MD-11
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Distraction; Situational Awareness; Troubleshooting
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter Weather / Turbulence
Aircraft Equipment Problem Dissipated
Weather; Aircraft
Cruising at Mach .82/FL310; the aircraft entered an area of heavy precipitation. Engine ignition override was on. Crew observed N2 roll back to approximately 35% and received a Level 2 ENG 2 RPM LO. The throttle did not move and all other engine parameters were normal; EGT; oil pressure/temp. There was no yaw. The crew addressed the QRC; but the engine N2 RPM increased back to normal indications before they could run it. The rollback lasted less than 2 minutes. All indications were normal for remainder of the flight. Unknown cause.
MD-11 Second Officer reported encountering heavy precipitation in cruise flight when engine N2 began to roll back with a caution message; leading to no throttle movement.