A police officer from an explosive disposal unit takes part in a security drill ahead of next year's general election in Sidoarjo, East Java, on August 23, 2023. (Photo by Juni Kriswanto/AFP Photo)

Performers are seen as a 90-year old spruce tree cut down in the woods of the Shchyolkovsky District in Moscow Region, Russia on December 16, 2021 is sent to Moscow. The almost 28-metre high tree will be put up at the Moscow Kremlin's Sobornaya (Cathedral) Square this New Year and Christmas. (Photo by Vasily Fedosenko/TASS)

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)

An Orangutan named Elze walks in the Biopark of Rio during a media tour in Rio de Janeiro, Brazil, Thursday, March 18, 2021. The park was closed to the public for renovations to convert the city zoo into a center for biodiversity conservation and will reopen to the general public at the end of March. (Photo by Bruna Prado/AP Photo)

In the spring of 1965, within weeks of 3,500 American Marines arriving in Vietnam, a 39-year-old Briton named Larry Burrows began work on a feature for LIFE magazine, chronicling the day-to-day experience of U.S. troops on the ground – and in the air – in the midst of the rapidly widening war. The photographs in this gallery focus on a calamitous March 31, 1965, helicopter mission; Burrows’ “report from Da Nang”, featuring his pictures and his personal account of the harrowing operation, was published two weeks later as a now-famous cover story in the April 16, 1965, issue of LIFE.

Photo: Man your battle stations: The crew chief of helicopter Yankee Papa 13, lance corporal James C. Farley, mans an M-60 machine gun during a mission near Da Nang, Vietnam on March 31, 1965. (Photo by Larry Burrows/Time & Life Pictures)

A staff member demonstrates how she puts on the helmet of a mock space suit at the C-Space Project Mars simulation base in the Gobi Desert outside Jinchang, Gansu Province, China, April 17, 2019. The facility – comprising several interconnected modules including a greenhouse and a mock decompression chamber – opened its doors to the public. (Photo by Thomas Peter/Reuters)

British Prime Minister Boris Johnson visits the Pavegen stand, a company that converts footsteps into energy, at the Innovation Zone during the UK-Africa Investment Summit in London, Britain on January 20, 2020. (Photo by Leon Neal/Pool via Reuters)

Professional dancer Sandy Lewis, from Louisiana, performs with his dance partner Marti Gasol, as they train in the street due to restrictions to do it indoor, in Barcelona on Wednesday, November 11, 2020 as Spain continue with new measures against the COVID-19. (Photo by Emilio Morenatti/AP Photo)