From the Document: "August 24, 2021 On August 15, 2021, the U.S. military [hyperlink] began evacuating thousands of persons from Hamid Karzai International Airport, in Kabul, Afghanistan. As of August 24, the military has airlifted approximately 64,000 [hyperlink] persons since July --of those, approximately 40,000 were reportedly evacuated since August 16 and 12,700 were reportedly evacuated [hyperlink] on August 23 alone. President Biden [hyperlink] has stated that he intends to complete the evacuation and the Taliban have stipulated that U.S. forces need to withdraw from Afghanistan by August 31. [...] There are several constraints affecting air operations for the Kabul airlift. First, Kabul Airport has a single runway and a relatively small parking area for aircraft [hyperlink], physically limiting the number of aircraft. Second, there is a limited amount of fuel at the airfield, and DOD has instructed aircraft not to refuel on the ground. Third, airlift operations are dependent on the number of State Department consular officers [hyperlink] processing visas[.] [...] Finally, the 85,000 evacuee estimate accounts for U.S. and Afghan civilians across the entire country (which is the size of Texas). It is unclear how many people outside of Kabul are being evacuated given limited infrastructure in the country and the lack of security outside of the airport. Despite these constraints, it may be instructive to consider previous airlifts from emergency situations."
CRS Insight, IN11730
Congressional Research Service: https://crsreports.congress.gov/