News

Launch Campaign Announcement

We are proud to announce the date of our launch campaign! From 11th to 25th April this year, 16 HyEnD team members will visit the European Space and Sounding Rocket Range (Esrange) close to Kiruna, Sweden. And we plan to not bring one – but two N2ORTH rockets with us!

The launch of the first N2ORTH rocket is planned with 80° of elevation and with limited propellant mass, in order to ensure a safe downrange and landing area. If all goes according to plan, N2ORTH will reach an altitude of more than 50 km at its first flight and we will get the permission to increase the elevation for the second rocket launch. The launch of the second N2ORTH rocket is currently planned with a higher elevation and increased propellant mass.

As of now, a space shot is not off the table but will also depend on the results of the first launch and weather conditions. We are looking forward to share more details about the launch campaign in the upcoming weeks.

Successful Validation of Thermal Protection System

In order to complete final research concerning thermal loads, HyEnD conducted thermal tests on December 20th, 2022. The thermal tests were a crucial milestone and provided us with valuable insights into the expected in-flight behavior of N2ORTH.

During a test campaign, we tested the nose cone, fins, and 3-ring system of the parachute. The tests were conducted under realistic conditions corresponding to a speed of Mach 2.5, equivalent to the predicted max Q conditions. Thus, with this test, the maximum aerothermal load that we expect during our flight could be tested.

First the fins were tested. Due to the surface standing perpendicular to the flow direction, high heat loads are expected here. During the test, the leading edge of the fins was able to withstand the thermal load expected at max Q for over a minute. This is significantly longer than expected in flight, so we are confident in our design.

Subsequently, the nose cone was tested. We tested not only the structure of the nose cone, but also potential camera recesses. We confirmed that the thermal loads can be safely withstand even at the location of a recess. With this test, we validated for a second time that our thermal protection at the nose cone can withstand the loads with a high degree of reliability.

By testing the 3-ring-system of the recovery, it should be verified whether a premature triggering of the pyro-cutters can occur due to the heat load. It should be mentioned that our recovery system will never be exposed to such thermal stresses during our flight compared to max Q. In order to perform a maximum estimation here as well, the system was also tested at max Q conditions. The thermal tests showed that the cutters are not triggered prematurely by thermal stresses. In a subsequent test in which the cutters were intentionally triggered, it was demonstrated once again that the 3-ring system reliably releases the connection when the cutters are ignited.

Many thanks to the DLR Institute of Space Propulsion in Lampoldshausen. Due to their support at the M11 test bench and access to the air heater for supersonic tests, we were able to successfully carry out our tests.

Final Propulsion System & Loading Procedure Test of N₂ORTH

HyEnD has successfully conducted its final system test on Thursday, 8th December! The test included the oxidizer loading procedure using the Ground Support Equipment as well as a hot fire with the hybrid engine and rocket’s fluid system components.

During the oxidizer loading procedure, temperatures and pressures were measured across multiple parts of the Ground Support Equipment and 160 L oxidizer tank. We are happy to report that the test showed a high level of precision during the loading procedure, as we were able to precisely set the amount of oxidizer as well as temperature and pressure conditions in the tank.

The hot fire of the propulsion system showed stable and efficient combustion throughout the operation time. With a peak thrust of more than 15 kN and a total impulse of 255 kNs at sea level, we are confident that the propulsion system is capable of pushing N2ORTH to the frontier of space. The in-flight impulse of this configuration will be even higher since effects like flow separation will occur later in the operation time due to lower ambient pressure at higher altitudes. Moreover, the test showed good accordance to the simulation carried out in advance. This is especially important to ensure a safe flight trajectory of the rocket.

A video of the test can be found on YouTube:

As this was our final hot fire within the scope of the STERN 2 project, we would like to thank the DLR Institute of Space Propulsion for their fantastic support during the last years. Since September 2020, more than 60 hot fires were conducted, and we learned a lot! We are now fully focused on the final production and assembly steps and are looking forward to our launch campaign in April 2023.

Recovery System Test successful

Flying up to 16,000 feet and dropping 79 kg from an aircraft: Under these conditions, we were able to perform the first system test of the entire recovery system of our sounding rocket N2ORTH. By evaluating the drop sequence, we could determine whether all components of the two-stage system work nominally in interaction with one another. At the same time, we wanted to investigate the canopy behavior during deployment in subsonic conditions as well as the integrity of all structural components.

Apart from minor design flaws in structural components, the test was completed successfully. Both parachutes withstood the occurring loads and showed a stable descent. The load switch from the drogue the main parachute worked out properly with a nominal main parachute deployment at about 1,000 m above ground. After descending 300 s, the drop test demonstrator landed safely in the designated landing zone of the Heuberg military training area.

We would like to take this opportunity to thank all our partners who supported us in the successful realization of this project during the last month. Big thanks to the companies like “LIROS GmbH” (ropes), “Amann & Söhne GmbH & Co. KG” (yarns), “Güth & Wolf GmbH” (aramid bands/harness), “EDELRID GmbH & Co. KG” (shock absorber), “Heathcoat Fabrics Limited” (drogue parachute aramid fabric) and “EVOTEC” (main parachute) for providing materials/components together with technical support.

Furthermore, a special thanks goes to the German Armed Forces and “Skydive Saulgau GmbH“ for the safe conduction of our test.

N₂ORTH Rocket Unveiled for the First Time

Our new rocket N₂ORTH was unveiled for the first time at an event at the Materialpruefungsanstalt (MPA) Stuttgart on Wednesday, 26th October.
In the days before, three years hard work of more than 60 students came together for the first time. The project is funded by the STERN programme of the German Aerospace Center. Thanks to its dry mass of less than 70 kg, up to 145 kg of propellant mass and the efficient propulsion system, N2ORTH is HyEnD’s most powerful rocket. We are proud to announce that N2ORTH is also technologically capable of reaching the frontier of space, the Kármán line. However, the targeted altitude is still subject to change and will be chosen in accordance to our trajectory simulations, safety regulations at Esrange and weather conditions. The launch of the rocket is currently planned for April 2023.

The unveil of the rocket took place in the presence of representatives of the University of Stuttgart, the German Aerospace Center and partners from industry. We especially want to thank the Coordinator for Aerospace of the German Feder Government, Dr. Anna Christmann, for her visit.

Read more about the event here:

https://www.uni-stuttgart.de/en/university/news/all/hyend-rakete/

The German press also covered the event:

https://www.stuttgarter-zeitung.de/inhalt.uni-stuttgart-studenten-bauen-ihre-eigene-rakete.c0e65696-9887-42a2-a21c-8cf17964c819.html

https://www.swr.de/swraktuell/baden-wuerttemberg/stuttgart/rakete-von-studierenden-in-stuttgart-vorgestellt-100.html

Photos: HyEnD, MPA Stuttgart

Interested to join? Meet us!

English version below

Wir, die Hochschulgruppe Hybrid Engine Development – kurz HyEnD – sucht neue Mitglieder. Im Jahr 2016 haben wir mit unserer Rakete HEROS den Höhenrekord für studentische Hybridraketen (32 km) aufgestellt. In wenigen Monaten möchten wir diesen Rekord mit unserer Rakete N2ORTH brechen. Parallel dazu beginnt JETZT die Vorbereitung für das nächste Projekt – und wir brauchen dich!

Ein paar Infos vorab:

•  Mitmachen können Studierende der Universität Stuttgart aus ALLEN Studiengängen
•  Ein Einstieg im ersten Semester ist ohne Problem möglich und oft sinnvoll.
•  Vorteile: Du sammelst Erfahrung in einem technisch herausforderndem Projekt, kannst dein theoretisches Wissen aus dem Studium anwenden und bekommst erste Kontakte zu Industrie und Wirtschaft
• Zeitaufwand: 2 Meetings pro Woche (Gesamt + Subsystem) + Zeit zur Erledigung deiner Aufgaben

Du hast Interesse?

Dann komm zu unserem Treffen für alle Interessierten und nimm Kontakt mit uns auf. Beim dem Event gibt es weitere Infos und du hast die Chance unsere Rakete N2ORTH aus nächster Nähe kennenzulernen.

We are looking for new members! In 2016, we set the altitude record for student hybrid rockets (32 km) with our rocket HEROS. In a few months we plan to break this record with our rocket N2ORTH. In parallel, the preparation for the next project starts NOW – and we need your help!

Please note:

• You have to be a student at the University of Stuttgart. All study courses from all semesters are welcome!
• Usually, every team member participates in two meetings per week (overall team meeting and subsystem meeting). You will need additional time to work on your tasks.
• Meetings are usually in German.

You are interested?

Come to our meeting and contact us. At the event you will get more information and have the chance to get to know our rocket N2ORTH up close.

N₂ORTH – Aiming for new heights

We are happy to share a small teaser for the upcoming reveal and launch of our rocket N2ORTH! In the last three years, the team worked hard to make this rocket a reality. The rocket now is almost ready to launch, with only a few last tests and the assembly ongoing. The launch from Esrange is planned for the first half of 2023. As for the target altitude, we plan to break our own record for student-built hybrids (32.3 km) but N2ORTH is a lot more capable. The target altitude is still subject to change and will be chosen in accordance with our trajectory simulations, safety regulations at Esrange and weather conditions. Stay tuned for more details!

N₂ORTH Propulsion System Test in Blow-Down Operation

The N₂ORTH propulsion system was successfully qualified in a hot fire test for a propellant throughput of more than 100 kg on August 25th. This marks an important milestone for the project, as HyEnD now has a flight-worthy propulsion system for the launch.

The fluid system of the ground support system (GSE) was used in order to fill the oxidizer tank with nitrous oxide and helium. The GSE includes two intermediate tanks for storage of the required amount of nitrous oxide for the filling process as well as a remote filling arm with a quick disconnect coupling.

The test setup includes the valves of the rocket as well as additional valves that are controlled using the test bench. An overview of the setup can be found below:

During the test, the rocket’s oxidizer tank was operated in a blow-down configuration together with the fluid system and engine of the rocket. The hot fire of the engine included the main operation phase of the engine and also the gas blow down after the depletion of liquid oxidizer, resulting in an overall hot fire duration of more than 50s.

In the upcoming weeks, the team will prepare another test with increased propellant mass in order to unlock the full potential of N2ORTH.

Recovery Tests at IFT

As the launch of N2ORTH is getting closer, last validation tests of the recovery system are performed before final assembly. In mid-July a drop test was performed to verify the mechanical integrity of several recovery components.
The experimental setup is based on a drop test bench where a drop weight can be lifted up to 7m. At the end of the fall length, an impact plate transmits the energy of the falling weight into the connected recovery components. By applying a dynamic load equal to the opening shocks during main chute deployment, the recovery mount to the rocket’s hull structure was tested. All components withstood the required design loads over several load cycles without substantial damage.
Furthermore, the modification of the shock absorber was determined by these tests.
We want to thank the Institute of Mechanical Handling and Logistics for the technical support with the drop test bench.

N₂ORTH Integration and Alignment Process

HyEnD has started the integration process of its N2ORTH rocket for the launch in Esrange later this year. One of the most crucial aspects of the rocket assembly is to ensure precise alignment of the components. Every slight deviation can have an influence on the flight trajectory and has to be considered in the mission analysis.

We achieve alignment by using a laser beam and photogrammetric measurements: First, the laser beam is aimed over a notch in order to align it with the tank axis, which was determined in a previous process. For the next step, the tube connector is inserted partially into a segment of rocket structure. Two targets are placed onto the structure segment aligned with its axis. The targets consist of grids perpendicular to said axis. After that, the structure segment can be aligned to the tank axis. Alignment is achieved when the laser beam intersects the two grids at the same point. Next, the tube connector is connected to the tank with a small amount of epoxy.

In order to evaluate the alignment, photogrammetry is used. This method generates point clouds to which cylinders can be fitted using CAD software. The offset and angle between the different parts then can be analyzed. Different plausibility checks are performed in order to ensure that the obtained measurements are viable.