Tests on engines of Skylon space plane have begun

Testing has begun on the engine system of the groundbreaking new Skylon plane, which relies on pre-cooler tubing supplied by Fine Tubes Ltd. Developed by Reaction Engines, the Sabre engine combines jet and rocket technologies and will be able to take off and land from a runway and fly out of the atmosphere into space.

Like the Sabre engine itself, the tubing in its heat exchanger is an engineering marvel. “The pre-coolers need thousands of metres of very thin tubing,” explains Paul Mallett, aerospace specialist at Fine Tubes. “So we specially designed a tube for Reaction Engines with less than 1mm outer diameter and a wall thickness of just 40 microns - that is about half the size of a human hair.”

Demonstrations of the Sabre engine have begun, after the UK and European space agencies gave the project the green light earlier this year. Skylon is scheduled for launch in 2020 and will operate at 1/50th the cost of conventional rockets, providing reliable, reusable and inexpensive access to space for cargo transport and even space tourists.

The engine first cools, then compresses air from the atmosphere which it burns with hydrogen to provide thrust, using a mixture of hydrogen and oxygen to propel the plane into space. Fine Tubes has been instrumental in producing key parts for the pre-cooler system, which cools the air for the engine intake. It’s a breakthrough piece of design within Sabre. According to Robert Bond, the company’s corporate programmes director, Fine Tubes took on an enormous challenge with the pre-cooler tubing.

“No one else has managed to create heat exchangers like this before and the specifications for the components are very demanding. The tube itself is made from a nickel alloy that is very resistant to temperature. The quality of the tubes is crucial to the success of the project as they must have the integrity to withstand extremely high pressure helium,” says Bond. “There are a few other companies which produce the kind of high technology tube we need but the Fine Tubes product is extremely high quality, meeting all the project specifications. We are very pleased with its performance.”

Manufacturing tubes so small that could resist damage and the huge temperatures and pressures involved, was a challenge in itself. In addition, engineers need to be able to pump cleaning fluid through the tubes. Finding the solutions has been incredibly rewarding. “It is immensely satisfying to collaborate on such a high-calibre project and contribute to a development of global importance,” says Paul Mallett. “We have very much enjoyed working with Reaction Engines over the past 10 years and are looking forward to the next 10, at which time the Skylon will hopefully be ready for its first launch.”

Watch this space for further updates on the project.