Clouds float over an open field January 3, 2007 in Shirley Heights, Antigua. (Photo by Joe Raedle/Getty Images)

In this January 12, 2016 photo, an abandoned boat lies on the dried up lake bed of Lake Poopo, on the outskirts of Untavi, Bolivia. Drought caused by the recurrent El Nino meteorological phenomenon is considered the main driver of the lake's demise. Along with glacial melting, authorities say another factor is the diversion of water from Poopo's tributaries, mostly for mining but also for agriculture. (Photo by Juan Karita/AP Photo)

Models display a creation by K-Lynn Lingerie during a fashion show in the Lebanese capital Beirut on April 24, 2016. (Photo by Anwar Amro/AFP Photo)

“Light From Heaven”. Taken around Mount Bromo, East Java, Indonesia in the morning. Photo location: East Java, Indonesia. (Photo and caption by Pimpin Nagawan/National Geographic Photo Contest)

ATTENTION! All pictures are presented in high resolution. To see Hi-Res images – just TWICE click on any picture. In other words, click small picture – opens the BIG picture. Click BIG picture – opens VERY BIG picture.

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)

Police officers clear the area near Borough market at London Bridge on June 3, 2017 in London, England. Police have responded to reports of a van hitting pedestrians on London Bridge in central London. (Photo by Dan Kitwood/Getty Images)

Prince Charles, Prince of Wales (R) and Camilla, Duchess of Cornwall (L) visit Seppeltsfield Winery in Barossa Valley, Australia, 10 November 2015. The royal couple are on a 12-day tour visiting seven regions in New Zealand and three states and one territory in Australia. (Photo by Daniel Kalisz/EPA)

Afghan security stands guard as a tractor eradicates a field of young poppy plants May 25, 2011, in Argu District, Badakshan, Afghanistan. (Photo by Paula Bronstein/Getty Images)