Date: 201201
Local time of day: 1801-2400
Location: ZZZ.Airport, US
Light: Night
Aircraft: Commercial Fixed Wing
Operator: Air Carrier
Operating under: Part 121
Mission: Passenger
Flight phase: Parked
Aircraft component: Flight Data Recording
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Lead Technician
Reporter qualification: Maintenance Powerplant; Maintenance Airframe
Human factors: Confusion; Situational Awareness; Communication Breakdown
Anomaly: Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Maintenance
When detected: Other Paperwork Audit
Result: General Maintenance Action
Contributing factors: Procedure; Company Policy; Human Factors; Incorrect / Not Installed / Unavailable Part; Logbook Entry; Manuals; Chart Or Publication; Aircraft
Primary problem: Incorrect / Not Installed / Unavailable Part

Narrative: March 2012; an origional fleet aircraft arrived at ZZZ Station. Due to a long history of Flight Data Recorder (FDR) status messages and related system problems; the Digital Flight Data Acquisition Unit (DFDAU) was requested to be replaced by Maintenance Control; and stated such in the Open Maintenance Item list; along with the Part Number (P/N) to be installed. I had arrived on shift one hour earlier. I verified the [DFDAU] part had been ordered for the aircraft by checking our storage cart where it was located. After replacing the part and performing the System Checkout per the Aircraft Maintenance Manual (AMM); I cleared the maintenance item and released the aircraft for service. I failed to verify the [DFDAU] part ordered was the correct Part Number Effectivity for that specific aircraft. As it turned out; the part I installed was the correct part number for our merger acquired aircraft; but not for our Air Carrier's original aircraft. The Line Replaceable Unit (LRU) was the same in design; and fit the [electrical] rack position where it was located; it just wasn't the correct 'effectivity' per the Illustrated Parts Catalog (IPC). This event happened about the same time when much confusion existed during the crossover [blending] of two fleet's Parts Availability System programs. During our daily briefings; the Technicians were literally told one day that all parts between both fleets [merger fleet and our fleet] were interchangeable; than the next day told that they were not. Finally it was settled that confirmation of the correct part number could only be accomplished through the IPC; and that each Technician must verify that each part installed was 'effective' to the equipment it was being installed upon through the IPC only. I failed to do that in this scenario; instead I relied on [the Open Maintenance Item] pre-printed list; stating the part needed being accurate. Better research and scrutinizing of a part and it's 'effectivity' would help alleviate; or eliminate this problem from happening again.




Synopsis: A Line Mechanic was informed a Digital Flight Data Acquisition Unit (DFDAU) he installed on one of their Air Carrier's original aircraft was only 'Effective' on the merger acquired aircraft. Contributing to the event was the confusion caused by the crossover (blending) of the two Air Carrier's Parts Availability System programs.