags) that could be inflated and deflated.
Zeppelin’s rigid airship, on the other hand, had a metal skeleton. This was covered with a fabric shell and carried a number of gas cells inside, which were filled with hydrogen gas to make the airship lighter than air and thus allow it to fly. Zeppelin’s design presented two decisive advantages over that of the non-rigid airship: first, greater stability, which made the ship suitable for powerful engines and high speeds; and second, the ship’s ability to maintain its shape in the face of fluctuating air pressure, plus the option of releasing lifting gas so as to descend without deforming the envelope.
Fundraising and crafting a vision
Zeppelin tried to get the military interested in his project, as he believed that this would secure funding for construction. However, when the commission appointed by Kaiser Wilhelm II declined, Zeppelin decided to try a different tack. With the support of the Verein Deutscher Ingenieure (Association of German Engineers), he founded the Society for the Promotion of Airship Flight in 1898 with capital stock of 800,000 reichsmarks, a good half of which he contributed himself. The LZ 1 had already been planned and designed between 1892 and 1894. At 128 meters long and 11.7 meters in diameter, it was to be the biggest airship to date.
Construction began in 1898 in a factory owned by the entrepreneur Carl Berg in the city of Lüdenscheid. Berg was deeply interested in the development of airship travel. He had already supported the airship project of Zeppelin’s rival David Schwarz and, after that project failed, turned to Count von Zeppelin, supporting his Society for the Promotion of Airship Flight with a substantial investment. The airship was assembled in a floating shed built especially for this purpose and was moored in Lake Constance, off the town of Manzell near Friedrichshafen.
An impressive appearance
Inside the 128-meter-long fabric-covered aluminum frame were 17 cells filled with a total of 11,300 cubic meters of gas. In total, the LZ 1 weighed around 10,000 kilograms.
Two gondolas, each 7 meters long, were installed on the underside of the cigar-shaped ship, each fitted with a 16-horsepower Daimler gasoline engine. The ship could store a total of 100 liters of fuel, and so the engines could provide a ten-hour journey at a calculated cruising speed of 28.8 kilometers per hour.
The Bosch ignition system was a stroke of luck for Zeppelin. The established (albeit problematic) hot-tube and battery-powered ignition systems were common in vehicles up to around 1900, but both were out of the question for the LZ 1. Battery-powered ignition systems required external power from a battery that had to be recharged after a short time and while stationary. Hot-tube ignition wasn’t suitable for airship use because it required a burner with an open flame — a considerable fire risk, given that the lifting gas hydrogen was highly flammable.
There was therefore only one suitable ignition system: the low-voltage magneto, which Robert Bosch had made suitable for use in vehicle engines in 1897. Type C magneto ignition devices were used, which Bosch had presented the previous year at the first “International Motor Show” in Berlin. The use of this technology demonstrated Zeppelin’s confidence in the Stuttgart manufacturer’s products.
No fire hazard and long range, thanks to Bosch
Even if the LZ 1’s first voyage didn’t lead to the success that Count von Zeppelin had anticipated, it did prove that the design principle worked. Bosch used this as proof of the reliability of its ignition system when it counted. And for Zeppelin, it solved a problem that had stood in the way of operating its airships right up until the last minute. As a result, the Bosch ignition became a constant companion of airship technology until the end of the latter’s era.
Author: Dietrich Kuhlgatz