Narrative:

After clearing runway 7R we were cleared to taxi charlie, foxtrot. This clearance was repeated once again while proceeding east on taxiway C. Approaching runway 7L all outside lights were turned on and visual inspection was made to the right and left prior to crossing. At approximately half way across the runway I heard the controller tell an aircraft to 'line up and wait' runway 7L. I did observe an aircraft leave the taxiway and proceed to the approach end of runway 7L with a nose gear light illuminated. After clearing the runway, the controller asked us 'who gave us clearance to cross?' after a very short discussion, we changed to taxiway.

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Original NASA ASRS Text

Title: B777 CREW HAD RWY INCURSION AT EDDF.

Narrative: AFTER CLRING RWY 7R WE WERE CLRED TO TAXI CHARLIE, FOXTROT. THIS CLRNC WAS REPEATED ONCE AGAIN WHILE PROCEEDING E ON TXWY C. APCHING RWY 7L ALL OUTSIDE LIGHTS WERE TURNED ON AND VISUAL INSPECTION WAS MADE TO THE R AND L PRIOR TO XING. AT APPROX HALF WAY ACROSS THE RWY I HEARD THE CTLR TELL AN ACFT TO 'LINE UP AND WAIT' RWY 7L. I DID OBSERVE AN ACFT LEAVE THE TXWY AND PROCEED TO THE APCH END OF RWY 7L WITH A NOSE GEAR LIGHT ILLUMINATED. AFTER CLRING THE RWY, THE CTLR ASKED US 'WHO GAVE US CLRNC TO CROSS?' AFTER A VERY SHORT DISCUSSION, WE CHANGED TO TXWY.

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.