AFTER LNDG PHL; A B737 CREW RECEIVE CLRNC TO CROSS RWY 9L AND EXPEDITE. WHEN PRIOR TO XING; THEY HEAR CTLR CLR TFC FOR TKOF.

Narrative

AFTER LNDG ON RWY 9R AT PHL; TWR DIRECTED THAT WE PROCEED ON THE PARALLEL; TURN L ON TXWY N; AND HOLD SHORT OF RWY 9L. FO ACKNOWLEDGED AND WE PROCEEDED. JUST BEFORE MAKING THE L TURN ONTO TXWY N; TWR ADVISED US TO CROSS RWY 9L WITHOUT DELAY AND CONTACT GND. AFTER MAKING THE L TURN ONTO TXWY N; I ADDED PWR TO KEEP MY TAXI SPD UP. JUST PASSING TXWY P; WE HEARD TWR CLR AN ACFT FOR TKOF ON RWY 9L AND ANOTHER ONE ONTO HOLD. I EVALUATED OUR POS; SAW AN ACFT IN THE TKOF POS ON RWY 9L WITH ALL ITS LIGHTS ON. WE WERE NOT SURE WE COULD STOP SHORT OF RWY 9L AND SO I ADDED PWR TO ENSURE A SAFE XING WHILE THE FO CALLED TWR TO CONFIRM OUR CLRNC ACROSS THE RWY. TWR REPLIED THAT THEY THOUGHT WE HAD ALREADY CROSSED THE RWY; CONFIRMED WE WERE CLRED TO DO SO AND SAID NOTHING MORE. IF WE HAD NOT ADDED PWR TO CROSS THAT RWY IN AN EXPEDITIOUS MANNER; OUR PRESENCE ON THE RWY MAY HAVE CAUSED THE ACFT ON TKOF ROLL TO INITIATE AN ABORT OR OTHER MANEUVER. MY FO AND I AGREED THIS WAS A VERY DANGEROUS SIT. AT NIGHT AND EVEN THOUGH WE WERE OFF THE RWY WELL BEFORE THE OTHER ACFT PASSED OUR POS; WE WERE NOT EVEN TO THE RWY (BUT WERE COMMITTED) WHEN TWR CLRED THE OTHER ACFT FOR TKOF. WX WAS CLR BUT IT WAS A DARK NIGHT. MY ONLY OTHER OPTION WOULD HAVE BEEN A MAX EFFORT STOP THAT MAY HAVE RESULTED IN RWY INCURSION WITH A VERY SERIOUS POTENTIAL THREAT TO THE ACFT TAKING OFF. THIS WAS A ROCK AND A HARD PLACE THAT WAS CAUSED BY TWR NOT KEEPING TRACK OF PLANES ON THE GND.