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)

Pakistani supporters of cricketer-turned politician Imran Khan and Canadian cleric Tahir ul Qadri beat a riot policeman during an anti-government protest in Islamabad on September 1, 2014. Hundreds of protesters trying to topple Pakistan's government briefly seized the state broadcaster on September 1, intensifying the political crisis gripping the nuclear-armed nation. Deadly clashes since the weekend have raised the spectre of military intervention which gained ground after one disillusioned opposition leader said the protesters were acting according to a plan devised by the army. (Photo by Aamir Qureshi/AFP Photo)

A member of the National Gendarmerie Intervention Group (GIGN) deactivates a bomb from a supposed terrorist during a training exercise in the event of a terrorist attack in collaboration with Recherche Assistance Intervention Dissuasion (RAID) and Research and Intervention Brigades (BRI) in presence of the French Interior minister Bernard Cazeneuve at la Gare Montparnasse, in central Paris on April 20, 2016. (Photo by Miguel Medina/Reuters)

A spectator waits for the start of the Jeremy Scott show during Fashion Week in New York, Thursday, February 8, 2018. (Photo by Andres Kudacki/AP Photo)

Former leader of Britain's UKIP party, Nigel Farage (C) reacts as he speaks with Italian-Swedish MEP Anna Maria Corazza Bildt (L) and British Journalist Rachel Johnson during a panel discussion at a conference on Brexit, at the Saatchi Gallery in London on February 19, 2019. The British government on Friday dismissed as a “hiccup” its latest parliamentary defeat over Brexit, saying it would press on with trying to renegotiate its EU divorce deal as exit day looms in just six weeks. (Photo by Tolga Akmen/AFP Photo)

Freya Smith aged three, leads one of Erth’s giant dinosaur puppets across the road on August 6, 2019 in Edinburgh, Scotland. Australian theatre company Erth presents their best-selling show Dinosaur’s Zoo as part of Underbelly’s Fringe programme. Featuring giant dinosaur puppets which walk, roar and blink like the real thing, Dinosaur’s Zoo is a perfect example of edutainment for children of all ages, taking place at the McEwan Hall every day of the Fringe at 11am. (Photo by Jeff J. Mitchell/Getty Images)

A woman uses a face masks as a preventive measure against the spread of the new coronavirus, COVID-19, in Bogota, on March 19, 2020. Colombia will block all international flights from Monday for 30 days, President Ivan Duque announced on Thursday. (Photo by Raul Arboleda/AFP Photo)

A South African police officer speaks to residents of the densely populated Alexandra township east of Johannesburg Friday, March 27, 2020. (Photo by Jerome Delay/AP Photo)