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)

Garbage pickers collect ride on donkey cart while looking for recyclable materials at a rubbish dump in the outskirts of Baghdad, Iraq, August 23, 2016. Despite its huge untapped oil and gas reserves and steadily rising oil output and revenue, 23 percent of the population live below the poverty line, according to the Ministry of Planning. (Photo by Khalid al Mousily/Reuters)

“When I was 8 years old, my parents paid a smuggler to take me across the Himalayas, a weekslong walk over the mountains from Tibet to India. It was a trek that tens of thousands of other Tibetans have taken since the Dalai Lama fled a failed 1959 uprising against Chinese rule. My parents must have had their reasons to send me here; they must have had the best of intentions. But 18 years later, I still don't know why they did it. They are not political people. They are small farmers who raise barley and a few yak in a rural area not far from Lhasa, the Tibetan capital. I have not seen them since I left...”. – Tsering Topgyal via The Associated Press. (Photo by Tsering Topgyal/AP Photo)

Jorge, an immigrant from Mexico, dressed as the Sesame Street character Elmo rests in Times Square, New York July 29, 2014. Elmo and Cookie Monster have long delighted young viewers on TV's “Sesame Street”, but the recent antics of New York street performers dressed as the beloved characters have drawn the ire of city officials and now the show's producers. Sesame Workshop, which owns the rights to Big Bird, Ernie and the assorted puppet monsters on the 45-year-old program, said on July 29, 2014 it was drafting plans to stop performers who dress up as the characters from appearing in Times Square, where they pose for photos with tourists and then demand tips. (Photo by Eduardo Munoz/Reuters)

“The saguaro (scientific name Carnegiea gigantea) is a large, tree-sized cactus species in the monotypic genus Carnegiea. It is native to the Sonoran Desert in the U.S. state of Arizona, the Mexican state of Sonora, a small part of Baja California in the San Felipe Desert and an extremely small area of California, U.S. The saguaro blossom is the State Wildflower of Arizona”. – Wikipedia

Photo: Daniel Appel (L), a firefighter with Engine 84 from the Lassen National Forest in California and Mike Hallen, (R), Arizona representative of the National Register of Big Trees, measure the circumference of this Saguaro cactus called the "Grand One," in the Tonto National Forest on July 1, 2005 35 miles north of Phoenix, near Carefree, Arizona. The cactus, estimated to be more than 200 years old, measures a circumference of 7 feet, 10 inches (2.4 meters) and stands 46 feet high (14 meters). The cactus was burned in the Cave Creek Complex fire and may not survive. It was once the largest Saguaro in the world, two others have been found recently that have tied it's measurements. The fire has burned more than 214,000 acres of the Sonoran desert. (Photo by Jeff Topping/Getty Images)

Mayu adjusts Koiku’s kimono, as Koiku wears a protective face mask while posing for a photograph, before they work at a party where they will entertain with other geisha at Japanese luxury restaurant Asada in Tokyo, Japan, June 23, 2020. (Photo by Kim Kyung-Hoon/Reuters)

Topless protesters from the organization PETA (People for the Ethical Treatment of Animals) stand with “banderillas” filled with red powder as about 100 people rally in front of the town hall square in Pamplona, Navarra, northern Spain, demonstrating against the treatment of fighting bulls in the Fiesta de San Fermin, 05 July 2017. The renowned eight-day festival made famous by Ernest Hemingway's 1926 novel “The Sun Also Rises” has running-with-the-bulls and a bullfight each day for the fair, which begins at noon on 06 July 2017. (Photo by Jim Hollander/EPA)

A schoolgirl stands next to the Kenya-Uganda railway line during the partial reopening of schools, after the government scrapped plans to cancel the academic year due to the coronavirus disease (COVID-19) pandemic, in Kibera slums of Nairobi, Kenya on October 12, 2020. (Photo by Thomas Mukoya/Reuters)