Narrative:

Myself and flight crew reported to lse operations on time. Flight attendants boarded the aircraft, first officer performed walkaround. I checked WX and then reviewed and signed dispatch release. I then boarded the aircraft via the jetway, which was the only jetway serving 2 DC9's, one directly behind and nosed into our trailing edge (left wing). All cockpit checks were performed, passenger loaded, and we departed the gate. While taxiing out, we were unable to get our takeoff data via ACARS, because the ACARS unit thought we were flight xyz (we are abc). Assuming the ACARS was faulty, we received our data via radio from lse operations and departed. Approaching msp, we again were unable to receive landing data for flight abc (ACARS still hung up on xyz). At this point we began in-depth troubleshooting and discovered we had aircraft xyzz, and had been dispatched with xxww, which was the aircraft parked behind us in lse. This event occurred because of my failure to compare actual aircraft number to dispatched aircraft number. With the way the aircraft were parked, the one we flew was the only one that could leave the gate and as the only jetway was connected to it I had no reason to suspect it was not our aircraft. It was more logical for me to believe the ACARS was faulty, as this has happened before. In the future, a xchk of dispatch airplane and actual airplane should eliminate a recurrence. Supplemental information from acn 440720: after short rest overnight in lacrosse, wi (5 hours) during a continuous duty overnight, we had a flight release from lse to msp. Lse operations wanted us out early, so after completing our flows and checklists, we started up and taxied out. We were en route to msp when we started receiving ACARS messages that said our flight number did not match that on the release. The crew was fatigued after the short overnight in lse, and in the hurry to get home, forgot to check the numbers carefully.

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Original NASA ASRS Text

Title: A DC9-30 FLC TAKES THE WRONG ACFT FROM LSE TO MSP.

Narrative: MYSELF AND FLC RPTED TO LSE OPS ON TIME. FLT ATTENDANTS BOARDED THE ACFT, FO PERFORMED WALKAROUND. I CHKED WX AND THEN REVIEWED AND SIGNED DISPATCH RELEASE. I THEN BOARDED THE ACFT VIA THE JETWAY, WHICH WAS THE ONLY JETWAY SERVING 2 DC9'S, ONE DIRECTLY BEHIND AND NOSED INTO OUR TRAILING EDGE (L WING). ALL COCKPIT CHKS WERE PERFORMED, PAX LOADED, AND WE DEPARTED THE GATE. WHILE TAXIING OUT, WE WERE UNABLE TO GET OUR TKOF DATA VIA ACARS, BECAUSE THE ACARS UNIT THOUGHT WE WERE FLT XYZ (WE ARE ABC). ASSUMING THE ACARS WAS FAULTY, WE RECEIVED OUR DATA VIA RADIO FROM LSE OPS AND DEPARTED. APCHING MSP, WE AGAIN WERE UNABLE TO RECEIVE LNDG DATA FOR FLT ABC (ACARS STILL HUNG UP ON XYZ). AT THIS POINT WE BEGAN IN-DEPTH TROUBLESHOOTING AND DISCOVERED WE HAD ACFT XYZZ, AND HAD BEEN DISPATCHED WITH XXWW, WHICH WAS THE ACFT PARKED BEHIND US IN LSE. THIS EVENT OCCURRED BECAUSE OF MY FAILURE TO COMPARE ACTUAL ACFT NUMBER TO DISPATCHED ACFT NUMBER. WITH THE WAY THE ACFT WERE PARKED, THE ONE WE FLEW WAS THE ONLY ONE THAT COULD LEAVE THE GATE AND AS THE ONLY JETWAY WAS CONNECTED TO IT I HAD NO REASON TO SUSPECT IT WAS NOT OUR ACFT. IT WAS MORE LOGICAL FOR ME TO BELIEVE THE ACARS WAS FAULTY, AS THIS HAS HAPPENED BEFORE. IN THE FUTURE, A XCHK OF DISPATCH AIRPLANE AND ACTUAL AIRPLANE SHOULD ELIMINATE A RECURRENCE. SUPPLEMENTAL INFO FROM ACN 440720: AFTER SHORT REST OVERNIGHT IN LACROSSE, WI (5 HRS) DURING A CONTINUOUS DUTY OVERNIGHT, WE HAD A FLT RELEASE FROM LSE TO MSP. LSE OPS WANTED US OUT EARLY, SO AFTER COMPLETING OUR FLOWS AND CHKLISTS, WE STARTED UP AND TAXIED OUT. WE WERE ENRTE TO MSP WHEN WE STARTED RECEIVING ACARS MESSAGES THAT SAID OUR FLT NUMBER DID NOT MATCH THAT ON THE RELEASE. THE CREW WAS FATIGUED AFTER THE SHORT OVERNIGHT IN LSE, AND IN THE HURRY TO GET HOME, FORGOT TO CHK THE NUMBERS CAREFULLY.

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.