Status of projects for the future European launch vehicle

Current design concepts for the Ariane-5 launcher, to replace the Ar-4 in the mid-1990's and provide the ability to place 15 tons in LEO (corresponding to 4-5 tons in GEO) are reviewed and illustrated with drawings. The large cryogenic engine (LCE), currently defined as having 1.05-MN nominal thrust and more than 445-sec specific impulse in a second-stage version, is employed in all current concepts. The CNES concepts presently favor a solid-propellant first stage, while the ESA concepts aim for a recoverable or semirecoverable LCE-based first stage; both use LCE second stages and represent departures from the current Ar-1-4 series. The DFVLR concepts call for a stepwise development from the Ar-4G (boosted Ar-4 first stage plus 75 and 10-ton LCE second and third stage) to a final 'Ar-6' configuration with a 200-ton first stage; both first and second stages of the Ar-6 are to be recoverable. The ESA decisions on the LCE and overall designs are due in June, 1984 and in 1986.