A B737-300 was dispatched with the incorrect captain's audio panel installed.

Attributes
ACN	646794
Time
Date	200502
Local Time Of Day	0001 To 0600
Place
Locale Reference	airport : zzz.airport
State Reference	US
Aircraft 1
Controlling Facilities	tower : cmh.tower
Operator	common carrier : air carrier
Make Model Name	B737-300
Operating Under FAR Part	Part 121
Flight Phase	ground : maintenance ground : parked
Person 1
Affiliation	company : air carrier
Qualification	technician : airframe technician : powerplant technician : inspection authority technician : fcc
Experience	maintenance avionics : 18 maintenance supervisor : 28
ASRS Report	646794
Events
Anomaly	aircraft equipment problem : critical maintenance problem : improper maintenance maintenance problem : improper documentation non adherence : published procedure non adherence : far
Independent Detector	other flight crewa other flight crewb
Resolutory Action	none taken : detected after the fact
Consequence	other other
Factors
Maintenance	performance deficiency : non compliance with legal requirements performance deficiency : testing performance deficiency : installation
Supplementary
Problem Areas	Chart Or Publication Maintenance Human Performance Aircraft
Primary Problem	Maintenance Human Performance

Narrative:

Pilot reported a bleedover hum in audio system. I checked system (a computer system to verify part number effective for specific aircraft). I took part to plane and installed and checked system -- operation was normal. This happened on feb/wed/05. On feb/mon/05 correct part was installed after a records/logbook check. I had installed the wrong dash number part on aircraft (mpn x-x; the correct part number was x-y). Air carrier has a system that mechanic must check before installing any part on an aircraft. The aircraft involved was aircraft X. I was assigned to work on 2 aircraft that night and helped others with an additional 2 aircraft. I can't remember how I made this mistake; but I remember I checked system so I would know what part to take to the aircraft. I must have typed in the wrong aircraft number either by transposing numbers or typing in one of the other aircraft I worked on that night by mistake. I have no excuses; I just messed up. Work factors were really not an issue; the workload was fairly light and since it was a remain overnight check; there was no time factor involved.

Original NASA ASRS Text

Title: A B737-300 WAS DISPATCHED WITH THE INCORRECT CAPT'S AUDIO PANEL INSTALLED.

Narrative: PLT RPTED A BLEEDOVER HUM IN AUDIO SYS. I CHKED SYS (A COMPUTER SYS TO VERIFY PART NUMBER EFFECTIVE FOR SPECIFIC ACFT). I TOOK PART TO PLANE AND INSTALLED AND CHKED SYS -- OP WAS NORMAL. THIS HAPPENED ON FEB/WED/05. ON FEB/MON/05 CORRECT PART WAS INSTALLED AFTER A RECORDS/LOGBOOK CHK. I HAD INSTALLED THE WRONG DASH NUMBER PART ON ACFT (MPN X-X; THE CORRECT PART NUMBER WAS X-Y). ACR HAS A SYS THAT MECH MUST CHK BEFORE INSTALLING ANY PART ON AN ACFT. THE ACFT INVOLVED WAS ACFT X. I WAS ASSIGNED TO WORK ON 2 ACFT THAT NIGHT AND HELPED OTHERS WITH AN ADDITIONAL 2 ACFT. I CAN'T REMEMBER HOW I MADE THIS MISTAKE; BUT I REMEMBER I CHKED SYS SO I WOULD KNOW WHAT PART TO TAKE TO THE ACFT. I MUST HAVE TYPED IN THE WRONG ACFT NUMBER EITHER BY TRANSPOSING NUMBERS OR TYPING IN ONE OF THE OTHER ACFT I WORKED ON THAT NIGHT BY MISTAKE. I HAVE NO EXCUSES; I JUST MESSED UP. WORK FACTORS WERE REALLY NOT AN ISSUE; THE WORKLOAD WAS FAIRLY LIGHT AND SINCE IT WAS A REMAIN OVERNIGHT CHK; THERE WAS NO TIME FACTOR INVOLVED.

Data retrieved from NASA's ASRS site as of January 2009 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.