Narrative:

We performed a run-up and determined that the airplane was safe for its first flight of the day. We ran all appropriate checklists and took off without incident. Climbing through 22;000 ft the master warning flasher illuminated with no associated annunciator. Approximately 10 seconds later; the right oil pressure low annunciator illuminated along with oil pressure and torque gauge fluctuations. The engine performance was rapidly decreasing and we elected to shut the engine down in flight; as the checklist required us to do. We secured the right engine; made a right turn back to [departure] airport; declared an emergency and began a slow descent. In the descent; we got updated weather; ran all appropriate checklists; and coordinated crash; fire; rescue operations with air traffic control. We were cleared for the visual approach and landed without further incident. After the airplane was brought to a complete stop; we shut down the running (left) engine and were towed off the runway back to the maintenance hangar.

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Original NASA ASRS Text

Title: B1900 flight crew reported low oil pressure in right engine climbing through FL220. Engine was shut down; an emergency declared; and a return to departure airport was safely executed.

Narrative: We performed a run-up and determined that the airplane was safe for its first flight of the day. We ran all appropriate checklists and took off without incident. Climbing through 22;000 FT the Master Warning flasher illuminated with no associated annunciator. Approximately 10 seconds later; the Right Oil Pressure Low annunciator illuminated along with oil pressure and torque gauge fluctuations. The engine performance was rapidly decreasing and we elected to shut the engine down in flight; as the checklist required us to do. We secured the right engine; made a right turn back to [departure] airport; declared an emergency and began a slow descent. In the descent; we got updated weather; ran all appropriate checklists; and coordinated Crash; Fire; Rescue Operations with Air Traffic Control. We were cleared for the visual approach and landed without further incident. After the airplane was brought to a complete stop; we shut down the running (left) engine and were towed off the runway back to the maintenance hangar.

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.