Narrative:

After takeoff, ground personnel notified us that after our departure a large piece of an aircraft had been found on the runway. We felt no abnormal airframe vibration. Also heard nothing abnormal so the flight was continued. Short time later, ground crew notified us that piece was lower engine cowl and that numbering placed it off our aircraft. We immediately returned for an uneventful landing.

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Original NASA ASRS Text

Title: CPR ACFT ON A DEMO TEST FLT LOSES PART OF ENG COWLING DURING TKOF. FLC IS NOTIFIED OF THIS BY COMPANY AND RETURNS TO ARPT.

Narrative: AFTER TKOF, GND PERSONNEL NOTIFIED US THAT AFTER OUR DEP A LARGE PIECE OF AN ACFT HAD BEEN FOUND ON THE RWY. WE FELT NO ABNORMAL AIRFRAME VIBRATION. ALSO HEARD NOTHING ABNORMAL SO THE FLT WAS CONTINUED. SHORT TIME LATER, GND CREW NOTIFIED US THAT PIECE WAS LOWER ENG COWL AND THAT NUMBERING PLACED IT OFF OUR ACFT. WE IMMEDIATELY RETURNED FOR AN UNEVENTFUL LNDG.

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.