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.

Compass Rocket Paper now Available

In June, HyEnD had the honor to present a paper at the 2nd International Conference on Flight Vehicles, Aerothermodynamics and Re-entry Missions & Engineering (FAR 2022) in Heilbronn. The paper discusses the overall design and key technologies of our demonstrator rocket Compass. Insights in the design of the oxidizer tank, hybrid engine, pyrotechnical valves, recovery system and avionics are given. The paper is now available on ResearchGate.

HyLIGHT Engine Tested at Elevated Thrust Levels

Great news from the propulsion team. After the engine was tested successfully for a total impulse of 267 kNs in March at the 10kN thrust level, HyEnD encountered problems regarding combustion instability and high frequency oscillations at elevated thrust levels. 
As the rocket is operated in blow-down mode, the thrust continuously decreases during operation. Elevated initial thrust levels are necessary in order to ensure a sufficient initial acceleration when the rocket still contains its maximum propellant load.
After multiple short duration test firings in June and July, the design of the engine was optimized and now allows for stable, smooth, and efficient operation at thrust levels of up to 15kN. At 40 bar chamber pressure, a specific impulse of more than 230s was achieved. In the upcoming weeks, the entire propulsion system will go through final testing as the launch is getting closer and closer.

Flight version of drogue parachute tested

Great news from our supersonic drogue parachute! After evaluating the first test of our supersonic ribbon parachute, we not only improved the shape and design, but also the manufacturing and testing process. Three months later, we were finally able to test the flight version of the self-sewn parachute at Würth Airport in Schwäbisch Hall. We are now looking forward to testing the entire sequence of the recovery system.bWe would like to take this opportunity to thank Adolf Würth Airport GmbH for the use of the runway and the AMANN Group for providing the sewing yarns.

N2ORTH Oxidizer Tank Successfully Tested

Last week, we successfully tested the oxidizer tank of the N2ORTH rocket for the first time. The tank is a type V pressure vessel, which features a thin fluoropolymer surface coating on the inside to ensure nitrous oxide compatibility. The empty mass of the tank is only 16.8 Kg with a volume of 160 l and a nominal operating pressure of 75 bar. We are very satisfied with the result and are excited to see the behavior in the blow-down test.

HyLIGHT-2 Engine Tested for 25s

HyEnD is proud to announce that it has tested its HyLIGHT-2 Engine in near-flight configuration for its full intended operation time of 25 seconds. The test was conducted at the test bench M11 of the German Aerospace Center in Lampoldshausen and marks a big milestone for the development of the N2ORTH rocket.

The tested configuration has a dry mass of 13.5 kg and was loaded with 20 kg HTPB-based fuel. In addition, 2 kg of HDPE are located in the post combustion chamber in order to function as a film cooling ablator for the nozzle section. The multi-element swirl injector and graphite mixer in the post combustion chamber ensured a high reaction and overall engine efficiency, resulting in a specific impulse at sea level of 224 seconds. Operating at 30 bar chamber pressure and an oxidizer to fuel ratio of 6.07, an overall impulse of 267064 Ns was achieved.

The next test with minor optimizations of the design is scheduled for end of March. This test will be the final static test and will qualify the engine design. For April and May, integrated tests in blow-down configuration together with the rockets oxidizer tank, fluid system and ground support equipment are planned.

Take a look at the video of the test:

Drogue Parachute Tests

On Saturday, our self-developed and self-sewn ribbon parachute was tested for the first time. The parachute is designed for an operation point with low air density and high descent rates. Its main task is to slow down the fall of the rocket from supersonic to a sufficiently low speed to ensure a safe release of the main parachute. For this first test, we have built a small version of our drogue chute to familiarize ourselves with the manufacturing and testing procedures. After evaluating the test, we will design and build the bigger version for our rocket N2ORTH.

First HyLIGHT-2 Test with CFRP Casing

HyEnD is proud to announce that the first 15 s test firing of its lightweight engine HyLIGHT-2 with CFRP-casing was a success! In the upcoming weeks, the operation time will be increased to 25s. The test was conducted at the test bench M11 of the DLR Institute of Space Propulsion. Thanks to all who made this achievement possible!

YouTuber Senkrechtstarter zu Besuch

Please note that the video is only available in German.

Im Juli des vergangenen Jahres hat uns Mo vom YouTube-Kanal Senkrechtstarter besucht. Wir haben uns sehr gefreut einige Einblicke in die Arbeiten im Rahmen des aktuellen DLR STERN Projekts geben zu können. Unter anderem zeigen wir verschiedene Komponenten der Compass-Rakete und mischen mit Mo den Brennstoff für unsere Hybridtriebwerke an. Das Video ist nun auf dem Kanal Senkrechtstarter verfügbar – danke für deinen Besuch, Mo! 

First results of HyLIGHT Test Campaign

On 9th September 2021, HyEnD has successfully tested its HyLIGHT 10kN rocket engine for the first time. In contrast to the planned flight version of the HyLIGHT engine, the prototype engine tested features an aluminum casing. This allows a modular engine design and a reuse of insulation components in multiple test configurations. The first test was conducted with an impingement injector and film cooling ablator in the post combustion chamber. The burn time of the engine was restricted to five seconds, as the goal of the test was to prove that all required systems are working correctly and reliably.

The current test campaign will assess the effectiveness of film cooling and the influence of various design changes to the combustion efficiency. The regression rate will be evaluated and optimized as well. Since September, various prototypes of the engine have reached a culminated operation time of more than 37 seconds. In the following weeks and months, the design of the fuel grain, injector and insulation components will be finalized, and the burn time increased to up to 25 seconds. First tests with an engine with CFRP casing are planned for early 2022.

Update from January 2022: We now have conducted a total number of 7 hot fire tests within the HyLIGHT-1 test campaign. Some impressions from the tests are summarized in the following video: