Narrative:

We departed ZZZ1 for our destination of ZZZ2 at approximately XA15 local time on a part 91 IFR flight. I was sitting in the right seat performing the non-flying duties during all portions of the flight; (radio communication; GPS; engine monitoring). The PIC was an ATP multi-engine rated pilot with single commercial privileges instrument ratings; he was trained and qualified for a part 91 flight in the PA46. A little after 2 hours into the flight we experienced 4-5 engine fluctuations similar to slight water contamination through the fuel system. Similar fluctuations were experienced on previous flts but never more than 2 occurrences and never in close succession. The initial problems were brought to the attention of our maintenance personnel who during the annual inspection in jul 2006 deemed the aircraft airworthy and stated that they could not find or replicate the problems we had experienced. They stated the problem might have been slight fuel contamination and that it was normal. These latest fluctuations occurred 2 hours into the flight which made the initial claim of fuel contamination appear inaccurate. As the pilot operating the radios I notified ATC we would like the location of the nearest VFR airport and advised we were experiencing engine fluctuations. We then asked for permission to deviate to ZZZ for which the controller provided the current WX. We also advised the controller that we intended to declare an emergency if the fluctuations continued. At that time we experienced another engine fluctuation and I along with the PIC agreed to declare an emergency. We descended and landed uneventfully at ZZZ. After landing I called the local FSS to cancel our IFR flight plan and advised we have landed without incident. I remained on the phone until I received a confirmation from the briefer that the flight was canceled. We have also strained the fuel from the aircraft upon arrival to check for possible water or debris contamination. The fuel samples drained showed no contamination and were dry. After landing we proceeded to investigate our situation with our primary maintenance facility. We have also contacted a malibu pilots association; and other a&P mechanics for second opinion and advice. Once we ruled out fuel contamination our focus turned to the pressurized magnetos. Every mechanic we have interviewed stated that the magnetos are known to cause the problems we have experienced but the faults do not render the aircraft unairworthy and a flight to the nearest maintenance shop will be safe and within part 91 regulations. Since we received similar advice from several reputable sources we filed a flight plan direct to our maintenance facility. Our extensive ground run up testing to simulate all forms of flight did not provide any engine readings which would indicate a problem with the engine; fuel system nor the magnetos. All indications were within the poh specifications for preflight run up. We then decided to depart ZZZ and circle the airport to pick up our IFR clearance. Upon climb out both I and the other pilot felt the engine slightly fluctuate; at that point the decision was made to return to the airport and have maintenance examine the aircraft before any subsequent flts. 7 days after our occurrence the dispatched mechanics received a call from the FAA that after a review of the declared emergency records; there was a discrepancy with the registration of the aircraft and the onboard registration card was expired. Upon notification; we immediately contacted the FAA aircraft records office in oklahoma and inquired about the allegation as we have not received any notification of registration problems. An inquiry to the seller around the time of our annual inspection indicated that these things take time and no further follow up was conducted neither by us nor the seller. Supplemental information from acn 714478: we arranged a maintenance field trip to temporarily repair the aircraft and fly it to ZZZ1 for permanent repair. Upon arrival of the 2 mechanics the FAA called the FBO inquiring of the incident (following up). A few items I would like to note. Several maintenance facilities including our local (primary) facility advised that the fluctuations we were experiencing were normal fluctuations; which reflected normal magneto wear and tear. They indicated that 9 one time flts to conduct a repair was acceptable and legal.

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Original NASA ASRS Text

Title: A PA46 CREW DECLARED AN EMER AND DIVERTED FOLLOWING ENG FLUCTUATIONS.

Narrative: WE DEPARTED ZZZ1 FOR OUR DEST OF ZZZ2 AT APPROX XA15 LCL TIME ON A PART 91 IFR FLT. I WAS SITTING IN THE R SEAT PERFORMING THE NON-FLYING DUTIES DURING ALL PORTIONS OF THE FLT; (RADIO COM; GPS; ENG MONITORING). THE PIC WAS AN ATP MULTI-ENG RATED PLT WITH SINGLE COMMERCIAL PRIVILEGES INST RATINGS; HE WAS TRAINED AND QUALIFIED FOR A PART 91 FLT IN THE PA46. A LITTLE AFTER 2 HRS INTO THE FLT WE EXPERIENCED 4-5 ENG FLUCTUATIONS SIMILAR TO SLIGHT WATER CONTAMINATION THROUGH THE FUEL SYS. SIMILAR FLUCTUATIONS WERE EXPERIENCED ON PREVIOUS FLTS BUT NEVER MORE THAN 2 OCCURRENCES AND NEVER IN CLOSE SUCCESSION. THE INITIAL PROBS WERE BROUGHT TO THE ATTN OF OUR MAINT PERSONNEL WHO DURING THE ANNUAL INSPECTION IN JUL 2006 DEEMED THE ACFT AIRWORTHY AND STATED THAT THEY COULD NOT FIND OR REPLICATE THE PROBS WE HAD EXPERIENCED. THEY STATED THE PROB MIGHT HAVE BEEN SLIGHT FUEL CONTAMINATION AND THAT IT WAS NORMAL. THESE LATEST FLUCTUATIONS OCCURRED 2 HRS INTO THE FLT WHICH MADE THE INITIAL CLAIM OF FUEL CONTAMINATION APPEAR INACCURATE. AS THE PLT OPERATING THE RADIOS I NOTIFIED ATC WE WOULD LIKE THE LOCATION OF THE NEAREST VFR ARPT AND ADVISED WE WERE EXPERIENCING ENG FLUCTUATIONS. WE THEN ASKED FOR PERMISSION TO DEVIATE TO ZZZ FOR WHICH THE CTLR PROVIDED THE CURRENT WX. WE ALSO ADVISED THE CTLR THAT WE INTENDED TO DECLARE AN EMER IF THE FLUCTUATIONS CONTINUED. AT THAT TIME WE EXPERIENCED ANOTHER ENG FLUCTUATION AND I ALONG WITH THE PIC AGREED TO DECLARE AN EMER. WE DSNDED AND LANDED UNEVENTFULLY AT ZZZ. AFTER LNDG I CALLED THE LCL FSS TO CANCEL OUR IFR FLT PLAN AND ADVISED WE HAVE LANDED WITHOUT INCIDENT. I REMAINED ON THE PHONE UNTIL I RECEIVED A CONFIRMATION FROM THE BRIEFER THAT THE FLT WAS CANCELED. WE HAVE ALSO STRAINED THE FUEL FROM THE ACFT UPON ARR TO CHK FOR POSSIBLE WATER OR DEBRIS CONTAMINATION. THE FUEL SAMPLES DRAINED SHOWED NO CONTAMINATION AND WERE DRY. AFTER LNDG WE PROCEEDED TO INVESTIGATE OUR SITUATION WITH OUR PRIMARY MAINT FACILITY. WE HAVE ALSO CONTACTED A MALIBU PLTS ASSOCIATION; AND OTHER A&P MECHS FOR SECOND OPINION AND ADVICE. ONCE WE RULED OUT FUEL CONTAMINATION OUR FOCUS TURNED TO THE PRESSURIZED MAGNETOS. EVERY MECH WE HAVE INTERVIEWED STATED THAT THE MAGNETOS ARE KNOWN TO CAUSE THE PROBS WE HAVE EXPERIENCED BUT THE FAULTS DO NOT RENDER THE ACFT UNAIRWORTHY AND A FLT TO THE NEAREST MAINT SHOP WILL BE SAFE AND WITHIN PART 91 REGS. SINCE WE RECEIVED SIMILAR ADVICE FROM SEVERAL REPUTABLE SOURCES WE FILED A FLT PLAN DIRECT TO OUR MAINT FACILITY. OUR EXTENSIVE GND RUN UP TESTING TO SIMULATE ALL FORMS OF FLT DID NOT PROVIDE ANY ENG READINGS WHICH WOULD INDICATE A PROB WITH THE ENG; FUEL SYS NOR THE MAGNETOS. ALL INDICATIONS WERE WITHIN THE POH SPECS FOR PREFLT RUN UP. WE THEN DECIDED TO DEPART ZZZ AND CIRCLE THE ARPT TO PICK UP OUR IFR CLRNC. UPON CLBOUT BOTH I AND THE OTHER PLT FELT THE ENG SLIGHTLY FLUCTUATE; AT THAT POINT THE DECISION WAS MADE TO RETURN TO THE ARPT AND HAVE MAINT EXAMINE THE ACFT BEFORE ANY SUBSEQUENT FLTS. 7 DAYS AFTER OUR OCCURRENCE THE DISPATCHED MECHS RECEIVED A CALL FROM THE FAA THAT AFTER A REVIEW OF THE DECLARED EMER RECORDS; THERE WAS A DISCREPANCY WITH THE REGISTRATION OF THE ACFT AND THE ONBOARD REGISTRATION CARD WAS EXPIRED. UPON NOTIFICATION; WE IMMEDIATELY CONTACTED THE FAA ACFT RECORDS OFFICE IN OKLAHOMA AND INQUIRED ABOUT THE ALLEGATION AS WE HAVE NOT RECEIVED ANY NOTIFICATION OF REGISTRATION PROBS. AN INQUIRY TO THE SELLER AROUND THE TIME OF OUR ANNUAL INSPECTION INDICATED THAT THESE THINGS TAKE TIME AND NO FURTHER FOLLOW UP WAS CONDUCTED NEITHER BY US NOR THE SELLER. SUPPLEMENTAL INFO FROM ACN 714478: WE ARRANGED A MAINT FIELD TRIP TO TEMPORARILY REPAIR THE ACFT AND FLY IT TO ZZZ1 FOR PERMANENT REPAIR. UPON ARR OF THE 2 MECHS THE FAA CALLED THE FBO INQUIRING OF THE INCIDENT (FOLLOWING UP). A FEW ITEMS I WOULD LIKE TO NOTE. SEVERAL MAINT FACILITIES INCLUDING OUR LCL (PRIMARY) FACILITY ADVISED THAT THE FLUCTUATIONS WE WERE EXPERIENCING WERE NORMAL FLUCTUATIONS; WHICH REFLECTED NORMAL MAGNETO WEAR AND TEAR. THEY INDICATED THAT 9 ONE TIME FLTS TO CONDUCT A REPAIR WAS ACCEPTABLE AND LEGAL.

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