Narrative:

Showtime for the flight was XB00. I arrived at the airport at XA50 and immediately proceeded to the aircraft. I stowed my overnight bag and flight bag and proceeded to complete the readying of the aircraft. I followed my routine by removing the starboard tie-down and pitot cover. I rolled the tie-down into a neat bundle and proceeded to the starboard engine cowl to remove the battery charger. I opened the cowl and installed the cowl strut. While removing the charger; I hit the strut with my right elbow; where upon the cowl collapsed on my skull and shoulder. I reopened the cowl and replaced the strut and completed removing the charger and connecting the battery. Secured cowl. I proceeded to the propeller and removed the propeller restraint. I then carried the battery charger to the storage area and did the same with the extension cord carrier and picked up a work towel to see if my scalp was bleeding. I returned to the propeller and collected the tie-down; pitot cover; and propeller restraint and placed them in the aft cargo bin. I did not remove the inlet plugs. I then removed the port pitot cover and tie-down and placed them in the cargo bin. I then proceeded to complete the normal preflight procedure. Engine start was normal with normal engine indications. The bypass handle was extended and remained extended. First flight items were completed at the departure end of runway. Takeoff was normal. All engine indications throughout the flight were normal. The aircraft was flown 3 legs. Upon return; I noted that the bypass handle was difficult to stow. I informed maintenance and the aircraft was grounded upon discovery that the inlet plug had not been removed. Contributing factor to this event was the collapse of the cowling on my shoulder and skull; interrupting the normal sequence of flight preparations; and darkness. Recommendations: remove before flight pennants to the inlet and oil cooler plus so that they are visible below the bottom of the cowling. Fabricate inlet and oil cooler plugs made of bright yellow or white material. Emphasize to all pilots that the interruption or disruption of any flow; checklist; or procedure requires restarting the flow; checklist; or procedure from the beginning.

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Original NASA ASRS Text

Title: C208 PILOT DOES NOT REMOVE INLET PLUGS DURING PREFLIGHT AND FLIES THREE LEGS BEFORE THE OMISSION IS NOTICED. ALL LEGS WERE FLOWN WITH INERTIAL SEPARATOR/BYPASS HANDLE PULLED.

Narrative: SHOWTIME FOR THE FLT WAS XB00. I ARRIVED AT THE ARPT AT XA50 AND IMMEDIATELY PROCEEDED TO THE ACFT. I STOWED MY OVERNIGHT BAG AND FLT BAG AND PROCEEDED TO COMPLETE THE READYING OF THE ACFT. I FOLLOWED MY ROUTINE BY REMOVING THE STARBOARD TIE-DOWN AND PITOT COVER. I ROLLED THE TIE-DOWN INTO A NEAT BUNDLE AND PROCEEDED TO THE STARBOARD ENG COWL TO REMOVE THE BATTERY CHARGER. I OPENED THE COWL AND INSTALLED THE COWL STRUT. WHILE REMOVING THE CHARGER; I HIT THE STRUT WITH MY R ELBOW; WHERE UPON THE COWL COLLAPSED ON MY SKULL AND SHOULDER. I REOPENED THE COWL AND REPLACED THE STRUT AND COMPLETED REMOVING THE CHARGER AND CONNECTING THE BATTERY. SECURED COWL. I PROCEEDED TO THE PROP AND REMOVED THE PROP RESTRAINT. I THEN CARRIED THE BATTERY CHARGER TO THE STORAGE AREA AND DID THE SAME WITH THE EXTENSION CORD CARRIER AND PICKED UP A WORK TOWEL TO SEE IF MY SCALP WAS BLEEDING. I RETURNED TO THE PROP AND COLLECTED THE TIE-DOWN; PITOT COVER; AND PROP RESTRAINT AND PLACED THEM IN THE AFT CARGO BIN. I DID NOT REMOVE THE INLET PLUGS. I THEN REMOVED THE PORT PITOT COVER AND TIE-DOWN AND PLACED THEM IN THE CARGO BIN. I THEN PROCEEDED TO COMPLETE THE NORMAL PREFLT PROC. ENG START WAS NORMAL WITH NORMAL ENG INDICATIONS. THE BYPASS HANDLE WAS EXTENDED AND REMAINED EXTENDED. FIRST FLT ITEMS WERE COMPLETED AT THE DEP END OF RWY. TKOF WAS NORMAL. ALL ENG INDICATIONS THROUGHOUT THE FLT WERE NORMAL. THE ACFT WAS FLOWN 3 LEGS. UPON RETURN; I NOTED THAT THE BYPASS HANDLE WAS DIFFICULT TO STOW. I INFORMED MAINT AND THE ACFT WAS GNDED UPON DISCOVERY THAT THE INLET PLUG HAD NOT BEEN REMOVED. CONTRIBUTING FACTOR TO THIS EVENT WAS THE COLLAPSE OF THE COWLING ON MY SHOULDER AND SKULL; INTERRUPTING THE NORMAL SEQUENCE OF FLT PREPARATIONS; AND DARKNESS. RECOMMENDATIONS: REMOVE BEFORE FLT PENNANTS TO THE INLET AND OIL COOLER PLUS SO THAT THEY ARE VISIBLE BELOW THE BOTTOM OF THE COWLING. FABRICATE INLET AND OIL COOLER PLUGS MADE OF BRIGHT YELLOW OR WHITE MATERIAL. EMPHASIZE TO ALL PLTS THAT THE INTERRUPTION OR DISRUPTION OF ANY FLOW; CHKLIST; OR PROC REQUIRES RESTARTING THE FLOW; CHKLIST; OR PROC FROM THE BEGINNING.

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