North Koreans who signed up to join the army train in the midst of political tension with South Korea, in this undated photo released by North Korea's Korean Central News Agency (KCNA) in Pyongyang August 23, 2015. Top aides to the leaders of North and South Korea resumed talks on Sunday after negotiating through the night in a bid to ease tensions involving an exchange of artillery fire that brought the peninsula to the brink of armed conflict. (Photo by Reuters/KCNA)

A young woman holds a weapon during a basic combat training for civilians, organized by the Special Forces Unit Azov, of Ukraine's National Guard, in Mariupol, Donetsk region, eastern Ukraine, Sunday, February 13, 2022. The United States is evacuating almost all of the staff from its embassy in Kyiv as Western intelligence officials warn that a Russian invasion of Ukraine is increasingly imminent. (Photo by Vadim Ghirda/AP Photo)

People in full medieval armor take part in a combat at Central Park in New York, U.S., August 14, 2021. (Photo by Eduardo Munoz/Reuters)

Levi Dinmore, 8, gets a COVID-19 test at a Sameday Health drive-through testing site in Bethesda, Maryland, U.S., December 22, 2021. (Photo by Evelyn Hockstein/Reuters)

A guest arrives before the Blumarine show during Milan Fashion Week Spring 2019 in Milan, Italy, September 21, 2018. (Photo by Stefano Rellandini/Reuters)

The R.C. Bush Pilots club was started in 1981, for those who enjoy flying radio control (RC) model planes. It’s one of the largest clubs in Florida, and calls Phil Wherry Field in West Palm Beach home. Photo: Professional pilot and remote control plane enthusiast Bob Rembert prepares to start the propeller of a 1/4 scale Edge 540 remote control, gas powered plane. (Photo by Bill Ingram/The Palm Beach Post)

Eurocopter's X³ high-speed hybrid helicopter demonstrator performs, September 6, 2010. The Eurocopter X³ (X-Cubed) is an experimental high-speed compound helicopter developed by Eurocopter (now Airbus Helicopters). A technology demonstration platform for Eurocopter “high-speed, long-range hybrid helicopter” or H³ concept, the X³ achieved 255 knots in level flight on 7 June 2013, setting an unofficial speed record for a helicopter. (Photo by Reuters/HO/Eurocopter/Penna)