Amateur space projects
There are many amateur space projects out there. Some are low altitude, while others are nearly professional. Amateur space projects are defined as a project that is not funded by a government and is not run by a company. All people participate in their free time and consider the work they do a hobby.
Parachutes of DARE and Copenhagen Suborbitals
Copenhagen Suborbitals
Copenhagen Suborbitals was founded in 2008 and has flown 6 rockets to date. The goal, to bring a person above the Karman line in a home build rocket. The last launch, in 2018 was the Nexo II rocket. The parachute system functioned almost as expected. At apogee the rocket separated, the ballute deployed and slowed down the rocket. Finally, the main parachute deployed. The parachute was supposed to be reefed, however, this seemed to not go as planned.
A ballute parachute is capable of operating at very high Mach numbers, Furthermore, by using tricks to keep the inlets open or inserting an inflation system, one can deploy the parachute system. For Nexo II the ballute was deployed at 6.5km, however, the STIG-A rocket of Armadillo Aerospace deployed the ballute at high altitudes. The choice to go for a ballute could originate from the need to have a stable capsule during atmospheric entry. One does not want an astronaut to tumble during atmospheric entry. After the ballute flight phase three main parachutes, ringsail type, are deployed. A cluster is used to decrease the size of the individual parachutes, and introduce redundancy.
A subscale ringsail cluster in wind tunnels for testing
Stratos
Operator: DARE
Mission: Space shot
Flight: 2015, 2018 and 2021
Delft Aerospace Rocket Engineering, DARE, is a society in Delft with the goal of reaching space. To achieve this the Stratos flagship missions were founded with the first launch in 2009 reaching 12+ km. During the flight of Stratos II+ in 2015, it was seen that the parachute system did not work as anticipated. The two-stage parachute system consisting of a disk gap band drogue parachute and a cross main parachute was to retrieve the entire rocket. To deploy the parachutes, the rocket was split up into the nose cone and tank sections. Directly after separation, the drogue broke off and caused the tank to plummet back to Earth. The nose cone followed in a ballistic trajectory but entered a flat spin. The flat spin was caused by the nose cone being aerodynamically unstable due to the lack of fins. This allowed the nose cone to slow down to velocities where the main parachute was able to recover the nose cone leading to a successful mission, and partial success of the recovery system.
September 2016 saw the creation of the Stratos III mission, for this mission, a more reliable recovery system was required. This time to only recover the nose cone of the rocket to reduce the mass of the recovery system. The nose cone houses the sensors and storage, allowing the team to confirm the flight. This system consisting of an aramid Hemisflo drogue parachute and a cross main parachute was dubbed the "Large Envelope Advanced Parachute System". This system allowed for high flexibility in future missions in terms of mission parameters, and modifications to the system. The system relied on the nose cone to enter a flat spin and would only deploy the drogue parachute at low (4 km) altitudes. As the nose cone would be in a flat spin, the drogue parachute could entangle with the body. Therefore the drogue parachute was shot out using a Cold gas deployment system.
As Stratos III broke up in flight due to dynamic instability, the system was never tested in flight. However, Stratos IV will fly a new iteration of LEAPS. The two main modifications include a switch to a hot gas deployment device for the drogue parachute and a Disk Gap Band main parachute. This iteration of LEAPS will be tested in the Supersonic Parachute Experiment Aboard REXUS (SPEAR). This DARE mission is part of the 12th cycle of the REXUS/BEXUS program organised by SNSA, DLR, ESA, ZARM, and SSC.
In the summer of 2021, the Stratos IV launch was delayed due to problems with the filling arm. In 2022 it was announced that a re-flight of the rocket would not be attempted.
The drogue parachute used on Stratos III, Stratos IV and SPEAR.
Zephyr
Operator: ERFSEDS
Mission: Supersonic and high dynamic pressure testing of parachutes
Flight: 202x?
Status: delayed due to COVID-19
Zephyr is a supersonic parachute experiment by ERFSEDS. ERFSEDS or Embry-Riddle Future Space Explorers and Developers Society. It is an extracurricular club that offers many different projects focused around space, rockets, and engineering to anyone who is interested. We are the largest engineering club on campus and have been around since 1992.
The rocket, a boosted dart design, will lift of reaching Mach 1.5 where the test section and engine section will separate. The upper "stage" contains a set of avionics and a mortar. Right after separation, the upper stage will deploy the parachute. The parachute will be a 5-foot disk gap band design. The lower stage flies off to eventually deploy its own parachute and the upper stage deploys its experimental chute from the rear of the vehicle after a short time to make sure that the lower stage is clear. After the upper stage has reached apogee a second parachute is deployed. This parachute ensures a safe landing even when the experimental parachute fails.
Zephyr flight path
Daedalus 2
Operator: Julius Maximilian University of Würzburg
Mission: Controlled landing using auto-rotation
Flight: 2022
Status: planned
As part of the Rexus/Bexus program, Daedalus 2 is trying to perform a descent and landing using an auto-rotation system. Building on from Daedalus project that flew on REXUS 23 they will change the system and instead, on a fixed rotor Daedalus 2 will have a free rotating rotor. The goal of the project is to develop this rotor system as well as the control software to be able to land the system safely.
The vehicle will be inside the nosecone of the REXUS rocket. The Daedalus 2 consists of two-vehicle both similar to each other. The vehicle has a diameter of 85mm. When rotors are folded and the rotor has a diameter of 960mm when unfolded. It has a mass of 2.2 kg. These rotors have the aim to land the vehicle with a velocity of 10m/s. As part of the 13th cycle of the REXUS/BEXUS program, Daedalus 2 is still in development and was to fly in March of 2022. However, due to the current global political situation, the flight has been postponed to March 2023. [97]
Transpiration Cooling Experiment
Operator: Space team Aachen
Mission: Inflight technology demonstrator of transpiration cooling
Flight: 2024
Status: planned
Another REXUS/BEXUS mission is the TRACE or Transpiration Cooling Experiment of the Space team Aachen. The capsule will be stored in the nose cone of REXUS and will free fall down. During the down leg of the mission, a cooling gas will be pushed through a porous wall cooling the skin. This form of active thermal protection can reduce the mass of the overall system as it does not require a heat shield.
