Engineers at the US National Aeronautics and Space Administration (NASA) have developed a launch mechanism that includes acceleration with a "rail gun" and climb with a hypersonic engine.
The proposed launch complex is based on the old idea of a railgun (railgun) - a mass accelerator, which is an electrically conductive rails along which the vehicle is directed. Acceleration occurs under the action of a magnetic field excited in the rails.
The linear engine used in this case with a capacity of 240 thousand liters. with. (almost 180 MW) is capable of accelerating a spacecraft to a speed of Mach 1.5 (1,770 km / h) in less than a minute in a section of 3.2 km. The resulting overload does not exceed 3g, which means that the flights will be manned.
At the second stage of acceleration, a hybrid supersonic / hypersonic ramjet engine (ramjet) is switched on, thanks to which the device will be able to reach a speed 10 times higher than the speed of sound. At an altitude of about 60 km, where there is not enough air to create jet thrust, the ramjet will be disconnected. The design will allow the engine to descend on its own and return to its starting point.
Rocket engines will launch the spacecraft directly into orbit. After completing the mission (for example, delivering the cargo), he will be able to return to Earth. Already in a day, you can carry out a restart.
The project costs are estimated at about $ 1 billion. The cost of each launch will be significantly lower than for shuttles, due to the savings on rocket fuel. In addition, such a system allows you to launch dissimilar vehicles in a short period of time. Finally, it is less dangerous for astronauts.
Of all the currently existing technologies for launching into space without the use of launch vehicles, this is the most developed, according to one of the project participants, physicist from the Kennedy Space Center Stan Starr.
Parts of the system are already being developed: the US Navy is testing the railgun (albeit as a ship weapon), and Boeing and Pratt & Whitney Rocketdyne are improving ramjet technology on unmanned aerial vehicles (such as the X-51). All the necessary tests can be carried out in the next 10 years, experts say.
At the same time, NASA does not intend to abandon traditional methods of delivery into orbit yet. The agency is now considering a project to create mini-shuttles without closing the door to other launch programs using carrier rockets.
