Narrative:

After pushback from gate and upon issuance of taxi instructions to proceed to runway 12R, the captain began taxiing. The taxi checklist was called for and I extended the slats/flaps. I am especially thorough with proper positioning of the slats/flaps and place much emphasis with the correct completion of the taxi checklist. As the aircraft was turned to the right away from the jetway, I saw construction on the ramp now to the capts left and then another taxiway that was illuminated in red lights 'no entry.' this I subsequently learned was the high speed turnoff for runway 12R. I cleared our aircraft on the right to avoid obstructions and also observed an air carrier Y medium large transport which was instructed to follow us. After clearing, I continued with the checklist doublechking slat/flap, cg and stabilizer settings. The dimly lit cockpit with poorly lit indications and markings distraction me from really insuring where captain was taking us. As my attention was still focused on these details he started a left turn off the ramp onto the perpendicular stub between the ramp and what I mistakenly thought was another taxiway. At that moment he made a statement about a fly or bug flying about in the cockpit. He then opened HSI dv window and announced that we were going to remove said intruder. Now my attention was further eroded with this problem only to find us in another left turn, now onto runway 12R. Now the unison 'oh, bleep'. The sharp controller working local and ground control saw us and then issued a 'go around' to an aircraft on final. Just prior to entering 12R I started to question but it was too late. The captain then taxied clear of 12R on the reverse high speed taxiway and proceeded on the proper taxiway to 12R.

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Original NASA ASRS Text

Title: ACR MLG UNAUTH TAXI AND RWY TRANSGRESS CAUSES A GAR AT SAT.

Narrative: AFTER PUSHBACK FROM GATE AND UPON ISSUANCE OF TAXI INSTRUCTIONS TO PROCEED TO RWY 12R, THE CAPT BEGAN TAXIING. THE TAXI CHKLIST WAS CALLED FOR AND I EXTENDED THE SLATS/FLAPS. I AM ESPECIALLY THOROUGH WITH PROPER POSITIONING OF THE SLATS/FLAPS AND PLACE MUCH EMPHASIS WITH THE CORRECT COMPLETION OF THE TAXI CHKLIST. AS THE ACFT WAS TURNED TO THE R AWAY FROM THE JETWAY, I SAW CONSTRUCTION ON THE RAMP NOW TO THE CAPTS L AND THEN ANOTHER TAXIWAY THAT WAS ILLUMINATED IN RED LIGHTS 'NO ENTRY.' THIS I SUBSEQUENTLY LEARNED WAS THE HIGH SPD TURNOFF FOR RWY 12R. I CLRED OUR ACFT ON THE R TO AVOID OBSTRUCTIONS AND ALSO OBSERVED AN ACR Y MLG WHICH WAS INSTRUCTED TO FOLLOW US. AFTER CLRING, I CONTINUED WITH THE CHKLIST DOUBLECHKING SLAT/FLAP, CG AND STABILIZER SETTINGS. THE DIMLY Lit COCKPIT WITH POORLY LIT INDICATIONS AND MARKINGS DISTR ME FROM REALLY INSURING WHERE CAPT WAS TAKING US. AS MY ATTN WAS STILL FOCUSED ON THESE DETAILS HE STARTED A L TURN OFF THE RAMP ONTO THE PERPENDICULAR STUB BTWN THE RAMP AND WHAT I MISTAKENLY THOUGHT WAS ANOTHER TAXIWAY. AT THAT MOMENT HE MADE A STATEMENT ABOUT A FLY OR BUG FLYING ABOUT IN THE COCKPIT. HE THEN OPENED HSI DV WINDOW AND ANNOUNCED THAT WE WERE GOING TO REMOVE SAID INTRUDER. NOW MY ATTN WAS FURTHER ERODED WITH THIS PROBLEM ONLY TO FIND US IN ANOTHER L TURN, NOW ONTO RWY 12R. NOW THE UNISON 'OH, BLEEP'. THE SHARP CTLR WORKING LCL AND GND CTL SAW US AND THEN ISSUED A 'GAR' TO AN ACFT ON FINAL. JUST PRIOR TO ENTERING 12R I STARTED TO QUESTION BUT IT WAS TOO LATE. THE CAPT THEN TAXIED CLR OF 12R ON THE REVERSE HIGH SPD TAXIWAY AND PROCEEDED ON THE PROPER TAXIWAY TO 12R.

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.