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)

In this March 18, 2015 photo, Andrea, better known as Loira, which is the Portuguese word for “blonde”, poses for a portrait in an open-air crack cocaine market, known as a “cracolandia” or crackland where users can buy crack, and smoke it in plain sight, day or night, in Rio de Janeiro, Brazil. Andrea says she is married and has a home, but she keeps returning to crackland to feed her addiction. (Photo by Felipe Dana/AP Photo)

Police officers introduce a litter of golden retriever puppies to be trained as police dogs during a ceremony at the National Police Academy in La Paz, Bolivia, Monday, August 16, 2021, the date of the feast day for Saint Roch, considered the patron saint of dogs, among other things. (Photo by Juan Karita/AP Photo)

Mahsa Kadkhoda #11 of Team Iran spikes the ball during their semi-final round match against Team Chinese Taipei on day seven of the AVC Cup For Women at PhilSports Arena on August 28, 2022 in Pasig, Philippines. (Photo by Ezra Acayan/Getty Images)

A South American Coati licks a block of frozen fruits at Israel's Safari Zoo in Ramat Gan, north of the Mediterranean coastal city of Tel Aviv, as temperatures reach 35 degrees Celsius on July 13, 2023. (Photo by Jack Guez/AFP Photo)

Sir Argus, centre, with Brian Hayes up, jumps the first during the Guinness Beginners Steeplechase, alongside eventual winner Mars Harper, right, with Sam Ewing up, during day four of the Galway Races Summer Festival at Ballybrit Racecourse in Galway, Ireland on August 3, 2023. (Photo by Seb Daly/Sportsfile)

British rock band Bring Me The Horizon performs at the Reading Music Festival, England, Friday, August 27, 2022. (Photo by Scott Garfitt/Invision/AP Photo)

Slovenia’s Janja Garnbret climbs during a training session in Verd, some 20 km southwest of Ljubljana, on March 27, 2024. The eight-time world champion is looking to win another gold medal at the Paris 2024 Olympics Games this summer, just like she did in Tokyo 2020 when the sport debuted at the Olympics. (Photo by Jure Makovec/AFP Photo)