Date: 201204
Local time of day: 1801-2400
Location: ZZZ.ARTCC, US
Flight conditions: VMC
Light: Night
Aircraft: A321
Operator: Air Carrier
Operating under: Part 121
Mission: Passenger
Flight phase: Cruise
Airspace: Class A ZZZ
ATC / advisory: Center ZZZ
Aircraft component: Horizontal Stabilizer Trim
Component problem: Failed
Reporter organization: Air Carrier
Reporter function: Pilot Not Flying; First Officer
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Second reporter function: Captain; Pilot Flying
Anomaly: Aircraft Equipment Problem Critical
Detector: Automation Aircraft Other Automation; Person Flight Crew
When detected: In-flight
Result: Flight Crew Diverted; Flight Crew Landed in Emergency Condition; General Declared Emergency; General Maintenance Action
Contributing factors: Aircraft
Primary problem: Aircraft

Narrative: In normal cruse at 34;000 FT on autopilot 1; autopilot 1 disengaged by itself. Captain tried to re-engage autopilot but neither 1 or 2 would engage for very long. [We] reviewed ECAM pages to see if anything appeared out of normal parameters. Status messages were sporadically displaying 'CAT III Dual';' A/P 1 & 2' and then 'normal' messages. About the same time we felt a sudden and continuous moderate vibration that lasted about 10-15 seconds throughout the airframe. Shortly after we received ECAM 'ELAC 2 PITCH FAULT' this was closely followed by an ECAM 'ELAC 1 PITCH FAULT' and a 'STABILIZER JAM' warning; aircraft reverted to Alternate Law. The Captain; who was hand flying; noted that in level flight the airplane had begun to abruptly pitch up with uncommanded nose up trim approximately into a 200 FPM climb before recovering. While complying with the ECAM procedures; we experienced a second sustained airframe vibration. Declared an emergency and diverted to the nearest suitable airport in point of time. Sent a quick ACARS message that we were diverting due to multiple flight control failures and tried to raise station ops on the radio but they were closed up for the night. As we were descending in a turn for the field we felt one more vibration. After gear extension; landed in direct law uneventfully. [We] called Dispatch ASAP after we were safely stopped.

Callback: This reporter was not informed what component caused the flight control issues but the aircraft did have a history of ELAC failures; although without any associated faults. The vibrations felt were significant enough to cause the flight attendants to call the cockpit.

Second narrative: Established in cruse altitude at FL340 we lost autopilot 1 and 2; unable to re-engage. Shortly thereafter we experienced moderate airframe vibration lasting about 15 seconds. Soon after we had multiple failures of ELAC 1 and 2 followed by ECAM Message for Stabilizer Jam; experienced two more airframe vibration events lasting 10-15 seconds each. Aircraft reverted to Alternate Law; Declared Emergency and diverted to nearest suitable airport in point of time. After gear extension; aircraft reverted to Direct Law Landing - was uneventful. Multiple failures of redundant systems.


Synopsis: A321 flight crew describes an autopilot disengagement and an ECAM messages for ELAC 1 and 2 faults and a stabilizer jam at FL340. Moderate vibration is felt through the airframe lasting 10 to 15 seconds just prior to the messages. An emergency is declared and flight diverts to the nearest suitable airport; landing in Direct Law after gear extension.