Narrative:

Upon climb-out I noticed the left engine oil pressure falling from 50 psi indicated on takeoff to 35 psi. Being suspect of the left engine from a previous flight; I notified ATC that I would be returning to land due to a low oil pressure indication on the left engine. ATC gave me a vector to the final for ILS and descended me from 6;000 ft to 2;300 ft for an intercept. Just outside the FAF for ILS the left engine oil pressure was showing around 5 psi and the left tachometer was beginning to decrease in RPM along with an audible change in propeller noise. I decided to shutdown and feather the left engine in a controlled manner before it lost all oil pressure. The ILS was then flown single engine to about 1;000 ft AGL where I broke out of the cloud bases and saw the runway. I notified the tower that the left engine was shut down and declined any emergency services to be waiting upon landing.

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Original NASA ASRS Text

Title: Beechcraft Baron pilot shut down the left engine due to low oil pressure indication and returned to departure airport.

Narrative: Upon climb-out I noticed the left engine oil pressure falling from 50 PSI indicated on takeoff to 35 PSI. Being suspect of the left engine from a previous flight; I notified ATC that I would be returning to land due to a low oil pressure indication on the left engine. ATC gave me a vector to the Final for ILS and descended me from 6;000 FT to 2;300 FT for an intercept. Just outside the FAF for ILS the left engine oil pressure was showing around 5 PSI and the Left tachometer was beginning to decrease in RPM along with an audible change in propeller noise. I decided to shutdown and feather the left engine in a controlled manner before it lost all oil pressure. The ILS was then flown single engine to about 1;000 FT AGL where I broke out of the cloud bases and saw the runway. I notified the Tower that the left engine was shut down and declined any emergency services to be waiting upon landing.

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.