PRIOR TO TAXI; LACK OF COORD BTWN FLC AND GND TUG DRIVER; RESULTED IN ACFT HITTING TOW BAR AND DEFLATING NOSE TIRES.

Narrative

FLT PUSHED BACK FROM GATE AT MCO USING NEW ICAO PROCS. DURING PUSH; GND CREW MAN CLRED THE FLT TO START ENGS; #2 ENG WAS STARTED; THE BRAKES WERE SET AND GND CREW ADVISED 'TOW BAR DISCONNECTED; STANDING BY TO DISCONNECT.' THE COCKPIT REPLY WAS 'STAND BY -- UNTIL BOTH ENGS ARE STARTED.' AFTER #1 ENG WAS STARTED; THE CHKLIST WAS COMPLETED AND THE FO CALLED FOR TAXI CLRNC. TAXI CLRNC WAS RECEIVED TO RWY 36R AND TAXI PWR WAS APPLIED. A SCRAPING NOISE WAS HEARD/FELT AND THE BRAKES WERE APPLIED; BRINGING THE ACFT TO A STOP. THE NOSE TIRES HAD RUN OVER THE TOW BAR; DEFLATING THE R NOSE TIRE AND CUTTING THE L TIRE. AFTER SHUTTING THE ENGS DOWN; THE ACFT WAS TOWED BACK TO THE GATE. THE ACFT WAS INSPECTED WITH BOTH NOSE TIRES BEING CHANGED AND NO DAMAGE TO THE ACFT DETECTED. THE GND CREW MAN WAS NOT TOLD TO 'DISCONNECT' AND THE THUMBS UP SIGNAL HAD NOT BEEN EXCHANGED. FAILURE TO RECEIVE A THUMBS UP PRIOR TO TAXI CAUSED THE INCIDENT. UNDER OUR PROC PRIOR TO THE NEW ICAO; THE GND CREW DISCONNECTED AS SOON AS PUSHBACK WAS COMPLETE AND I BELIEVE THAT THE GND COM USING 'DISCONNECT' TWICE INFLUENCED MY FAILURE TO REALIZE THAT FORMAL SENDOFF PROCS WERE BYPASSED. ADDITIONALLY; A SINGLE MAN PUSHBACK WAS UTILIZED BUT NOT COMMUNICATED TO THE FLT STATION. THIS RESULTED IN THE TOW BAR BEING DISCONNECTED BUT STILL IN THE PATH OF THE ACFT SINCE THE HEADSET MAN WAS ALSO THE TUG DRIVER.