Posted July 30, 2015

Rockets made in Holland

If you need a rocket sometime soon, don't go straight to SpaceX. Here's a small Dutch company that's developing its own rocket. The company is called T-Minus and the rocket is especially designed to bring research hardware into the upper layers of the atmosphere.

One of the founders of T-Minus is space engineer Roel Eerkens, who did some serious rocket science when he was still a student at the Technical University of Delft. 'I helped design and launch a number of rockets. One of them, Stratos-1, reached an altitude of 12.5 km in 2009. That's still the European record for amateur rockets. I hope it will get broken soon - by guys from Delft.'

Eerkens and three of his buddies found out that the techniques they used were so advanced, they could hire themselves out to professional space organizations like ESA. For ESA they did a Cansat launch. A Cansat is a probe as small as a can of soda for educational purposes. Cansats typically reach an altitude if a few kilometers. As the Cansats fall back they can do all kinds of measurements, depending on what sensors have been built in. Now one of the products T-Minus has on offer is a Cansat launcher which can deploy 6 Cansats simultaneously.

This kind of work has given our company some time to get going,' says Eerkens. 'Now one of the things we do is consultancy: helping other companies solve space engineering problems. This may concern propulsion but we also do assembly, integration and testing. We're involved with InSight, a NASA mission to Mars that will land in 2016 and investigate Martian soil by penetrating into it to a depth of 3 meters.'

Assignments like this enable T-Minus to have people work on developing the DART, a small rocket that can reach an altitude of 120 km. It's an entirely self-financed enterprise.

Eerkens: 'Balloons can't go higher than about 50 km. Satellites can't go lower than 200 km. The region in between we call the ignoresphere, because it's hardly investigated.' This uncharted area is relevant for both climate research and spaceflight, because it borders on both the atmosphere and outer space.

The DART is is indeed shaped like a dart and it is designed to be simple and cheap. For instance, booster and payload compartment get separated when the booster part burns up and decelerates by gravity and friction. The payload compartment keeps climbing in 'free fall' until it reaches maximum altitude. Then a parachute is deployed to make descent time - equals measurement time - last as long as possible.

A DART test flight in the Netherlands in september went smoothly. But due to restrictions in Dutch airspace a height of only 2 kms was reached. 'For a full scale test, something the space business needs to see, we will  have to launch from a professional launch site, for instance in Norway, Sweden or Spain,' says Eerkens. In a year or two T-Minus expects to sell its first DART. He estimates the market to be about a hundred DARTs a year.

About Herbert Blankesteijn

Herbert Blankesteijn is a technology journalist from the Netherlands who has written for many prominent Dutch newspapers. He presented and directed television and radio programmes and has 10 books to his name. Herbert is interested in nascent fields such as 3D printing, drones, robotics and the private space business.