AVALON, Texas - Officials say two helicopter pilots have escaped injury in an emergency landing in a Central Texas field that left the aircraft on its side.

Lynn Lunsford with the Federal Aviation Administration says the helicopter apparently had a tail rotor problem Tuesday morning. Lunsford says the chopper suffered substantial damage in the accident.

A spokeswoman with Bell Helicopter Textron says the incident happened near Avalon, about 40 miles south of Dallas. Susan Gordon declined to say whether the Bell 214ST was on a test flight. Gordon says such helicopters typically take off and land at the company's facility in nearby Arlington.

She says the two pilots were the only people on board.

Gordon declined to release further information on the crew or speculate on what prompted the emergency landing.