Narrative:

From the cargo ramp we were cleared to taxi to runway 20, about 500 yards away. I could see the end of the runway and taxiway, but had mistaken one for the other. As I turned the corner onto the runway, realizing my mistake, I commanded the first officer 'tell the tower we are on the runway.' ATC responded by clearing us across the runway to the taxiway. No conflict with traffic occurred. ATC made no mention of our mistake.

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Original NASA ASRS Text

Title: DC9-33 CAPT INADVERTENTLY TAXIED ONTO RWY DURING TAXI OUT DUE TO MISTAKING THE RWY FOR THE TXWY.

Narrative: FROM THE CARGO RAMP WE WERE CLRED TO TAXI TO RWY 20, ABOUT 500 YARDS AWAY. I COULD SEE THE END OF THE RWY AND TAXIWAY, BUT HAD MISTAKEN ONE FOR THE OTHER. AS I TURNED THE CORNER ONTO THE RWY, REALIZING MY MISTAKE, I COMMANDED THE FO 'TELL THE TWR WE ARE ON THE RWY.' ATC RESPONDED BY CLRING US ACROSS THE RWY TO THE TXWY. NO CONFLICT WITH TFC OCCURRED. ATC MADE NO MENTION OF OUR MISTAKE.

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.