Narrative:

On the takeoff at 1000' AGL, 2000' MSL, climb power was set and flaps 12 degree called for. At this time I felt what appeared to be a bird strike. The first officer felt it and the F/east also. It felt like a strike on the lower section of the nose cone of aircraft. I had the F/east check all engine indications and fluid levels, etc. There were no adverse yaw conditions, no vibrations or abnormal flight characteristics. After discussing it with the first officer and F/east, I decided to continue the flight from day to mia, a 2 hour flight. Throughout the flight all appeared normal. After landing in miami which was a normal landing with no indications of abnormals, we noticed the #3 engine cowling had separated from the aircraft and an 8' hole was ripped on the top leading edge of the right wing. I believe the cowling lacks either broke or were not fastened or partially fastened. The second officer and myself both did our preflight walkaround and noticed maintenance working on #2 and #4 engines with the cowlings open. The temperature outside was -3 with a 15 KT wind, which is about a -27 degree wind chill and the ramp had a 2' cover of ice and snow which is very hard to work on. If the #3 cowl was opened this day it is possible that human performance in these conditions was very much deteriorated. After maintenance gave us the green condition to fly I had the second officer go outside again and check the aircraft over, as he had several times previously. So I believe the cowling was fastened and a possible bird strike, it was partially fastened, not fastened at all, or the locks broke. However due to working conditions, I believe it was fastened hastily and was only partially fastened. That's why it held together during the takeoff roll and up to 1000' AGL and 210 KTS airspeed. I also believe when temperatures reach a certain degree, all maintenance should be performed inside and a hangar provided and mandatory. Also on a cargo aircraft we can't get to the back and look through the windows like a passenger aircraft. So if a method of mirrors or windows could be made, a lot of problems on the engines and airframe aft of the cockpit could be handled better.

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Original NASA ASRS Text

Title: ACR HVT LOST THE 3# ENGINE COWL ON CLIMBOUT. PROBLEM NOT DISCOVERED UNTIL THE END OF A 2 HOUR FLT AT DESTINATION.

Narrative: ON THE TKOF AT 1000' AGL, 2000' MSL, CLB PWR WAS SET AND FLAPS 12 DEG CALLED FOR. AT THIS TIME I FELT WHAT APPEARED TO BE A BIRD STRIKE. THE F/O FELT IT AND THE F/E ALSO. IT FELT LIKE A STRIKE ON THE LOWER SECTION OF THE NOSE CONE OF ACFT. I HAD THE F/E CHK ALL ENG INDICATIONS AND FLUID LEVELS, ETC. THERE WERE NO ADVERSE YAW CONDITIONS, NO VIBRATIONS OR ABNORMAL FLT CHARACTERISTICS. AFTER DISCUSSING IT WITH THE F/O AND F/E, I DECIDED TO CONTINUE THE FLT FROM DAY TO MIA, A 2 HR FLT. THROUGHOUT THE FLT ALL APPEARED NORMAL. AFTER LNDG IN MIAMI WHICH WAS A NORMAL LNDG WITH NO INDICATIONS OF ABNORMALS, WE NOTICED THE #3 ENG COWLING HAD SEPARATED FROM THE ACFT AND AN 8' HOLE WAS RIPPED ON THE TOP LEADING EDGE OF THE RIGHT WING. I BELIEVE THE COWLING LACKS EITHER BROKE OR WERE NOT FASTENED OR PARTIALLY FASTENED. THE S/O AND MYSELF BOTH DID OUR PREFLT WALKAROUND AND NOTICED MAINT WORKING ON #2 AND #4 ENGS WITH THE COWLINGS OPEN. THE TEMP OUTSIDE WAS -3 WITH A 15 KT WIND, WHICH IS ABOUT A -27 DEG WIND CHILL AND THE RAMP HAD A 2' COVER OF ICE AND SNOW WHICH IS VERY HARD TO WORK ON. IF THE #3 COWL WAS OPENED THIS DAY IT IS POSSIBLE THAT HUMAN PERFORMANCE IN THESE CONDITIONS WAS VERY MUCH DETERIORATED. AFTER MAINT GAVE US THE GREEN CONDITION TO FLY I HAD THE S/O GO OUTSIDE AGAIN AND CHK THE ACFT OVER, AS HE HAD SEVERAL TIMES PREVIOUSLY. SO I BELIEVE THE COWLING WAS FASTENED AND A POSSIBLE BIRD STRIKE, IT WAS PARTIALLY FASTENED, NOT FASTENED AT ALL, OR THE LOCKS BROKE. HOWEVER DUE TO WORKING CONDITIONS, I BELIEVE IT WAS FASTENED HASTILY AND WAS ONLY PARTIALLY FASTENED. THAT'S WHY IT HELD TOGETHER DURING THE TKOF ROLL AND UP TO 1000' AGL AND 210 KTS AIRSPD. I ALSO BELIEVE WHEN TEMPS REACH A CERTAIN DEG, ALL MAINT SHOULD BE PERFORMED INSIDE AND A HANGAR PROVIDED AND MANDATORY. ALSO ON A CARGO ACFT WE CAN'T GET TO THE BACK AND LOOK THROUGH THE WINDOWS LIKE A PAX ACFT. SO IF A METHOD OF MIRRORS OR WINDOWS COULD BE MADE, A LOT OF PROBS ON THE ENGS AND AIRFRAME AFT OF THE COCKPIT COULD BE HANDLED BETTER.

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