- War in Afghanistan (2001-present)
image sourceGetty Imagesimage captionThe aircraft is designed to carry paratroopers, armoured vehicles, and even tanks
On 15 August, as the Taliban entered the Afghan capital, Kabul, a US Air Force plane safely evacuated 823 Afghan citizens – including 183 children.
The number was a record for the Boeing C-17 Globemaster III – the four-engined transport plane that has been at the centre of the airlift from Hamid Karzai International Airport.
Developed in the 1980s and first flown in the 1990s, it is now used by countries around the world to shuttle troops, cargo and sometimes people in danger.
One Afghan woman even gave birth to a baby girl on a C-17 on Sunday. She went into labour as the flight was en route to Ramstein Air Base in Germany, and medical personnel helped deliver the child in the plane's cargo hold once it had landed.
image sourceEPAimage captionThe rear of the plane opens up to allow people and cargo to boardimage captionAfghans in their thousands have boarded C-17 flights in the past week
According to the US Air Force fact sheet about the plane, it is designed to carry up to 77,519kg (170,900lb) worth of cargo.
Armoured vehicles, lorries and even the M1 Abrams battle tank can all go aboard the craft.
The crew of three – two pilots and a loadmaster – fill up the plane via a cargo ramp at the rear.
It has a range of 2,400 nautical miles (2,762 miles; 4,445km), and measures 53 metres (174ft) long, with a wingspan of 51.75 metres (169ft 10in).
image sourceGetty Imagesimage captionThe first C-17 flight took place in 1991image sourceGetty Imagesimage captionThe C-17 can drop 102 paratroopers "with their accompanying equipment"image sourceGetty Imagesimage captionThe planes have been used all around the world
In a briefing on Saturday, the US Department of Defense said 17,000 people had been flown out of Kabul airport so far, including some 2,500 US citizens.
Officials are trying to step up the evacuations. A Pentagon statement on Sunday said the government would use 18 commercial aircraft to help transport people out of the country.