Narrative:

Arrived isp from bwi. Visual approach to runway 24. Departed isp to bwi. ATIS changed during pushback. First officer called for taxi. Both of us were expecting runway 24. Both of us thought we'd been cleared to runway 24. Began taxi to runway 24. Approaching runway 33L, I looked both ways and saw nothing. Sun was in my eyes when I looked right. I had my seat slightly higher than normal trying to keep the sun out of my eyes. 1/2 way across runway 33L, first officer looked up and to the right and said, 'what's that airplane doing there?' at that point a B737-200 passed overhead. I asked ground control if we had been cleared to cross runway 33L. Ground control said no. I then asked what they wanted us to do. We were given a taxi clearance neither of us understood. I asked for the clearance to be repeated. We were given a clearance to continue on taxiway east, runway 24, runway 33R, hold short of runway 33L. This we did. We changed to tower. They asked us to call isp tower when we got to bwi. This I did. Having just landed on runway 24, having the latest ATIS giving runway 24, we were expecting runway 24. Much more attention should be paid to the clearance. If there is any doubt, stop and ask. Supplemental information from acn 528566: when I called for taxi I thought we were told to taxi to runway 24, where we had just landed. We proceeded to taxi to runway 24 and as we were doing our pretkof checklist, I paused to make sure we were clear of the right side as we were crossing runway 33L. I saw an aircraft coming in for a landing on runway 33L. I exclaimed to the captain, 'what is that aircraft doing there?!' at that point I saw him pwring up to go around. The captain then asked ground if we were cleared to runway 24 and they replied no. We were then given taxi instructions to get back to runway 33L.

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Original NASA ASRS Text

Title: TAXIING OUT FOR TKOF, A B737 CREW AT ISP BOTH INCORRECTLY THOUGHT THEY WERE CLRED TO RWY 24 AND CROSSED RWY 31 CAUSING A B737 TO GO AROUND.

Narrative: ARRIVED ISP FROM BWI. VISUAL APCH TO RWY 24. DEPARTED ISP TO BWI. ATIS CHANGED DURING PUSHBACK. FO CALLED FOR TAXI. BOTH OF US WERE EXPECTING RWY 24. BOTH OF US THOUGHT WE'D BEEN CLRED TO RWY 24. BEGAN TAXI TO RWY 24. APCHING RWY 33L, I LOOKED BOTH WAYS AND SAW NOTHING. SUN WAS IN MY EYES WHEN I LOOKED R. I HAD MY SEAT SLIGHTLY HIGHER THAN NORMAL TRYING TO KEEP THE SUN OUT OF MY EYES. 1/2 WAY ACROSS RWY 33L, FO LOOKED UP AND TO THE R AND SAID, 'WHAT'S THAT AIRPLANE DOING THERE?' AT THAT POINT A B737-200 PASSED OVERHEAD. I ASKED GND CTL IF WE HAD BEEN CLRED TO CROSS RWY 33L. GND CTL SAID NO. I THEN ASKED WHAT THEY WANTED US TO DO. WE WERE GIVEN A TAXI CLRNC NEITHER OF US UNDERSTOOD. I ASKED FOR THE CLRNC TO BE REPEATED. WE WERE GIVEN A CLRNC TO CONTINUE ON TXWY E, RWY 24, RWY 33R, HOLD SHORT OF RWY 33L. THIS WE DID. WE CHANGED TO TWR. THEY ASKED US TO CALL ISP TWR WHEN WE GOT TO BWI. THIS I DID. HAVING JUST LANDED ON RWY 24, HAVING THE LATEST ATIS GIVING RWY 24, WE WERE EXPECTING RWY 24. MUCH MORE ATTN SHOULD BE PAID TO THE CLRNC. IF THERE IS ANY DOUBT, STOP AND ASK. SUPPLEMENTAL INFO FROM ACN 528566: WHEN I CALLED FOR TAXI I THOUGHT WE WERE TOLD TO TAXI TO RWY 24, WHERE WE HAD JUST LANDED. WE PROCEEDED TO TAXI TO RWY 24 AND AS WE WERE DOING OUR PRETKOF CHKLIST, I PAUSED TO MAKE SURE WE WERE CLR OF THE R SIDE AS WE WERE XING RWY 33L. I SAW AN ACFT COMING IN FOR A LNDG ON RWY 33L. I EXCLAIMED TO THE CAPT, 'WHAT IS THAT ACFT DOING THERE?!' AT THAT POINT I SAW HIM PWRING UP TO GO AROUND. THE CAPT THEN ASKED GND IF WE WERE CLRED TO RWY 24 AND THEY REPLIED NO. WE WERE THEN GIVEN TAXI INSTRUCTIONS TO GET BACK TO RWY 33L.

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.