Narrative:

The aircraft had undergone a regularly scheduled oil change the day before the flight as well as an adjustment of the propeller governor. Preflight inspection was carried out and was normal. Take off and climb to altitude were without incident. Once established in cruise; approximately 40 minutes after take off with the engine settings in the correct configuration for cruise - manifold pressure of 31.5'hg; RPM 2300; power 72%; fuel flow 15.9 gph; normal oil temperature and pressure and the engine cylinder head temperatures all below 360 - the autopilot was engaged. At this point; during a scan I noted that the speed was decaying. I checked tailwind and altitude which had not changed and then switched my scan to the engine page. The manifold pressure and RPM were decaying rapidly to 20.8'hg and 1800RPM. There was only a small drop in oil pressure to about 55 psi. I rapidly ran the check list and established that fuel flow was not an issue and that the engine was not responding in an appropriate manner so duly declared an emergency and asked for the nearest airport. While waiting for ATC to respond I disengaged the autopilot; adopted a nose-down attitude (airspeed had dropped from about 150 KIAS to 130 by this point) and retarded the throttle to limit the chance for further engine issues. ATC provided several options for a landing and I selected ZZZ as this provided a long runway for a power-off landing; emergency services and given the winds aloft would provide the best options. We discussed runway options and I chose runway 36R and set up the ILS so I could evaluate my glide slope. ATC asked about fuel aboard and I provided this data - approximately 360 pounds. The landing was without incident and I was able to roll the aircraft to the FBO with no power application. Emergency equipment followed me and after I shut down the aircraft I provided them with the required information. On exiting the aircraft a trail of oil was visible on the tarmac and under the starboard side of the plane. Later inspection revealed that the rocker arm of the exhaust valve on cylinder #1 had become loose and had punched a hole in the rocker arm cover; causing a loss of oil which had doubtlessly caused a loss of turbo-boosting.

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Original NASA ASRS Text

Title: A Lancair Columbia pilot declared an emergency and diverted to a nearby airport when he suffered a loss of power at FL190.

Narrative: The aircraft had undergone a regularly scheduled oil change the day before the flight as well as an adjustment of the propeller governor. Preflight inspection was carried out and was normal. Take off and climb to altitude were without incident. Once established in cruise; approximately 40 minutes after take off with the engine settings in the correct configuration for cruise - manifold pressure of 31.5'Hg; RPM 2300; power 72%; fuel flow 15.9 GPH; normal oil temperature and pressure and the engine cylinder head temperatures all below 360 - the autopilot was engaged. At this point; during a scan I noted that the speed was decaying. I checked tailwind and altitude which had not changed and then switched my scan to the engine page. The manifold pressure and RPM were decaying rapidly to 20.8'Hg and 1800RPM. There was only a small drop in oil pressure to about 55 PSI. I rapidly ran the check list and established that fuel flow was not an issue and that the engine was not responding in an appropriate manner so duly declared an emergency and asked for the nearest airport. While waiting for ATC to respond I disengaged the autopilot; adopted a nose-down attitude (airspeed had dropped from about 150 KIAS to 130 by this point) and retarded the throttle to limit the chance for further engine issues. ATC provided several options for a landing and I selected ZZZ as this provided a long runway for a power-off landing; emergency services and given the winds aloft would provide the best options. We discussed runway options and I chose Runway 36R and set up the ILS so I could evaluate my glide slope. ATC asked about fuel aboard and I provided this data - approximately 360 pounds. The landing was without incident and I was able to roll the aircraft to the FBO with no power application. Emergency equipment followed me and after I shut down the aircraft I provided them with the required information. On exiting the aircraft a trail of oil was visible on the tarmac and under the starboard side of the plane. Later inspection revealed that the rocker arm of the exhaust valve on cylinder #1 had become loose and had punched a hole in the rocker arm cover; causing a loss of oil which had doubtlessly caused a loss of turbo-boosting.

Data retrieved from NASA's ASRS site as of April 2012 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.