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INSIGHTi
Afghan Aerial Evacuation in Context
August 24, 2021
On August 15, 2021, the U.S. military began evacuating thousands of persons from Hamid Karzai
International Airport, in Kabul, Afghanistan. As of August 24, the military has airlifted approximately
64,000 persons since July (Figure 1)—of those, approximately 40,000 were reportedly evacuated since
August 16 and 12,700 were reportedly evacuated on August 23 alone. President Biden 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.
Figure 1. Stated Passenger Evacuations and Flights, by Day
Source: CRS analysis of DOD press briefing transcripts August 17-24.
Both military and civilian aircraft are being used for the evacuation. General Mark Mil ey, Chairman of
the Joint Chiefs of Staff, stated on August 18 that the U.S. military was flying on average 20 C-17 flights
every 24 hours, with the ability to expand capacity. On August 22, U.S. and al ies performed 94 flights
from Kabul. On the same day, Secretary of Defense Lloyd Austin activated the Civil Reserve Air Fleet
(CRAF), leveraging 18 aircraft from six airlines to augment Air Force capacity. This is the third time the
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CRAF has been activated. The other times were in 1990-1991, supporting Operation Desert Shield/Storm,
and 2002-2003, supporting Operation Iraqi Freedom. The Department of Defense (DOD) has stated
military aircraft wil fly from Kabul to the several processing centers, then the CRAF wil fly evacuees
from these centers to the United States.
There are several constraints affecting air operations for the Kabul airlift. First, Kabul Airport has a single
runway and a relatively smal parking area for aircraft, physical y 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
processing visas in Qatar, Bahrain, and the United Arab Emirates; the Department of Defense announced
that a fourth location would start in Germany. Final y, 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.
Figure 2. U.S. C-17 Aircraft
Source: https://media.defense.gov/2008/Jan/11/2000414240/-1/-1/0/080103-F-2034C-908.JPG.
Historical Civilian Evacuations: Scope of Operations
In 1975 the U.S. military executed Operation Frequent Wind, which evacuated U.S. and South
Vietnamese persons primarily from Saigon. During the operation, 57,507 persons were transported by
U.S. aircraft. From April 1 to April 29, 1975 (28 days total), the U.S. Air Force flew 201 C-141 flights
and 174 C-130 flights (for a total of 375 flights) to evacuate 50,493 U.S. and Vietnamese citizens; an
additional 7,014 persons were airlifted by helicopters.
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The largest civilian aerial evacuation in history was the Indian repatriation of 176,000 civilians from
Kuwait between August and October 1990, precipitated by the Iraqi invasion of Kuwait. Over the course
of approximately 59 or 63 days (depending on sources), the Indian Air Force and commercial airline Air
India operated 488 flights to repatriate civilians. According to media reports, many Indians were not
immediately ready to leave the country.
In both instances, the United States and India required at least a month to transport approximately 57,000
and 176,000 persons, respectively. DOD is currently planning to transport approximately 100,000 persons
by August 31, some of whom are not necessarily located in Kabul.
Historical Airlift Capacity
On June 19, 1948, the Soviet Union blocked al trains and vehicles from entering Berlin. The United
States and its al ies decided to utilize cargo aircraft to bring food and supplies into the city from June 24,
1948 through May 12, 1949. During this period, the U.S. Air Force tasked al C-54 aircraft to provide
airlift. By the end of operations, the United States and its al ies had flown 277,000 flights departing from
four primary fields (an average of 860 flights per day, or 35.8 flights per hour) and landing at two airports.
On August 22, U.S. and al ied aircraft flew 61 flights from Kabul’s single runway.
According to technical specifications, a C-54 has a stated cargo payload of 28,000 pounds; a C-17 by
comparison has a payload of 170,900 pounds. Thus a single C-17 has the carrying capacity of 6.1 C-54s.
At the height of the Berlin airlift, it was reported that U.S. and al ied forces were able to move 8,000 tons
of cargo, requiring approximately 94 C-17s if they were utilized today. As a result, the current stated
airlift capacity flying into Kabul represents approximately 33% of the airlift capacity, with additional
airlift being provided by other U.S. cargo aircraft along with al ies and commercial aircraft (potential y
exceeding airlift capacity from Berlin in the 1940s). This does not account for capacity constraints
outlined above.
Potential Questions for Congress
President Biden stated that al U.S. forces would withdraw from Afghanistan by August
31. Given recent developments, how many Afghan civilians and American citizens wil
be transported before then?
U.S. evacuation efforts are centralized in Kabul; however, many evacuees are reportedly
not located in the city itself. What plans do the State Department, the White House, and
DOD have to evacuate both U.S. and Afghan civilians dispersed across Afghanistan,
potential y in hostile environments?
Based on open source reporting, DOD has tasked significant portions of the C-17 fleet to
support the evacuation at Kabul Airport. Does DOD have sufficient cargo lift capacity to
continue these evacuation efforts if another national security contingency were to occur?
Relatedly, would DOD’s ability to execute worldwide operational plans be limited
because of its tasking of such a significant amount of strategic mobility assets?
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Author Information
John R. Hoehn
Jeremiah Gertler
Analyst in Military Capabilities and Programs
Specialist in Military Aviation
Disclaimer
This document was prepared by the Congressional Research Service (CRS). CRS serves as nonpartisan shared staff
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