A320 IS DAMAGED AFTER PUSHBACK WHEN GND CREW FAILED TO ALERT FLT CREW TO SET BRAKES. ACFT ROLLED OVER TOW BAR AND RIGHT ENG CONTACTED BELT LOADER.

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WE INITIATED THE PUSHBACK PROCESS USING THE CURRENT VERBIAGE. AFTER BEGINNING THE PUSH WE WERE CLRED TO START BOTH ENGS BY THE TUG DRIVER. WE BEGAN THE L ENG START DURING THE PUSH. AS THE L ENG WAS STARTING WE OBSERVED A BELT LOADER WITH SEVERAL BAGS APCHING THE ACFT. THE CAPT ASKED THE TUG DRIVER IF THEY WERE PLANNING TO LOAD LATE BAGS OUT ON THE RAMP AND HE REPLIED THAT THEY WERE. THE CAPT THEN INDICATED THAT WE WOULD NOT START THE R ENG; AND RELAYED THIS INFO TO THE TUG DRIVER. THE TUG DRIVER PUSHED THE ACFT TO THE PROPER SPOT; BUT COCKED OFF SLIGHTLY TO THE SIDE. WE THOUGHT NOTHING OF IT WHEN THE ACFT STARTED MOVING FORWARD; AS WE ASSUMED THE TUG DRIVER WAS REPOSITIONING US; AND IN THE ABSENCE OF ANY FURTHER COM. SHORTLY AFTER MOTION FORWARD WE HEARD AND FELT SEVERAL LOUD JOLTS; AND INDICATED BTWN US THAT IT WAS UNUSUAL; AND WONDERED IF THE TUG DRIVER WOULD DAMAGE THE NOSE GEAR. THE JOLTS SUBSIDED FOR A FEW SECONDS AND THEN RETURNED. AT THAT TIME THE TUG DRIVER TOLD US URGENTLY TO 'SET BRAKES;' AND SIMULTANEOUSLY A RAMP SVC MAN RAN OUT FROM THE R SIDE OF THE ACFT AND GAVE US AN EMER STOP SIGNAL. BOTH OF US HIT THE TOE BRAKES AND THE CAPT SET THE PARKING BRAKE. AS WE FOUND OUT LATER; THE PUSH CREW HAD DISCONNECTED THE TOW BAR AND STARTED BACKING THE TUG WITHOUT GIVING US THE COMMAND TO SET THE BRAKES. AS THE TUG BACKED; THE ACFT FOLLOWED IT DUE TO L ENG IDLE THRUST. THE NOSE GEAR ROLLED OVER THE TOW BAR AND THE R ENG COWL CONTACTED THE BELT LOADER WHICH HAD BEEN POSITIONED TO THE FORWARD CARGO BIN. LUCKILY; THERE WERE NO INJURIES. DURING A SHORT DEBRIEF; THE TUG DRIVER INDICATED THAT HE HAD FORGOTTEN TO GIVE THE SIGNAL TO SET THE BRAKES. I AM NOT SURE IF PUSHBACK TRAINING INCLUDES GUIDANCE TO XCHK THE PARKING BRAKE ON THE NOSE GEAR.