RUAG Space (CSA CSM) has successfully developed and tested a new, low shock jettison system funded by the Future Launchers Preparatory Program (FLPP) of the European Space Agency (ESA). The program develops technologies for future European launch vehicles and upgrades of existing launch vehicles. This system enables a quieter and smoother journey to space for satellites or other payloads.

RUAG Space in Emmen, Switzerland, has produced the required payload fairings for the European launchers Ariane and VEGA since the 1970s, and, as part of the FLPP, has developed this new separation and jettison system for payload fairings. Payload fairings are nose cones used to protect spacecraft and technology from impact, dynamic pressure and heat during take off and flight. Fairings are jettisoned outside Earth’s atmosphere.

More comfort thanks to low shock load
The payload fairing protects the satellite from aerodynamic and thermal loads during flight. After passing through dense atmospheric layers, as soon as the satellite is no longer at risk, the payload fairing is separated from the launch vehicle. As a rule, two pyrotechnic mechanisms are fired to open hinges, allowing the half-shells to separate safely from the payload.

“Pyrotechnics is a proven technology, but may generate significant shock during activation and may result in excitation that needs to be considered in the design of the launcher and payload hardware,” says Alberto Sánchez Cebrian, RUAG project manager.

Lower development costs and simpler test conditions
The RUAG separation and jettison system has a modular design and reduces development costs, as parts can be improved or replaced without affecting the entire system. Testing is easier and the mechanism does not require synchronization. The tests were carried out at the Emmen site on a 2.6-meter long Vega payload fairing. The new system is scalable and could also be used in the European launch vehicle, Ariane.

In addition to the successful separation test, a significant noise reduction was achieved. An integrated sound reducing perforated insulation layer within the sandwich panels of the payload fairing enables noise reduction without increasing mass and volume. In certain frequency bands this system could replace acoustic absorber mats currently used in payload fairings. Testing and evaluation of this new system will continue in the next phase of the project.