Narrative:

On missed approach runway 3, right side engine oil pressure low, red annunciator light illuminated. We told tower that we had a problem and asked for immediate return to land. Tower advised us to contact departure controller. We called departure and again requested immediate return to land. Controller replied that we would be #7 in sequence. We felt that situation with the right engine could get worse and we should land as soon as possible. To be able to land immediately we had to declare an emergency. Callback conversation with reporter revealed the following information: the reporter stated the engine oil pressure indicator was reading normal pressure but the red annunciator low pressure warning light was illuminated. The reporter said company procedure is to return to land when this annunciator warning is illuminated. The reporter stated maintenance advised the crew the oil pressure switch was defective and the warning was false.

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Original NASA ASRS Text

Title: A BEECH 400A, ON INITIAL CLB 1500 FT TO 3000 FT, DECLARED AN EMER AND DIVERTED DUE TO #2 ENG LOW OIL PRESSURE RED ANNUNCIATOR WARNING CAUSED BY A FAILED LOW PRESSURE WARNING SWITCH.

Narrative: ON MISSED APCH RWY 3, R SIDE ENG OIL PRESSURE LOW, RED ANNUNCIATOR LIGHT ILLUMINATED. WE TOLD TWR THAT WE HAD A PROB AND ASKED FOR IMMEDIATE RETURN TO LAND. TWR ADVISED US TO CONTACT DEP CTLR. WE CALLED DEP AND AGAIN REQUESTED IMMEDIATE RETURN TO LAND. CTLR REPLIED THAT WE WOULD BE #7 IN SEQUENCE. WE FELT THAT SIT WITH THE R ENG COULD GET WORSE AND WE SHOULD LAND ASAP. TO BE ABLE TO LAND IMMEDIATELY WE HAD TO DECLARE AN EMER. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE ENG OIL PRESSURE INDICATOR WAS READING NORMAL PRESSURE BUT THE RED ANNUNCIATOR LOW PRESSURE WARNING LIGHT WAS ILLUMINATED. THE RPTR SAID COMPANY PROC IS TO RETURN TO LAND WHEN THIS ANNUNCIATOR WARNING IS ILLUMINATED. THE RPTR STATED MAINT ADVISED THE CREW THE OIL PRESSURE SWITCH WAS DEFECTIVE AND THE WARNING WAS FALSE.

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