B767 CREW HAD ACFT ROLL INTO HE JETWAY AFTER NOT GETTING THE PARKING BRAKES SET PROPERLY.

Narrative

WE TAXIED IN TO GATE AT SEA UNDER THE DIRECTION OF A GUIDE MAN. WE WERE GIVEN A NORMAL STOP SIGNAL WHERE I WOULD EXPECT TO STOP; SET THE PARKING BRAKE AND SHUT DOWN. I KNOW I STOPPED THE PLANE AND AM CERTAIN I PULLED THE PARKING BRAKE HANDLE. I SAW THE GUIDE MAN LOWER HIS HANDS AND WALK OFF AS IF ALL WAS NORMAL. I SAW THE APU WAS UP TO SPD AND TOLD THE FO TO SHUT DOWN BOTH ENGINES. WITHIN SECONDS OF SHUTTING DOWN THE ENGS; WE HEARD A 'KA-CHUNK' SOUND. I INSTINCTIVELY LOOKED OUT TO SEE IF THE PLANE WAS MOVING. NOT SEEING ANY MOVEMENT OUTSIDE; I LOOKED BACK INSIDE AT THE PARKING BRAKE HANDLE AND WAS SURPRISED TO SEE IT WAS NOT SET. I RESET THE PARKING BRAKE; BUT THE L ENG UPPER COWL HAD CONTACTED THE JETWAY AND PUT A SUBSTANTIAL DENT IN THE COWL. SUPPLEMENTAL INFO FROM ACN 552201: AFTER RECEIVING GUIDE MAN'S STOP SIGNAL; CAPT PULLED UP PARKING BRAKE HANDLE AND INSTRUCTED ME TO SHUT DOWN ENG. I LOOKED UP TO CLOSE ENG BLEED VALVE AND SHUT DOWN ENG. WHEN I LOOKED DOWN; I ASKED 'ARE WE MOVING?' AND THEN WE FELT THE THUD WHEN THE L ENG HIT THE JETWAY. IT WAS A CLR DAY AND WE HAD NO CONFUSION ON ANY SIGNALS. THE PARKING BRAKE FAILED TO SET AND THE GUIDE MAN DID NOT CHOCK THE TIRES. BY THE TIME EITHER OF US NOTICED WE WERE MOVING; THERE WAS NO TIME TO BRAKE BEFORE HITTING THE JETWAY.