There's a new method developed by scientists from Russia that can improve the thrust generated by laser-propelled systems. When this becomes reality, aircrafts could one day be propelled by beams of light instead of using conventional fuels.
The method was developed by Yuri Rezunkov of the Institute of Optoelectronic Instrument Engineering and Alexander Schmidt of the Ioffe Physical Technical Institute.
The most promising system for laser propulsion is to use the laser ablation process. This involves using a pulsed laser beam to strike a surface, which then causes it to heat up and burn, creating a plasma plume. The outflow coming from the plasma plume creates additional thrust that would power up the spacecraft.
Using this method would mean integrating a laser ablation propulsion system together with the spacecraft's gas blasting nozzles. When the two systems are combined, the speed of the gas that flows out of the system could increase to supersonic speeds. At the same time, it reduces the amount needed in using conventional fuel.
The current maximum speed of a spacecraft is limited by the fuel amount that it carries. In order to achieve higher speeds, more fuel must be burned. Carrying a lot of fuel into space can be inconvenient. However, the amount of fuel carried into space could be reduced if a remotely located laser is used for providing an added propulsive force.
While it is true that the newly found method is promising, it has to be remembered that supersonic gases are unstable. If supersonic gases flow through the gas nozzle in an unstable state, they could cause shock waves and make the inlet of a nozzle choke, thereby reducing thrust.
Decreasing the effects caused by unstable supersonic gases can be achieved with the help of a laser ablation plasma plume. If the latter is redirected, it would then flow close to the interior wall of the nozzle.
"Combining the two systems can increase the speed of the gas flow out of the system to supersonic speeds, while reducing the amount of burned fuel," said Rezunkov.
The Earth-bound lasers would have to be incredibly powerful in order to vaporize metal that comes from hundreds of miles away. This type of technology can easily be used in knocking off satellites and damaging anything that sits around the orbit.
Since a number of Earth-bound technologies rely on these satellites, it would be very difficult to build a machine that is powerful enough to knock these satellites out of the sky.
