Narrative:

Aircraft was on an IFR plan from ZZZ2 to ZZZ3 and had descended to 4000 ft MSL. It was VMC with a ceiling of around 5000 ft AGL. At the time; the engine suddenly lost power. It was still running; but the RPM's dropped dramatically. Pilot immediately switched from the right tank to the left tank. From prior experience; switching tanks was normally effective in approximately 5 seconds. However; the engine did not respond to the switch in tanks. Given that the switch in tanks was unsuccessful and that the pilot was uncertain of the cause of the loss of power; pilot switched his transponder to 7700 and contacted approach and declared an emergency and requested vectors to the nearest airport. The ATC controller indicated that ZZZ was 10 mi straight ahead. Given the current altitude; pilot determined that he would likely not be able to glide to the airport; and thus began looking for a field. Pilot was assisted by his passenger; who is also a pilot; and together they located a couple of fields and a dirt road that were almost directly below the aircraft. Pilot then informed ATC that they would not make the airport and that they had located and/or were looking for a field. At some point; ATC asked what the nature of the problem was; and the pilot indicated that it was an engine/power loss problem. Pilot then got himself prepared to make one of the fields; and determined to bring the throttle back and then full forward to determine how much power (if any) he would have available for landing; in case a go around was necessary. When the pilot did this; the engine came back to full power. The pilot waited and maneuvered slightly to see if the engine would remain at full power; and the engine seemed to be performing normally. At that point; the pilot climbed back to 4000 ft MSL(had suffered an altitude loss of between 500-1000 ft) and then informed ATC that the engine seemed to be performing normally; but that he would still want to be vectored to the closest airport. ATC responded that ZZZ was still directly in front of the aircraft and about 8-9 mi away. ATC asked if the pilot was able to maintain altitude. The pilot indicated that he could maintain altitude; but that he wanted to go ahead and land to determine the cause of the problem. Pilot then flew towards ZZZ and ATC informed him that there was 1 aircraft in the pattern; which the pilot saw and then followed towards the runway. Pilot then indicated that he would make the airport and reported that the plane seemed to be acting normally; and ATC gave him a number to call to cancel his IFR plan. Either just before landing; or immediately afterwards; another aircraft contacted the pilot; asked if everything was ok; and then asked if the pilot wanted his IFR plan canceled. Pilot confirmed that he was fine; that the plan could be canceled; and to thank ATC for their help. Upon stopping the engine and inspecting the aircraft; it appeared that the right tank was completely dry; but that the left tank had approximately 10 gallons left. The pilot then topped off the aircraft; started the engine; and then ran it up; switching between both tanks without a problem. Comfortable that the problem was resolved; the pilot then took off VFR and then flew to ZZZ3 and landed without incident. Pilot would indicate that he believes the initial problem was caused by running the right fuel tank dry. Factors contributing to this were the strong headwind and the rather curious routing that ATC gave the aircraft from ZZZ2 to ZZZ3. While the pilot thought he had plenty of fuel in the right tank; the evidence would indicate otherwise. As far as the failure of the tank switch to immediately solve the problem; the pilot is uncertain why this occurred. The pilot has not had any problems switching tanks before or after this incident; so he can only assume perhaps it was something (air or debris in the fuel line.

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Original NASA ASRS Text

Title: BE24 PVT PLT EXPERIENCED LOSS OF PWR AFTER EXHAUSTING FUEL SUPPLY IN R TANK. PWR WAS RESTORED TO ACFT ONCE TANKS WERE SWITCHED AND FUEL FLOW RE-ESTABLISHED.

Narrative: ACFT WAS ON AN IFR PLAN FROM ZZZ2 TO ZZZ3 AND HAD DSNDED TO 4000 FT MSL. IT WAS VMC WITH A CEILING OF AROUND 5000 FT AGL. AT THE TIME; THE ENG SUDDENLY LOST PWR. IT WAS STILL RUNNING; BUT THE RPM'S DROPPED DRAMATICALLY. PLT IMMEDIATELY SWITCHED FROM THE R TANK TO THE L TANK. FROM PRIOR EXPERIENCE; SWITCHING TANKS WAS NORMALLY EFFECTIVE IN APPROX 5 SECONDS. HOWEVER; THE ENG DID NOT RESPOND TO THE SWITCH IN TANKS. GIVEN THAT THE SWITCH IN TANKS WAS UNSUCCESSFUL AND THAT THE PLT WAS UNCERTAIN OF THE CAUSE OF THE LOSS OF PWR; PLT SWITCHED HIS XPONDER TO 7700 AND CONTACTED APCH AND DECLARED AN EMER AND REQUESTED VECTORS TO THE NEAREST ARPT. THE ATC CTLR INDICATED THAT ZZZ WAS 10 MI STRAIGHT AHEAD. GIVEN THE CURRENT ALT; PLT DETERMINED THAT HE WOULD LIKELY NOT BE ABLE TO GLIDE TO THE ARPT; AND THUS BEGAN LOOKING FOR A FIELD. PLT WAS ASSISTED BY HIS PAX; WHO IS ALSO A PLT; AND TOGETHER THEY LOCATED A COUPLE OF FIELDS AND A DIRT ROAD THAT WERE ALMOST DIRECTLY BELOW THE ACFT. PLT THEN INFORMED ATC THAT THEY WOULD NOT MAKE THE ARPT AND THAT THEY HAD LOCATED AND/OR WERE LOOKING FOR A FIELD. AT SOME POINT; ATC ASKED WHAT THE NATURE OF THE PROB WAS; AND THE PLT INDICATED THAT IT WAS AN ENG/PWR LOSS PROB. PLT THEN GOT HIMSELF PREPARED TO MAKE ONE OF THE FIELDS; AND DETERMINED TO BRING THE THROTTLE BACK AND THEN FULL FORWARD TO DETERMINE HOW MUCH PWR (IF ANY) HE WOULD HAVE AVAILABLE FOR LNDG; IN CASE A GAR WAS NECESSARY. WHEN THE PLT DID THIS; THE ENG CAME BACK TO FULL PWR. THE PLT WAITED AND MANEUVERED SLIGHTLY TO SEE IF THE ENG WOULD REMAIN AT FULL PWR; AND THE ENG SEEMED TO BE PERFORMING NORMALLY. AT THAT POINT; THE PLT CLBED BACK TO 4000 FT MSL(HAD SUFFERED AN ALT LOSS OF BTWN 500-1000 FT) AND THEN INFORMED ATC THAT THE ENG SEEMED TO BE PERFORMING NORMALLY; BUT THAT HE WOULD STILL WANT TO BE VECTORED TO THE CLOSEST ARPT. ATC RESPONDED THAT ZZZ WAS STILL DIRECTLY IN FRONT OF THE ACFT AND ABOUT 8-9 MI AWAY. ATC ASKED IF THE PLT WAS ABLE TO MAINTAIN ALT. THE PLT INDICATED THAT HE COULD MAINTAIN ALT; BUT THAT HE WANTED TO GO AHEAD AND LAND TO DETERMINE THE CAUSE OF THE PROB. PLT THEN FLEW TOWARDS ZZZ AND ATC INFORMED HIM THAT THERE WAS 1 ACFT IN THE PATTERN; WHICH THE PLT SAW AND THEN FOLLOWED TOWARDS THE RWY. PLT THEN INDICATED THAT HE WOULD MAKE THE ARPT AND RPTED THAT THE PLANE SEEMED TO BE ACTING NORMALLY; AND ATC GAVE HIM A NUMBER TO CALL TO CANCEL HIS IFR PLAN. EITHER JUST BEFORE LNDG; OR IMMEDIATELY AFTERWARDS; ANOTHER ACFT CONTACTED THE PLT; ASKED IF EVERYTHING WAS OK; AND THEN ASKED IF THE PLT WANTED HIS IFR PLAN CANCELED. PLT CONFIRMED THAT HE WAS FINE; THAT THE PLAN COULD BE CANCELED; AND TO THANK ATC FOR THEIR HELP. UPON STOPPING THE ENG AND INSPECTING THE ACFT; IT APPEARED THAT THE R TANK WAS COMPLETELY DRY; BUT THAT THE L TANK HAD APPROX 10 GALLONS LEFT. THE PLT THEN TOPPED OFF THE ACFT; STARTED THE ENG; AND THEN RAN IT UP; SWITCHING BTWN BOTH TANKS WITHOUT A PROB. COMFORTABLE THAT THE PROB WAS RESOLVED; THE PLT THEN TOOK OFF VFR AND THEN FLEW TO ZZZ3 AND LANDED WITHOUT INCIDENT. PLT WOULD INDICATE THAT HE BELIEVES THE INITIAL PROB WAS CAUSED BY RUNNING THE R FUEL TANK DRY. FACTORS CONTRIBUTING TO THIS WERE THE STRONG HEADWIND AND THE RATHER CURIOUS ROUTING THAT ATC GAVE THE ACFT FROM ZZZ2 TO ZZZ3. WHILE THE PLT THOUGHT HE HAD PLENTY OF FUEL IN THE R TANK; THE EVIDENCE WOULD INDICATE OTHERWISE. AS FAR AS THE FAILURE OF THE TANK SWITCH TO IMMEDIATELY SOLVE THE PROB; THE PLT IS UNCERTAIN WHY THIS OCCURRED. THE PLT HAS NOT HAD ANY PROBS SWITCHING TANKS BEFORE OR AFTER THIS INCIDENT; SO HE CAN ONLY ASSUME PERHAPS IT WAS SOMETHING (AIR OR DEBRIS IN THE FUEL LINE.

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.