Victoria's Secret angels Adriana Lima, Candice Swanepoel, Alessandra Ambrosio and Miranda Kerr arrive at the 2011 Victoria's Secret SWIM Collection Pink Carpet Event hosted by VS Angels at Club L on March 30, 2011 in Los Angeles, California. (Photo by Jerod Harris/Getty Images for Victoria's Secret)

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)

Tech. Sgt. Milo Hinson, 3rd Combat Camera Squadron, uses a flashlight while shooting a Berretta 9mm during the night-fire portion of Advance Weapons, Tactics and Techniques training in San Antonio. During night-fire training, airmen learn how to tactically illuminate targets with flashlights and practice using night vision goggles. (Photo by Staff Sgt. Jonathan Snyder/U.S. Air Force). 2011

Caroline Wozniacki of Denmark serves to Alisa Kleybanova of Russia during the BNP Paribas Open at the Indian Wells Tennis Garden on March 15, 2011 in Indian Wells, California. (Photo by Matthew Stockman/Getty Images)

Ali Carter of England looks on during the match against Stuart Bingham of England during the 2011 China Open at Beijing University Students Gymnasium on March 30, 2011 in Beijing, China.

A model showcases designs on the catwalk during Beijing Institute of Fashion Technology and Taiwan Shin Chien University Graduates Collection show of China Fashion Week A/W 2011 on March 25, 2011 in Beijing, China. (Photo by Feng Li/Getty Images)

Dayang Nur Atikah, poses as she is announced as the winner of the Supermodel of the World Malaysia 2011 at Sepang International Circuit on April 10, 2011 in Kuala Lumpur, Malaysia. Dayang Nur Atikah, 18, will represent Malaysia at the 30th anniversary of the Ford Models Search in New York. (Photo by Syamsul Bahri Muhammad/Getty Images)