Date: 201209
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Flight conditions: IMC
Weather elements / visibility: Fog; Rain; 4
Light: Daylight
Aircraft: King Air C90 E90
Operator: Corporate
Operating under: Part 91
Flight plan: IFR
Mission: Passenger
Flight phase: Descent
Airspace: Class C ZZZ
ATC / advisory: TRACON ZZZ
Aircraft component: Turbine Engine
Component problem: Malfunctioning
Reporter organization: Corporate
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Commercial; Flight Crew Flight Instructor
Human factors: Other / Unknown
Anomaly: Aircraft Equipment Problem Critical
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Overcame Equipment Problem; General Maintenance Action; General Declared Emergency
Contributing factors: Human Factors; Aircraft; Weather
Primary problem: Ambiguous

Narrative: Flight day originated from our company base with the plane unhangared and sitting in rain all night. We started our preflight in the dark and rain. I conducted the exterior portion of the preflight and neglected to sump the aircraft fuel system. This may have been a critical check that might have found the most likely cause. Whether I could or would have found water in the fuel system with a flashlight in the pouring rain is uncertain; but looking back I certainly regret not doing so as we would have a significant data point in the chain of events. We proceed on an IFR flight in constant IMC and rain to pick up one passenger (first leg) and proceeded to our destination (second leg). We had onboard weather radar and NEXRAD data and had already determined that proceeding around the worst of the rain and weather to the north; was our most prudent route. We had four hours of fuel on board for what was a 1+15 flight to our destination. Aside from the heavy rain we proceeded normally on our flight plan to a cruising altitude of 14;000 FT MSL. We got the weather at our destination which was around 2;000 FT broken and 4 SM with valley fog reporting on ATIS. We planned the RNAV 23 which was the active runway at the time and allowed us better minimums since the ILS 23 glide path was out of service. Approximately 5 miles prior to the IAF I noticed our Number 2 Engine gauges rolling back. I announced this to my First Officer and he concurred. I conducted the memory items for engine failure and directed the First Officer to run the Engine Failure Checklist in our Quick Reference Handbook (QRH). We also declared an emergency with Approach and requested holding at 4;000 FT MSL while we attempted to restart the failed engine. Thankfully the engine restarted on the first attempt; using our Restart Checklist found in the QRH. At this time we were nearing the IAF again and requested clearance for the approach to a full stop at our destination. We were cleared approach and flew the RNAV 23 to near minimums and had an uneventful 2 engine landing; taxied clear; closed the emergency with Tower; and taxied to the FBO shutting down normally. Later that day; a pilot and mechanic from our company flew into our destination and investigated the aircraft to try to determine the cause. Upon inspection of the engines and fuel strainers; they found a significant amount of water throughout the fuel system; particularly in the engine nacelle tanks and fuel filters. We believe the cause of the flame-out was water ingestion. It seems most likely that water seeped in through fuel caps on the ground; but since the plane flew through significant precipitation and was in rain during the flame-out; it is hard to know for certain. Certainly the fuel caps need to be thoroughly inspected; as well as the fuel tanks and venting system. We do not have all that data at this time. The importance of fuel sumping on preflight is the biggest lesson I take away from this incident.




Synopsis: BE9L Captain reports departing on a two leg flight in an aircraft that had spent the night out in the rain; with both legs of the flight also in rain. During approach on the second leg the right engine shuts down. QRH procedures are complied with and the engine is successfully restarted and a normal two engine landing ensues. Maintenance discovers a substantial amount of water in the fuel system.