Narrative:

During ground roll on takeoff, engine cowling flew open on the right side. The aircraft had been warmed up before flight using a herman nelson on the right side of the aircraft. Before startup, the hose was removed from the right engine cowling by ground personnel and closed. I did a walkaround and found everything to be in order, and after startup with an APU, was given thumbs up by a company employee for taxi. After a normal runup, I was cleared for takeoff. During my takeoff roll, and at about 40-50 KTS of airspeed, I noticed that the right engine cowling started to lift up in the air, so I pulled the power back to idle and stopped on the runway. I came to a full stop with more than 70% of the runway remaining. After clearing the runway, the cowling was examined and found to be in good working condition. I determined that the cowling had not been properly latched after the herman nelson was removed. During my walkaround, I failed to physically test the cowling to make sure it was properly secured.

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Original NASA ASRS Text

Title: AN SMT REJECTED TKOF AT 40-50 KTS DUE TO R ENG COWLING OPENING.

Narrative: DURING GND ROLL ON TKOF, ENG COWLING FLEW OPEN ON THE R SIDE. THE ACFT HAD BEEN WARMED UP BEFORE FLT USING A HERMAN NELSON ON THE R SIDE OF THE ACFT. BEFORE STARTUP, THE HOSE WAS REMOVED FROM THE R ENG COWLING BY GND PERSONNEL AND CLOSED. I DID A WALKAROUND AND FOUND EVERYTHING TO BE IN ORDER, AND AFTER STARTUP WITH AN APU, WAS GIVEN THUMBS UP BY A COMPANY EMPLOYEE FOR TAXI. AFTER A NORMAL RUNUP, I WAS CLRED FOR TKOF. DURING MY TKOF ROLL, AND AT ABOUT 40-50 KTS OF AIRSPD, I NOTICED THAT THE R ENG COWLING STARTED TO LIFT UP IN THE AIR, SO I PULLED THE PWR BACK TO IDLE AND STOPPED ON THE RWY. I CAME TO A FULL STOP WITH MORE THAN 70% OF THE RWY REMAINING. AFTER CLRING THE RWY, THE COWLING WAS EXAMINED AND FOUND TO BE IN GOOD WORKING CONDITION. I DETERMINED THAT THE COWLING HAD NOT BEEN PROPERLY LATCHED AFTER THE HERMAN NELSON WAS REMOVED. DURING MY WALKAROUND, I FAILED TO PHYSICALLY TEST THE COWLING TO MAKE SURE IT WAS PROPERLY SECURED.

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.