Narrative:

When taxiing out for takeoff, I missed the correct turn after being cleared to taxi for takeoff. Instead of turning left on the cargo ramp, which would turn into taxiway U (the parallel on my side of the runway), I taxied onto taxiway B and turned left onto the runway, thinking it was the parallel. As soon as I got the nose of the aircraft up onto the runway, I could see it was a runway, not a taxiway, so I stopped. I tried to contact ground control/tower but since it was a combined operation (1 person) he was unable to be reached because he was continuously talking without stop for several mins. I could see an aircraft 5 mi or so on final closing in. I couldn't back up plus the taxiway was too narrow to turn around. Eventually I realized I was going to have to take action on my own since the ground/tower was unaware of the situation and unreachable. The quickest way to clear the runway was to proceed directly across, so I did as fast as possible. When across, I finally managed to call tower to let him know I had cleared the runway and why. His response was to send the other airplane on final around. Neither the first officer nor myself recall seeing a lighted red runway sign prior to entering the runway.

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Original NASA ASRS Text

Title: CAPT OF A CARGO DC9 FAILED TO FOLLOW TAXI INSTRUCTIONS TO TKOF RWY RESULTING IN XING THE RWY AND CAUSING TWR TO SEND ANOTHER ACFT ON FINAL AROUND.

Narrative: WHEN TAXIING OUT FOR TKOF, I MISSED THE CORRECT TURN AFTER BEING CLRED TO TAXI FOR TKOF. INSTEAD OF TURNING L ON THE CARGO RAMP, WHICH WOULD TURN INTO TXWY U (THE PARALLEL ON MY SIDE OF THE RWY), I TAXIED ONTO TXWY B AND TURNED L ONTO THE RWY, THINKING IT WAS THE PARALLEL. AS SOON AS I GOT THE NOSE OF THE ACFT UP ONTO THE RWY, I COULD SEE IT WAS A RWY, NOT A TXWY, SO I STOPPED. I TRIED TO CONTACT GND CTL/TWR BUT SINCE IT WAS A COMBINED OP (1 PERSON) HE WAS UNABLE TO BE REACHED BECAUSE HE WAS CONTINUOUSLY TALKING WITHOUT STOP FOR SEVERAL MINS. I COULD SEE AN ACFT 5 MI OR SO ON FINAL CLOSING IN. I COULDN'T BACK UP PLUS THE TXWY WAS TOO NARROW TO TURN AROUND. EVENTUALLY I REALIZED I WAS GOING TO HAVE TO TAKE ACTION ON MY OWN SINCE THE GND/TWR WAS UNAWARE OF THE SIT AND UNREACHABLE. THE QUICKEST WAY TO CLR THE RWY WAS TO PROCEED DIRECTLY ACROSS, SO I DID AS FAST AS POSSIBLE. WHEN ACROSS, I FINALLY MANAGED TO CALL TWR TO LET HIM KNOW I HAD CLRED THE RWY AND WHY. HIS RESPONSE WAS TO SEND THE OTHER AIRPLANE ON FINAL AROUND. NEITHER THE FO NOR MYSELF RECALL SEEING A LIGHTED RED RWY SIGN PRIOR TO ENTERING THE RWY.

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.