MD80 FLT ATTENDANT FOUND A BOMB IN A PAX BACKPACK.

Narrative

ON CLBOUT; FLT ATTENDANT CALLED THE COCKPIT AND SAID SHE FOUND A BAG THAT LOOKED LIKE A BOMB. SHE DESCRIBED A CYLINDER WITH WIRES; A BROKEN HAIRDRYER; A TIMING DEVICE WITH A KEYPAD AND A CIRCUIT BOARD. I TOLD ATC WE NEEDED TO MAINTAIN OUR PRESENT ALT (15000 FT) THAT WE WERE DEALING WITH A PROB. I HAD THE FO GO BACK AND LOOK AT THE BAG AND HE RETURNED WITH WHAT HE DESCRIBED AS IT DEFINITELY LOOKING LIKE A BOMB. I REQUESTED AN EMER RETURN TO SEA STRAIGHT IN (OPPOSITE DIRECTION) RWY 34R. TOLD ATC WE HAD A SUSPICIOUS BAG ON BOARD THAT LOOKED LIKE A BOMB. WE WERE GIVEN VECTORS TO RWY 34R AT SEA. UPON SWITCHING FREQ TO THE TWR; WE WERE TOLD THEY WANTED US AFTER LNDG TO TAXI TO THE REMOTE LOCATION; WHICH WE DID. PLANNING INITIALLY TO USE THE FORWARD AIR STAIRS TO HAVE THE PAX EXIT THE ACFT; WE ADDITIONALLY KEPT THE ACFT CONFIGURED IN THE EVENT AN EVAC WAS NEEDED. AFTER STOPPING AND SEEING THE LENGTH OF TIME IT WAS GOING TO TAKE TO EXTEND THE FORWARD STAIRS AND TO GET THE PAX OFF THE ACFT; THE RISK OF THE ADDITIONAL TIME ONBOARD THE ACFT OUTWEIGHED THE RISK OF POTENTIAL INJURY TO PAX BY EVAC AND I ORDERED AN EVAC OF THE ACFT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: CREW WAS FLYING AN MD80 ACFT. THE BOMB WAS AN ARPT SECURITY DEVICE USED TO CHECK ARPT X-RAY SECURITY PERSONNEL. AT ARPT SECURITY THE BOMB WAS DISCOVERED AND PLACED ASIDE. AN UNACCOMPANIED MINOR WAS BEING PUT ON A FLT BY HIS GRANDMOTHER. HE HAD A BACKPACK THAT WAS THE SAME AS THE ONE THAT THE TEST BOMB HAD BEEN PLACED IN. AFTER HE FINISHED WITH SECURITY HE TOOK THE WRONG BACKPACK ONTO THE ACFT; THE ONE WITH THE BOMB. AFTER TKOF HE ASKED THE FLT ATTENDANT TO GET HIS CRAYONS FROM THE BACKPACK. THIS IS WHEN THE BOMB WAS FOUND. THE CAPT DID NOT CONSIDER PLACING THE BOMB IN THE LEAST RISK LOCATION AS THIS IS IN THE UNPRESSURIZED TAIL CONE. THE CABIN ALT AT THE TIME WAS 15000 FT AND THE CAPT DID NOT WANT TO DEPRESSURIZE THE ACFT FURTHER. THE CAPT STRONGLY SUGGESTS THAT ALL FAA SECURITY TEST DEVICES BE PAINTED IN AN INTL ORANGE WITH 'TEST DEVICE' PROMINENTLY LABELED ON THE DEVICE. IN THIS WAY THE FLT WOULD NOT HAVE BEEN PLACED IN SUCH A HARROWING POS.