Narrative:

After pushback in sfo, the departing runway changed from runway 1L to runway 10L. Ground control cleared us to taxi from abeam gate xx to runway 10R via taxiway B and taxiway U. I asked the captain if he understood the instructions and he acknowledged. As we taxied east on taxiway B, I told the captain that I would be 'heads down' while I made the required changes to the FMGC and calculated the performance for the new runway. While still on taxiway B, ground told us to give way to an air carrier Y jet turning on taxiway U from taxiway B and he would be our sequence. I acknowledged the call and confirmed the captain understood. I told the captain I would be heads down again to finish the changes for the new runway. While still heads down, ground control informed us that we had crossed runway 10R without permission. A very short taxi distance combined with a high workload on my part left little time for me to back up the captain while he taxied. Given a similar situation, I would try to vary the time from heads up to heads down to better back up the captain during taxi or wait until the aircraft is stopped to make required changes.

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Original NASA ASRS Text

Title: A320 CREW AFTER PUSHBACK SFO ARE ADVISED DEPARTING RWY CHANGED FROM RWY 1L TO RWY 10L AND WHILE TAXIING CROSS RWY 10R WITHOUT CLRNC.

Narrative: AFTER PUSHBACK IN SFO, THE DEPARTING RWY CHANGED FROM RWY 1L TO RWY 10L. GND CTL CLRED US TO TAXI FROM ABEAM GATE XX TO RWY 10R VIA TXWY B AND TXWY U. I ASKED THE CAPT IF HE UNDERSTOOD THE INSTRUCTIONS AND HE ACKNOWLEDGED. AS WE TAXIED E ON TXWY B, I TOLD THE CAPT THAT I WOULD BE 'HEADS DOWN' WHILE I MADE THE REQUIRED CHANGES TO THE FMGC AND CALCULATED THE PERFORMANCE FOR THE NEW RWY. WHILE STILL ON TXWY B, GND TOLD US TO GIVE WAY TO AN ACR Y JET TURNING ON TXWY U FROM TXWY B AND HE WOULD BE OUR SEQUENCE. I ACKNOWLEDGED THE CALL AND CONFIRMED THE CAPT UNDERSTOOD. I TOLD THE CAPT I WOULD BE HEADS DOWN AGAIN TO FINISH THE CHANGES FOR THE NEW RWY. WHILE STILL HEADS DOWN, GND CTL INFORMED US THAT WE HAD CROSSED RWY 10R WITHOUT PERMISSION. A VERY SHORT TAXI DISTANCE COMBINED WITH A HIGH WORKLOAD ON MY PART LEFT LITTLE TIME FOR ME TO BACK UP THE CAPT WHILE HE TAXIED. GIVEN A SIMILAR SIT, I WOULD TRY TO VARY THE TIME FROM HEADS UP TO HEADS DOWN TO BETTER BACK UP THE CAPT DURING TAXI OR WAIT UNTIL THE ACFT IS STOPPED TO MAKE REQUIRED CHANGES.

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.