ReFEx

The Reusability Flight Experiment (ReFEx) is being developed by DLR to provide flight and design data from, and operational experience with, winged first-stage reusable launch vehicles. As such, the ReFEx will act as a small technology demonstrator and is scheduled for launch in 2025.

The experiment will be launched on a VSB-30 sounding rocket, reaching altitudes and velocities similar to a first stage separation. A return flight will then be attempted on a trajectory comparable to a returning winged first stage of reusable space transport systems, with a transition from hypersonic to subsonic flight.

ReFEx has a length of 2.7 metres, a wingspan of approximately 1.1 metres and a mass of approximately 450 kilograms. Outside the atmosphere, it is controlled by a cold gas reaction system and switches to aerodynamic control (canard and rudder) when atmospheric effects come into play. The highest Mach number reached during the re-entry manoeuvre is approximately Mach 5. Apart from the ability to fly on an optimised trajectory (autonomously controlled) to reduce thermal and mechanical stress, ReFEx will demonstrate its steering capability by flying a turn of at least 30°.

Key technologies demonstrated in this carrier include: aerodynamic design capable of stable flight through various speed regimes; guidance, navigation and control (GNC) capable of generating an optimised trajectory on board; seamless transition between extra- and intra-atmospheric flight controls; and in-flight monitoring of carrier status using advanced sensors such as fibre optic sensors (FOS) and flush air data system.

Other DLR institutes involved:

  • Institute of Aerodynamics and Flow Technology (AS)
  • Institute of Structures and Design (BT)
  • Institute of Flight Systems (FT)
  • Institute of Space Operations and Astronaut Training (RB)
  • Institute of System Dynamics and Control (SR)
  • Institute for Software Technology (SC)

References:

Contact

Dr. Tra-Mi Ho

German Aerospace Center (DLR)
Institute of Space Systems