Early British solid propellants
The first solid propellants were homogeneous propellants obtained by press extrusion (EDB, Extruded Double Bases) or by casting (CDB, Cast Double Bases). Plastic propellants were produced since 1938, prior to the opening of hostilities. After the war, work was directed towards producing plastic composite solid propellants employing ammonium perchlorate and picrate and polyisobutylene binder.
17 inch British solid motors
Early British Army SAMs (Red Shoes, later Thunderbirds) were powered by solid propellant sustainers, 17 inches (43.2 cm) in diameter. After some liquid propelled prototypes, the Red Shoes vehicles were successively propelled by Ratcatcher, Smoky Joe, Elkhound, Wolfhound and Albatross. The motor intended for the upper atmosphere sounding rocket (which later become Skylark) was created starting from the experience gained with these series. Raven, obtained by welding three Smoky Joe tubes together, contained 840 kg of propellant (the later versions reached 1020 kg). Cuckoo, with 180 kg of propellant, was half less long than Smoky Joe whereas Goldfinch, with approximately 310 kg, had the same size. The last of the series, Rook, designed for fast burning, was as long as Raven and carried 880 kg of propellant.
Early French solid propellants
The first solid propellants were homogeneous propellants of which the blocks were pressed (SD) or cast (Epictète) charges. In early Sixties, the composite propellants allowed the construction of wider blocks with higher specific impulse. Three categories of composite propellants appeared successively in France: Plastorgols with polyvinyl chloride binder, Isorgols with polyurethane binder and Butargols with polybutadiene binder. Each of them existed in two versions: without aluminium additive (Plastolite, Isolite and Butalite) and with aluminium additive (Plastolane, Isolane and Butalane).
560 mm French solid motors
Solid propellant blocks, 560 mm in diameter, equipped first of all, in SEPR 732 version, the boosters of experimental SAMs such Matra R422B or SE 4400, then VE9 rocket. These engines carried 470 kg of propellant, giving a total impulse of approximately 940 kNs in 4.7 seconds. With 985 kg of propellant, the SEPR 737 motor of VE10 rocket burned during 15 seconds. Stromboli intended for Dragon, Dauphin and Eridan sounding rockets comprised 685 kg of propellant and delivered 1485 kNs in 16 second. Largest of the series was the SEPR 739 which, with 1245 kg of propellant, gave 2860 kNs in 20 seconds. It equipped the first stage of Berenice, Tacite, Titus and Tibere rockets. SEPR 740, intended for the second stage of Berenice and Titus, used a 738 kg charge and delivered 1650 kNs in 18 seconds.
IRIS (Italian Research Interim Stage)
This solid-motor was developed by Alenia as a perigee stage for launching 600 to 950 kg payloads from the Space shuttle. The IRIS is composed primarily of two elements: the reusable launch platform (ESA) including a spinning table (45-100 rpm) and the consumable solid-rocket motor (SRM). This BPD motor is 1.94 m long (with the nozzle), 1.30 m in diameter, and weighs 1721 kg including 1574 kg of propellant (HTPB) in nominal version or 1328 kg in reduced version (-25% of propellant). It provides a total impulse of 4490 kNs in 79 sec in the first case, 3370 kNs in 63 sec in the second. The Challenger disaster reduced the IRIS career to only one launching. It had also been proposed like upper stage for the Vega launcher (1st version).
This solid-motor was developed by SEP/BPD/MAN as an apogee stage for geostationary satellites. It was also proposed as an upper stage for the Skylark 17 rocket. It is a 1.52 m length engine, 77 cm in diameter, weighing 530 kg including 490 kg of propellant, and capable of providing approximately 1412 kNs in 44 seconds.