Narrative:

This was a training flight for my part 135 operator. I was the flight instructor (sitting right seat); and the pilot in the left seat was type rated in the aircraft; he also has a current 8410 in the specific aircraft as well (with a different operator). Acting as a crew; we started the aircraft with gpu power. After start checks were conducted and I then obtained ATIS and called clearance; indicating we would be departing VFR to the northwest for training. We began taxi; performed all before takeoff checks; and prepared for takeoff. Taking off as a crew; line up checks were conducted; and the trainee in the left seat was the pilot flying. All cockpit indications were normal during takeoff; and there were no abnormal sounds or vibrations during this phase. We initially flew runway heading (270). At approximately 600 feet; we turned to the assigned heading of 300 and continued climb out to 2000 feet; as assigned by ATC. At approximately 1800 feet; we leveled off to avoid some clouds; and I reported that to the tower. A few seconds after leveling off at 1800 feet; we felt and heard a significant 'thud'. My initial thought was perhaps a piece of ballast had shifted in the rear of the aircraft. We were both assessing the situation; checking instruments; which is when the left seat pilot saw the right upper engine cowl missing. I looked; saw the issue; and assessed the damage. The lower cowl was intact; not vibrating; and I noticed the wing leading edge with a tear in the de-ice boot and a dent as well. We reported to approach that we were missing the upper cowl and needed to return to ZZZ for a precautionary landing. Returning to the field; all flight characteristics were normal. We checked flap and gear normal operation a bit early to preclude any unexpected scenario. The pilot in the left seat made the landing; which was uneventful.

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Original NASA ASRS Text

Title: A SA227's right engine upper cowling departed the engine in flight. An normal precautionary landing was made at the departure airport.

Narrative: This was a training flight for my part 135 operator. I was the Flight Instructor (sitting right seat); and the Pilot in the left seat was type rated in the aircraft; he also has a current 8410 in the specific aircraft as well (with a different operator). Acting as a crew; we started the aircraft with GPU power. After start checks were conducted and I then obtained ATIS and called clearance; indicating we would be departing VFR to the northwest for training. We began taxi; performed all before takeoff checks; and prepared for takeoff. Taking off as a crew; line up checks were conducted; and the trainee in the left seat was the pilot flying. All cockpit indications were normal during takeoff; and there were no abnormal sounds or vibrations during this phase. We initially flew runway heading (270). At approximately 600 feet; we turned to the assigned heading of 300 and continued climb out to 2000 feet; as assigned by ATC. At approximately 1800 feet; we leveled off to avoid some clouds; and I reported that to the Tower. A few seconds after leveling off at 1800 feet; we felt and heard a significant 'thud'. My initial thought was perhaps a piece of ballast had shifted in the rear of the aircraft. We were both assessing the situation; checking instruments; which is when the left seat Pilot saw the right upper engine cowl missing. I looked; saw the issue; and assessed the damage. The lower cowl was intact; not vibrating; and I noticed the wing leading edge with a tear in the De-ice boot and a dent as well. We reported to Approach that we were missing the upper cowl and needed to return to ZZZ for a precautionary landing. Returning to the field; all flight characteristics were normal. we checked flap and gear normal operation a bit early to preclude any unexpected scenario. The Pilot in the left seat made the landing; which was uneventful.

Data retrieved from NASA's ASRS site as of April 2012 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.