Narrative:

Aircraft #1 was in position on an intersecting runway waiting for an medium large transport to clear onto a taxiway. Aircraft #2 was on final approximately 2.5 mi out to the other runway. Aircraft #1 was cleared for takeoff, then questioned the departure heading and then understood. The controller turned back to see aircraft #2 on a mi final then turned to see the position of aircraft #1 aircraft #1 had commenced departure roll and in the controller's judgement had the takeoff clearance been cancelled the 2 aircraft would have barely missed at the runway intersection. Aircraft #2 was rolling out on the other runway when aircraft #1 was airborne and passed over aircraft #2 about 100' vertical and 500' horizontal.

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Original NASA ASRS Text

Title: DEP CROSSED OVER TOP OF LNDG MLG ROLLING OUT ON INTERSECTING RWYS.

Narrative: ACFT #1 WAS IN POS ON AN INTERSECTING RWY WAITING FOR AN MLG TO CLR ONTO A TXWY. ACFT #2 WAS ON FINAL APPROX 2.5 MI OUT TO THE OTHER RWY. ACFT #1 WAS CLRED FOR TKOF, THEN QUESTIONED THE DEP HDG AND THEN UNDERSTOOD. THE CTLR TURNED BACK TO SEE ACFT #2 ON A MI FINAL THEN TURNED TO SEE THE POS OF ACFT #1 ACFT #1 HAD COMMENCED DEP ROLL AND IN THE CTLR'S JUDGEMENT HAD THE TKOF CLRNC BEEN CANCELLED THE 2 ACFT WOULD HAVE BARELY MISSED AT THE RWY INTXN. ACFT #2 WAS ROLLING OUT ON THE OTHER RWY WHEN ACFT #1 WAS AIRBORNE AND PASSED OVER ACFT #2 ABOUT 100' VERT AND 500' HORIZ.

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.