Narrative:

On aug/xa/01, aircraft X and aircraft Y departed ZZZ. During the night, a local mechanic had performed routine maintenance on each aircraft and had taken both maintenance log cans inside the operations area to fill out the paperwork. Upon returning, the mechanic mistakenly put the wrong log can into the wrong aircraft. The mistake wasn't noticed for hours. By the time it was discovered several flight hours had been flown, and 7 crew members between the 2 aircraft had not noticed the mix-up. Although no incident occurred, it left the airline, the crew members, and the passenger in potential danger due to unknown open write-ups (there were none), unknown deferrals (there were none), and a potentially overweight takeoff (the airline operates both 51000 pounds and 53000 pound aircraft, although no takeoffs over 51000 pounds were made by either aircraft). Contributing factors included the incorrect disposition of documents by the mechanic, lack of a procedure to encourage pilots to check their aircraft number against the log can, and lack of knowledge by the pilots that such an event could occur, leaving no realistic reason to take the time to check for it. All pilots involved in the incident have conferred with and encouraged the company to publish a requirement for flcs to xchk aircraft numbers, as well as to publicize the incident in internal company documents to raise awareness.

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Original NASA ASRS Text

Title: 2 CANADAIR CL65 ACFT WERE DISPATCHED IN NON COMPLIANCE WITH THE WRONG LOGBOOKS BOARDED.

Narrative: ON AUG/XA/01, ACFT X AND ACFT Y DEPARTED ZZZ. DURING THE NIGHT, A LCL MECH HAD PERFORMED ROUTINE MAINT ON EACH ACFT AND HAD TAKEN BOTH MAINT LOG CANS INSIDE THE OPS AREA TO FILL OUT THE PAPERWORK. UPON RETURNING, THE MECH MISTAKENLY PUT THE WRONG LOG CAN INTO THE WRONG ACFT. THE MISTAKE WASN'T NOTICED FOR HOURS. BY THE TIME IT WAS DISCOVERED SEVERAL FLT HOURS HAD BEEN FLOWN, AND 7 CREW MEMBERS BTWN THE 2 ACFT HAD NOT NOTICED THE MIX-UP. ALTHOUGH NO INCIDENT OCCURRED, IT LEFT THE AIRLINE, THE CREW MEMBERS, AND THE PAX IN POTENTIAL DANGER DUE TO UNKNOWN OPEN WRITE-UPS (THERE WERE NONE), UNKNOWN DEFERRALS (THERE WERE NONE), AND A POTENTIALLY OVERWT TKOF (THE AIRLINE OPERATES BOTH 51000 LBS AND 53000 LB ACFT, ALTHOUGH NO TKOFS OVER 51000 LBS WERE MADE BY EITHER ACFT). CONTRIBUTING FACTORS INCLUDED THE INCORRECT DISPOSITION OF DOCUMENTS BY THE MECH, LACK OF A PROC TO ENCOURAGE PLTS TO CHK THEIR ACFT NUMBER AGAINST THE LOG CAN, AND LACK OF KNOWLEDGE BY THE PLTS THAT SUCH AN EVENT COULD OCCUR, LEAVING NO REALISTIC REASON TO TAKE THE TIME TO CHK FOR IT. ALL PLTS INVOLVED IN THE INCIDENT HAVE CONFERRED WITH AND ENCOURAGED THE COMPANY TO PUBLISH A REQUIREMENT FOR FLCS TO XCHK ACFT NUMBERS, AS WELL AS TO PUBLICIZE THE INCIDENT IN INTERNAL COMPANY DOCUMENTS TO RAISE AWARENESS.

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.