Narrative:

Normal takeoff from runway 18R at ZZZ. At approximately 10000 ft MSL ZZZ departure advised that a 2x2 piece of metal was observed to have fallen off the aircraft during the takeoff roll. Without any further information as what the piece of metal was and knowing that the aircraft had just undergone extensive maintenance I elected immediately to return to ZZZ. The WX was excellent and we were well under maximum landing weight. A normal approach to landing was made on runway 18R at ZZZ. The after takeoff; descent; approach; and final checks were completed. A normal landing and taxi to the gate was performed. One attempt was made to contact dispatch by radio in the air when we were notified by ATC; however; time and workload did not allow multiple attempts. ZZZ tower told us after we exited the runway that it appeared we'd lost our r-hand engine cowling. Recommendation: screw the cowlings on correctly. Have someone double-check things like that.

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Original NASA ASRS Text

Title: A CRJ200'S ENG COWLING FELL OF DURING TKOF. ATC NOTIFIED THE CREW WHO RETURNED THE ACFT TO THE DEPARTURE ARPT.

Narrative: NORMAL TKOF FROM RWY 18R AT ZZZ. AT APPROX 10000 FT MSL ZZZ DEP ADVISED THAT A 2X2 PIECE OF METAL WAS OBSERVED TO HAVE FALLEN OFF THE ACFT DURING THE TKOF ROLL. WITHOUT ANY FURTHER INFO AS WHAT THE PIECE OF METAL WAS AND KNOWING THAT THE ACFT HAD JUST UNDERGONE EXTENSIVE MAINT I ELECTED IMMEDIATELY TO RETURN TO ZZZ. THE WX WAS EXCELLENT AND WE WERE WELL UNDER MAX LNDG WT. A NORMAL APCH TO LNDG WAS MADE ON RWY 18R AT ZZZ. THE AFTER TKOF; DSCNT; APCH; AND FINAL CHKS WERE COMPLETED. A NORMAL LNDG AND TAXI TO THE GATE WAS PERFORMED. ONE ATTEMPT WAS MADE TO CONTACT DISPATCH BY RADIO IN THE AIR WHEN WE WERE NOTIFIED BY ATC; HOWEVER; TIME AND WORKLOAD DID NOT ALLOW MULTIPLE ATTEMPTS. ZZZ TWR TOLD US AFTER WE EXITED THE RWY THAT IT APPEARED WE'D LOST OUR R-HAND ENG COWLING. RECOMMENDATION: SCREW THE COWLINGS ON CORRECTLY. HAVE SOMEONE DOUBLE-CHK THINGS LIKE THAT.

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.