A long exposure image of embers flying off burnt out trees following the wind driven wildfire ranging in the mountain area near Rancho Cucamonga late 30 April 2014. Earlier in the day more than 1,500 homes were evacuated as the Etiwanda fire charred around 1,000 acres in San Barnardino National Forest. (Photo by Stuart Palley/EPA)

(L-R) Recording artists Jessie J, Ariana Grande, and Nicki Minaj perform onstage during the 2014 MTV Video Music Awards at The Forum on August 24, 2014 in Inglewood, California. (Photo by Michael Buckner/Getty Images)

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)

Three very colouful alpacas enjoy the hot weather at Toft Farm, Rugby, on July 19, 2013. (Photo by Caters News)

An Afghan policeman stands guard as smoke and flames rise from the site of a huge blast struck near the entrance of Kabul's international airport, in Kabul on August 10, 2015. A huge blast struck near the entrance of Kabul's international airport on August 10 during the peak lunchtime period, officials said, warning that heavy casualties were expected. “The explosion occurred at the first check point of Kabul airport”, said deputy Kabul police chief Sayed Gul Agha Rouhani. (Photo by Shah Marai/AFP Photo)

Job seekers carry a woman who fainted at the Indonesia Spectacular Job Fair 2015 at Gelora Bung Karno stadium in Jakarta August 12, 2015. Indonesia's gross domestic product grew at 4.67 percent in the second quarter, its slowest pace in six years. Since he took office last October, Widodo's government has passed a raft of measures aimed at boosting industry and consumption that have been criticized by investors as protectionist. (Photo by Reuters/Beawiharta)

Robert Burck, a street performer known as “The Naked Cowboy” dips a woman as he poses for a photo in Times Square in New York, U.S., August 4, 2016. (Photo by Carlo Allegri/Reuters)

Men push a motorbike through a street flooded by a river that overflowed from heavy rains caused by Hurricane Matthew in Leogane, Haiti, Wednesday, October 5, 2016. Rescue workers in Haiti struggled to reach cutoff towns and learn the full extent of the death and destruction caused by Hurricane Matthew as the storm began battering the Bahamas on Wednesday and triggered large-scale evacuations along the U.S. East Coast. (Photo by Dieu Nalio Chery/AP Photo)