Narrative:

Shortly after takeoff; I was notified by departure that another pilot saw what appeared to be smoke emanating from the right engine as I took off. I responded to departure that everything appeared normal at that time but within seconds after that comment; the right oil pressure dropped followed by a low oil pressure warning light. I then informed departure I was turning right to return and they cleared me direct. I completed and complied with the low oil pressure checklist; requiring me to shut down the engine. Since I shut down the engine; I declared an emergency at that time. I returned; completing all required checklists; and landed the aircraft uneventfully. Upon removal of the engine cowlings and inspection of the engine; it was found that an access plate on the top of the engine was not secured properly and blew open during the takeoff roll; spraying oil on the engine. The maintenance facility that worked on the aircraft; informed me that another vendor did the borescope inspection on the engine and must have failed to properly secure the access plate after their inspection. [That vendor] secured the access plate; re-filled the engine with oil and the engine was ran to confirm that it was operating normally and no longer leaking any oil. East texas turbine cleared the engine to fly; so I flew the aircraft uneventfully on the ferry flight.

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Original NASA ASRS Text

Title: CE550 pilot is informed by ATC shortly after takeoff that smoke appeared to be coming from the right engine. Within seconds low oil quantity and pressure are noted and the right engine is shut down. The flight returns to the departure airport where maintenance error is found to be the cause of the oil leak.

Narrative: Shortly after takeoff; I was notified by Departure that another pilot saw what appeared to be smoke emanating from the right engine as I took off. I responded to Departure that everything appeared normal at that time but within seconds after that comment; the right oil pressure dropped followed by a low oil pressure warning light. I then informed departure I was turning right to return and they cleared me direct. I completed and complied with the low oil pressure checklist; requiring me to shut down the engine. Since I shut down the engine; I declared an emergency at that time. I returned; completing all required checklists; and landed the aircraft uneventfully. Upon removal of the engine cowlings and inspection of the engine; it was found that an access plate on the top of the engine was not secured properly and blew open during the takeoff roll; spraying oil on the engine. The Maintenance facility that worked on the aircraft; informed me that another vendor did the borescope inspection on the engine and must have failed to properly secure the access plate after their inspection. [That vendor] secured the access plate; re-filled the engine with oil and the engine was ran to confirm that it was operating normally and no longer leaking any oil. East Texas Turbine cleared the engine to fly; so I flew the aircraft uneventfully on the ferry flight.

Data retrieved from NASA's ASRS site as of July 2013 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.