“Jet Man” Richard Browning demonstrating Gravity, a human jet suit system, at the opening of the Army's Personnel Conference held at Farnborough International Conference Centre, Farnborough, Hampshire on Tuesday, November 2, 2021. (Photo by Steve Parsons/PA Images via Getty Images)

Soldiers of China's People's Liberation Army (PLA) jump as part of their winter training in temperature of negative 26 degrees Celsius at China's border with Russia in Heihe, Heilongjiang province, December 14, 2015. (Photo by Reuters/Stringer)

A female soldier takes part in a training for women at the Tolemaida Military Air Base in Tolemaida, Colombia, on May 16, 2023. The last time the Colombian Army enlisted women in their ranks was in 1993. Now, 30 years on, more than 1,200 women voluntarily joined the military service in the country. (Photo by Raúl Arboleda/AFP Photo)

Indian Army Jawan (soldiers) of the “ASC Tornadoes” daredevil bike team perform during Independence Day celebrations in Bangalore, India, 15 August 2024. India celebrated its 78th Independence Day on 15 August. (Photo by Jagadeesh N.V./EPA)

Auxiliary Territorial Service (ATS) plotters at work at Coastal Artillery Headquarters in Dover, December 1942. The Auxiliary Territorial Service was the women's branch of the British Army during the Second World War. It was formed on 9 September 1938, initially as a women's voluntary service, and existed until 1 February 1949, when it was merged into the Women's Royal Army Corps. The ATS had its roots in the Women's Auxiliary Army Corps (WAAC), which was formed in 1917 as a voluntary service. During the First World War its members served in a number of jobs including clerks, cooks, telephonists and waitresses. The WAAC was disbanded after four years in 1921. (Photo by Ted Dearberg/IWM/PA Wire)

Russian soldiers from 34th motorized infantry mountain brigade, 58th Army, prepare to evacuate a fellow soldier acting as an injured person during a drill at the Darial range outside Russia's city of Vladikavkaz, July 28, 2010. (Photo by Kazbek Basayev/Reuters)

North Korean leader Kim Jong Un (front) stands on the conning tower of a submarine during his inspection of the Korean People's Army (KPA) Naval Unit 167 in this undated photo released by North Korea's Korean Central News Agency (KCNA) in Pyongyang June 16, 2014. (Photo by Reuters/KCNA)

Dr. P.A. Smithe was sent by the American Red Cross as a doctor and surgeon to work at a hospital in Vienna. He sailed to Europe in December 1915 and returned home in August 1916, according to his daughter, who donated his images to the National World War I Museum. Photo: Turkish army, including cavalry, infantry and artillery. (Photo by Dr. P.A. Smithe/National World War I Museum, Kansas City, Mo.)