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)

Natalia Lage Rainha de Drums of the Escola de Samba Inocente de Belford Roxo during a presentation in the parade of the Special Group of Carnival in Rio de Janeiro at Avenida Marques de Sapucai, Sambadrome in Rio de Janeiro on April 21, 2021. The Carnival parades that take place in February were postponed to this month of April due to the high number of cases caused during the pandemic caused by COVID-19 (Coronavirus). (Photo by Thiago Ribeiro/AGIF via AFP Photo)

A South American Coati licks a block of frozen fruits at Israel's Safari Zoo in Ramat Gan, north of the Mediterranean coastal city of Tel Aviv, as temperatures reach 35 degrees Celsius on July 13, 2023. (Photo by Jack Guez/AFP Photo)

Children play among foaming bubbles that form an artwork by Roger Hiorns entitled A Retrospective View of the Pathway, at the Yorkshire Sculpture Park near Wakefield, UK on August 16, 2023. (Photo by James Glossop/The Times)

Photojournalist Evgeniy Maloletka runs from a blaze in a burning wheat field while on assignment after Russian shelling, a few kilometers from the Ukrainian-Russian border in the Kharkiv region, Ukraine, Friday, July 29, 2022. (Photo by Mstyslav Chernov/AP Photo)

Thousands of fireflies dance around Aurora Ghizzi Panizza, age 4, in the grounds of the 15th-century Castello di Torrechiara in Parma, Italy on July 16, 2022. (Photo by Alberto Ghizzi Panizza/Animal News Agency)

In this undated photo provided by the North Korean government, North Korean leader Kim Jong Un tries a weapon during his three-day inspection from Aug. 3 until August 5, 2023 at major munitions factories in North Korea. Independent journalists were not given access to cover the event depicted in this image distributed by the North Korean government. The content of this image is as provided and cannot be independently verified. Korean language watermark on image as provided by source reads: “KCNA” which is the abbreviation for Korean Central News Agency. (Photo by Korean Central News Agency/Korea News Service via AP Photo)

Samir Ayoub, uncle of three Lebanese girls killed along with their grandmother yesterday, by what he says was an Israeli airstrike that targeted their car in which they were traveling between Aytaroun and Aynata, speaks as he mourns them beside the burned car near the Lebanon and Israel border, in the outskirts of the southern town of Aynata, Lebanon on November 6, 2023. (Photo by Zohra Bensemra/Reuters)