Ariane running hot

The access road to the testing site is closed. A nearby sign shows the warning ‘Danger Zone’ in large letters. Rocket engine tests are about to start. At temperatures more than 100 degrees below freezing, liquid oxygen and hydrogen flow through separate tubes towards the combustion chamber. As soon as the correct temperature is reached, it takes just seconds:
the two liquids combine, one pyrotechnic detonator ignites the mixture, while two others start turbopumps and turbines. The engine roars. In the combustion chamber, the temperature soars to 3,000 centigrade as the jets glow orange and red. And then, 10 minutes later, the test is over.

“No gas is allowed to leak out between the tank and the combustion chamber. Otherwise, there’ll be an explosion”, warns Ralf Hupertz, engineer at the Institute of Space Propulsion, part of the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt – DLR). So far, this has never happened. For many years, HDI Global SE has managed risk protection at the rocket test site with a specific solution under its technical insurance division.

After the tests, engineers analyse the large sets of data produced. “We look for anomalies that we need to address before the next test,” says Ralf Hupertz. The data is then passed on to the client – the Ariane Group. During the last 50 years, the Institute in the small village of Lampoldshausen has become a unique European research and test site for rocket engines. Currently being put through its paces is the new upper stage of the Ariane 6 launcher. This required a vacuum to be created in the test cell as the Vinci upper-stage engine won’t ignite until Ariane is around 150 kilometres in space, giving the rocket a second boost. The new launcher is expected to blast off from the Guiana Space Centre in French Guiana in mid-2020, carrying weather and communications satellites.

Further information on Ariane and rocket testing can be found at dlr.de