NW061 1/144 L-4S (Lambda-4S) First Japan Satellite Launch Vehicle


The L-4S rocket was the first rocket developed by Japan to launch a satellite into orbit. The launch vehicle was similiar to a very large sounding rocket. All four stages and both strap-on boosters were powered by simple solid rocket motors. The first two stages were unguided, fin stabilized rockets, and the third stage was spin stabilized. The fourth stage, which was the satellite, consisted of a few diagnostic instruments powered by a small spherical rocket engine. As a result of its simple construction, the L-4S was the least expensive space booster in the world.
The first four launches ended all in failures. On February 11, 1970, the fifth Lambda-4S took off from Kanageshima Space Center. The booster launched the Oshumi satellite (named for the peninsula from which it was launched) to into orbit. The satellite consisted of the fourth stage rocket engine and nine kg of instruments including thermometers, accelerometers and transmitters. Oshumi had a highly elliptical orbit, ranging in altitude from a perigee of 337 km to an apogee of 5151 km. Oshumi transmitted data for only the first seven 144-minute orbits.
The Lambda rocket was never meant as an operational launch vehicle. The L-4S/Oshumi launcher proved the techniques utilized in orbiting satellites with the Mu booster.