To fight ISIS. Per CNN:
A pair of nearly 50-year-old planes has been brought out of retirement to fight ISIS.
The Vietnam-era OV-10 Bronco turbo-propeller planes are part of an experiment to see if “light turbo-prop aircraft” are more effective in conducting counterinsurgency operations, a U.S. military representative told CNN this week.
During their deployment, the planes flew 120 combat missions against ISIS targets as part of the counter-ISIS coalition, said spokesman Capt. Bryant Davis of U.S. Central Command, which oversees military operations in the Middle East.
The last US military operator of the OV-10 had been the Marine Corp in 1995. You can see a photo of a OV-10 here.