South Dakota National Guard helicopter pilots are partnering with state wildland firefighters to conduct aerial water delivery training. The annual practice serves as a refresher training for both National Guard Black Hawk pilots and state wildland firefighter ground personnel. Helicopters are used to gather 500 gallons of water at a time to drop on a simulated wildland fire. The training is Friday, April 26 near the Angostura Reservoir in the Black Hills. Use of drones in the area during training is prohibited.