UPDATED 06/14/11 6:02 p.m.

OSWEGO, Ill. (CBS) — Federal investigators are starting to remove the charred remains of the vintage plane that crashed in Oswego.

The B-17 plane known as the Liberty Belle landed in a farm field near the intersection of Route 71 and Minkler Road, after an engine fire. The plane was destroyed by the flames after the landing, but all seven crew members escaped with only one suffering a minor injury.

Kevin Potts, a farmer in the area, said he saw the plane fly over. He told CBS 2 that the plane was obviously in trouble, as it was flying low and there was fire in one of the engines.

“I noticed that it was a little too low and was kind of coming down, and then I noticed flames coming out underneath its left wing,” Potts told CBS 2 on Monday.

Meanwhile, an audio recording has been released from the Aurora air traffic control tower, documenting the conversation between the tower and the pilot. CBS 2’s Derrick Blakley reports.

“We’re on fire! We’re on fire! We’re on fire! We’re on fire!” the pilot is heard saying.

“Who’s on fire?” an air traffic controller says.

“Put it on the ground! Put it on the ground! Put it on the ground!” the pilot says frantically.

The plane landed with a fiery blast and a plume of black smoke.

The plane dated from 1944, and was part of the Liberty Foundation’s 2011 Salute to Veterans at the Aurora Municipal Airport.

The National Transportation Safety Board is now investigating the cause of the mishap, but says an official determination could take as long as a year.

Watch & Listen LIVE