Narrative:

I was flying from mdt to fwa. The flight began in VFR conditions out of mdt. When I departed, the reported ceiling in mdt was 7500 ft, visibility was 5-10 mi. I climbed to 6000 ft and began my westward flight. As the flight progressed, the ceiling began to come down and visibility decreased. When I got over the allegheny mountains, I began experiencing steady light snow. I reported this condition to center. They asked if I was experiencing any ice formation on the plane. I reported that I was not. About 2 hours into the flight, I began considering returning to mdt. The conditions were getting more marginal and the WX along the route was reported as less appealing than earlier forecasts indicated. I was about to make a 180 degree turn to return to mdt when the engine faltered and then stopped. I immediately informed center, turned on the fuel pump, made the mixture rich, and engaged alternate air. The engine restarted. However, since I was unsure of the source of the problem and the engine seemed a little rough, I chose to declare an emergency and asked for vectors to the nearest airport with a precision approach, rather than turn around and attempt a flight across the mountains again to mdt. Center vectored me to the ILS at a nearby airport. Frankly, I have forgotten the name of the airport. Visibility at the airport was about 1/2 mi. As it turned out, I missed the approach. I then requested vectors to an airport with better visibility and ceiling. Center handed me off to pittsburgh approach, who vectored me to ILS for runway 28 at allegheny county. I landed there successfully. However, in the descent through the clouds, I picked up about 1/4 inch of rime ice on the leading edge of the wings. On the ground, I had the FBO check the engine. They found the air filter clogged with ice. I didn't know if that caused the initial problem or was picked up on the descent. The next day, I continued the flight in VFR conditions to fwa and from there, on to my home base. During the run-up at fwa, the left magneto was rough and showed a decrease in RPM of over 200 RPM. I returned to the ramp and had maintenance check it out. They pulled, cleaned, and re-gapped all the plugs and removed some deposits on the leads. After that, the engine ran smoothly and I completed the flight with no further incidents.

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Original NASA ASRS Text

Title: IFR ENRTE PA28 ENCOUNTERS ADVERSE WX CONDITIONS, DECLARES AN EMER WITH ZOB, IS UNABLE TO MAKE A LNDG AT NEAREST ARPT DUE TO WX, HDOF TO PIT APCH WHERE BETTER WX CONDITIONS ALLOW A LNDG.

Narrative: I WAS FLYING FROM MDT TO FWA. THE FLT BEGAN IN VFR CONDITIONS OUT OF MDT. WHEN I DEPARTED, THE RPTED CEILING IN MDT WAS 7500 FT, VISIBILITY WAS 5-10 MI. I CLBED TO 6000 FT AND BEGAN MY WESTWARD FLT. AS THE FLT PROGRESSED, THE CEILING BEGAN TO COME DOWN AND VISIBILITY DECREASED. WHEN I GOT OVER THE ALLEGHENY MOUNTAINS, I BEGAN EXPERIENCING STEADY LIGHT SNOW. I RPTED THIS CONDITION TO CTR. THEY ASKED IF I WAS EXPERIENCING ANY ICE FORMATION ON THE PLANE. I RPTED THAT I WAS NOT. ABOUT 2 HRS INTO THE FLT, I BEGAN CONSIDERING RETURNING TO MDT. THE CONDITIONS WERE GETTING MORE MARGINAL AND THE WX ALONG THE RTE WAS RPTED AS LESS APPEALING THAN EARLIER FORECASTS INDICATED. I WAS ABOUT TO MAKE A 180 DEG TURN TO RETURN TO MDT WHEN THE ENG FALTERED AND THEN STOPPED. I IMMEDIATELY INFORMED CTR, TURNED ON THE FUEL PUMP, MADE THE MIXTURE RICH, AND ENGAGED ALTERNATE AIR. THE ENG RESTARTED. HOWEVER, SINCE I WAS UNSURE OF THE SOURCE OF THE PROB AND THE ENG SEEMED A LITTLE ROUGH, I CHOSE TO DECLARE AN EMER AND ASKED FOR VECTORS TO THE NEAREST ARPT WITH A PRECISION APCH, RATHER THAN TURN AROUND AND ATTEMPT A FLT ACROSS THE MOUNTAINS AGAIN TO MDT. CTR VECTORED ME TO THE ILS AT A NEARBY ARPT. FRANKLY, I HAVE FORGOTTEN THE NAME OF THE ARPT. VISIBILITY AT THE ARPT WAS ABOUT 1/2 MI. AS IT TURNED OUT, I MISSED THE APCH. I THEN REQUESTED VECTORS TO AN ARPT WITH BETTER VISIBILITY AND CEILING. CTR HANDED ME OFF TO PITTSBURGH APCH, WHO VECTORED ME TO ILS FOR RWY 28 AT ALLEGHENY COUNTY. I LANDED THERE SUCCESSFULLY. HOWEVER, IN THE DSCNT THROUGH THE CLOUDS, I PICKED UP ABOUT 1/4 INCH OF RIME ICE ON THE LEADING EDGE OF THE WINGS. ON THE GND, I HAD THE FBO CHK THE ENG. THEY FOUND THE AIR FILTER CLOGGED WITH ICE. I DIDN'T KNOW IF THAT CAUSED THE INITIAL PROB OR WAS PICKED UP ON THE DSCNT. THE NEXT DAY, I CONTINUED THE FLT IN VFR CONDITIONS TO FWA AND FROM THERE, ON TO MY HOME BASE. DURING THE RUN-UP AT FWA, THE L MAGNETO WAS ROUGH AND SHOWED A DECREASE IN RPM OF OVER 200 RPM. I RETURNED TO THE RAMP AND HAD MAINT CHK IT OUT. THEY PULLED, CLEANED, AND RE-GAPPED ALL THE PLUGS AND REMOVED SOME DEPOSITS ON THE LEADS. AFTER THAT, THE ENG RAN SMOOTHLY AND I COMPLETED THE FLT WITH NO FURTHER INCIDENTS.

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.