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 giant sinkhole in Guatemala City, on May 31, 2010. More than 94,000 were evacuated as the storm buried homes under mud, swept away a highway bridge near Guatemala City and opened up several sinkholes in the capital. (Photo by Casa Presidencial/Reuters via The Atlantic)

Grumpy Cat attends the “Grumpy Cat: A Grumpy Book” Book Event at Bookends Bookstore on October 16, 2013 in Ridgewood, New Jersey. (Photo by Michael N. Todaro/WireImage)

1st prize in the People Observed Portraits Stories category. Carla Kogelman, the Netherlands. The photo shows Hannah and Alena, two sisters living in the rural village of Merkenbrechts, Austria. (Photo by Carla Kogelman/World Press Photo)

Three prostitutes lean out of a window in Santiago, Chile, in an attempt to entice customers inside, circa 1950. (Photo by Three Lions/Getty Images)

A male sea lion Leo writes the word of tiger in Chinese character at a New Year's attraction to celebrate the Year of the Tiger at the Hakkeijima Sea Paradise aquarium in Yokohama, suburban Tokyo on Monday, January 3, 2022. The calligraphy attraction by the sea lion will be carried through January 31. (Photo by Yoshio Tsunoda/AFLO/Rex Features/Shutterstock)

A harlequin inflatable doll, part of decorations for the upcoming carnival celebrations, lays in a plaza in Caracas, Venezuela, Tuesday, February 22, 2022. (Photo by Ariana Cubillos/AP Photo)

Gypsies gather at Appleby in Cumbria, United Kingdom on August 12, 2021, for the biggest horse fair of its kind in Europe, which lasts till Sunday. Typically the fair takes place in June, although COVID has pushed it back to August in 2021. In the region of 30,000 people are expected to attend. (Photo by Chris Strickland/Alamy Live News)