Bring Back Airships

I have a confession to make: I am one of those nut-job engineers who advocates for the return of airships as a means of travel.

Wait! Before you roll your eyes and commit me to an asylum, hear me out.

Comfort

What prompted me to have a whinge write a post about this is my recent trip to the UK. I have just flown from Australia to the UK for a three day meeting of the Square Kilometre Array Signals and Data Transport consortium. I spent a total of 18 hours in the air, with one stretch of 11 hours cooped up in an aeroplane. I am a very restless person and being confined to a seat for long periods sends me absolutely spare. Comfort is the main factor for me in my support of airships.

The heyday of the airship was the years between world wars one and two. This was the time when the largest aircraft ever built circled the globe, carrying passengers in comfort. The airships of the time had cabins for the passengers, a dining room, a games room, a promenade deck, and even a smoking room. If we were to bring back airships, due to their low speed compared with jet aircraft, passengers would have to be accommodated in similar levels of comfort. You could not ask someone to stay in the same seat for days. There would be room to move around and stretch, and my mental stability would be somewhat preserved.

So, now that my main reason for wanting to ride in an airship is out in the open, let’s consider the other arguments for and against airships.

Cost

Dining rooms and promenade decks and multi-day flights sound like a recipe for extremely expensive air travel, and indeed, in the 1920s and 1930s airship flights were pretty much the most expensive way to travel. However, I argue that with modern materials and technology the cost of a ticket on an airship could be comparable to an economy seat on a commercial jet-liner.

Since the airship is held aloft by the buoyancy of its gasbags, its engines do not have to be as powerful as a jet-liners. Also, the large surface area of the airship is a convenient place to mount solar panels. Airships could be solar powered and thus have minimal fuel costs.

Admittedly, I have not actually done any calculations to analyse surface area vs power production vs drag, but oh look a distraction!

Helium is expensive and is a non-renewable resource, so I suggest that modern airships use hydrogen. This would be almost free if the airship company uses solar power to produce the hydrogen from water by electrolysis.

Safety

“Wait! Hydrogen?!?!” I hear you exclaim.

Despite what the most common depiction of airships would have us believe, using hydrogen to lift the ship is not that unsafe. The loss of the Hindenburg was the Zeppelin company’s first civilian accident. The Zeppelin company was the most experienced operator of airships and had flown tens of thousands of passengers millions of miles in the few decades it had been in existence without incident. The only other times Zeppelins caught fire was during WWI when the Allies deliberately pumped them full of ammunition expressly designed to set Zeppelins on fire. While the Hindenburg disaster was a tragedy, accidents such as that have not stopped us using any other form of transport.

Of the 97 people on board the Hindenburg, only 35 were killed in the accident. That’s a nearly 64% survival rate. Some of those deaths were due to passengers jumping out of the burning airship when it was too high off the ground. The Hindenburg took about 30 seconds to burn, and because it was lighter than air, it crashed slowly. Survivors of the accident made their escape when the Hindenburg settled to the ground.

Even by the standards of the time, the Hindenburg was not a particularly large disaster. Contemporary reports pointed out that commercial aeroplane crashes also occurred and killed similar numbers of people in each crash, and wondered why lighter-than-air aviation had slipped so slow in public opinion. Even today we still accept that there is some risk in flying.

It would be wrong to argue that it would be insane to fill a flying machine with something so inflammable, since we do so every day. Fire is one of the most feared situations in aviation because the planes are loaded with tons of highly inflammable jet fuel. Fires on jet-liners do happen, and when they do, they can take hundreds of lives. A hydrogen fire is less disastrous than a liquid-fuel fire since the buoyancy of hydrogen draws it up and away from people and structures. This is one of the reasons the Hindenburg disaster was relatively survivable. The diesel the Hindenburg carried continued to burn for more than half an hour after the crash.

Today, we also have modern technologies, such as flame-retardant materials and fire-fighting systems, that would significantly reduce the risk and consequences of an airship fire. We could even use a double gas cell design developed by the Hindenburg’s engineers, in which a primary hydrogen gas cell was contained inside a protective helium envelope.

Speed

OK, I’ll admit that we have a problem here. But it is not as bad as you think. Airships look slow because they are high up in the sky, but they are actually pretty fast. The Hindenburg and Graf Zeppelin both had top speeds of around 135 km/h. To make the 17,740 km trip from Perth to London at this speed would take… 5.5 days… Ah… Oh dear.

Since a trip from Perth to London currently requires you to spend around one day in transit, I think that a three-day Zeppelin ride would not be unacceptable. This would require the airship to cruise at 200 km/h. This is a considerable increase over the Zeppelins of the 1930s, but might be achievable with modern technology.

Improved engines, greater understanding and modelling of aerodynamics, and low-drag materials would allow a modern airship to fly faster. Modern construction methods and materials would create a lighter airship that could fly higher-up where the drag of the atmosphere is reduced and the airship could move at higher speed. A cruising speed of 200 km/h would be a challenging, but not impossible goal.

Weather

Adverse weather would be a significant problem for airships. Because they would fly lower than jet-liners they would not be able to fly above bad weather the way airlines do currently. Modern meteorology, thanks to satellites and radar, would allow airships to navigate around dangerous weather, but this would inevitably cause significant delays.

However, maybe a modern airship would operate at altitudes comparable to a jet-liner and so not suffer from this problem.

Communication

While holiday-makers might not mind a three-day cruise, those, like myself, who are travelling for business would object to wasting so much time in transit. But, as long as the airship had good internet access, the time could be spent working and would not be wasted. I would have spent the trip writing and reading papers, preparing presentations, and relaxing in my bunk watching YouTube videos. Airlines already offer some slow and limited internet access, but airships would have to offer large amounts of high-speed broadband. As projects to deliver high-speed internet world-wide, such as Google’s project Loon, Facebook’s Internet.org, and SpaceX’s internet satellite program, come into operation, convenient internet access on aircraft will become ubiquitous.

Infrastructure

A common argument for the return of airships is that they do not need runways, and so can operate in more remote and diverse regions than jet aircraft.

They look pretty

Come on. You’ve got to admit that airships drifting serenely overhead would be pretty cool to see.

 

So that’s my argument in favour of airship travel. If you have an idea or information to add for or against this, I would love to hear about it in comments.

Alternatively, we could double the speed of airliners, making the trip much more bearable. But do it quickly. I’ve just checked-in for my flight home.