Narrative:

I coordinated with the local north controller to cross runway 26R at runway 21. I was given permission by the local controller to cross the runway. I instructed aircraft #1 to cross runway 26R at runway 21 as coordinated with local north. As aircraft #1 was crossing runway 26R, I observed aircraft #2 on departure roll on runway 26R. I estimate horizontal separation to have been 1500 ft. I believe the problem arose because the local north controller forgot he approved the runway crossing. The local north controller also failed to scan the runway prior to issuing takeoff clearance to aircraft #2. Callback conversation with reporter revealed the following information: reporter confirmed the fact that after discussing this matter with the local controller, the local controller did forget that he had approved the reporter's runway crossing request prior to clearing his aircraft for takeoff.

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Original NASA ASRS Text

Title: TWR LCL CTLR CLRED A CHEROKEE FOR TKOF WHEN AN EXPERIMENTAL LIGHT ACFT HAD BEEN CLRED MIDFIELD ACROSS THE RWY RESULTING IN A POTENTIAL GND COLLISION.

Narrative: I COORDINATED WITH THE LCL N CTLR TO CROSS RWY 26R AT RWY 21. I WAS GIVEN PERMISSION BY THE LCL CTLR TO CROSS THE RWY. I INSTRUCTED ACFT #1 TO CROSS RWY 26R AT RWY 21 AS COORDINATED WITH LCL N. AS ACFT #1 WAS XING RWY 26R, I OBSERVED ACFT #2 ON DEP ROLL ON RWY 26R. I ESTIMATE HORIZ SEPARATION TO HAVE BEEN 1500 FT. I BELIEVE THE PROB AROSE BECAUSE THE LCL N CTLR FORGOT HE APPROVED THE RWY CROSSING. THE LCL N CTLR ALSO FAILED TO SCAN THE RWY PRIOR TO ISSUING TKOF CLRNC TO ACFT #2. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR CONFIRMED THE FACT THAT AFTER DISCUSSING THIS MATTER WITH THE LCL CTLR, THE LCL CTLR DID FORGET THAT HE HAD APPROVED THE RPTR'S RWY XING REQUEST PRIOR TO CLRING HIS ACFT FOR TKOF.

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.