抄録
When a projectile flies at supersonic speed in a ram-accelerator tube, which is filled with pre-mixed gas of fuel and oxidizer, the gas mixture is compressed and ignited by the shock waves which are formed around the projectile to yield the thrust. This concept has a good scalability and is capable of accelerating payloads of various mass. Utilizing the advantages of the ram accelerator, two direct launch systems are conceptually designed. One of these is a launch system to a low earth orbit and the other is a middle altitude meteorological observation launch system. The LEO launch system is aiming to accelerate a projectile of 2000 kg to the velocity of 6 km/s. To attain this velocity the launch tube of nearly 900 m is needed. The launcher will be located on the western side of the mountain near the equator aimed at 20 degrees from horizontal and towards the east. In the meteorological observation launch system the projectile mass considered is 12 kg and the launch velocity is 1.8 km/s. Required length of the tube in this case is about 35 m. Because of the launch angle of 80 degrees taken from horizontal, it is probably suitable to built the launcher under the ground. To realize the LEO launch system, there are quite a few technical challenges, such as the experimental demonstration of the velocity of 6 km/s, the development of an on-board propulsion system for orbiting the projectile, and solutions of the structural problems of constructing a huge ram accelerator system. On the other hand, the meteorological observation launch system is simpler and smaller than the LEO launch one and it seems that there is no critical problem preventing it from being realized.
