Narrative:

While in taxi to depart from xyz, our flight was told to taxi to runway 19R via txwys B, M, and east, with no other restrs. As captain, I heard the instructions and repeated them to the first officer. However, after turning onto taxiway M, we finished the before takeoff checklist, cleared ourselves visually left and right, and crossed runway 19R on our way to runway 25L (instead of making the left turn up taxiway east for the correct runway). The controller noticed our mistake and informed us to continue straight ahead for a departure on runway 25L. Any number of changes could have prevented this occurrence. 1) either one of the flight crew noticing the mistake as we started to clear ourselves across runway 19R. 2) slightly different taxi route for runway 19R (txwys B, G, and east) so as to avoid taxiway M which led to the other active runway for the day (runway 25L). 3) not using 2 different directional runways for arrival and departure (we landed on runway 25L 30 mins earlier). 4) if we had landed on runway 19R we would have been in the mindset to depart on the same runway. However we landed on runway 25L. Supplemental information from acn 451920: in discussing our error, the captain said he was distraction as I repeated taxi instructions as we were being marshalled out of the gate. Since we just previously landed on runway 25L he was under the impression we were to taxi to runway 25L. As we were taxiing, I just completed reading a checklist as we taxied onto the runway. The captain said clear left, and just then I looked up to clear the right side when I realized we were on the runway. We exited the runway and luckily there was no traffic conflicts.

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Original NASA ASRS Text

Title: ACR TAXIES ACROSS ACTIVE RWY WITHOUT CLRNC.

Narrative: WHILE IN TAXI TO DEPART FROM XYZ, OUR FLT WAS TOLD TO TAXI TO RWY 19R VIA TXWYS B, M, AND E, WITH NO OTHER RESTRS. AS CAPT, I HEARD THE INSTRUCTIONS AND REPEATED THEM TO THE FO. HOWEVER, AFTER TURNING ONTO TXWY M, WE FINISHED THE BEFORE TKOF CHKLIST, CLRED OURSELVES VISUALLY L AND R, AND CROSSED RWY 19R ON OUR WAY TO RWY 25L (INSTEAD OF MAKING THE L TURN UP TXWY E FOR THE CORRECT RWY). THE CTLR NOTICED OUR MISTAKE AND INFORMED US TO CONTINUE STRAIGHT AHEAD FOR A DEP ON RWY 25L. ANY NUMBER OF CHANGES COULD HAVE PREVENTED THIS OCCURRENCE. 1) EITHER ONE OF THE FLC NOTICING THE MISTAKE AS WE STARTED TO CLR OURSELVES ACROSS RWY 19R. 2) SLIGHTLY DIFFERENT TAXI RTE FOR RWY 19R (TXWYS B, G, AND E) SO AS TO AVOID TXWY M WHICH LED TO THE OTHER ACTIVE RWY FOR THE DAY (RWY 25L). 3) NOT USING 2 DIFFERENT DIRECTIONAL RWYS FOR ARR AND DEP (WE LANDED ON RWY 25L 30 MINS EARLIER). 4) IF WE HAD LANDED ON RWY 19R WE WOULD HAVE BEEN IN THE MINDSET TO DEPART ON THE SAME RWY. HOWEVER WE LANDED ON RWY 25L. SUPPLEMENTAL INFO FROM ACN 451920: IN DISCUSSING OUR ERROR, THE CAPT SAID HE WAS DISTR AS I REPEATED TAXI INSTRUCTIONS AS WE WERE BEING MARSHALLED OUT OF THE GATE. SINCE WE JUST PREVIOUSLY LANDED ON RWY 25L HE WAS UNDER THE IMPRESSION WE WERE TO TAXI TO RWY 25L. AS WE WERE TAXIING, I JUST COMPLETED READING A CHKLIST AS WE TAXIED ONTO THE RWY. THE CAPT SAID CLR L, AND JUST THEN I LOOKED UP TO CLR THE R SIDE WHEN I REALIZED WE WERE ON THE RWY. WE EXITED THE RWY AND LUCKILY THERE WAS NO TFC CONFLICTS.

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.