Narrative:

The takeoff proceeded normally. At acceleration height; we received a triple-chime and 'engine oil' aural warning and a red EICAS 'rh oil press' warning. I noticed out of the corner of my eye that the right engine oil pressure had momentarily dropped significantly and rather rapidly; however the pressure soon rose back up into a normal value. I thought perhaps it was merely a transient fault in the system until about 5-10 second later it occurred again which indicated to me that the oil pressure in that engine was indeed low. I immediately declared an emergency with departure and requested vectors to our takeoff alternate; as the current weather conditions at our departure airport made a return there a non-consideration except in the most dire of circumstances. I informed the first officer that he had the aircraft and the radios while I performed the QRH procedure. By that time we had started a climb to 5000 feet and a turn toward our alternate. I continued to the QRH and also began observing exactly what the oil pressure was doing. The oil pressure on the affected engine was hovering at about 38 psi and generally did not really increase or decrease from that value regardless of any thrust changes. Other than when the oil pressure dipped below normal (green) values; oil temperatures remained fairly constant. It was at that point that I elected to abandon the QRH procedure and leave the engine running rather than operate the aircraft single engine. I had assumed that we probably weren't losing oil in large amounts but rather there was simply not a large quantity of oil running through the system and it was intermittently circulating like when you try to suck the remainder of a milkshake at the bottom of a cup through a straw. We then set up for a visual approach to runway 22L at ZZZ. Weather conditions there were VFR. Once tasks in the cockpit and with ATC were accomplished; I called the flight attendant over the interphone. I informed him that we declared an emergency; of the situation with the engine and that we would be landing at ZZZ; evacuation is unlikely at this point and that he had 5 minutes to prepare as we were 7 minutes from touchdown. I then called dispatch and informed them of the situation; what we were doing and that we would call them on the ground. Dispatch concurred. I set up the landing data and ran a descent and approach checklist. I informed the first officer that we would be making an overweight landing on the 49;000 pound speed card. I also informed him of the runway length (over 10;000) and that he should touchdown as softly with as small of a rate of descent as possible and that we would roll to the end of the runway due to brake energy considerations. Immediately after landing we contacted operations and I had a fire truck follow us to the gate and at 2 minutes I shut the right engine down. I called dispatch and informed them that we were safely on the ground. I then called maintenance control and discussed the problem with them after which they dispatched contract maintenance. Maintenance then showed up a short time later and after inspection of the right engine; it was determined that there were only 1.7 quarts of oil in the engine. They later determined that there was an oil leak in the system.

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Original NASA ASRS Text

Title: A CRJ-200 diverted to their takeoff alternate following a right engine RH OIL PRESS EICAS warning shortly after taking off.

Narrative: The takeoff proceeded normally. At acceleration height; we received a triple-chime and 'Engine Oil' aural warning and a red EICAS 'RH OIL PRESS' warning. I noticed out of the corner of my eye that the right engine oil pressure had momentarily dropped significantly and rather rapidly; however the pressure soon rose back up into a normal value. I thought perhaps it was merely a transient fault in the system until about 5-10 second later it occurred again which indicated to me that the oil pressure in that engine was indeed low. I immediately declared an emergency with Departure and requested vectors to our takeoff alternate; as the current weather conditions at our departure airport made a return there a non-consideration except in the most dire of circumstances. I informed the First Officer that he had the aircraft and the radios while I performed the QRH procedure. By that time we had started a climb to 5000 feet and a turn toward our alternate. I continued to the QRH and also began observing exactly what the oil pressure was doing. The oil pressure on the affected engine was hovering at about 38 psi and generally did not really increase or decrease from that value regardless of any thrust changes. Other than when the oil pressure dipped below normal (green) values; oil temperatures remained fairly constant. It was at that point that I elected to abandon the QRH procedure and leave the engine running rather than operate the aircraft single engine. I had assumed that we probably weren't losing oil in large amounts but rather there was simply not a large quantity of oil running through the system and it was intermittently circulating like when you try to suck the remainder of a milkshake at the bottom of a cup through a straw. We then set up for a visual approach to Runway 22L at ZZZ. Weather conditions there were VFR. Once tasks in the cockpit and with ATC were accomplished; I called the Flight Attendant over the interphone. I informed him that we declared an emergency; of the situation with the engine and that we would be landing at ZZZ; evacuation is unlikely at this point and that he had 5 minutes to prepare as we were 7 minutes from touchdown. I then called Dispatch and informed them of the situation; what we were doing and that we would call them on the ground. Dispatch concurred. I set up the landing data and ran a Descent and Approach Checklist. I informed the First Officer that we would be making an overweight landing on the 49;000 LB Speed card. I also Informed him of the runway length (over 10;000) and that he should touchdown as softly with as small of a rate of descent as possible and that we would roll to the end of the runway due to brake energy considerations. Immediately after landing we contacted operations and I had a fire truck follow us to the gate and at 2 minutes I shut the right engine down. I called Dispatch and informed them that we were safely on the ground. I then called Maintenance Control and discussed the problem with them after which they dispatched contract maintenance. Maintenance then showed up a short time later and after inspection of the right engine; it was determined that there were only 1.7 quarts of oil in the engine. They later determined that there was an oil leak in the system.

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.