| Space bid for world's biggest manned balloon |
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 The biggest manned balloon in history, as tall as the Empire State building, is being completed in the United Kingdom in readiness for an attempt to break the world altitude record by reaching a height of almost 40 kilometres (25 miles).
The project is being sponsored by QinetiQ, which is the UK's largest independent science and technology company, and it is hoped to make the historic flight some time in the next few months. No one has attempted to break the altitude record for 40 years despite it being described as "one of the greatest possible aviation adventures."
 The balloon, known as QinetiQ I and being built at the mission's headquarters in Glastonbury, western England, is made of polyethylene of the same thickness as a household freezer bag. The polyethylene has been manufactured with special additives that will enhance its performance in a hostile environment where temperatures may drop down to minus 70 degrees Celsius. It will have a volume of 1.2 million cubic metres and take two hours to inflate.
QinetiQ says the balloon needs to be so large because it will stop ascending at the height where the mass of the balloon is equal to the mass of the air it displaces. There is so little air at 30,000 metres and above that the balloon needs to be huge in order to displace enough air to give it the necessary lift.
 QinetiQ 1 will be manned by two Britons, Andy Elson, an aeronautical engineer and experienced balloon pilot, and Colin Prescot, a commercial balloonist and adventurer. Mr Elson also designed the balloon to go into space and Mr Prescot regards the mission as the ultimate professional challenge and a historic addition to the United States space programme flights of the 1950s.
During the attempt by QinetiQ I, images captured in space from the balloon will be sent back live to earth. The flight platform that will house the pilots has undergone a series of tests on the southern England coast. These included floatation tests designed to check buoyancy of the craft in water and how well it will right itself if tipped over. When it returns from the edge of space at the end of the flight, the platform will splash down into the Atlantic Ocean.
More dramatic were a series of drop tests from a crane which saw the 1,500 kilogram platform splash down
as if it were landing in the sea.  Experts started with a drop from three metres to test the platform splashing down at an equivalent speed of just 7.6 metres a second. It was eventually dropped successfully from six metres, reaching 10 metres a second as it entered the water.
In an emergency landing, the pilots will remain seated in an emergency position and will descend under parachutes attached to the platform. Only as a last resort will the pilots leave the platform and descend using personal parachutes.
Source: London Press Service, web site at:
http://www.london.press.net
Published
on 9th September, 2002
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