Zeppelins

The Hindenburg’s destruction has been seen as one of the greatest, unforeseen tragedies in aeronautical history. Because of this one incident, the Zeppelin name would be deeply questioned for the next half century. Yet despite the number of lives lost, zeppelins were bounds ahead in engineering for their time.

Unlike modern blimps, the first lighter-than-air fliers did not hold their shape from the pressure of the gas inside, but instead made use of a lightweight, rigid airframe. Known as ‘dirigibles’, these would become the standard zeppelin design allowing ships to lift heavier loads and be fitted with stronger engines.

Zeppelin frame

Covering the frame was a cotton fabric coated with specialized metallic paints created to reflect the sun’s rays, preventing internal temperature change of the ship’s gas. Inside the elaborate framework of aluminum struts were several balloons containing either helium or hydrogen. For most dirigibles, these gasbags were made of countless sheets of a material known at the time as ‘goldbeater’s skin’, taken from the intestines of cows. About 200,000 cow’s intestines were needed for the average zeppelin!

While earlier models were shaped like hot dogs, later designs had an elongated football shape that reduced drag as well as increased stability in the air. At the end of the ship were four directional fins (two set vertically and horizontally) that steered the blimp. Since zeppelins were so large, one pilot was sanctioned in the rear solely to man the fins while another pilot at the front of the ship controlled thrust and heading.

Did you know?- The later built Graf Zeppelin used engines fuelled with a gas named blaugas. Similar to propane, it weighed roughly the same as the surrounding air and was contained uncompressed. This meant that as fuel was burnt, the airship did not have to shift ballast to retain balance during flight.

If it weren’t for the dirigible’s inventor, Led Zeppelin may still be known as the New Yardbirds. Count Ferdinand von Zeppelin was a wealthy inventor who became interested in developing a lighter-than-air balloon after witnessing events of the Franco-Prussian War of 1870-1871 where he saw the French using balloons to transport mail.

When Zeppelin completed his designs he went looking for sponsors to help get his idea off the ground, but when he presented his plans to a committee in 1984 no one showed interest. Forced to fund the project himself, the Count founded the Gesellschaft zur Förderung der Luftschiffahrt (Society for the Promotion of Airship Flight) and began construction of his prototype.

LZ 1

The first Zeppelin, dubbed LZ 1, took its maiden flight on July 2, 1900 over Lake Constance in the Bay of Manzell, Germany. True to what would be the Wright brothers’ style, the craft didn’t stay airborne for long. Airborne for only 18 minutes, LZ 1 was forced to land on the lake after its winding mechanism for keeping ballast failed. Unfortunately, when it was placed back in its hangar, the harness mechanism broke and the blimp crashed suffering damage.

Even with an essentially successful flight, many of the project’s investors decided to back out. This prompted Zeppelin to take another leap of faith and buy the company and airship for himself in 1901. With the help of donations, public funding, a mortgage on his wife’s estate, and some lottery winnings, the Count was ready to build the LZ 2. Although sadly, during its first flight in 1906, the ship’s engines failed and it was forced to make an emergency landing in the Allgau Mountains where it was destroyed beyond repair by a vicious storm.

After two failed attempts in creating his dream balloon, Count von Zeppelin finally realized success. Incorporating all usable parts of LZ 2, the LZ 3 became the first successful airship. By 1908 it had travelled a total of 4,398 kilometers (2,733 mi) in the course of 45 flights.

Did you know?- In 1930, when the Art Deco spire of the Empire State Building was built there were designs for it to serve as a terminal for passing airships. Passengers would exit the airship on a landing platform constructed on the 102nd floor. There a separate elevator traveling between the 86th and 102nd floors would transport passengers to the building’s main elevators where they could exit the building. However, after some initial testing the idea was kyboshed; powerful updrafts surrounding the skyscraper made anchoring to the spire too dangerous to be practical.

This zeppelin hangar opened by retracting is rounded outer doors.

Though many design changes would happen throughout the years of their operation, commercial zeppelins shared a majority of features during their prime. 150-160 meters (490-520 feet) in length, they could hold 22,000–25,000 cubic meters of helium or hydrogen able to carry a payload of nine tons. Powered by three 475 horsepower diesel engines, the airships could reach speeds of up to 80 Km/h (50 mph).

Did you know?- During the first World War, Zeppelins were used by the German military for scouting and precision bombing in assisting infantry forces. Yet Zeppelin was quick to realize that his airship had a fatal battle flaw, its gas chambers were easily susceptible to enemy fire. Knowing this, he developed the observational car, essentially a metal basket holding a passenger. Equipped with chart table, electric lamp, compass, telephone, and lightning conductor, the car would be lowered 750 meters below the main airframe where the occupant would give orders on navigation and what bombs to deploy. Information was transmitted through a tether cable made of high grade steel with a brass core insulated with rubber to act as a telephone cable. This allowed the ships to hide in cloud cover where they’d be out of range of artillery fire.

observation car

With the ending of the war and Germany’s defeat, came the passing of the notorious Treaty of Versailles. In the document, Allied forces demanded the deconstruction of the German air force stating no further zeppelins would be built and that all remaining models were to be given to the United States as reparations. Luckily, Zeppelin did not get to see the destruction of his great company having suffered a timely death before the war’s end. The company’s new leader, Dr. Hugo Eckener, now planned to take the zeppelin in a whole new direction; making it a messenger of peace.

On March 4, 1936, LZ 129 Hindenburg made her first flight. It was the largest airship ever constructed at 245 meters (804 feet) long and 41 m (135 feet) in diameter. In comparison, the Hindenburg was longer than three Boeing 747s placed end-to-end! Unlike today’s famous Goodyear blimp with its two pilots, the airship could accommodate 50 passengers and a crew of 40.

LZ 129 Hindenburg

What many believe to have been making a date with death, the Hindenburg’s creators did not fill their ship with hydrogen by choice. At the time, the majority of helium was being imported from the U.S., yet due to escalating tensions in Europe there was a trade embargo on the gas leaving no other viable option.

With the skepticism surrounding dirigible airships almost gone, a new generation of zeppelins is taking to the skies. A company based in California called Airship Ventures recently revealed their new line of Zeppelin ‘New Technology’ (NT) airships. A combination of new and old, the models are semi-rigid and come in at 246 feet (75 meters) long, the longest ship of its kind today.

 

Also, if you’ve read my earlier post on autogyros, you’d know that there are companies out there making remote control autogyros for hobbyists. Now the same is being done with scale blimps primarily for advertising purposes. Two great sites where you can learn more about these new technologies are advertisingballoons.com and minizepp.com.