Narrative:

Originally cleared into position and hold runway 22L mdw. While turning corner controller cleared us for takeoff. An medium large transport was cleared before us. I believe controller thought we were still position and hold (which was first clearance). While on takeoff roll other aircraft was cleared across runway 22L downfield. Local controller said it was 'his fault.' we never heard controller tell other aircraft to cross. Other aircraft crossed, we continued takeoff after momentary reduction in power, we re-established takeoff power.

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Original NASA ASRS Text

Title: SMT CLEARED FOR TKOF AT SAME TIME ANOTHER ACFT WAS CLEARED TO CROSS THE ACTIVE RWY. CTLR ERROR ADMITTED.

Narrative: ORIGINALLY CLRED INTO POS AND HOLD RWY 22L MDW. WHILE TURNING CORNER CTLR CLRED US FOR TKOF. AN MLG WAS CLRED BEFORE US. I BELIEVE CTLR THOUGHT WE WERE STILL POS AND HOLD (WHICH WAS FIRST CLRNC). WHILE ON TKOF ROLL OTHER ACFT WAS CLRED ACROSS RWY 22L DOWNFIELD. LCL CTLR SAID IT WAS 'HIS FAULT.' WE NEVER HEARD CTLR TELL OTHER ACFT TO CROSS. OTHER ACFT CROSSED, WE CONTINUED TKOF AFTER MOMENTARY REDUCTION IN PWR, WE RE-ESTABLISHED TKOF POWER.

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.