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 battleship USS Iowa fires its 16-inch guns during duty in the Persian Gulf on December 16, 1987. In 1943, the Iowa ferried President Franklin Roosevelt home from the Teheran Conference, where post-WW II leaders divided up the world. The ship fought battles from the South Pacific to Korea and escorted convoys through the Persian Gulf. Forty-seven sailors died atop its deck when an explosion ripped through a gun turret. Now, the new port for the retired USS Iowa just might be the home of California's annual asparagus festival, the gritty agriculture port town of Stockton on the San Joaquin River, about 80 miles inland from San Francisco. (Photo by Eric Risberg/AP Photo)

A waste picker unloads garbage at a waste transfer station in Bamako, Mali, August 19, 2018. In the Malian capital of Bamako, donkey carts driven by young men like 19-year-old Arouna Diabate play a vital role battling the fast-growing city's waste problem. Every morning before dawn, Diabate hitches his donkey to a cart and sets off on his rounds, going door-to-door to collect household garbage which he delivers to a local waste transfer station for a monthly salary of around $35. “I won't be picking up trash with a donkey cart for the rest of my life, but for now people appreciate us because we help clean up the homes of Bamako”, Diabate said. (Photo by Luc Gnago/Reuters)

South Korean performers participate in a re-enactment of the battle of the Korean war during the ceremony to mark the 70th anniversary of the Korean War in Cheorwon, near the border with North Korea on June 25, 2020 in Cheorwon, South Korea. Over 66,000 South Koreans have been separated from their families during the Korean War which started on June 25, 1950, and effectively split the Korean Peninsula into two over the 3-year conflict. (Photo by Chung Sung-Jun/Getty Images)

A man cries in a graveyard during the funeral of Nasser Ali Afglio, a young Libyan rebel killed during battle with government troops loyal to Libyan ruler Moammar Gaddafi April 19, 2011 in Misrata, Libya. The graveyard where Nasser was buried has hundreds of simple concrete graves; many dozens are those that have been killed during the last two months of fighting in the besieged town. Thousands of civilians are trapped in Misrata as fighting continues between Libyan government forces that have surrounded the city and anti-government rebels there. (Photo by Chris Hondros/Getty Images)

A fisherman caught a record-breaking 805lb Mako shark – and then barbecued and ate it with his friends. Joey Polk, 29, and his two cousins Earnie Polk, 43, and Kenny Peterson, 21, battled the 11ft predator for more than an hour before finally hauling it onto the beach. They normally tag and release their catches for conservation but were unable to resuscitate this one and instead made it the main course at a jumbo-sized family barbecue. (Photo by Joey Polk/Barcroft Media)

People march past the Colosseum during the Gay Pride parade in Rome, Saturday, June 11, 2016. Italy joined the rest of Europe last month in giving some legal rights to gay couples after a years-long battle and opposition from the Catholic Church to anything that smacked of authorizing gay marriage. (Photo by Fabio Frustaci/AP Photo)

A pet horse tethered on land known as “The Cracker” in Tipton that may be seized by bailiffs on October 10, 2011 in Dudley, England. Horse lovers in Tipton are battling the local council over the tradition of keeping their horses tethered on public land near their homes. Locals say tradition that has been in existence for generations and believe it stems from the age of the canal when many local men used their horses to tow canal barges along the industrial Black Country canals. After a spate of horses running free Sandwell Council are now enforcing the law and impounding tethered horses. Locals are planning their next protest with a horse drive to the council headquarters to try and save their traditions. (Photo by Christopher Furlong/Getty Images)