An European has developed RADIUS (Range Adaptable Device Incorporating Unique Scaling) which allows high explosive bombs their yield (size of the explosion) set by the operator just before use. RADIUS was successfully tested using two 227 kilograms (500 pound). Each of these bombed contains about 45 kg (100 pounds) of high explosives. One of the modified bombs was detonated at full power setting, creating an explosion similar to an ordinary Mk 82,bomb while the other one was detonated at the lowest, 10 percent setting, with the expected, smaller output, roughly similar to that of a 155mm (6 inch) artillery shell. So far this is considered to be the upper end of size of warhead to which this technology is applicable, the low one being about 1 kg (2.2 pounds) missile warheads.
Once the RADIUS technology is fully developed, which is expected to happen by the end of the decade weapons using RADIUS will have five different explosion yield settings, lowest one being 10% of the explosive charge’s full power. RADIUS can be used in artillery shells, bombs and the warheads of rockets and guided missiles. RADIUS will be most useful on guided weapons. The developer will not release details of how RADIUS works but it appears to involve controlling deflagration during detonation. The concept has long been known but getting it work have been very difficult.
Although reducing the explosive power of various munitions is not a particularly needed capability in conventional wars in which all parties abide by the laws of war, the RADIUS technology will certainly find buyers among countries taking part in the war on terror. Terrorist organizations are aware of how averse Western nations are towards collateral damage among civilians and are willing to exploit them as human shields at every opportunity. ISIL (Islamic State in Iraq and the Levant) has done that for over a year about 75 percent of U.S. bombing missions against them returned to base without using any of their weapons. The main reasons for this was that the perceived risk of harming civilians was seen as too high. The warplanes usually carry guided bombs big enough to be effective against fortified buildings, vehicle groupings or troop concentrations, but weapons like this, despite being precise enough to hit within few meters of designated target, can still endanger civilians up to several hundred meters distant. That’s because explosives create blast and fragments that have range proportional to the size of the explosion. This makes attacking targets anywhere near towns or villages a tough political choice. On the other hand, smaller bombs that could be safely used closer to dwellings aren’t very effective against field targets while not being much cheaper than the larger ones. Thanks to RADIUS mission planners will not have to try to guess precisely what weapons an aircraft need during its next flight, because the pilot will be able to set the bomb’s power to just what he needs by the push of a button. --Adam Szczepanik