The most commonly cited figure is 73 aircraft left behind during the Afghan withdrawal, according to BBC reporting. That same report notes most of the Afghan air force’s aircraft were later thought to be in Taliban hands, but the exact total used in the evacuation itself is not pinned to one simple number.

If you mean the evacuation flights into and out of Kabul, the answer is harder to state as a single count because the operation used many military transports over several days, including C-17s, and officials described the airlift in phases rather than as one fixed aircraft total.

Quick distinction

  • Left behind in Afghanistan: 73 aircraft.
  • Used in the evacuation airlift: not given as one universally agreed single number in the sources I found, because it depended on how you count aircraft, sorties, and phases of the operation.

TL;DR: If you’re asking about aircraft associated with the withdrawal overall, 73 planes is the best-cited headline number; if you mean the evacuation flights, there isn’t one clean public count in the sources above.