MU-300 Diamond 1/1A
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Flight Crew Last 90 Days 100; Flight Crew Total 16000; Flight Crew Type 2200
Confusion; Workload; Distraction; Communication Breakdown
Aircraft Equipment Problem Critical; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance
Flight Crew FLC complied w / Automation / Advisory; Flight Crew Returned To Departure Airport; Flight Crew Landed in Emergency Condition; Flight Crew Inflight Shutdown; General Maintenance Action; General Declared Emergency
Aircraft; Human Factors
Normal takeoff and vectored south to the departure. Passing about 5;000 FT the left engine low oil pressure warning light illuminated. The left engine was brought back to idle. The oil press continued to drop and the engine was shut down within 10 seconds of the light coming on.  ATC was notified that we needed [an] immediate return to airport. They responded with vectors back toward the active Runway 12R ILS. We were descended to 3;000 FT. ATC asked if we needed assistance and we responded not at this time; we had shut an engine down and needed to return for landing. I felt at the time that everything was under control and did not need to declare an emergency.  We were given a turn to 360. We responded with 'turn 360.' However the pilot not flying had set in a heading of 130 and we were paralleling the final. I was following the command bars and getting the plane set up for the final. I did not notice the error until ATC asked why was heading in that direction. I immediately turned to 360. By this time we were high and close to the FAF. ATC indicated that they were going to have to take us back around to intercept the inbound. At this point we declared an emergency and ATC gave us one more vector to final and cleared us for approach. The approach and landing were uneventful. In retrospect I should have immediately declared an emergency when we shut down the engine. It would have been helpful to ATC.
I thought I heard a turn to 080; and we turned; only to find out that it was supposed to be 030. This apparently brought us too close to the final course; as the Controller told up he would have to vector us back around for another approach. At that point I declared an emergency to receive priority handling; so that we could get on the ground. He continued to vector us to shoot the ILS 12R approach; and we made a landing without incident. Although we did not require assistance; the fire trucks rolled to greet us and followed us to our hangar as a precautionary measure. In retrospect; I could have declared the emergency sooner; in order to avoid any confusion on the part of ATC and to ensure priority handling. Other than that; the checklists were performed; and the Captain and I handled the situation just as we should have.
An MU-300 left engine oil pressure decreased then indicated zero so the engine was shut down; the checklist completed and after a missed vector for an immediate landing; an uneventful landing followed.