The Doongara Balloon Cut-Down Device is a small self-contained thermal line cutter that utilizes redundant burn-wires to sever synthetic line commonly used on high-altitude weather balloon flights. The device has an on-board barometric pressure sensor and timer to determine when to sever the line based on user-programmable settings. Doongara version 3.1 and later can be connected to a line-of-sight radio or satellite modem for real-time command of the line cutter.
Features of the Doongara Balloon Cut-Down Device
A variety of Advanced Latex Balloon Flights are made possible by using Doongara with simple latex weather balloons. For example, Doongara makes controlled tandem ballooning possible. With tandem ballooning you now have control over the duration of the ascent, float, and descent stages of the flight. This results in more useful time at altitude for your payload.
- User-programmable line cutter triggered by:
- Atmospheric pressure level
- Elapsed time
- Balloon burst detection
- External payload signal
- Records pressure, temperature, and termination
- Installs quickly between payload and balloon
- Reusable and non-pyrotechnic
Has been used on NASA scientific balloon flights
See the flight profile images above for graphical representations of how these triggers can be used. Any combination of the triggers is permitted. When multiple triggers are enabled, the first trigger condition to be satisfied cuts the line.
- Mission Elapsed Time Trigger—severs the line after a user-specified amount of time elapses.
- Minimum Atmospheric Pressure Trigger—severs the line once a user-specified atmospheric pressure level is achieved during balloon ascent.
- Rapid Descent Trigger—severs the line when a rapid and sustained pressure increase is sensed (like after balloon burst).
- External Signal Trigger—this is an optional feature that severs the line when a signal from a line-of-sight radio, satellite modem, or your payload is received.