The U.S. Air Force will try to spend its way out of a combat stress crisis by offering drone pilots annual bonuses if they sign a five-year contract to fly the unmanned aerial vehicles. Air Force Secretary Deborah Lee James is scheduled to announce a plan publicly Wednesday after months of reports that experienced drone pilots are choosing to walk away from the program rather than re-enlist.

James will announce a program to assign roughly 80 Air Force pilots graduating from flight school automatically into the drone program for a year, the Wall Street Journal reported. When the pilots' initial commitment expires he or she will then be asked to sign a five- or nine-year contract providing for $15,000 in bonuses every year and the option to take half the money upfront.

As the Air Force faces increased demand for drone missions -- with activity in Yemen, Pakistan, Iraq, Syria and elsewhere -- pilots have become increasingly stressed. They complain of flying 900 combat missions a year, when traditional Air Force pilots fly closer to 250, with little chance of promotion or academic advancement.

Last month Sen. Claire McCaskill, D-Mo., wrote a letter to the Air Force saying a drone pilot “could be sitting down to a meal with his or her family less than two hours after killing Islamic State or Taliban fighters on the other side of the world. They would be playing with their children shortly after witnessing up close and in graphic detail the effects of a 500-bomb or Hellfire missile on a soft target.”

The Air Force announced in June the 65 daily missions it currently flies from a base in the Nevada desert will drop to 60 flights. The Air Force also plans to invest an additional $100 million in drone video surveillance capabilities.