Narrative:

Taxiing to runway 23L tower said we were 5TH behind commuter aircraft west. Thought we were told to follow him across 28 to position on 23L. He was cleared to cross 23L and taxi into position 23R. I had some question on clearance and first officer and I discussed it and I stopped short of 23L but we were past hold short line, although we didn't know exactly where hold short line was because of snow on ground and because there may not be a hold short line for that runway. Controller was busy. Controller called up after we had already stopped and asked if we were on the runway. First officer answered 'slightly' although we were short of the runway by about 8 ft (I assume first officer meant past hold short line). Controller then sent aircraft Y on 2-3 mi final around and cleared us for takeoff. When in doubt - stop! Callback conversation with reporter revealed the following information: reporter described other aircraft involved. Says lengthy taxi clearance by tower local controller confused him and first officer. Should have held position on the ramp until tower clearance could be clarified. They were holding on wide area of ramp adjacent to runway 28. Does not recall seeing any signs showing runway 28. Any hold lines or other surface markings would have been covered by snow. Another air carrier aircraft was asking tower a lot of questions about his ATC handling and this caused some frequency congestion. Tower controller clearance to air carrier X was something like 'air carrier X follow type Y aircraft who is going to runway 23R, taxi onto runway 32, hold short of 23L'. Reporter thinks too many numbers and items in clearance.

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Original NASA ASRS Text

Title: UNAUTHORIZED RWY ENTRY BY ACR.

Narrative: TAXIING TO RWY 23L TWR SAID WE WERE 5TH BEHIND COMMUTER ACFT W. THOUGHT WE WERE TOLD TO FOLLOW HIM ACROSS 28 TO POS ON 23L. HE WAS CLRED TO CROSS 23L AND TAXI INTO POS 23R. I HAD SOME QUESTION ON CLRNC AND FO AND I DISCUSSED IT AND I STOPPED SHORT OF 23L BUT WE WERE PAST HOLD SHORT LINE, ALTHOUGH WE DIDN'T KNOW EXACTLY WHERE HOLD SHORT LINE WAS BECAUSE OF SNOW ON GND AND BECAUSE THERE MAY NOT BE A HOLD SHORT LINE FOR THAT RWY. CTLR WAS BUSY. CTLR CALLED UP AFTER WE HAD ALREADY STOPPED AND ASKED IF WE WERE ON THE RWY. FO ANSWERED 'SLIGHTLY' ALTHOUGH WE WERE SHORT OF THE RWY BY ABOUT 8 FT (I ASSUME FO MEANT PAST HOLD SHORT LINE). CTLR THEN SENT ACFT Y ON 2-3 MI FINAL AROUND AND CLRED US FOR TKOF. WHEN IN DOUBT - STOP! CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR DESCRIBED OTHER ACFT INVOLVED. SAYS LENGTHY TAXI CLRNC BY TWR LCL CTLR CONFUSED HIM AND FO. SHOULD HAVE HELD POS ON THE RAMP UNTIL TWR CLRNC COULD BE CLARIFIED. THEY WERE HOLDING ON WIDE AREA OF RAMP ADJACENT TO RWY 28. DOES NOT RECALL SEEING ANY SIGNS SHOWING RWY 28. ANY HOLD LINES OR OTHER SURFACE MARKINGS WOULD HAVE BEEN COVERED BY SNOW. ANOTHER ACR ACFT WAS ASKING TWR A LOT OF QUESTIONS ABOUT HIS ATC HANDLING AND THIS CAUSED SOME FREQ CONGESTION. TWR CTLR CLRNC TO ACR X WAS SOMETHING LIKE 'ACR X FOLLOW TYPE Y ACFT WHO IS GOING TO RWY 23R, TAXI ONTO RWY 32, HOLD SHORT OF 23L'. RPTR THINKS TOO MANY NUMBERS AND ITEMS IN CLRNC.

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.