Narrative:

On ramp at hobby I, as the first officer, received clearance to taxi via red line, cross 12L and position and hold on 12R. Approaching 12R captain asked if we were cleared into position. I said yes, then completed final items of takeoff checklist. I looked out at final approach and then did double take as I saw an aircraft Y on about a 2 mi final. I told the captain. He stopped the aircraft (past hold short line). At exactly same time tower questioned whether we were on the runway. Since we were over the hold short line, I said yes. Actual position of aircraft was short of runway and displaced threshold. Air carrier Y large transport was told to go around. I told tower I/we were cleared position and hold. They said that we weren't.

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Original NASA ASRS Text

Title: ACR MLG UNAUTH RWY ENTRY WITH LGT ON SHORT FINAL.

Narrative: ON RAMP AT HOBBY I, AS THE F/O, RECEIVED CLRNC TO TAXI VIA RED LINE, CROSS 12L AND POS AND HOLD ON 12R. APCHING 12R CAPT ASKED IF WE WERE CLRED INTO POS. I SAID YES, THEN COMPLETED FINAL ITEMS OF TKOF CHKLIST. I LOOKED OUT AT FINAL APCH AND THEN DID DOUBLE TAKE AS I SAW AN ACFT Y ON ABOUT A 2 MI FINAL. I TOLD THE CAPT. HE STOPPED THE ACFT (PAST HOLD SHORT LINE). AT EXACTLY SAME TIME TWR QUESTIONED WHETHER WE WERE ON THE RWY. SINCE WE WERE OVER THE HOLD SHORT LINE, I SAID YES. ACTUAL POS OF ACFT WAS SHORT OF RWY AND DISPLACED THRESHOLD. ACR Y LGT WAS TOLD TO GO AROUND. I TOLD TWR I/WE WERE CLRED POS AND HOLD. THEY SAID THAT WE WEREN'T.

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.