Pro-Russian separatists from the Chechen “Death” battalion take part in a training exercise in the territory controlled by the self-proclaimed Donetsk People's Republic, eastern Ukraine, December 8, 2014. Chanting “Allahu Akbar” (God is greatest), dozens of armed men in camouflage uniforms from Russia's republic of Chechnya train in snow in a camp in the rebel-held east Ukraine. They say their “Death” unit fighting Ukrainian forces has 300 people, mostly former state security troops in the mainly-Muslim region where Moscow waged two wars against Islamic insurgents and which is now run by a Kremlin-backed strongman. (Photo by Maxim Shemetov/Reuters)

An injured NATO soldier lies on the ground following a suicide car bomb attack that targeted foreign military vehicles in the Afghan capital Kabul on June 30,2015. A powerful blast hit downtown Kabul on June 30 as a suicide car bomber targeted foreign military vehicles, officials said, with casualties feared. The blast came on the main road to the airport, around 500 meters (550 yards) from the US embassy and near a base for foreign troops.“It was a suicide car bomber targeting a convoy of foreign forces in Kabul”, interior ministry spokesman Sediq Sediq said. (Photo by Wakil Kohsar/AFP 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)

During a jungle survival program February 20, 2013 taught by Royal Thai Special Forces in Sannapit, Thailand, U.S. Marines learned to catch cobras and drink their fresh blood, not to mention eat forest insects and pull the heads off of chicken. The training was part of Operation Cobra Gold 13, the 32nd edition of international military exercises hosted by the Thai. According to a U.S. Marines press release, Cobra Gold is the largest exercise of its kind in Asia and incorporates troops from five other nations in addition to the U.S. and Thailand. The Daily Mail reports that the Marines were invited to experience the local custom of drinking cobra blood after being taught to catch and kill cobras in the wild. As CNN notes, Cobra blood is believed to be a panacea and aphrodiasic in parts of Southeast Asia. In Jakarta, vendors can earn over $100 a night selling shots of cobra blood mixed with liquor. (Photo by Pornchai Kittiwongsakul/AFP Photo)

A Polisario fighter sits on a rock at a forward base on the outskirts of Tifariti, Western Sahara, September 9, 2016. At a rocky outpost in Western Sahara, a new generation of soldiers who have never known war are mobilising as tensions resurface in one of Africa's oldest disputes after a quarter century of uneasy peace. (Photo by Zohra Bensemra/Reuters)

A Palestinian woman paints a mural, depicting a masked Palestinian holding a knife, in support of Palestinians committing stabbing attacks against Israelis, in Rafah in the southern Gaza Strip November 3, 2015. (Photo by Ibraheem Abu Mustafa/Reuters)

Maj. Matt O'Donnell of Glenelg, MD shields himself from rotor wash as Ospreys carrying the delegation of U.S. Secretary of Defense Leon Panetta leaves on March 14, 2012 at Forward Operating Base Shukvani, Afghanistan. Panetta is also scheduled to meet with President Karzai during his two-day visit to Afghanistan. The trip comes as the Taliban has vowed revenge following this past weekend's killing spree by a U.S. soldier who is accused of killing 16 civilians in Afghanistan. Most of those killed were children and women. (Photo by Scott Olson/Getty Images)

A woman poses for a photo in front of the Wagner Group military vehicle on June 24, 2023 in Rostov-on-Don, Russia. (Photo by Feodor Larin/Anadolu Agency via Getty Images)