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 woman dressed up as a zombie takes part in a zombie walk in the Gaslamp Quarter during the Comic Con International convention in San Diego, California July 13, 2012. (Photo by Mario Anzuoni/Reuters)

Protesters begin to gather ahead of the UK Student Climate Network's Global Climate Strike at Millbank in London, England on September 20, 2019. (Photo by Gareth Fuller/PA Images via Getty Images)

In this November 16, 2018, file photo, Duane Townsend, left, shoots a pheasant at Special Friday Pheasant Hunts, sponsored by Southern Tulare County Sportsman's Association, at Lake Success Recreation Area in Porterville, Calif. A Utah man who has been in a wheelchair for more than three decades has created a pheasant hunt for people like him who need help getting into the outdoors. The Daily Herald in Provo reports that Clint Robinson broke his neck after being thrown off a horse at a rodeo 32 years ago. The event called “Wheelchairs in the Wild” pairs people that have physical disabilities with hunters who help them with whatever they need. Many go in off-road vehicles. (Photo by Chieko Hara/The Porterville Recorder via AP Photo/File)

Advanced Space Suit Engineer at NASA Kristine Davis wears the xEMU prototype space suit for the next astronaut to the moon by 2024, during its presentation at NASA headquarters in Washington, U.S., October 15, 2019. (Photo by Carlos Jasso/Reuters)

A toddler dressed as Hindu Lord Krishna takes part in Krishna Janmashtami celebrations at a temple in Kolkata, India, on August 23, 2019. Krishna Janmashtami is an annual Hindu festival that celebrates the birth of Lord Krishna, the eighth avatar of Vishnu. (Photo by Tumpa Mondal/Xinhua News Agency)

A Kurdish fighter from the People's Protection Units (YPG) fires his rifle at Islamic State militants as he runs across a street in Raqqa, Syria, July 2017. (Photo by Goran Tomasevic/Reuters)

Model airplane enthusiasts take part in an event at a model airplane field in Mamak district of Ankara, Turkey on December 30, 2021. Model airplane enthusiasts, each owns different sizes and types of aircrafts, have the opportunity to have fun while training. Weekend meetups also give them an opportunity to help each other on technical issues. (Photo by Dogukan Keskinkilic/Anadolu Agency via Getty Images)