Narrative:

After landing on 31L I made the high speed turnoff and brought the aircraft to taxi speed. The tower frequency was very congested and communication was marginal. It is unclear to the exactly what was said in our initial ground radio contact but as I nearly approached runway 31R the tower told us to 'stop'. It was at this point that I realized I nearly taxied across an active runway. Without the vigilance of the tower operator it could have been a tragic situation. After looking at the way these runways are laid out and considering the way they are used, it appears that extreme caution is necessary when transitioning from 31L, the the high speed turnoff, to november taxiway. If 31R is being used for takeoffs, the runways are so close that you no sooner land and stop when you are right up the an active runway. Supplemental information from acn 112481: after landing on 31L tower instructed to turn right on november hold short 31R. As I acknowledged, captain slowed to taxi speed. I should have paid closer attention to tower instructions instead of thinking the captain heard and understood everything. Solutions: better cockpit communication. Wait an extra 15 seconds before doing checklists. This will allow for 'seeing what's going on' instead of keep one's head in the cockpit.

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Original NASA ASRS Text

Title: ACR MLG UNAUTH RWY CROSSING AT MDW.

Narrative: AFTER LNDG ON 31L I MADE THE HIGH SPEED TURNOFF AND BROUGHT THE ACFT TO TAXI SPEED. THE TWR FREQ WAS VERY CONGESTED AND COM WAS MARGINAL. IT IS UNCLEAR TO THE EXACTLY WHAT WAS SAID IN OUR INITIAL GND RADIO CONTACT BUT AS I NEARLY APCHED RWY 31R THE TWR TOLD US TO 'STOP'. IT WAS AT THIS POINT THAT I REALIZED I NEARLY TAXIED ACROSS AN ACTIVE RWY. WITHOUT THE VIGILANCE OF THE TWR OPERATOR IT COULD HAVE BEEN A TRAGIC SITUATION. AFTER LOOKING AT THE WAY THESE RWYS ARE LAID OUT AND CONSIDERING THE WAY THEY ARE USED, IT APPEARS THAT EXTREME CAUTION IS NECESSARY WHEN TRANSITIONING FROM 31L, THE THE HIGH SPEED TURNOFF, TO NOVEMBER TXWY. IF 31R IS BEING USED FOR TKOFS, THE RWYS ARE SO CLOSE THAT YOU NO SOONER LAND AND STOP WHEN YOU ARE RIGHT UP THE AN ACTIVE RWY. SUPPLEMENTAL INFORMATION FROM ACN 112481: AFTER LNDG ON 31L TWR INSTRUCTED TO TURN RIGHT ON NOVEMBER HOLD SHORT 31R. AS I ACKNOWLEDGED, CAPT SLOWED TO TAXI SPEED. I SHOULD HAVE PAID CLOSER ATTN TO TWR INSTRUCTIONS INSTEAD OF THINKING THE CAPT HEARD AND UNDERSTOOD EVERYTHING. SOLUTIONS: BETTER COCKPIT COM. WAIT AN EXTRA 15 SECONDS BEFORE DOING CHECKLISTS. THIS WILL ALLOW FOR 'SEEING WHAT'S GOING ON' INSTEAD OF KEEP ONE'S HEAD IN THE COCKPIT.

Data retrieved from NASA's ASRS site as of August 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.