Narrative:

As the aircraft was being towed out, the two bar broke, the aircraft and tow tractor basically did a jack-knife maneuver with the tractor swinging around and ending up underneath the aircraft. The aircraft sustained damage to the nose gear tow attach fittings, the belly sheet metal, a drain mast, and the anticollision light.

Google
 

Original NASA ASRS Text

Title: TOWBAR BROKE ON PUSHBACK RESULTING IN DAMAGE TO THE ACFT.

Narrative: AS THE ACFT WAS BEING TOWED OUT, THE TWO BAR BROKE, THE ACFT AND TOW TRACTOR BASICALLY DID A JACK-KNIFE MANEUVER WITH THE TRACTOR SWINGING AROUND AND ENDING UP UNDERNEATH THE ACFT. THE ACFT SUSTAINED DAMAGE TO THE NOSE GEAR TOW ATTACH FITTINGS, THE BELLY SHEET METAL, A DRAIN MAST, AND THE ANTICOLLISION LIGHT.

Data retrieved from NASA's ASRS site as of August 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.