Narrative:

Original taxi clearance to runway 32L at T10 following a regional jet. Taxi instructions changed after initial turn to taxi to runway 4L via a, A6 ,J ,west, crew was busy doing checklist, so busy reading and doing checklist, first officer busy verifying checklist, captain busy taxiing and doing checklist. Missed turn at taxiway 'west' and proceeded to runway 9L. Tower cleared us into position and hold runway 4L prior to us making turn at west and we just crossed the hold line for runway 9L when we realized we were on runway 9L instead of runway 4L. No planes went around and tower then cleared us for takeoff from runway 9L. No incursions. Callback conversation with reporter revealed the following information: reporter said it was very busy at the time. He said the ground controller was issuing taxi instructions to 5 or 6 aircraft at a time with little or no response from pilots. He also said their taxi instructions included a statement to contact tower. He stated the turn onto taxiway west for runway 04L may have been missed because they had been told to follow a CL65 going to runway 09L and the crew was busy starting the third engine and doing the checklist. He said the captain, following an instruction to go into position and hold on runway 04L, realized his mistake about 10 ft past the runway 09L hold lines.

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Original NASA ASRS Text

Title: B727 CREW TAXIING TO RWY AT ORD IS INSTRUCTED TO FOLLOW A CL65 THAT WAS GOING TO A DIFFERENT RWY.

Narrative: ORIGINAL TAXI CLRNC TO RWY 32L AT T10 FOLLOWING A REGIONAL JET. TAXI INSTRUCTIONS CHANGED AFTER INITIAL TURN TO TAXI TO RWY 4L VIA A, A6 ,J ,W, CREW WAS BUSY DOING CHKLIST, SO BUSY READING AND DOING CHKLIST, FO BUSY VERIFYING CHKLIST, CAPT BUSY TAXIING AND DOING CHKLIST. MISSED TURN AT TXWY 'W' AND PROCEEDED TO RWY 9L. TWR CLRED US INTO POS AND HOLD RWY 4L PRIOR TO US MAKING TURN AT W AND WE JUST CROSSED THE HOLD LINE FOR RWY 9L WHEN WE REALIZED WE WERE ON RWY 9L INSTEAD OF RWY 4L. NO PLANES WENT AROUND AND TOWER THEN CLRED US FOR TKOF FROM RWY 9L. NO INCURSIONS. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR SAID IT WAS VERY BUSY AT THE TIME. HE SAID THE GND CTLR WAS ISSUING TAXI INSTRUCTIONS TO 5 OR 6 ACFT AT A TIME WITH LITTLE OR NO RESPONSE FROM PLTS. HE ALSO SAID THEIR TAXI INSTRUCTIONS INCLUDED A STATEMENT TO CONTACT TWR. HE STATED THE TURN ONTO TXWY W FOR RWY 04L MAY HAVE BEEN MISSED BECAUSE THEY HAD BEEN TOLD TO FOLLOW A CL65 GOING TO RWY 09L AND THE CREW WAS BUSY STARTING THE THIRD ENGINE AND DOING THE CHKLIST. HE SAID THE CAPTAIN, FOLLOWING AN INSTRUCTION TO GO INTO POS AND HOLD ON RWY 04L, REALIZED HIS MISTAKE ABOUT 10 FT PAST THE RWY 09L HOLD LINES.

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.