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 Thai performer puts his head inside a crocodile's mouth during a media preview performance as part of preparation to reopen Samutprakarn Crocodile Farm and Zoo in Samut Prakan province, Thailand, 19 March 2024. (Photo by Rungroj Yongrit/EPA)

People search for shells on a beach in Sittwe, Rakhine State, Myanmar, 17 September 2020. International Coastal Cleanup Day is observed annually on the third Saturday of September and will occur on 19 September this year. (Photo by Nyunt Win/EPA/EFE/Rex Features/Shutterstock)

Slovenian photographer Peter Gedei started caving 25 years ago and has carried a camera with him on every trip getting stunning pictures from his travels, capturing the ice formations, tight chambers and beautiful halls. Photo: The Ice Cave in Postojna, Slovenia. (Photo by Peter Gedei/Caters News)

Models present creations by Colombian designer Guio Di Colombia during the Inclusion catwalk and Expomujer in Cali, Colombia, November 3, 2016. The catwalk includes models of all sizes, races, sexuality and physical ability. (Photo by Jaime Saldarriaga/Reuters)

A tank's barrel is seen on the course of the Tank Biathlon competition during the International Army Games 2016 in Alabino, outside Moscow, Russia, July 30, 2016. (Photo by Maxim Zmeyev/Reuters)

Juventus' Italian forward Cristiana Girelli celebrates after scoring an equalizer during the UEFA Women's Champions League Group A football match between Juventus and Wolfsburg on November 09, 2021 at the Juventus stadium in Turin. (Photo by Marco Bertorello/AFP Photo)

This picture taken on September 3, 2014 shows a man taking pictures of floodwater released from the Three Gorges Dam, a gigantic hydropower project on the Yangtze river, in Yichang, central China's Hubei province, after heavy downpours in the upper reaches of the dam caused the highest flood peak of the year. Eleven people died and 27 others are missing after torrential rains battered southwest China's Chongqing, a municipality in the upper reaches of the Three Gorges Dam, causing thousands of houses to collapse, state media said. (Photo by AFP Photo/Stringer)