Narrative:

I arrived at the airport early in anticipation of favorable weather to perform several practice IFR approaches at a nearby airport. Unfortunately a layer of fog and haze had set in that reduced visibility at the departure airport below minimums making an IFR departure an unfavorable option in case I had to return with an emergency. I spent the morning doing cleanup work around the aircraft and performing parts of the preflight checklist including removing the cover; checking oil and tire pressure. The checklist procedures were not performed in the standard order and executed as part of other tasks. The weather finally broke and the cloud layer had risen high enough to provide for a safe IFR departure. I started the engine and taxied to the runway for run-up. The temperatures were relatively cool in the mid 50's and the engine run-up was normal. After receiving IFR clearance I departed the airport without incident. As part of the climb out I noticed RPM levels were lower then expected and my climb would not safely increase over 500 fpm without speed dropping. In thinking through possible scenarios I realized that in the process of performing my non-standard checklist I may have forgotten to remove the cowling plugs. Although my climb rate was less then optimal I was able to maintain altitude sufficient to continue flight without overburdening the engine pressure and temperature. My options were to immediately return to the departure airport and into IFR conditions or continue in visual conditions above the cloud layer to an airport I new had visual flight conditions. The option to continue flight would only add 5 minutes to total time and would position me in an area with visual conditions if an emergency landing was required. I requested from the controller that I maintain current altitude and continue direct to destination with an anticipated visual approach. I arrived at the airport without adverse engine problems and immediately pulled the plugs and checked engine status. The plugs and streamer were still intact and the oil level and smell appeared normal. The obvious lesson was to strictly observe the preflight checklist and do not deviate or perform concurrent tasks. Prior to flight perform one final walk around.

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Original NASA ASRS Text

Title: PA28 pilot reports reduced engine power during climb and suspects that he forgot to remove the cowling plugs during preflight. No engine parameters are exceeded and the reporter is able to land safely and remove the plugs.

Narrative: I arrived at the airport early in anticipation of favorable weather to perform several practice IFR approaches at a nearby airport. Unfortunately a layer of fog and haze had set in that reduced visibility at the departure airport below minimums making an IFR departure an unfavorable option in case I had to return with an emergency. I spent the morning doing cleanup work around the aircraft and performing parts of the preflight checklist including removing the cover; checking oil and tire pressure. The checklist procedures were not performed in the standard order and executed as part of other tasks. The weather finally broke and the cloud layer had risen high enough to provide for a safe IFR departure. I started the engine and taxied to the runway for run-up. The temperatures were relatively cool in the mid 50's and the engine run-up was normal. After receiving IFR clearance I departed the airport without incident. As part of the climb out I noticed RPM levels were lower then expected and my climb would not safely increase over 500 fpm without speed dropping. In thinking through possible scenarios I realized that in the process of performing my non-standard checklist I may have forgotten to remove the cowling plugs. Although my climb rate was less then optimal I was able to maintain altitude sufficient to continue flight without overburdening the engine pressure and temperature. My options were to immediately return to the departure airport and into IFR conditions or continue in visual conditions above the cloud layer to an airport I new had visual flight conditions. The option to continue flight would only add 5 minutes to total time and would position me in an area with visual conditions if an emergency landing was required. I requested from the Controller that I maintain current altitude and continue direct to destination with an anticipated visual approach. I arrived at the airport without adverse engine problems and immediately pulled the plugs and checked engine status. The plugs and streamer were still intact and the oil level and smell appeared normal. The obvious lesson was to strictly observe the preflight checklist and do not deviate or perform concurrent tasks. Prior to flight perform one final walk around.

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.