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)

Actress Marilyn Monroe poses for a portrait in a bathing suit and high heels with a bottle of Coca-Cola in a glass on a table behind her in circa 1953. (Photo by Michael Ochs Archives/Getty Images)

A Pegasus airplane is seen stuck in mud as it skidded off the runway after landing in Trabzon Airport, Turkey early Sunday on January 14, 2018. A passage plane which belongs to Turkey's Pegasus Airlines skidded off the runway of Trabzon airport Saturday and ended up halfway down a steep slope into the Black Sea, Turkish media reported on Sunday. 162 passengers and crew on board were safely evacuated. (Photo by Hakan Burak Altunoz/Anadolu Agency/Getty Images)

An Indian soldier from the international peace keeping force (IPKF) instructs young Sri Lankan recruits in shooting, part of the training given to the citizen's volunteer force in the North-Eastern Sri Lankan city of Batticaloa, September 28, 1989. (Photo by Barbara Walton/AP Photo)

Labourers break fast outside a shop in a market on the first day of the Muslim holy month of Ramadan in Karachi, Pakistan June 7, 2016. (Photo by Akhtar Soomro/Reuters)

Ukrainian servicemen are seen training with a BMP-2 in Donetsk Region, Ukraine on February 10, 2022. (Photo by Wolfgang Schwan/Anadolu Agency via Getty Images)

A motorist drives a car through a flooded expressway in Brooklyn, New York early on September 2, 2021, as flash flooding and record-breaking rainfall brought by the remnants of Storm Ida swept through the area. (Photo by Ed Jones/AFP Photo)

People gather beneath rainbow lights following Cinespia’s screening of “The Wizard of Oz” at Hollywood Forever Cemetery, presented by Amazon Studios & Prime Video, on July 31, 2021 in Los Angeles, California. Summer screenings have returned to the iconic cemetery after a hiatus amid the pandemic last summer. Actress Judy Garland is laid to rest at the cemetery where many movie legends are buried. (Photo by Mario Tama/Getty Images)