Three American cops are lucky to be alive after an airborne truck flew in between their patrol cars at the side of a busy motorway.

The Iowa police officers were attending an incident on Interstate 80 and were parked around 20 metres apart on the side of the road when a truck was rear-ended and sent skyward.

Just seconds before the truck took flight, one of the officers can be seen walking between the two parked response vehicles in the exact same place the truck flies through.

Recorded on one of the police car's dash cams, the film shows the vehicle careering through the narrow gap. The slow motion footage at the end of the clip shows just how lucky the police officers are to be alive.

The driver of the truck, 45-year-old Dana Miller, and his passenger, were unharmed in the incident.

He later told KWQC-TV: "I heard a crunch, and suddenly I was flying through the air. It all happened so fast. I didn't know what was happening until I was in the ditch."

Johnson County Sheriff Lonny Pulkrabek told the news channel that this was a stark reminder to distracted drivers to stay focused on the road.

"This is a glaring example of how close we came to losing three troopers all because a driver chose not to slow down when approaching a crash scene full of vehicles and emergency lights."

Watch the lucky escape below...