TDS-80

Tycho Deep Space 80, is a scaled down version of Tycho Deep Space II. It is aerodynamically equivalent to TDSII and has served as a small scale test vehicle. It is made of aluminum and weighs 80 kg, hence the name.

Early development stage visualization of TDS-80. Image: Thomas Pedersen.

Early development stage visualization of TDS-80. Image: Thomas Pedersen.

Bringing a space capsule safely down from a 100 km suborbital trajectory is a very difficult task. TDS-80 is a test vehicle for experimenting with several key features of a high altitude descent. First and foremost the vehicle must be aerodynamically stable during descent to prevent it from tumbling. On TDS-80 this is achieved by deploying a ballute shortly after apogee. The ballute is attached to the top of TDS-80 and will keep TDS-80 in a heat shield first attitude during descent. At a lower altitude the ballute is jettisoned and a parachute is deployed to ensure a safe landing at sea. In the following several key components of TDS-80 is described.

TDS-80 subsystem scetch. Image: Kristian von Bengtson.

TDS-80 subsystem scetch. Image: Kristian von Bengtson.

Top lid
This lid on the TDS80-capsule is not only the actual nose cone of the entire rocket but also the cap of the bay containing the recovery systems for the capsule. The top lid is made from plain carbon steel but has a 10-50 mm layer of cork for heat protection of the systems its holding. (ballute, drogue, flotation device). So far, we are likely to use an airbag-charge to provide and instant overpressure for top lid jettison.

Ballute
The space capsule ballute is a balloon/parachute combo system which is deployed at apogge. This drag-device can withstand super sonic speeds while providing just enough drag in the thin part of the atmosphere to ensure a correct orientation of the capsule during re-entry. The ballute will be released after atmospheric re-entry using a standard 3-ring system pulling the drogue for deployment which is used during splashdown.

Flotation device
The capsule has a mass of 80 kg and does not float. A dedicated flotation device must be installed and will be released for use during splashdown to ensure safe recovery of the capsule.

Parachute bay
The containing under the top lid holding ballute, drogue and flotation-device.

Camera x 2
The capsule will be installed with two wide angle cameras pointing towards the horizon. The feed will be recorded on board and transmitted to ground control for live-viewing in mission control and Youtube.

Exploded view of TDS-80. Image: Kristian von Bengtson.

Exploded view of TDS-80. Image: Kristian von Bengtson.

GPS Antenna
A number of GPS-antenna systems (without altitude and speed limitation) will be added to provide live data for mission control on general FIDO-positioning.

Antenna send/receive
The capsule will transmit all on board computer data and video to mission control for live mission analysis and for general record keeping, if the capsule is lost later during the mission.

Avionics
There will be four main avionics boxes installed in the capsule for all data handling, communication, navigation and video.

External interface
The main side of the capsule provides access to the main interface of the capsule. This interface is used for data-handling, charging and activation of systems prior to launch.

Batteries
The capsule will have a number of NiMH, 13.2 V battery-packages installed in the bottom providing power for all on-board systems during the entire mission phase.

Kristian von Bengtson Welding on the internal structure of TDS-80.

Kristian von Bengtson Welding on the internal structure of TDS-80. Photo: Thomas Pedersen.

Currently there is no launch date for the TDS-80 mission but it will most likely be launched in 2015 from the Baltic Sea.