If you have ever seen an aircraft close up, you may have noticed that some of them have strange chunks of metal hanging out at the back. This is because in aircraft, counterweights use heavy metals to offset weight.
When it comes to aircraft, counterweights are used to offset weight. The aircraft's exact design depends on its function and size, but there are a few constants:
Depleted uranium (DU) is a type of uranium that has less of the fissile U-235 isotope than natural uranium. It's a byproduct of the uranium enrichment process, which creates fuel for nuclear power plants and nuclear weapons. Natural uranium is a mix of U-235 and U-238 isotopes, with U-235 being the fissile isotope. In order to make it suitable for use in a reactor or bomb, you need to enrich it so there's more U-235 than anything else.
DU is very dense and therefore makes an excellent choice for aircraft counterweights. Aircraft have to be designed with counterweights in order to maintain center of gravity within the allowable specification.
DU is used in aircraft as a counterweight to offset the weight of fuel, passengers and cargo.
Due to the high radiation and toxicity of DU, the aviation industry has been using alternatives. DU is banned in some countries, so it's being phased out in the aviation industry. Alternatives include tungsten, lead and concrete. Tungsten is a low-density material that weighs about twice as much as steel but has a higher melting point; it's also used for bullet tips. Lead is lighter than both tungsten and concrete and can be molded into different shapes such as cubes or spheres; however, it isn't very strong compared with other materials that have been used for counterweights in aircrafts like concrete which was commonly used until about 30 years ago when stronger materials were developed for counterweights
It's important to note that the ban does not apply to existing aircraft, only new ones.
Depleted uranium, or DU, is an element heavy metal that has been used in counterweights on aircraft since the 1970s. While it's not radioactive and doesn't pose any risk of harming passengers or crew members, DU is toxic when ingested or inhaled.
It's also controversial: many believe that using depleted uranium in aircraft causes more harm than good because of its potential to contaminate water supplies and cause cancer if accidentally ingested by civilians.
With the increased use of composites and other materials in aircraft construction, there is less need for heavy metals such as depleted uranium. This means that you are likely to see fewer aircraft with DU counterweights in the future. There are also concerns about DU's toxicity when it comes into contact with humans or animals, so manufacturers are looking for alternative ways to make their planes fly safely without putting passengers at risk from radiation poisoning when flying over populated areas.