The Defense Department plans to provide 20 Boeing CH-47 Chinook helicopters to Afghanistan’s security forces in a bid to save on support costs and air crew requirements, Pentagon officials said in a briefing that provides new details on the program.

The U.S. military is reducing the number of UH-60 Black Hawks it plans to provide Afghan forces from 159 to just 53 — a two-thirds cut in the quantity of rotary wing assets American forces had intended to provide, according to a Defense Department report.