Ranger trainees and trainee dogs simulate an ambush against rhino poachers at the Paramount Group Anti-Poaching training and K9 (canine) academy on November 26, 2014 in Magaliesberg, South Africa. One of the largest of its kind in Africa, the Academy will address the ever increasing need for training of Conservation Officers in anti poaching activities, wildlife contraband detection, specialist K9 solutions and Ranger K9 handler training – all of which have proven success rates in combatting and apprehending poachers and their activities. (Photo by Gianluigi Guercia/AFP Photo)

A view of a turtle during an event at the Ministry of Environment in Phnom Penh, Cambodia, 24 June 2020. A Cambodian woman recently bought endangered Royal Turtles from local villagers and gave them to Ministry of Environment. (Photo by Kith Serey/EPA/EFE)

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)

Dancers at the Windmill Theatre in London, England practice a routine wearing gas masks and hard-hats with their costumes, 1940. (Photo by Hulton Archive/Getty Images)

Bogdana, 17, laughs with her boyfriend, Ivan, 19, in Brovary, Ukraine, Sunday, March 20, 2022. Russian forces pushed deeper into Ukraine's besieged and battered port city of Mariupol on Saturday, where heavy fighting shut down a major steel plant and local authorities pleaded for more Western help. (Photo by Vadim Ghirda/AP Photo)

Wildlife officials carry away the carcass of a turtle that was washed ashore at the beach of Angulana, south of Sri Lanka's capital Colombo on June 24, 2021. (Photo by Ishara S. Kodikara/AFP Photo)

The coendou porcupine couple 'Joppi' (L) and 'Fletcher' nibble at a vegetables in their enclosure at the zoo in Frankfurt am Main, Germany, 03 December 2015. Coendou porcupines are nocturnal rodents related to porcupines and guinea pigs and native to the rain forests of Central and South America as well as Trinidad. (Photo by Arne Dedert/EPA)

Activists from climate action group Ocean Rebellion demonstrate in St Ives Harbour, ahead of the G7 summit, in St Ives, Cornwall, Britain, June 9, 2021. (Photo by Tom Nicholson/Reuters)