I woke up to read this facebook post from HyEnD, who consist of students from the University of Stuttgart. The team’s rockets HEROS 2 and 3 are set to start their launch campaign come October 24th from Kiruna in Sweden and aim to achieve more than 20km of altitude.
From August, the stats of HEROS 2:
- Length: 7.5
- Diameter: 0.223 m
- Hybrid rocket engine (nitrous oxide and paraffin)
- Maximum takeoff weight: ~ 177 kg
- Thrust: 10,000 N
- Altitude: about 21.5 km
- Recovery System: Multi-stage parachute Salvage System
- Objective: European altitude record for student rocket
Of note is the two HEROS rockets, building two rockets side by side came up in an Arocket post a few years ago by John Carmack of Armadillo Aerospace (now EXOS Aerospace). John was talking about building suborbital rockets but the concept is the same. By building two side by side, batch production and labour intensive tasks become much more effective, and in trying to achieve these goals it is more than likely that you will lose a vehicle or two.
This altitude will no doubt have the team at DARE a little worried as they currently hold the European altitude record for amateur rocketry of 21.457 km with their Stratos II+ rocket, set last year. The team is working on Stratos III, so I imagine if the record is taken they will come back and reclaim it as their original goal for Stratos II+ was 50km, I’d bet they would be aiming to reach that again.
Video Caption: Test 16 of our 10000 N Hybrid Rocket Engine “HyRES”. This was done with the configuration and conditions during our launch in October 2015. As we expected from theory, the combustion is clearly unstable under these conditions and we modified these conditions for the next test 17, which shows excellently stable behavior.
HyEnD – Hybrid Engine Development: http://www.hybrid-engine-development.de/
From the teams Facebook page:
A further important step of our analyses and tests was, to get to the bottom of the launch failure last year. With test 16, as in the video below, we could show, that a too low nitrous oxide temperature at launch was responsible for instable combustion in the engine. This increase thermal and mechanical loads and lead to the failure of the engine.The configuration and conditions of test 16 represented the same as the launch last year. Compared to test 17 the differences in stability can be recognized easily.
The Aquasonic teams rocket, dubbed Aquasonic, a 5m long 200mm diameter hybrid rocket has been found after its April launch from Esrange in Sweden.
Unfortunately, the rocket was unable to be recovered at the time of launch but has since been found, a little worse for wear, though! The team hopes to extract what information they can from the rocket to get a detailed event of what actually happened.
The launch can be viewed below.
Video Caption: This is the first test of the upgraded version of the “Frigate” hybrid rocket engine, conducted on 2016-05-29. Using a star shaped fuel grain with a 3D-printed geometry, the engines thrust was increased by about 1000 N. During its burn time of 5 s, the engine smoothly burned over 1.3 kg of solid HTPB fuel.
The test confirmed the predicted engine characteristics and thereby validated our performance models.
We will soon test the engine again, to confirm our results.
Subscale Engine “Frigate”:
Propellant: HTPB + LOX
Thrust: 1550 N