InfraNut2 thanks for posting this ahead of me
I think Nammo has a really nice technology with this. They are going to supply a HTP Hot Gas Reaction Controll system for Ariane 6, if I'm not mistaken. They have developed a smaller hybrid engine that was used for the FP7 SPARTAN lander test program. The FWUM-1 that is being tested now will be used in Nucleus (1xUM-1). I think the nucleus will be a nice replacement for the imp. Orion and S30 rocket launches. Nammo is involved in both the Altair and SMILE Horizon2020 programs. More details about unitary engines can be found inside the SMILE project document.
Info from this document:
The Hydrogen Peroxide (87,5%) is decomposed by a cathalist, Steam of 670 deg. C and gaseous oxigen (? radicals/free atoms) get created by this. This 670 deg. C is hot enough to ignite HTPB (a special Nammo formulation) but it could also ignite paraffin, RP-1 or Ethanol. If I'm not mistaken another European company is developing HTP-Cathalist bi-liquid igniters for re-ignitable liquid engines.
Nammo has developed different cathalist pack sizes, small ones for the RCS thrusters, one for the test engine and the one for UM-1 can compose 10,8 kg/s.
The FWUM is a bit more capable then the HWUM. The diameter has increased from 12 to 14 inch (305mm => 356mm),
I think to match with the Hotel and REXUS payload systems.
The HWUM could burn at 30kN for 25s = 750kNs.
The FWUM should burn at 28kN for 35s = 980 kNs (@30kN = 1050kNs)
The dry mass will be less then 100kg; and in 35 seconds more then 60kg HTPB and ~380kg HTP will be consumed. by the UM-1 engine. The ISP is higher then 230s.
The UM-1 will be used in the Nucleus (1xUM-1; 1 MNs) and Aurora (4xUM-1; 4 MNs) stages.
Next to the UM-1 there are also plans to develop a UM-2 (higher Trust and longer burn time). That will be used in Borealis (7xUM-2) gives 450kN, 64s 30MNs. So UM-2 will burn at 64,3kN for 64s (about 4,2 MNs).
And an upper-stage Corona with a (High Performance Hybrid Motor) 5kN, 70s = 0,35 MNs engine.
I think the HPHM will be the most difficult because the different regression rate. UM-2 will need a larger cathalist pack.
If all this will be developed successfully I think the North Star rocket family will dominate the European sounding rocket launches. I expect that MoRaBa will replace the S30, S31, S40, S43 and S44 with North Star stages. Borealis can replace the S50 stage that is being developed for VLM-1. A 4xUM-2 will be a replacement for the S40.
If the HPHM does not work out, I think HTP (>87,5%) and ethanol is a really nice green hypergolic liquid upper-stage combination. (possibly also nice for an in orbit stage like AVUM and Fregat.)
Possibly there is also a need for a smaller Unitary engine then UM-1 (250kNs). But there is no harm on leaving this market open for Universities.