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)

“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)

“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)

A dead crocodile is seen on Huangsha Seafood Market in Guangzhou, Guandong Province, China, 22 January 2018. Tsukiji Market of China or Huangsha Seafood Market is biggest one in Southern China and one of the biggest in China, as there are literally hundreds of different varieties of fish and seafood scattered throughout the market. (Photo by Aleksandar Plavevski/EPA/EFE)

A white crab spider hides between the petals of a rain spotted rose blossom in the garden of a home near Oakland in southwestern Oregon on August 23, 2024. Crab spiders are ambush predators and wait patiently for their prey to approach. (Photo by Robin Loznak/ZUMA Press Wire/Rex Features/Shutterstock)

Veteran cholita wrestler Jennifer dos Caras, 45, holds a cement block over teen wrestler Lucero la Bonita in the ring in El Alto, Bolivia, Monday, January 21, 2019. Trainees of cholita wrestling are still a year away from their full professional debuts while competing in matches against established athletes. (Photo by Juan Karita/AP Photo)

A girl carries on her head a pile of dried shrubs she gathered for cooking and heating, in Kabul, Afghanistan November 18, 2015. (Photo by Omar Sobhani/Reuters)

Sеxy brunet striptease dancer dancing lap dance in front of man. (Photo by Blue SkyImages/Getty Images)