Narrative:

Taxi instructions in phl were to taxi south on taxiway east, hold short of runway 9L. We complied and then were cleared to cross runway 9L on taxiway east. I switched on our strobes and wing ice lights and proceeded to cross. We could see an aircraft on the departure end of runway 9L but no movement was visible. As we entered the runway, we were instructed by ground control to taxi across runway 9L without delay due to traffic departing runway 9L. As we exited the other side of runway 9L on taxiway east, we could see a narrow body, twin jet approaching from our right, lights on, taking off from runway 9L. As we switched to tower frequency we heard that same departing flight query the tower controller, 'are you aware an aircraft crossed the runway in front of us on the takeoff roll?' the tower controller replied 'yes' after a long pause. Had we seen that the flight was moving on the runway for takeoff with lights on, we would not have proceeded across runway 9L and would have held short. As we cleared the runway, the departing flight was likely between taxiway T and taxiway K4 on the takeoff roll. It should not have been cleared for takeoff before we entered the runway which is what probably happened. I will continue to be vigilant in checking for landing/departing traffic as well as crossing/hold short clrncs before crossing any runway. Supplemental information from acn 556334: aircraft cleared for takeoff, questioned whether or not I knew that another aircraft had crossed the runway ahead of him. Supplemental information from acn 556335: I verbally requested approval to cross runway 9L at taxiway east with aircraft X. The local east controller verbally approved my request and I issued instructions to aircraft X to cross runway 9L at taxiway east. At no time did the amass alarm issue any warnings.

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Original NASA ASRS Text

Title: AN ACR IS CLRED TO CROSS RWY 9L AT PHL, PA. ANOTHER ACR ON TKOF ROLL ON THAT RWY QUESTIONS THE LCL CTLR ABOUT THE CONFLICT ONCE HE IS AIRBORNE.

Narrative: TAXI INSTRUCTIONS IN PHL WERE TO TAXI S ON TXWY E, HOLD SHORT OF RWY 9L. WE COMPLIED AND THEN WERE CLRED TO CROSS RWY 9L ON TXWY E. I SWITCHED ON OUR STROBES AND WING ICE LIGHTS AND PROCEEDED TO CROSS. WE COULD SEE AN ACFT ON THE DEP END OF RWY 9L BUT NO MOVEMENT WAS VISIBLE. AS WE ENTERED THE RWY, WE WERE INSTRUCTED BY GND CTL TO TAXI ACROSS RWY 9L WITHOUT DELAY DUE TO TFC DEPARTING RWY 9L. AS WE EXITED THE OTHER SIDE OF RWY 9L ON TXWY E, WE COULD SEE A NARROW BODY, TWIN JET APCHING FROM OUR R, LIGHTS ON, TAKING OFF FROM RWY 9L. AS WE SWITCHED TO TWR FREQ WE HEARD THAT SAME DEPARTING FLT QUERY THE TWR CTLR, 'ARE YOU AWARE AN ACFT CROSSED THE RWY IN FRONT OF US ON THE TKOF ROLL?' THE TWR CTLR REPLIED 'YES' AFTER A LONG PAUSE. HAD WE SEEN THAT THE FLT WAS MOVING ON THE RWY FOR TKOF WITH LIGHTS ON, WE WOULD NOT HAVE PROCEEDED ACROSS RWY 9L AND WOULD HAVE HELD SHORT. AS WE CLRED THE RWY, THE DEPARTING FLT WAS LIKELY BTWN TXWY T AND TXWY K4 ON THE TKOF ROLL. IT SHOULD NOT HAVE BEEN CLRED FOR TKOF BEFORE WE ENTERED THE RWY WHICH IS WHAT PROBABLY HAPPENED. I WILL CONTINUE TO BE VIGILANT IN CHKING FOR LNDG/DEPARTING TFC AS WELL AS XING/HOLD SHORT CLRNCS BEFORE XING ANY RWY. SUPPLEMENTAL INFO FROM ACN 556334: ACFT CLRED FOR TKOF, QUESTIONED WHETHER OR NOT I KNEW THAT ANOTHER ACFT HAD CROSSED THE RWY AHEAD OF HIM. SUPPLEMENTAL INFO FROM ACN 556335: I VERBALLY REQUESTED APPROVAL TO CROSS RWY 9L AT TXWY E WITH ACFT X. THE LCL E CTLR VERBALLY APPROVED MY REQUEST AND I ISSUED INSTRUCTIONS TO ACFT X TO CROSS RWY 9L AT TXWY E. AT NO TIME DID THE AMASS ALARM ISSUE ANY WARNINGS.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.