METRO MAY FINDS CLUES ABOUT CRASH

[PHOTO COURTESY OF GOOGLEIMAGES.]

METRO OFFICIALS MAY HAVE AN IDEA OF WHAT CONTRIBUTED TO LAST MONTH'S TRAGIC RED LINE TRAIN CRASH.

OFFICIALS SAY THE MALFUNCTION WAS TRACED TO "FLICKERING" IN A TRACK CIRCUIT. ITS BEING CALLED A "FREAK OCCURRENCE" THAT SOME AT METRO SAY THEY NEVER KNEW WAS POSSIBLE.

BUT EXPERTS SAY THAT THIS TYPE OF MALFUNCTION IS KNOWN AND PREVENTABLE. IN FACT, THE BAY AREA TRANSIT SYSTEM IN CALIFORNIA, RECOGNIZED THIS POSSIBILITY AND INSTALLED A BACKUP SYSTEM, CALLED THE SEQUENTIAL OCCUPANCY RELEASE SYSTEM, WHICH PROVIDES PROTECTION AGAINST FLICKERING TRACK CIRCUITRY. METRO HAS NOT.

METRO OFFICIALS SAY THAT LIKE OTHER SYSTEMS IN THE US, ITS SYSTEM IS DESIGNED TO BE "FAIL SAFE".

ACCORDING TO METRO, ITS SYSTEM RELIES ON THE HELP OF TRACK CIRCUITS TO KEEP TRAINS AT SAFE DISTANCES. THESE CIRCUITS ARE DESIGNED TO DETECT TRAINS AND SEND THOSE FREQUENCIES TO THE NEXT TRAIN. IF IN FACT A TRAIN GETS TOO CLOSE, THE SYSTEM IS SUPPOSED TO SEND A "ZERO" SPEED SIGNAL THAT WOULD FORCE THE MOVING TRAIN TO STOP.

THE NATIONAL TRANSPORTATION SAFETY BOARD SAYS THAT IF THE CIRCUITS DID MALFUNCTION ON THE DAY OF THE JUNE 22ND RED-LINE CRASH, THEN THEY SENT A "CLEAR" SIGNAL TO THE STRIKING TRAIN.

-LYNEE COAN, GT NEWS