MLG PUSHED BACK; BLOCKING SECOND ACFT. GND CREW DISCONNECTS AND LEAVES FLC WITHOUT COM. TOWING BACK TO AATE TUG JACKKNIFED; WENT UNDER ACFT CAUSING STRUCTURAL DAMAGE.

Narrative

PUSHED BACK OP. ACFT THAT HAD PREVIOUSLY PUSHED WAS BEHIND AND OFFSET TO R IN ALLEY. GND CREW PUSHED ACFT BACK WITH HEADSET OPERATOR ON FORWARD R SIDE OF ACFT. RESULTING PUSH BLOCKED OTHER ACFT FROM EXITING ALLEY. GND CREW DECIDED TO PULL BACK TO GATE BUT JACKKNIFED TUG. I ATTEMPTED TO CONTACT GND CREW TO NO AVAIL. GND CREW ATTEMPTED TO PULL MY ACFT AROUND BLOCKED ACFT; WITH MARGINAL WINGTIP CLRNC. COULD NOT COM WITH GND CREW. TUG AGAIN JACKKNIFED AND WENT UNDER ACFT; CAUSING STRUCTURAL DAMAGE. SET BRAKES AND SHUT DOWN ACFT. (#1 ENG WAS STARTED ON INITIAL PUSHBACK AND CONTINUED TO RUN AT IDLE THROUGH THE INCIDENT). FOUND OUT LATER THAT HEADSET PERSON HAD DISCONNECTED PRIOR TO FIRST JACKKNIFE TO CHK WINGTIP CLRNC. IT APPEARS THAT I WAS OUT OF CONTACT WITH GND CREW; UNKNOWN TO ME THROUGHOUT THE INCIDENT; WHICH EXPLAINS WHY I COULDN'T GET THEM TO STOP. ALSO FOUND OUT ACFT WAS DISCONNECTED FROM TUG AND RECONNECTED AFTER FIRST JACKKNIFE. ALSO THAT ACFT EVENTUALLY CAUSED TOWBAR TO SNAP AND KEPT ROLLING TOWARDS TUG. ALL UNKNOWN TO ME.