Nebula Public Library

Propulsion passivation is most of the time feasible for running missions, using thrusters and existing AOCS modes, whatever the number of tanks and for both monopropellant and bipropellant systems.
For monopropellant systems the propulsion passivation may be:
-Partial for tank(s) with membrane. All the hydrazine under the membrane may be depleted but the pressurant gas above the membrane cannot be depleted. The final tank pressure is close to typically 5 bars at the end of mission.

Generally speaking DIAMS has been an opportunity to secure the feasibility of the IOD in technical, programmatic and financial terms. More specifically DIAMS has allowed to define the end-to-end mission concept for this IOD, covering the design of various associated segments : Space Segment (Payload, Platform), and Ground Segment. Both interest and programmatic aspects have also been consolidated.

- On the technical plane :
Both the requirements and the design of the system have been refined to validate the IOD concept :

The purpose of this GSP activity was to assess the capabilities of non-intrusive diagnostic techniques for internal measurements in ablative materials during PWT tests. This initial steps were to identify the measurements to be performed in relation with high-speed Earth re-entry, and to identify the accessible parameters as well as related diagnostics techniques. For this objective an extensive review of the possible measurement methods, with a focus on non-intrusive diagnostics, has been undertaken.