Daniel Jubb Falcon Rockets BLOODHOUND SSC
By Marcus Tomlinson.
Cundall Manor School N Yorks

Extract:
Mr Jubb is mad about rockets. He began building them out of household objects when he was only five years old, with the help of his grandfather, Sidney Guy. At seven, he began to make model rocket kits, and started launching big rockets with his granddad when he was ten. He was just 11 years old when they set up The Falcon Project, the company that now designs rockets for military applications, as well as commercial and research rockets. I am sure that, within the next two or three years, he will become famous all over the world as the man who designed the rocket for BLOODHOUND SSC, the first car to travel at 1,000 MPH (the record attempt is planned for 2010; the website is a must-see, www.bloodhoundssc.com)

DANIEL JUBB – BRITAIN’S LEADING ROCKET MAN
By Marcus Tomlinson
Daniel Jubb is one of the world’s top rocket scientists. He is only 25 years old, but has already had an amazing life. How many people start their own company at the age of 11?
I was offered an interview with Mr Jubb as part of my work towards the Leaders Award for science, technology, engineering and mathematics.
This makes me a very lucky seven-year old, because Mr Jubb rarely gives interviews. We met at a Top Secret location to talk about his life and work, particularly the rocket he is now developing for the Bloodhound Adventure. He looked very smart, with twinkling eyes and a big smiley moustache. His manner was very polite but relaxed – a gentle man, and a gentleman.
Mr Jubb is mad about rockets.  He began building them out of household objects when he was only five years old, with the help of his grandfather, Sidney Guy. At seven, he began to make model rocket kits, and started launching big rockets with his granddad when he was ten. He was just 11 years old when they set up The Falcon Project, the company that now designs rockets for military applications, as well as commercial and research rockets. I am sure that, within the next two or three years, he will become famous all over the world as the man who designed the rocket for BLOODHOUND SSC, the first car to travel at 1,000 MPH (the record attempt is planned for 2010; the website is a must-see, www.bloodhoundssc.com).
When Mr Jubb was a schoolboy, he liked science best – anything to do with science or scientific experiments. I asked him, ‘if you could travel with any famous person in history, whom would you choose?’ He chose Robert Goddard, the pioneering physicist, rocket engineer and inventor whose work led to NASA and American space exploration.
You might think that Mr Jubb would be keen to become an astronaut, after launching so many rockets into space, but when I asked him if he was planning space travel, he replied: ‘I’m not, and that’s because I’ve seen several rockets explode, and I’d much rather be lighting them from the ground than actually sat on one that was being launched.’ As for passenger space planes, Mr Jubb thinks that ‘the first commercial space flight vehicle will be Burt Rutan’s SpaceShipTwo. They have already flown SpaceShipOne, which was the first sub-orbital space flight that won the X-Prize, and he’s working with Richard Branson’s Virgin group to make that commercial venture. They hope that they will be flying commercial passengers in the next two or three years, so it could be very shortly.’
I wondered what Mr Jubb would have been if he couldn’t have been a rocket scientist, and he told me, ‘I think I would probably be an explosives engineer because I’ve been doing rockets and explosives work since I was fairly young, and they are both very exciting.’ So, what is the most exciting thing he has ever worked on?
‘The Bloodhound project is a very, very exciting project and, although I’ve had a lot of fun with my old rocket projects, this has got to be one of the most interesting, because it’s getting everybody, including all the youngsters, enthused.’ This gave me the chance to ask some questions that had been bothering me since I started following the Bloodhound Adventure. The Bloodhound SSC will be powered by both a rocket and a jet engine. I wanted to know why the Bloodhound rocket is so much more powerful than a Eurofighter jet engine?
‘Well, basically, when we started the Bloodhound project, it was going to be propelled just by a rocket, and the advantage is that the rocket doesn’t need an air intake, and it doesn’t need a lot of the support requirements that a jet engine does; but the problem with the rocket is that it’s very powerful but it’s very difficult to control precisely. It’s very expensive to run, so we decided that we’d have a combined solution of a jet engine and rocket, and the best jet engine that we could find for the job was a Eurofighter Typhoon engine. That produces about 20,000 lb of thrust, but it’s not sufficient to get to 1,000 miles an hour, so we needed a rocket that could produce around 25,000 lb of thrust to overcome the drag of the vehicle and get it to 1,000 miles an hour. So we designed the rocket from the start to produce 25,000 lb of thrust … it’s not that the rocket per se is more powerful, but it’s been designed to get the total thrust to 45,000 lb.’
I asked Mr Jubb if they couldn’t have had a SCRAM (supersonic combustion RAM) jet engine?
‘The SCRAM jet engine is very new technology.  They’ve been testing some SCRAM jets in free flight vehicles, both launched in the US and launched in Australia, but at the moment they don’t produce that much more thrust than they produce drag, so they’re not that effective, particularly at ground level, and I don’t think at the moment we’d be able to get one to work. I should also mention that SCRAM jets only work at much greater speeds than we are talking about, Mach 6 and above.
The Bloodhound website has a brilliant video showing a computer model of the car travelling faster than a bullet. I watched it with some friends, and we wondered why there is one rocket on top instead of, for example, one on each side of the jet engine?
‘That’s a very good question. We’ve experimented with various different configurations for Bloodhound. The guys at the design office at Bristol and at Swansea University who are doing the aerodynamics have moved the rocket and the jet engine around to see which configurations worked best. We looked at a single rocket, a twin jet arrangement, and a rocket and a jet, but basically the jet is a very heavy item; it weighs around 1,000 kg and it’s very important that we sat that low on the ground. Also, because it’s a larger diameter than the rocket, it had to fit within the vehicle body profile, and it fitted better at a low height with a small diameter rocket sat above it. So, it’s putting the rocket and the jet in the best configuration to give the minimum amount of drag.’
The Bloodhound rocket is the largest one of its type ever built, and the team’s goal is to make it safe and reliable. Have they achieved this? They hope they have, but won’t actually find out until they start to do multiple firings of the big rocket. The rocket on the car will be eighteen inches in diameter, but they have been running their tests on a six-inch diameter prototype. Amazingly, Mr Jubb went on a very long trip just to collect the six-inch chamber and bring it to the interview for me to see.
There are three main types of rocket:  solid fuel, liquid fuel and hybrid. This one is a hybrid; hydrogen peroxide is the liquid oxidiser and rubber is the fuel. I understood that the liquid makes the rubber burn, and that if you shut the supply off the solid fuel should stop burning, but I wondered if it might just keep going.

Mr Jubb explained: ‘The peroxide is coming in at the top.  As it passes over the catalyst pack it turns into steam and oxygen, and it’s the oxygen that’s being used to assist the fuel in burning. Now, when we stop that supply most of the combustion stops, but you’re quite right, the fuel grain can carry on burning, so we also have a second point at the top of the rocket where we can inject some nitrogen gas which will purge any remaining peroxide out of the catalyst pack and then that nitrogen will put out any remaining flames on the rubber fuel grain. So, that stops the rubber from burning.’
Later on, Mr Jubb showed me some videos he had brought of test firings, and we watched an inefficient rocket in slow motion:  you could see the fuel grain igniting, and a short flame that kept going a little after the end of firing. We also watched a spectacular video of a successful firing and Mr Jubb talked me through the action:
‘What’s happening there is, we’ve got the hydrogen peroxide tank at the back, and we’re using nitrogen to push the peroxide into the rocket. You see when it starts there’s a little bit of steam and that’s as the peroxide is contacting the catalyst pack, turning it into steam and oxygen, and that is generating enough temperature to light the fuel grain, and then once the fuel grain lights we turn the valve into the fully open position, and then you see the big plume from the rocket.’
There was also a clip of a rocket that generated such a high temperature that it burnt right through the case. This told the team that they had to make changes to the insulation inside the rocket.
A very interesting thing happens when these rockets are fired. The flame produces beautiful patterns called Mach diamonds. I had never heard of these before. We looked at a photograph of a rocket as Mr Jubb explained: Basically the mach diamonds are produced when the high velocity gas in the exhaust begins to interact with the air, the pressure difference causes local variation in the gas pressure and velocity. The shock patterns are visible because of brightly glowing particles (luminescent species) in the exhaust.
The rocket part of the project is going so well that Mr Jubb has managed to produce 15% more thrust than was asked of him, but what is happening elsewhere in the Bloodhound Adventure?
‘The design team, which is based in Bristol, is finishing the final design of the car at the moment, so that we can start to build it. They are currently working with the team at Swansea University to get the final aerodynamic profile of the car worked out, and then the engineers can start designing the internal parts like the chassis, and the wheels, and the fuel tanks, and so on. Hopefully, we should be able to start building the car in the next few months.’ Testing will probably be in the UK, on a runway somewhere, at fairly low speed runs just to test the general operation of the car. They haven’t yet decided on the location for the actual record runs, but it will probably be either the Verneuk pan in South Africa, which is an alkali dry lakebed, or the Newfoundland Basin, a salt flat in Utah. They hope to go out there for the first time in 2010.
Being kind and generous, Mr Jubb finished the interview by giving me a carbon fibre nose cone to use when I start building my own rockets, but I shall keep it as a reminder of the day when I met a very special man.
Edits from Daniel Jubb
*On the subject of mach diamonds, this is a very complex point to get across. Further information is available at the following site:http://www.aerospaceweb.org/question/propulsion/q0224.shtml