Oct 5, 2010

Hybrid Air Vehicles

Hybrid Air Vehicles are making exciting progress. The LEMV will implement their technology. Horatia Harrod at the Telegraph wrote a good summary of state of the art air ship technology, below.

At Cardington Airfield, just south of Bedford

, two vast corrugated steel hangers tower over the surrounding area. More than 800ft long – the length of almost three football pitches – and 190ft high, they are the heroic relics of the once great British airship industry.

Eighty years ago, two mighty vessels, the R100 and the R101, were housed in these great metal behemoths

; incredible ‘lighter-than-air aircraft’ – with customised silver and crockery, Axminster carpeted smoking rooms and portholed cabins – that were designed to sail noiselessly across the Atlantic like aeronautical cruise ships.

Further down the road, housed in a far less spectacular stack of Portakabins, is a group of engineers who a

re convinced such airships can take to our skies once more. Hybrid Air Vehicles has built a scale prototype of what will soon be the largest flying vessel in the world – a huge balloon made of ultra-lightweight, super-strong polyester on top of a hovercraft landing system. If it works, it could change the future of flight.

Which is why, when you bear

in mind the company’s grand plans, the Portakabins seem so incongruous. They’re only a temporary home but they make the outfit look a bit, well, amateurish. Someone who finds them more than usually annoying is Gordon Taylor. He is the company’s marketing man, a softly spoken but fastidious Canadian in a pink shirt, chinos and a red tie covered with frolicking dogs. A wayward tuft of hair gives him the air of an eccentric professor.

For the past 13 years, Taylor has been fighting a battle with investors, governments and the general public over the perception of the airship. ‘I’ve never seen a more peculiar industry than ours,’ he says as he leads me through the makeshift office on a bright mid-June morning. ‘There are more nutcases…’ He sighs and sips at his mug of Lady Grey. ‘You get what we call “the giggle factor”. People laugh at lighter-than-air vehicles and the guys who make them: the “helium heads”. It’s taken a long time to overcome that.’

The problem, Taylor admits, is that an airship has a deceptively simple, cartoonish appearance. It looks like a blobby thing with a motor, ‘a party balloon with bits on’, as Mike Durham, the heavy-browed, sardonic chief engineer puts it.

‘We’re regularly sent unsolicited proposals telling us how to build airships,’ Durham says wearily. ‘They’re either from 85 year-olds who were once engineers in the pencil business, or little design companies who think they’ve had a brilliant new idea and this is how it should be done.’

This may not sound like a serious problem, but it is. Fred in his shed in Hertfordshire isn’t likely to put forward a proposal to the Government to build a new aeroplane, because big companies like Airbus and Boeing are so well established. But he, and dozens of other mad inventors, will merrily deluge the Government with their ideas for a marvellous new airship. It makes the industry look silly and brings the credibility of the whole business into question, which in turn frightens away would-be investors.

Airship amateur hour is especially frustrating for the team at Cardington because they’re in the process of creating something that absolutely could not be sketched on the back of a beer mat. And Taylor is most particular about the nomenclature of the new development: it’s not an ‘airship’, he says, it’s a ‘hybrid air vehicle’.

‘It’s a new vehicle. It’s a hybrid because we’re combining helium lift, aerodynamic lift, a hovercraft landing system and vectored thrust,’ he says. ‘If you can get beyond the word airship – because that has a lot of history – people think about them differently.’

Taylor struggles to keep the team on-message about the new name: ‘I’m a right pain in the a--- about it,’ he says. Not everyone is convinced that ‘hybrid air vehicle’ will catch on. For one thing, it isn’t snappy and for another, the fundamental points of physics that differentiate it from an airship are beyond the grasp of most mulish lay people. As Dave Burns, the company’s steely-eyed Scottish test pilot, says wryly: ‘If it’s called an airship that’s a lot better than it could be called.’

Whatever you want to call it, the new technology has just won the company (or rather, their US defence contractor ally Northrop Grumman) a contract with the United States Department of Defence to the tune of half a billion dollars. In just 12 months the team at Cardington must build a 300ft-long surveillance vehicle capable of staying airborne for 21 days at a time. It will be known as the LEMV (Long Endurance Multi-Intelligence Vehicle).

The LEMV will hover above Afghanistan at 20,000ft, equipped with the sort of super-powerful cameras that can read a signature on a letter from four miles away. It will be, Taylor says, ‘an unblinking eye’, recording every move made on the ground. In theory, no one will be able to plant a roadside bomb – a device which has claimed the lives of so many British soldiers – without the cameras seeing who did it and, more importantly, where they came from. And, if the LEMV is a success, it could prove to be a tipping point, ushering in a new age of airships.

When I first spoke to Taylor over the phone he gave a seductive account of what long-distance travel might be like in a SkyCat, the civilian version of the airship that the company has designed.

‘Imagine you’re with 400 of your best friends,’ he said, almost convincing me that I had 400 best friends. ‘You go to Richmond Park International. At 11 o’clock on Thursday you get on board the SkyCat200. There are hundreds of staterooms on it and you dinner dance your way across the Atlantic. At two o’clock on Friday afternoon you’re getting off at the East River in New York. You’ve travelled 3,000 miles overnight and there’s no jet lag.’

Ever since the first hot air balloon took off in Annonay, southern France, 227 years ago, the sky has rarely been empty of dirigibles, sources of great wonder and fear to their earthbound watchers. The earliest hydrogen balloon took off from the Champ de Mars in Paris in 1783. When it touched down 45 minutes later in a field beside the village of Gonesse, terror-stricken townsfolk tore it to pieces with pitchforks and scythes.

Next a sheep, a duck and a cockerel were sent skywards, then men. Francois Pil√Ętre de Rozier was aboard the first manned flight in November 1783. Less than two years later, he was dead, plummeting to earth after an explosion aboard a balloon powered by a fatal combination of hot air and flammable hydrogen.

It was almost 100 years later before the first true airship – an engine-powered navigable balloon – lifted off. Henri Giffard, another pioneering Frenchman, attached a steam-driven winch to his balloon in 1867 and set in motion another century of aerial innovation. People experimented with airships powered by foot pedals and propellers and electric motors. Some were killed, but the idea of the airship was always compelling enough to survive.

Count Ferdinand von Zeppelin founded his eponymous company in 1896. With him, the age of the giant airships began and, in Germany, zeppelins became something of a national obsession. They seemed to possess an almost mythic power: like ‘fabulous silver fish’, said Dr Hugo Eckener, head of Zeppelin from 1917, ‘floating quietly in the ocean of air.’

In 1937, though, the spell was broken. On May 6, the Hindenburg zeppelin arrived at Lakehurst, New Jersey, after an Atlantic crossing it had made many times before. However, on this occasion there was one key difference: the United States had refused to supply the swastika-adorned airship with helium, so it was filled instead with hydrogen. As welcoming cameras rolled it was suddenly consumed by fire, stripped to a skeleton in a blazing instant.

A description by one radio reporter went around the world: ‘Get out of the way!’ he screamed into his microphone. ‘It’s burning, bursting into flames! This is terrible! It is one of the worst catastrophes in the world! Oh the humanity! Those passengers! I can’t talk, ladies and gentlemen. Honest, it is a mass of smoking wreckage.’

With this disaster imprinted on the public consciousness, the long winter of the popular airship began. The unofficial motto of the modern airship industry could be, ‘Don’t mention the Hindenburg!’ When talk turns to the crash, Mike Durham dares me to think counter-intuitively: ‘If you don’t write about it, you will set yourself apart as the only journalist to have done that,’ he says.

Gordon Taylor takes another tack, trying to put things in perspective. ‘Just remember that the Hindenburg happened at around the time of the Titanic. But they didn’t have a camera on the Titanic, did they? Think about that when you look around the QE2,’ he says. The Titanic comparison is much loved, and every person I speak to at Cardington makes it.

Even before Hindenburg happened, a long shadow already lay over the British airship industry. Standing by the hangars at Cardington facing south, you see the land undulate ever so slightly, rising to the meanest of hills. On its maiden voyage in 1931, His Majesty’s Airship R101, a colossal vehicle almost 800ft long, barely cleared those hills.

Preparations for the inaugural flight had been hastily made and the ship was leaking large amounts of hydrogen. The R101 managed to make it across the Channel, but then bad weather started to close in. At 2.08am on October 5, when it was around 40 miles north of Paris, it hit high ground and crashed, killing 48 people.

Some 40 years later, a young naval architect named Roger Munk found himself in possession of a book called The Millionth Chance. It was an account of the events leading up to the crash of the R101. (When Lord Thomson, the head of the air ministry, was asked whether he thought anything could go wrong with the airship’s flight he answered, ‘But for the millionth chance, no.’)

Munk died at the beginning of this year at the age of 63, but he is integral to the story of the hybrid air vehicle. After he read that book, in 1971, he went to meet Lord Ventry, who had been a passionate advocate of airships for decades. He sketched out all the problems that Munk would have to conquer to make the vessels viable and that’s what Munk spent the next 40-odd years doing.

His efforts made him the father of modern airships. Today, nearly everyone who works at Cardington talks about Munk’s almost evangelical belief in the technology.

One of those admirers is senior aerodynamicist Ken Nipress. According to Taylor, Nipress is ‘exactly what you might think an aerodynamicist looks and acts like: a boffin’. Slight of face and frame, his thick glasses and thatch of hair make him look like an unusually wiry owl. His manner is that of a typically matter-of-fact Yorkshireman. ‘We like what we do,’ he says, ‘and we think it has got a future.’

In a rectangular white marquee, I am shown that future; a 50ft-long, roughly oblong balloon pumped up with helium. This is the LEMV prototype. A faint plasticky smell comes off the balloon’s synthetic, off-white skin. Every 10 minutes or so a machine that sounds like a vacuum cleaner whirrs into life, topping up the pressure inside the oblong. Lying in the marquee it looks like a sick whale on a respirator.

But, as Taylor and Durham have already made clear: appearances are deceptive. The technology behind the prototype is massively complex. The calculations it takes to work out the flow of air around a hybrid air vehicle are almost too Byzantine for a computer to process.

‘We’ve got an office full of guys who’ve all come out of the aircraft industry and we need every ounce of their brainpower to design these,’ Durham says.

The material used for the ‘envelope’ (the balloon) is ultra-lightweight, UV-proofed, super-strong polyester. The shape is engineered to provide its own lift – the air that rushes over the curved top of the vehicle creates a vacuum that pulls the whole thing up. It flies with fibre-optic controls, which turn physical steering movements into light signals that pulse down thin strands of glass and tell the rudders which way to steer. It takes off and lands with vectored thrust and a hovercraft landing system, so there’s no need for a ground crew to lasso the vehicle back to earth. It’s fuel efficient and, indeed, it could run with virtually zero CO2 emissions.

When I ask Dave Burns, the taciturn test pilot, what it feels like to fly in an airship, he turns poetical. ‘It’s just, it’s a feeling of freedom. And the detail you can see: you can fly over the field out there a hundred times and see different things every time.’

In strong, windy weather, it moves like a ship on a rough sea. Gusts of wind affect it as little as a flea biting an elephant. An airship is a dynamic, almost organic thing. It breathes. Ballonades expel and take in air as the vehicle rises and falls, allowing for the expansion and contraction of the helium. Although EU regulations mean that seat belts are compulsory on the vehicles, it’s a smooth ride.

There’s a niggling worry I have about the LEMV squatting over Afghanistan: surely a giant white balloon will be vulnerable to attack, despite its lofty position? Fortunately, that’s something they’ve thought about a great deal at Cardington. Indeed, they’ve been thinking about it for many years now, because they also designed ships that were to be deployed over Northern Ireland during the Troubles.

At that time they tested a full-sized airship against a range of artillery including a Russian mounted machine gun filled with .22 calibre armour-piercing incendiaries and a SAM-7 surface to air missile. What they learnt was this: the airship is almost invincible to attack. Helium is an inert gas, so it doesn’t explode.

The pressure inside the envelope is so low that when a hole is made, say by a bullet, air seeps out slowly rather than rushing out catastrophically. Missiles need something hard to connect with if they’re going to explode, but an airship is accommodating, not hard-shelled. The material has the flexibility of a plastic bag; make a hole in it and it almost immediately shrinks inwards.

And what of helium, the scarcity of which damned the Hindenburg? If lighter-than-air vehicles were to become a regular form of transport, would any country be in a position to monopolise the new resource? Could helium wars, commanded by squeaky-voiced generals, break out?

Taylor thinks not. Helium is a major component of our atmosphere, but its tiny particles are hard to get a grip on. One day we may develop the technology to extract it from the air (although, Taylor adds, ‘not in my lifetime and not in my son’s lifetime’). Until then there are massive naturally-occurring stockpiles of the gas in the US, Poland, Russia and Canada. Recently, a huge reserve of helium was discovered in the Gulf state of Qatar. Currently, the lighter-than-air market uses only two per cent of all the helium bought in the world. Most of that is used to blow up party balloons.

One other supposed impediment to the development of the airship has been its relative lack of speed. ‘If you go to an air force, you get pilots,’ Taylor says. ‘Pilots like to fly fast things that go zoom and boom.’ But that macho prejudice doesn’t mean there isn’t a market for the stately globetrotting airship. The hybrid air team have speculatively mocked up grand interiors for such vessels, which could be competitors to the great ocean liners.

Realistically, SkyCats would be most useful in the transport of heavy loads – the largest SkyCat can carry up to 200 tons – to harsh environments, like the Arctic territories of Nunavut. ‘The average age there is 21,’ Taylor says, ‘and it’s got the highest suicide rate, highest drug rate, highest sickness rate in Canada by a long shot. They’ve got nothing – this vehicle will save their lives.’

For now, the men of Hybrid Air Vehicles must work at frightening speed to deliver their LEMV to the US government. Taylor expects the team to expand to almost three times its existing size.

Roger Munk used to say that the sheds at Cardington weren’t much use for anything other than airships or giraffe farming. Soon, perhaps, the team he assembled will bring airships back to their rightful home.


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