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 woman dressed for la “La Diablada” festival, walks down a road in Pillaro, Ecuador, Friday, January 6, 2017. Local legend holds that anyone who adopts a costume for the celebration and wears it at the event six years in a row will have good luck. (Photo by Dolores Ochoa/AP Photo)

Rescuers work at the accident scene on a bridge on July 24, 2011 in Wenzhou, Zhejiang Province of China. The train from Hangzhou to the city of Wenzhou derailed on a bridge that is 10 m above the field in Shuangyu Town of Wenzhou city at 8:34 p.m on Saturday. The first four coaches and the 15th and 16th coaches of the train went off the line killed 32 and injured 191 people. (Photo by ChinaFotoPress/Getty Images)

This photo taken on December 2, 2023 shows pandas eating inside their enclosure at a zoo in China's southwestern Chongqing municipality. (Photo by AFP Photo/China Stringer Network)

People take photos during the Loy Krathong festival which is held as a symbolic apology to the goddess of the river in Chiang Mai, Thailand, November 19, 2021. (Photo by Soe Zeya Tun/Reuters)

A woman shoots her rifle at a forest shooting range near the village of Visnova, Czech Republic, June 9, 2016. (Photo by David W. Cerny/Reuters)

Sparkler fireworks are created by Palestinian children in the al-Zaytoun district on the east of Gaza City on March 28, 2023 during Ramadan. The fireworks, which are made with steel wire wool, are part of the celebrations in the Palestinian enclave during the Muslim holy month. (Photo by Ahmad Hasaballah/IMAGESLIVE via ZUMA Press Wire/Rex Features/Shutterstock)

“Double head vulture”. On the day of windy days during raptors migration some people in my country start to catch these tired raptors, so in this day we go to photograph some raptors and we saw these tow tired vultures, so we start to drag them away from the hunters until they reach a good hidden place, to make them safe until they start a new journey. Photo location: Kuwait. (Photo and caption by Mohd Khorshed/National Geographic Photo Contest)