Iowa's congressional delegation wants answers from the Air Force on recommendations to retire 21 F-16s fighter jets from an Iowa Air National Guard unit in Des Moines.

The Air Force has proposed replacing the F-16s at the 132nd Fighter Wing with unmanned drones. The Air Force also recommends reducing the number of tankers at the 185th Air Refueling Wing in Sioux City.

The proposals are part of a plan to cut $487 billion from the defense budget over 10 years.

The Iowa delegation met Thursday with Air Force Secretary Michael Donley and other leaders.

Republican Senator Charles Grassley says it's up to Congress to approve the plan and National Guard advocates are signaling they "won't go quietly." Democratic Senator Tom Harkin vows to do everything to keep the 132nd flying.