A young woman employee of North American Aviation Incorporated, working over the landing gear mechanism of a P-51 fighter plane, Inglewood, California, 1942. (Photo by Alfred T. Palmer/Buyenlarge/Getty Images)

British Supermodel Kate Moss during a fashion shoot for “You” magazine at a photo studio in 1995 in New York City, New York. (Photo by Catherine McGann/Getty Images)

Romanian singing duo Gabriella and Monica Irimia, The Cheeky Girls prforms in Falkirk, Scotland on May 4, 2003. (Photo by Michael Schofield/News Group Newspapers Ltd)

A woman sits as she gets a tattoo on her leg during the annual Panama City Ink Fest in Panama City August 16, 2015. (Photo by Carlos Jasso/Reuters)

In this March 18, 2015 photo, Andrea, better known as Loira, which is the Portuguese word for “blonde”, poses for a portrait in an open-air crack cocaine market, known as a “cracolandia” or crackland where users can buy crack, and smoke it in plain sight, day or night, in Rio de Janeiro, Brazil. Andrea says she is married and has a home, but she keeps returning to crackland to feed her addiction. (Photo by Felipe Dana/AP Photo)

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)

Mikhail Kalashnikov, the father of the world's most popular assault rifle, is handed an AK-74 November 23, 2002 in Izhevsk,1000 East km. from Moscow. November 23 marked the 55th anniversary of the release of the first Kalashnikov gun. According to the Moscow-based Center for Analysis of Strategic and Technologies some 70 million to 100 million Kalashnikovs have been built worldwide since 1947, compared about 7 million to Kalashnikov's Western rival the M-16 assault rifles. (Photo by Oleg Nikishin/Getty Images)

Stuart Craig of Washington tries out a Sig Sauer 1911 model Scorpion pistol at the Sig Sauer booth at the National Shooting Sports Foundation's 34th annual Shooting, Hunting, Outdoor Trade (SHOT) Show at the Sands Expo and Convention Center January 17, 2012 in Las Vegas, Nevada. The SHOT Show is the largest annual gathering of shooting professionals with more than 1,600 exhibitors and 30,000 attendees expected. (Photo by Ethan Miller/Getty Images)