Over 30 Douglas C-47 Skytrains (Dakotas) making final preparations for flight formation practice before the 75th D-Day Anniversary flight to Normandy in Duxford, England on June 4, 2019. (Photo by UK Air Force Images)

Sinabung mount spews ash to the air during an eruption near from Karo, North Sumatra on January 7, 2014. An Indonesian volcano that has erupted relentlessly for months shot volcanic ash into the air 30 times on January 4, forcing further evacuations with more than 20,000 people now displaced, an official said. (Photo by Sutanta Aditya/AFP Photo)

In this undated photo released Tuesday April 13, 2021, by Russian Defense Ministry Press Service, A Tu-160 strategic bomber of the Russian air force is shown on a training mission somewhere in Russia. Russian Defense Minister Sergei Shoigu on Tuesday described a massive military buildup in western Russia as part of drills intended to check the armed forces' readiness amid the threats posed by NATO. (Photo by Vadim Savitsky/Russian Defense Ministry Press Service via AP Photo)

Indonesian Air Force soldiers from the Paskhas corps shout slogans during a rehearsal for a ceremony marking the 70th anniversary of Indonesia's military in Cilegon, Banten province, October 3, 2015. Indonesia will celebrate the anniversay of its military on October 5. (Photo by Reuters/Beawiharta)

Al Fursan, the UAE Air Force aerobatic display team, perform during the opening of the Dubai Airshow in United Arab Emirates, Sunday, November 8, 2015. Dubai Airshow took off today to a slow start amid little expectations of major orders to match the multi-billion-dollar sales generated at the last edition of the biennial fair. (Photo by Kamran Jebreili/AP Photo)

Arizona Cardinals cheerleader Claire Thorton, center, smiles as Air Force Capt. Eric Straub proposes to her during the first half of an NFL football game against the Washington Redskins, Sunday, October 12, 2014, in Glendale, Ariz. Thorton accepted the proposal. (Photo by Rick Scuteri/AP Photo)

A man watches Israeli Air Force planes fly over the Mediterranean Sea from a beach at Tel Aviv during an aerial show as part of celebrations for Israel's Independence Day to mark the 66th anniversary of the creation of the state, May 6, 2014. (Photo by Nir Elias/Reuters)

A girl poses at an entrance of her house next to a bomb dropped by the U.S. Air Force planes during the Vietnam War, in the village of Ban Napia in Xieng Khouang province, Laos September 3, 2016. From 1964 to 1973, U.S. warplanes dropped more than 270 million cluster munitions on Laos, one-third of which did not explode, according to the Lao National Regulatory Authority. (Photo by Jorge Silva/Reuters)