Launch Campaign

On Monday, the 6th March 2017 early in the morning, the RaCoS team travelled to Esrange Space Center in northern Sweden, which is located next to the city Kiruna. The first week was planned for unpacking the equipment and preparing the experiment for final communication tests. These tests went very well for REXUS 22, so we had some spare time, in which we went cross-country skiing through the wonderful snowy landscape or generally just enjoy the beautiful view.
After the first week, on Sunday, some of our team visited the national park Abisko, an astonishing landmark of northern Sweden known for its famous mountain formations.

Wonderful view

In the evening, all teams spent their spare time together. We had the possibility to drive snowmobiles over a frozen lake and through the woods. After all the exhilarating driving, we relaxed at the campfire and had some hot dogs, before we topped things of with driving dog sleds.
On Wednesday REXUS 21 launched successfully after one cancelled launch the day before, caused by bad weather conditions. Our whole team watched the spectacle from the radar hill. Thereafter the REXUS 22 rocket had its roll out, which means that the fully assembled sounding rocket was rolled out of the building “The Church”, where all teams worked on their experiments the days before. Then it was horizontally attached to the launcher.

Roll-Out of REXUS 22

Thursday morning we had our own test countdown, in which two of us had to refill the pressure tank in a “late access”. Luckily no teams had problems during test countdown, so we concluded our final milestone, the “Flight Readiness Review” without problems.
Because of the good weather conditions, it was decided to start the countdown shortly afterwards. Three members of RaCoS were in the Science Center to command and operate the Ground Station, while the other two went to the radar hill from where they had a great view of the lift-off. The rocket launched right on time, with no delays in the countdown and our system performed as expected during flight.
Later on, the payload was recovered by helicopter and we got our experiment back the same day for further data analysis.

With the team

On our last day, we had to pack everything and prepare for departure. In the afternoon, first results of all experiments from REXUS 21 and 22 were presented.
The Campaign Dinner in the evening was a marvelous event to finish our two weeks at Esrange Space Center.

Check out some more pictures in the gallery in the Launch Campaign section!

End of Launch Campaign

Today it’s our last day at Esrange Space Center. We had two really incredible weeks and a super launch. Tomorrow we will travel back to Würzburg, where we will analyse the data more precise in the next few weeks.

Stay tuned for the whole launch campaign report, which will be posted here.

Start of Launch Campaign

Yesterday the whole RaCoS-Team travelled from Würzburg via Copenhagen and Stockholm to Kiruna and drove all the way out to Esrange Space Center in our rental car. The trip was exhausting but the launch and all the things connected to that makes it worthwhile 😉

The first week all teams will prepare their experiments here in “The Church” and conduct final tests before the hot countdowns next week. Stay tuned on Facebook and Twitter where we’ll post updates as well as occasionally livestreams.

Bench Test

Tuesday, 17th January 2017 two of us made their way to Oberpfaffenhofen early in the morning to visit the DLR for our bench test.
On Tuesday we unpacked our equipment and prepared for an air-bearing test. These activities included work on the battery platform that we use on mobile RaCoS tests and counterbalancing the setup, so that we can test on a balanced system (e.g. eliminating unwanted influences).
Later that day the first short test run commenced and looked promising for the tests on Wednesday.
Wednesday two more team members arrived and we could start an array of air-bearing tests to look more closely at our system performance and operation of the control algorithm. We made a video that day about the air-bearing tests, which you can find on our
After we were done with these tests we had a comm check test with the other experiments on REXUS 22 in which we all were connected to the service module and checked incoming and outgoing signals. That test concluded the day.

Coming back on Thursday we had the ‘real’ bench test scheduled. First in an open configuration were all experiments were electrically connected to each other but not mechanically. After completing and successfully finishing that test we had some time to prepare for the next and final stage of the bench test were all experiments also get mechanically attached to each other in the configuration which will fly to space in March this year. In the afternoon this test was successfully finished and ended the official activities at DLR/MORABA.

On our last day we came in early to pack RaCoS and the necessary equipment for the launch campaign in Sweden in containers, ready to ship to Esrange. Then we tidied up our workstations, said everybody good bye and made our way back to Würzburg.

Thanks again to all other teams and the people responsible for the great time at the bench test!
We will see each other at the launch campaign and can hardly wait.

For some impressions of the bench test visit our gallery at
Bench Test and see among other things DLR and the MORABA-Lab from the inside.

Integration Week

Early in the morning, on Monday, 12th December 2016, four of us were headed for Bremen to participate in the ITW (Integration Week) and to complete our EAR (Experiment Acceptance Review) at the ZARM’s drop tower.
The first two days we unpacked and prepared our experiment. We performed some smaller tests, for example measuring the thrust of our system with different nozzles and testing the performance of the controller with our turntable.

Tuesday evening, we visited the Christmas market of Bremen, where we met some other REXUS teams. Afterwards we had a nice walk through the city back to the hotel.
The next morning we had our EAR. The experts inspected amongst other items the electrical and mechanical setup. We passed the review with great success.
Thereafter we prepared the experiment for a vacuum test. First we performed an initial test at atmospheric pressure before evacuation of the 122-meter-high drop tower. Depriving the tower of all air took longer than an hour. More than enough time to have pizza before testing the thrust of our system in vacuum environment. The results were amazing!
On Thursday morning our system was in for a rocky start as it was time for the vibration test. Luckily, all components continued to function even after all the shaking about. Scheduled next was a payload integration test with all other experiments of REXUS 22. Every experiment was switched on and off a few times to identify problems between the setups.
On the last day we were allowed to perform another vacuum test. This time with a focus on controller performance. Instead of having pizza during evacuation time we visited the top of the tower and the catapult and learned more about the facilities. The test was successful with the spin rate of the test dummy reducing as planned. Afterwards we swiftly packed our tools and components to travel home.

We had a great time at the ZARM in Bremen. Meeting all the other REXUS teams again was fantastic. A big thank you to everyone responsible for making this experience with its countless learning opportunities possible and stimulating conversations possible!

Check out some more pictures in the gallery in the Integration Week section!

Circuit Board Production

Our circuit boards are produced by us. If you are interested in the process then continue reading.
In the Gallery (Circuit Board Production), you can have a look at the pictures, which were made during the process.
After designing a circuit diagram, a model of the conductor tracks has to be printed on a transparency. It is used to exposure the board to the UV light. Thereafter it is developed in a caustic soda (NaOH) bath. The board is etched in a ferric chloride bath. You have to find exactly the right time, until the conductor tracks are perfectly visible. The bores are drilled before the rivets are affixed. Then we tin coat the board chemically. Afterwards the electrical components are soldered on.
Voila – the circuit board is finished 🙂

First Complete System Test

After a nice outdoor meeting, we performed our first complete system test yesterday. The results were convincing, although the mounting was not perfect. The control algorithm worked fine and the system reacted correctly.

Every time we spun it up, the algorithm detected the data from the gyros and triggered the valves. So the compressed air (we have a compressor to test the system with compressed air, which is cheaper) flowed through the nozzles and, because of the principle of actio-reactio, the whole system slowed down.

Integration Progress Review

Today we had our IPR, the Integration Progress Review. Experts from ZARM visited our team at our university to ensure that the progress of our system is going well.

After a short presentation held by us, we had an engaging discussion in a relaxed setting, where we received great suggestions and tips. Concluding the review an RXSM communication test was performed.
To sum up, the day was a success and we received a pass for the IPR.

Visiting one of our Sponsors

This week we visited “Peter Wahl GmbH & Co. KG”, one of our first sponsors.

They manufacture some of our components especially for us from our CAD-files, like the nozzle holders pictured in the gallery below.

Furthermore, we got a really interesting and thorough tour through the different facilities, got to see a lot of manufacturing, tool making and the like. Fascinating to see (and hear!) all these big machines, which usually make small parts that will be assembled to bigger parts and shipped off to e.g. the automotive industry. Normally you don’t get to see the assembly process of products from the start from really small and independent parts. Now we know where the process starts and get to appreciate the little parts, subcontractors and suppliers more for their work and help with complex products like e.g. cars.

If you would like to know more about “Peter WAHL Metall- & Kunststofftechnik” visit

Critical Design Review

3.1 After CDR
On Monday, 20th of June, four of us travelled to Oberpfaffenhofen, which is located near Munich, for our CDR. On the way down we visited the Flugwerft Schleißheim, an aerospace exhibition with lots and lots of interesting planes from the history of flying, including parts of the Europa rocket.
When we arrived at the hotel, we met the other teams and had a lovely evening at the Wörthsee lake.

The next day we went to the DLR site at Oberpfaffenhofen, which is one of Germany’s largest research centers, to attend to several interesting lectures and visit the GSOC (German Space Operations Center). Furthermore, the following “Ask your Expert”-Session was really helpful and we got some good advice. Finally, in the evening we had a common dinner with all teams and experts at the lake.

On Wednesday morning our fifth team member arrived, so we were complete to practice and present our experiment to the Review Board. The presentation went without a hitch and all in all went pretty well. In the discussion afterwards the SED (Student Experiment Document) was perused and the experts gave us some helpful recommendations and tips. Now it’s time again to wait for the CDR report before we will improve our SED with the insights of the experts.

After the CDR, in the late afternoon, four of us traveled back home to Würzburg. Tobias Wahl stayed two days longer to participate in a soldering course to further his skills and learn space-proven soldering.

We had a great time at the DLR and meeting all the teams again was really nice – lots of interesting conversations, topics, sightseeing and much, much more. We thank all people responsible for these experiences!

In the gallery, under Critical Design Review, you can see more pictures!