Narrative:

Flight took off from msp en route to dfw. Right after level off at FL310 and reduction from climb to cruise power, a rumble was heard from the rear of the aircraft, accompanied by a fluctuation of the #2 engine instruments, including a drop in fuel flow from 3000 to 2000 pounds per hour for a moment. Then all indications were normal. A similar rumble was heard about 1-2 mins later, and the #2 engine was brought to idle power. All engine indications remained normal for the remainder of the flight, and no abnormal sounds or vibrations were noticed thereafter. A return to msp was initiated after consulting by radio with dispatch and maintenance control. An emergency was declared with ATC. Approximately 2500 pounds of fuel was jettisoned prior to landing to reduce to under maximum landing weight. No further problems were encountered. A maintenance examination of the #2 engine revealed that a piece of the upper VHF antenna separated and was ingested in the engine.

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Original NASA ASRS Text

Title: ACR ENRTE TO DFW LEVEL FL310 NOTED DROP IN FUEL FLOW #2 ENG AND A RUMBLE. ALL OTHER INDICATIONS NORMAL. SIMILAR RUMBLE HEARD 1-2 MINS LATER AND #2 THRUST LEVER REDUCED TO IDLE. ALL INDICATIONS NORMAL. COM WITH DISPATCH AGREED WITH RETURN TO MSP. 2500 LBS FUEL DUMPED, EMER DECLARED AND NORMAL LNDG MSP. MAINT FOUND PART OF VHF ANTENNAE HAD BROKEN AND GONE THROUGH THE #2 ENG.

Narrative: FLT TOOK OFF FROM MSP ENRTE TO DFW. RIGHT AFTER LEVEL OFF AT FL310 AND REDUCTION FROM CLB TO CRUISE PWR, A RUMBLE WAS HEARD FROM THE REAR OF THE ACFT, ACCOMPANIED BY A FLUCTUATION OF THE #2 ENG INSTS, INCLUDING A DROP IN FUEL FLOW FROM 3000 TO 2000 LBS PER HR FOR A MOMENT. THEN ALL INDICATIONS WERE NORMAL. A SIMILAR RUMBLE WAS HEARD ABOUT 1-2 MINS LATER, AND THE #2 ENG WAS BROUGHT TO IDLE PWR. ALL ENG INDICATIONS REMAINED NORMAL FOR THE REMAINDER OF THE FLT, AND NO ABNORMAL SOUNDS OR VIBRATIONS WERE NOTICED THEREAFTER. A RETURN TO MSP WAS INITIATED AFTER CONSULTING BY RADIO WITH DISPATCH AND MAINT CTL. AN EMER WAS DECLARED WITH ATC. APPROX 2500 LBS OF FUEL WAS JETTISONED PRIOR TO LNDG TO REDUCE TO UNDER MAX LNDG WT. NO FURTHER PROBS WERE ENCOUNTERED. A MAINT EXAMINATION OF THE #2 ENG REVEALED THAT A PIECE OF THE UPPER VHF ANTENNA SEPARATED AND WAS INGESTED IN THE ENG.

Data retrieved from NASA's ASRS site as of July 2007 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.