Narrative:

Aircraft X was the aircraft we had diverted to ZZZ in from ZZZ1 the night before. We had at that time encountered high N1 vibration (6.1 on engine #2) during our go around and subsequent diversion. While it may have been the icing conditions we flew in; we were not sure; and engine #1; which flew in the same conditions; was fine. We wrote it up and the next day found that engine #2 had been inspected; run; and nothing found amiss. During preflight inspection; the first officer spun the engine #2 N1 fan; and noticed a grinding sound. I went down and spun the engine #2 N1; and heard the same sound; like that of gravel in a rotating tin can. We wrote it up. I suspected ice chunks loose in the engine #2 nose cone; though I had no idea how that could happen. With maintenance aboard; we ran the engine; at low power; anti-ice on; until it warmed up. No unusual or abnormal indications were noted; but as the N1 spooled down; maintenance noticed ice pellets being slung from the area of the nose cone. I went down saw them too. The engine was again signed off; and we pushed back for ZZZ. Takeoff was planned for flex of 37 degrees; flaps 2 degrees; engine anti-ice off. When the first officer stood the throttles up and the engines began to spool; engine #2 vibration quickly reached 7. I elected to reject the takeoff and did so according to procedures. Thrust was never fully set; and the speed was very low; I would estimate no more than 50 KTS; though that's a guess. We exited the runway and returned to the gate; leaving both engines running. Engine #2 vibration was normal at idle on the ground. No emergency was declared. Flight was canceled.

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Original NASA ASRS Text

Title: A320 FLIGHT CREW REJECTS TAKEOFF WHEN N1 VIBRATION EXCEEDS LIMITS. CREW HAD PREVIOUS EXPERIENCE WITH THIS AIRCRAFT BUT MAINTENANCE COULD FIND NOTHING WRONG.

Narrative: ACFT X WAS THE ACFT WE HAD DIVERTED TO ZZZ IN FROM ZZZ1 THE NIGHT BEFORE. WE HAD AT THAT TIME ENCOUNTERED HIGH N1 VIBRATION (6.1 ON ENG #2) DURING OUR GAR AND SUBSEQUENT DIVERSION. WHILE IT MAY HAVE BEEN THE ICING CONDITIONS WE FLEW IN; WE WERE NOT SURE; AND ENG #1; WHICH FLEW IN THE SAME CONDITIONS; WAS FINE. WE WROTE IT UP AND THE NEXT DAY FOUND THAT ENG #2 HAD BEEN INSPECTED; RUN; AND NOTHING FOUND AMISS. DURING PREFLT INSPECTION; THE FO SPUN THE ENG #2 N1 FAN; AND NOTICED A GRINDING SOUND. I WENT DOWN AND SPUN THE ENG #2 N1; AND HEARD THE SAME SOUND; LIKE THAT OF GRAVEL IN A ROTATING TIN CAN. WE WROTE IT UP. I SUSPECTED ICE CHUNKS LOOSE IN THE ENG #2 NOSE CONE; THOUGH I HAD NO IDEA HOW THAT COULD HAPPEN. WITH MAINT ABOARD; WE RAN THE ENG; AT LOW PWR; ANTI-ICE ON; UNTIL IT WARMED UP. NO UNUSUAL OR ABNORMAL INDICATIONS WERE NOTED; BUT AS THE N1 SPOOLED DOWN; MAINT NOTICED ICE PELLETS BEING SLUNG FROM THE AREA OF THE NOSE CONE. I WENT DOWN SAW THEM TOO. THE ENG WAS AGAIN SIGNED OFF; AND WE PUSHED BACK FOR ZZZ. TKOF WAS PLANNED FOR FLEX OF 37 DEGS; FLAPS 2 DEGS; ENG ANTI-ICE OFF. WHEN THE FO STOOD THE THROTTLES UP AND THE ENGS BEGAN TO SPOOL; ENG #2 VIBRATION QUICKLY REACHED 7. I ELECTED TO REJECT THE TKOF AND DID SO ACCORDING TO PROCS. THRUST WAS NEVER FULLY SET; AND THE SPD WAS VERY LOW; I WOULD ESTIMATE NO MORE THAN 50 KTS; THOUGH THAT'S A GUESS. WE EXITED THE RWY AND RETURNED TO THE GATE; LEAVING BOTH ENGS RUNNING. ENG #2 VIBRATION WAS NORMAL AT IDLE ON THE GND. NO EMER WAS DECLARED. FLT WAS CANCELED.

Data retrieved from NASA's ASRS site as of May 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.