Future Launchers Preparatory Programme

The Future Launchers Preparatory Programme (FLPP) is a technology development and maturation programme of the European Space Agency (ESA). It develops technologies for the application in future European launch vehicles (launchers) and in upgrades to existing launch vehicles. By this it helps to reduce time, risk and cost of launcher development programmes.
Started in 2004, the programmes initial objective was to develop technologies for the Next Generation Launcher (NGL) to follow Ariane 5. With the inception of the Ariane 6 project, the focus of FLPP was shifted to a general development of new technologies for European launchers.
FLPP develops and matures technologies that are deemed promising for future application but currently do not have a sufficiently high technology readiness level (TRL) to allow a clear assessment of their performance and associated risk. Those technologies typically have an initial TRL of 3 or lower. The objective is to raise the TRL up to about 6, thus creating solutions which are proven under relevant conditions and can be integrated into development programmes with reduced cost and limited risk.

The main objectives of FLPP are:

FLPP addresses the problem that in many cases, promising new technologies for future launcher applications possess a low TRL. At this stage, an implementation of such a technology into a development programme poses a significant risk. If it turns out, that the technology does not perform as expected in the later stages of the development or the concept using that technology is not feasible, a redesign of the complete system often has severe impacts on time, quality and cost.
FLPP addresses this issue via a system driven approach. Based on system studies for future launch systems or upgrades of current systems, promising technologies, which will provide benefits in line with the objectives of FLPP and have a low TRL (typically 2-3), are selected. These technologies are then developed to reach a TRL high enough (at least 5, typically 6) to allow their implementation into current or future development programmes with largely reduced risks. As technology maturation has already been performed in FLPP, the necessary time span to develop a new launcher is also reduced significantly.
The approach to mature a technology in a demonstrator based on system studies largely reduces the impact of worse than anticipated performance (e.g. in weight, efficiency, complexity) compared to a launcher development, were often a large part of the launcher design is affected by a change in the characteristics of a subsystem. After this "high risk" maturation phase the technology can then be transferred to a launcher development. A major change in the anticipated characteristics of a technology during the course of a development is much less likely when already starting with a high TRL (i.e. TRL 6) as compared to a technology of low readiness.

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