Rising from the ashes

Zeppelin airships are making a comeback

On May 6, 1937, the German airship Hindenburg caught fire as it was docking at Lakehurst Field, New Jersey. Although only 35 of the 97 persons on board died, making it a small disaster by aviation standards, it did trigger a fear psychosis that effectively ended the commercial airship industry. Some 80 years later, a new high-tech generation of airships may be making a comeback. In June, a collaborative effort between Goodyear and Zeppelin will launch test flights of a new airship that could push the envelope somewhat in terms of new technology. Several other companies are also in the game of 21st century airship design and development. If all goes well, these powered balloons could end up being a serious transport alternative.

Zeppelin, the company founded by Graf Ferdinand Von Zeppelin in 1908, built the ill-fated Hindenburg. Now it runs 12 low-key commercial airship services, carrying over 21,000 passengers last year on trips across Germany and Switzerland. It is considering opening services in China. Lockheed Martin is designing a “super airship” designed to carry massive amounts of cargo and high-end passengers. The US Defense Department is funding research into heavy payload dirigibles as well. These new airships are based on the same principles Count Zeppelin followed 110 years ago. They have a large rigid "balloon" filled with a lighter-than-air gas to give them buoyancy. They have engines to give them thrust and steering control. They have a gondola (or gondolas) suspended below the balloon to carry passengers and cargo. But the materials are different and the gas is different, vastly reducing safety concerns. The power-to-weight ratio is way better. So are the steering controls and the ballast systems, allowing airships to rise, or hover, or reverse, or descend rapidly while staying under control. 

The Hindenburg burnt because it used hydrogen gas for buoyancy and hydrogen is highly combustible. The new beasts use helium, which is inert and non-flammable. Modern airships also use multiple engines that can be aligned in different ways to provide upward, sideways, or downward thrust as required, apart from pushing the airship forward, or reversing it. Essentially these things are as manoeuvrable as a giant quad-copter drone. The ballast control is borrowed from submarine technology. When buoyancy needs to be reduced to descend, helium is compressed and stored in tanks and normal air is pumped into the balloon. When more buoyancy is required, the air is pumped out and helium released back into the balloon. One other thing, an airship does not need to land — it can just hover a few feet off the ground, without expending energy. The ballast mechanism, the steering and engines are automated and computer controlled. 

So, imagine a vessel somewhere between 50 and 80 metres long. It has great agility. It can be zero-emission if it is using electric engines. It could be nearly noiseless, or make about as much noise as a washing machine. It does not need an airport to land, in fact, it does not even need to land. Due to the buoyancy, it can carry heavier loads with less engine power. Apart from carrying cargo and passengers to destinations without airports, these airships can be used for observation and surveillance and their huge balloons also make useful advertising billboards just like their cousins, the blimps.

However, airships are much slower than planes. Most are designed for cruising at 65-70 kmph and the new Goodyear design looks to push that up to about 100-105 kmph. That is the edge aircraft have. Even road and rail transport is quicker. However, the US Defense Department is funding a prototype that can fly at 220 kmph, with a payload of 60 tonnes and a range of 5,700 km. If that design stabilises, there could well be a place for these behemoths, given the other advantages. In that case, the aviation industry would come full circle.