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 girl floats in a bucket in the village of Ologa in the western state of Zulia October 23, 2014. This year the Catatumbo Lightning was approved for inclusion in the 2015 edition of Guinness World Records, dethroning the Congolese town of Kifuka as the place with the world's most lightning bolts per square kilometer each year at 250. Scientists think the Catatumbo, named for a river that runs into the lake, is normal lightning that just happens to occur far more than anywhere else, due to local topography and wind patterns. (Photo by Jorge Silva/Reuters)

The World Bodypainting Festival held from July 4 to 6 at Lake Worthersee in Austria's southern Carinthia province included artists from around the world, drawing visitors to the “Mecca of Bodypainting”, according to the World Bodypainting Association. Photo: World Bodypainting Festival 2014. Photographed July 4th in Poertschach am Woerthersee, Austria July 4, 2014. (Photo by Jan Hetfleisch/Getty Images)

New Jersey based artist, Joe Iurato creates art using hand-cut paper and spray paint to make small wood cutout figures and placed in public spaces. According to Iurato, “a puddle can become a lake, a small crack in a cement wall can become a magnificent climb, a planter box can become a place for a child to play, and a shadow might be a tangible space for a few seconds a day”. Photo: “Small World”. (Photo by Joe Lurato)

In this picture taken on Thursday, December 1, 2016, an Iranian woman covers herself with a blanket due to the cold, while visiting Khour salt lake during her tour of the Mesr desert about 305 miles (500 kilometers) southeast of the capital Tehran, Iran. Deserts make up parts of Iran which have recently become tourist destination for young Iranians looking for a break on their weekend. The increase in tourists to the desert has stimulated economic growth in the area. (Photo by Ebrahim Noroozi/AP Photo)

Descending into the Marum Volcano in Vanuatu, Intrepid explorers found an unusual way of staying warm this winter by spending Christmas day on an active volcano. British climber Chris Horsley, 22, and his friends Gareth Hawken, 30, Geoff Mackley, 50, and Bradley Ambrose, 36, from Auckland, New Zealand, hiked up the Marum Volcano, Vanuatu, on the morning of the 25th. Instead of passing the day with their families, the team climbed down a 1200ft cliff to get close to a flowing lake of lava. (Photo by Bradley Ambrose/Caters News)

An open water swimmer surfaces as she enjoys a socially-distanced dawn swim after breaking the ice on the surface of a lake near Scunthorpe, northern England, January 9, 2021. Faced by a sharp rise in coronavirus infections, driven by the new strain, England entered a strict lockdown on January 5, 2021, with schools and non-essential shops closed for at least six weeks after previous measures failed to halt the steep rise in cases. (Photo by Lindsey Parnaby/AFP Photo)

Ethnic Entha fishermen display placards during a protest against the military coup on Inle Lake, Taunggyi, Myanmar Thursday, February 11, 2021. Large crowds demonstrating against the military takeover in Myanmar again defied a ban on protests Thursday, even after security forces ratcheted up the use of force against them and raided the headquarters of the political party of ousted leader Aung San Suu Kyi a day earlier. (Photo by Aung Ko San/AP Photo)