#1 Skylon: Bond's mission to replace rockets with spaceplanes
Posted: Wed Apr 30, 2014 1:01 am
Since I watched it on Youtube recently, here's the Three Rocketeers BBC documentary referenced in the article:Wired UK wrote:"As young as 12 I was building my own rockets," says Alan Bond, inventor of the Skylon spaceplane and Sabre, the revolutionary engine that could herald a new era of space travel.
"[But] only really good ones from about 16 onwards," he adds, with a smile.
We are standing in a hangar at the Culham Science Park near Oxford, surrounded by the fruits of a lifetime of engineering.
A large model of the Skylon spaceplane stands behind him. A sleek black aircraft, the Skylon is a glimpse of the future of space travel. To his left a cross-section of the Sabre -- Synergistic Air-Breathing Rocket Engine -- the engine that will power the Skylon; and on a blue table far on his right, part of the manufacturing process for the Sabre's unique heat exchanger, a secret feat of engineering that cools air travelling at Mach 5 from 1000 degrees Celsius to -140 degrees Celsius in just one hundredth of a second.
You can photograph everything except the blue table, his press officer tells me. "The technology […] has been very hard won," explains Bond later.
For the last 30 years, Bond has faced not only technical challenges that seemed insurmountable, he has also fought the obstinacy of the British government, faced the boot heel of the Official Secrets Act, circumvented patents he originally wrote in order to continue his work, and spent over a decade building up a rocket engine company on a shoe string budget; "a very frayed shoe string," Bond points out.
As a teenager, Bond built rockets "under questionable circumstances of legality". Throughout his career he has had to "duck and weave a lot" to develop his ideas. Now 69, he is finally beginning to see his dreams become reality.
In November last year, the first live test of part of the heat exchanger was a success. The European Space Agency has given him their stamp of approval and in July of this year the UK government agreed to fund £60m towards a £250m development programme over the next four years, with the rest of the money to come from private investment.
"I guess I'm a bit pig-headed," says Bond. "I thought if I could continue long enough, eventually somebody somewhere would take notice."
People are indeed starting to take notice, the UK government has put a multi-million bet on this man changing space travel, and decades of work are finally being vindicated.
Out in the Oxfordshire countryside, about an hour from London, sits the Culham Science Centre. A former military airfield, it opened in 1944 towards the end of World War Two, and was later taken over by the UK Atomic Energy Agency. It is now a hub for nuclear fusion research: two international experiments Jet and Mast -- running since the 1980s and 1999 respectively -- explore the potential of nuclear fusion reactors and lay the foundations for future energy sources.
In the middle of the park, in a grey single-storey building, is Reaction Engines Limited (Rel), the company Bond founded in 1989 with his colleagues Richard Varvill and John Scott-Scott -- a 2012 BBC documentary called them "The Three Rocketeers".
The trio came here to lick their wounds and restart anew after the cancelling of the predecessor to the Skylon project in 1988: Hotol.
"[We] managed to pull Reaction Engines together and rescue what we had done [with Hotol]," says Bond.
Hotol -- Horizontal Take-Off and Landing -- was a flawed spaceplane that was to be Britain's last chance to claim a place beside space-faring nations like the US, Russia and others.
Conservative Minister Kenneth Clarke, then Trade and Industry Minister in the Thatcher government, pulled the plug on government funding in 1988 and so ended Britain's pretensions to being a space-faring nation.
"We were going to be a nation that was going to use space but not actually develop any of the technologies to get there," says Bond.
The team had next to no money and no support from the UK government. When Bond had tried to continue his work in Europe, the Official Secrets Act was slapped on to the whole Hotol project, so that the sensitive aerospace technology couldn't be taken abroad.
Despite these obstacles, the team had a wealth of ingenuity and a burning belief that if humanity is to conquer space, it has to find a better way of getting there than simply lighting the fuse on expensive fireworks.
"Expendable rockets can never deliver a credible transportation system," says Bond. "It is just too labour intensive to build a vehicle of that complexity and then throw it away after one flight."
Every launch carried out since the dawn of the space age has used single-use multi-stage rockets -- the rockets shed sections, using up different stores of fuel as they moves from stage to stage. All that eventually reaches space is a tiny module -- the rest of the rocket is discarded.
Since the mid-1960s, Bond has doggedly pursued the idea that this is a fundamentally flawed way of getting into space, for a number of reasons:
The lead times are measured in months and years, instead of days and weeks, "because [your rocket] has to built from square one" for each launch; they're single-use, you get none of the value for money that comes from reuse; and on top of all that, "there is no opportunity to find errors before the thing flies", as the Russians most recently discovered 2 July, when an unmanned Proton-M rocket crashed seconds after launch.
The perverse result of this is that the equipment we put into space has to be inordinately reliable. If a satellite fails, it costs hundreds of millions of pounds to get up there to fix it, and you would have to wait months and months in any case.
"The characteristics of the whole thing are completely wrong," argues Bond. "Quite frankly, it's not rocket science to recognise that's the situation."
Of course, the reason why rockets are currently used is, despite their flaws, it's a proven technology.
But Bond dreams of a future where a satellite operator can pick up the phone on Monday and have a repair team in space by Friday. He wants to bring the economics of the aviation industry to the space industry. To do that, we need to stop thinking about space rockets, and start thinking about spaceplanes.
"It's a technologically demanding problem," he admits. "But I think we've cracked it."
Enter Skylon, the vehicle that could make cheap and easy access to space a reality. If built it will enable humans to fly to space in one jump and then fly down again, ready for reuse, again and again.
Its body is taken up mostly by hydrogen fuel tanks, meaning that once empty, it's much lighter on rentry than the Space Shuttle was, meaning it heats up less than the Space Shuttle did.
What makes the journey into space possible is the Sabre -- an engine that's a cross between a hydrogen-burning rocket and a jet engine. On the ascent to space, it pulls in oxygen from the atmosphere, like a jet engine. Once in space, it uses stored liquid oxygen, like a rocket.
To cool the high-speed air coming into the engine, Bond and his team had to invent a pre-cooler that could not only drop the temperature from 1000 degrees Celsius to -140 degrees Celsius in the space of a fraction of a second, but also not frost up in the process.
It's a problem that they worked on for 15 years, sometimes in their kitchens -- "if you're going to work with frost, you need a source of water and ice, and the kitchen freezer is the place you go for that" -- before finally cracking it in 2004.
Exactly how they cracked it that is a closely-kept secret -- Bond will only say that "they look at the liquid hydrogen as a way you can reject waste heat from a the engine" -- but the heat exchanger itself is a testament to British engineering. Thousands of miniscule tubes, with walls only 40 microns thick, carry cooling helium at a pressure of 200 atmospheres (a standard road bicycle tyre is around 7 atm).
Over the next four years, a £250 million programme will bring the engine's development to the stage where it would be ready for manufacture. £60 million of that will come the UK government, which, as Bond sees it, has finally recognised the importance of long-term investment in space and manufacturing.
In 1988, when Hotol was cancelled, it seemed like this moment would never arrive. A joint project between Rolls-Royce and British Aerospace, the Hotol began development in 1982.
"To discover that the UK was considering doing something really innovative in launch vehicles […] was a really exciting moment," says Dave Parker, head of the UK Space Agency. "[But] the original Hotol concept […] was not buildable at the end of the day".
Hotol had its engines at the back of the plane, which resulted in a centre of gravity problem that made the design difficult to control. At the time, Bond was yet to crack the frosting problem in an efficient way.
"If there was all of the money to build Hotol back then they [Hotol's backers] would have stopped quite quickly on realising it didn't work," says Parker.
Kenneth Clarke, Trade and Industry Minister in Thatcher's government, now a minister without portfolio in Cameron's government, made the decision to stop funding Hotol in 1988. "The Government of the day took its decision on the basis of the national interest and the risk reward ratio involved at the time in the 1980s," he said in a statement to Wired.co.uk.
However, the decision was a personal blow to Bond. "I was fairly devastated," he says. "I wrote to every influential person that I could think of to say, don't do it. But unfortunately the avalanche started and the whole project got buried."
He still holds some bitterness towards the man who made the decision to end the project: "I think there's nothing positive or constructive that I could say about Kenneth Clarke."
But in the 25 years since Hotol was cancelled, Bond has managed to solve the problems that crippled Hotol. A new government, one that ironically Kenneth Clarke is also a part of, is supporting a technology it previously abandoned.
"We've come through a very cynical age in the 80s and the 90s," notes Bond. "All of a sudden our future doesn't lie in providing financial services to the rest of the planet until the Sun goes out."
Its raining when we reach Reaction Engines' test-site in Culham. Beneath a protective canopy, a Viper engine is attached to a test pre-cooler module.
When Reaction Engines began its work in the 90s, test-sites were unaffordable luxuries. Computer analysis and modelling sustained their investigations. "We've been very fortunate, in that the development of this project has been at the same time as the computer revolution," notes Bond. "[…] We've gone from very lean years, with next to nothing, now we're actually in quite good shape."
There is still some scepticism about the project, but independent oversight from the European Space Agency has helped to assuage some of that.]; "You need that seal of approval from an acknowledged organisation like ESA," says Dave Parker.
A hypersonic airliner has been talked up as a potential use for the Sabre. An EU-funded study called Lapcat looked into using a derivative of the engine that didn't have space rocket capabilities. Bond admits that such applications are not his primary aim, and talk of a passenger jet has led to some comparing Skylon unfavourably to Concorde. It's a comparison that Bond rejects utterly.
"It's pretty much the Concorde situation in reverse," he says, arguing that current launcher technology represents Concorde-esque economics. "It's the people mover we're bringing in, it just happens to look like Concorde."
For Bond, this journey has been much more than a personal mission over adversity or a simply an engineer's supreme desire to beat the challenges set by nature. For this man, a "maverick" who is a "link to that first age of space in the UK" in the words of the Head of the UK Space Agency, this journey is about the salvation of the human race.
"What is absolutely clear to me is that the human race and its petty squabbles are confined to one piece of debris near a fairly ordinary star," he says, echoing Carl Sagan's Pale Blue Dot comments. Bond fervently believed that without easy access to the abundant resources of space, the human race can never sustain Western standards of living and a growing global population.
"Getting into space is not just that long-haired scientists do as a bit of fun," he says. "It's something that's absolutely crucial to the continuing progress to the human race."
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This is what I truly wish was the successor to the space shuttle. While there's a little jealous patriotism at work on my part here, I am glad to see that this will likely make the ESA very quickly a strong partner in space projects and research.
Hilariously enough, unless Russia has plans to seriously update the Soyuz, they're going to get left in the dust by both the ESA and NASA here shortly. NASA may not be working on a true single stage to orbit plane like the ESA is, but the Orion's first test flight is slated for this December.
The design for the plane itself, and the work that went into designing all of it is just awe-inspiring - particularly the heat exchanger. The fact that it takes incoming air in the thousands of degrees and cools it down to -100 degrees in less than a hundredth of a second is... just cool, even for non-engineering nerds such as myself.
The video goes over the Skylon's history and builders with more detail, and is fascinating to watch besides.