Chatter over the airwaves has provided some clues about what happened in Arizona. A chief flight instructor who was in the air with a student that day heard the commotion over the radio: One plane was attempting a touch-and-go when another clipped its propeller while attempting to land.

At least two people have died after two small single-engine planes collided midair Wednesday morning at an Arizona airport, officials said.

A midair collision involving two small planes in southern Arizona killed two people Wednesday morning, authorities said. Federal air-safety investigators said each plane had two people aboard when they collided at Marana Regional Airport on the outskirts of Tucson.

Tens of thousands of planes take off, land and perform touch-and-goes at the Marana Regional Airport in southern Arizona every year. Without an air traffic control tower, it's a calculated dance that requires communication by pilots.