First it was brute force: throwing stones, then arrows and spears. Then chemistry arrived and we learned about gunpowder. Later we met, discovered or created new types of increasingly powerful explosives. And now it’s physics’s turn. A new test carried out by the Franco-German company ISL, has demonstrated the operation of a new generation electromagnetic cannon, a technology that completely dispenses with gunpowder and uses only electricity to accelerate a projectile to hypersonic speeds. And for the first time they have tested it outside the laboratory.
To understand how this type of device, also known as railguns, It is advisable to forget about weapons for a moment. The physical principle is much more similar to that of a magnetic levitation train. Instead of an explosion, the projectile is placed between two metal rails through which a gigantic electric current circulates.of several million amperes for a few thousandths of a second.
This current generates an intense magnetic field that pushes the projectile forward with enormous force. There are no gases expanding, no combustion… Just electricity converting directly into speed.
In this case, The maximum speed reached by the projectiles was 5,400 km/h. The system uses energy of about 1 megajoule, which is relatively modest compared to some previous US projects. This type of weapon has several advantages: much cheaper ammunition, hypersonic speeds, long range…Although not everything is good news: the wear and tear of the weapon (of the rails) is greater and the need for large doses of energy means that it is not a simple implementation.
When a projectile weighing several kilos, fired by an electromagnetic cannon, hits a target at several kilometers per second, the effect is devastating even if it is only made of metal since Energy increases with the square of speed. That means doubling the speed quadruples the impact energy.
“The move to open field testing – points out ISL in a statement – represents a significant and indispensable advance beyond laboratory work: it is where a technology begins to be evaluated in conditions closer to those of its final use. This technology has long aroused the interest of defense researchers, including as a possible long-term contribution to countering hypersonic threats: missiles and maneuverable reentry vehicles that are proliferating and increasingly testing the limits of current kinetic interceptors. An electromagnetic launcher, in principle, offers a different answer: one that does not rely on chemical propulsion and can adapt to multiple trajectories. The next step will be exploitation: higher energy levels and greater free flight distance.”