Date: 201401
Local time of day: 1201-1800
Location: ZZZ.Airport, US
Flight conditions: VMC
Weather elements / visibility: Haze / Smoke
Light: Daylight
Aircraft: MD-88
Operator: Air Carrier
Operating under: Part 121
Mission: Passenger
Flight phase: Climb
Airspace: Class D ZZZ
ATC / advisory: Tower ZZZ
Aircraft component: Powerplant Fuel Control Unit
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Communication Breakdown; Confusion
Anomaly: Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter Other / Unknown
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Inflight Shutdown; Flight Crew Returned To Departure Airport; Flight Crew Overcame Equipment Problem; General Maintenance Action; General Declared Emergency
Contributing factors: Procedure; Manuals; Human Factors; Aircraft
Primary problem: Human Factors

Narrative: My First Officer and I pushed off the gate after a 43-minute turn and were pushed back for deicing. Once deicing was complete; we were cleared to taxi to the runway for departure. Cleared for takeoff; I performed the 15-second engine run for ice clearing and departed! We were cleared on course; so at 400 FT AGL we made the right turn and selected NAV. The First Officer contacted Departure Control and we were given climb to 10;000 FT. Climbing through 3;000 FT; I felt the airplane yaw and soon thereafter we heard the Landing Gear Warning come alive! We thought we had a gear malfunction so First Officer cycled the gear and that's when I noticed the Automatic Reserve Thrust (ART) had fired! The landing gear was fine! I then saw the Right Engine gages showed the N1; EPR; N2 and temperature indicators flashing! At this time I noticed the throttles were at idle! I asked First Officer if we had an engine failure... he said 'No'! I then realized we did have a failure but in overboost! We had no control of the Right Engine and it was overboosting badly! We elected to shut it down immediately; we went through the motions of safely securing the good engine fuel control and shut down the Right Engine. First Officer also performed the Immediate Action for the engine as well! This action did us no good! The yawing sensation was dramatic but controllable. I then brought up the left engine power; trimmed out the aircraft and received vectors for return to [our departure airport]. We completed the Shutdown Checklist followed by the Single Engine Landing Checklist. I made a short but direct PA to the passengers. We landed on the runway with no further incident. I did declare an emergency; therefore the fire trucks were waiting for us! Once clear of the runway I asked the Tower to check with Emergency [Crew] for evidence of fire or damage on the Right Engine. Tower confirmed we had no apparent damage or fire. At no time in the flight did we receive any fire warnings on the Right Engine!This emergency was quite an eye opener from a pilot standpoint and an operational/company standpoint! First Officer and I went through the checklists as quickly as we could in trying to save this engine. There is no way would could have been faster in my opinion! This failure was a reverse failure in mine and the First Officer's experience! Once Contract Maintenance arrived and started troubleshooting; they found a very disturbing issue! The linkage on the Right Engine Fuel Control Unit (FCU) [had] disengaged because there was NO SAFETY WIRING/COTTER KEY INSTALLED! Upon further examination of the FCU; the linkage next to the failed [disconnected] linkage had NO SAFETY WIRING/COTTER KEY installed either! The MD-88 had just been returned to service from checks! Do we need to exam their maintenance practices? From a training perspective; would it be possible to put this scenario in as well? Right Engine Fuel Control Unit (FCU) failed; Right Engine went to 100%+ uncontrolled.

Callback: Reporter stated they were taking the MD-88 aircraft on its first revenue flight since it was released from a C-Check at a Contract Maintenance Repair Station. When he moved the engine throttles back while climbing through 3;000 FT; there was no response from the Right Engine; which had gone into overboost; Automatic Reserve Thrust (ART); increasing from normal takeoff power to max. The ARTs light did illuminate. Engines are PW JT-8-219's. He believes the Right Engine went into overboost when the throttles were reduced because the ART's sensed the Left Engine had failed when the Right Engine remained at takeoff power after the throttle linkage to the Fuel Control Unit (FCU) had disconnected. The Right Engine did overtemp and overboost beyond 101%. There was discussion about using their experience in training; but nothing definite yet.



Synopsis: Captain reported the Right Engine on an MD-88 aircraft overboosted while climbing through 3;000 FT. The Automatic Reserve Thrust (ARTs) had activated; ARTs light had illuminated; but the Right Engine would not respond to throttle movement. Emergency declared. Throttle linkage had separated at the Fuel Control Unit (FCU).