A team of experienced skydivers recently dropped in to help at a plane crash they happened to witness in Wisconsin – and used their training as paramedics to treat a seriously injured victim before ground-based rescue crews arrived.

The single-engine plane carrying four people crashed in a cornfield near East Troy on Sunday, watched by the occupants of a Skydive Milwaukee aircraft who were preparing for an afternoon of recreational jumping.

“He kind of banked up and then he disappeared behind the trees, and we were all waiting for him to show back up,” John Bechtel, one of several veteran skydivers on board, told Wisconsin ABC News affiliate WISN.

“We all looked at each other and said, ‘Did we just see a plane crash?’”

Bechtel, who has more than 30 years of skydiving experience, said he and two colleagues decided to jump straight to the site of the crash after calling in what they saw to authorities on the ground.

One of the jumpers, who like Bechtel is also a former paramedic, helped a woman with a serious head injury until an EMT crew arrived by ambulance.

“The timing couldn’t have been any better. Had we left five minutes earlier, we wouldn’t have seen it. If we left 15 minutes later, we wouldn’t have been able to get there to assist,” Bechtel said. “I’m just glad that we were able to do what we could and get in and help.”

Officials in Walworth county said three passengers in the crashed plane were taken to hospital and the fourth was treated at the scene. All are expected to survive.

Aerial footage on the WISN website showed the aircraft, a Beechcraft 35-A33 Debonair manufactured in 1961, upright on the ground with one of its wings detached.

Jonah Johnston, the pilot of the jump plane, told air traffic controllers in an emergency call: “I have a plane crash, just south of East Troy. He’s in a field. I can drop a load of skydivers right over them to potentially help aid.”

Kevin Flynn, another of the skydivers, told Milwaukee news outlet WDJT that he and Bechtel started calling out as soon as they hit the ground because they couldn’t see the plane through the tall corn.

“I got in there and started doing the Marco Polo game to get a response,” he said. “People started yelling at me so I could dial in where I was going.

“It could’ve been a lot worse for those poor people in that crash, no fatalities. I know it’s a terrible thing to happen, but I think it’s a wonderful outcome.”

In a statement, Skydive Milwaukee said: “A few members of our skydiving community who are trained [emergency medical technicians] were already airborne in our jump plane and jumped out to assist at the scene, which was difficult to access from the road.

“We’re grateful they were able to help when they were needed.”

The identities of the victims have not been released. The National Transportation Safety Board (NTSB) opened an inquiry into the cause of the crash and an investigator arrived at the site on Sunday afternoon.