Pope John Paul II (1920–2005) is shot by would-be assassin Mehmet Ali Agca in St Peter's Square, 13th May 1981. His attendants help him into his white jeep after the incident. (Photo by Keystone/Hulton Archive/Getty Images)

A demonstrator jumps from a vehicle of the Organisation for Security and Co-operation in Europe (OSCE) during a protest to demand what protesters say is true information from the OSCE about the shelling in Donetsk, Ukraine (since April 2014, the city is the administrative centre of the Donetsk People's Republic), July 23, 2015. The graffiti reads, “Stop moronic war!”. (Photo by Alexander Ermochenko/Reuters)

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 dog sits in the shade of a mangrove tree as a woman uses a fork to dig for shellfish on the reef-mud flats of a lagoon located at South Tarawa in the central Pacific island nation of Kiribati May 23, 2013. Kiribati consists of a chain of 33 atolls and islands that stand just metres above sea level, spread over a huge expanse of otherwise empty ocean. With surrounding sea levels rising, Kiribati President Anote Tong has predicted his country will likely become uninhabitable in 30-60 years because of inundation and contamination of its freshwater supplies. (Photo by David Gray/Reuters)

Pakistani laborers transport the front portion of a vehicle using a handcart at a road in Peshawar, Pakistan, Monday, August 3, 2015. (Photo by Mohammad Sajjad/AP Photo)

Dancers prepare before a performance in the backstage area of the Buick exhibition during the “Auto China 2014” Beijing International Automotive Exhibition in Beijing on April 21, 2014. Leading automakers have gathered in Beijing for the kickoff of China's biggest car show, but lackluster growth and environmental restrictions in the world's largest car market have thrown uncertainty into the mix. (Photo by AFP Photo)