Date: 201706
Local time of day: 1201-1800
Location: ZZZ.Airport, US
Flight conditions: VMC
Light: Daylight
Aircraft: Citation Excel (C560XL)
Operator: Air Taxi
Operating under: Part 91
Flight plan: IFR
Mission: Ferry / Re-Positioning
Flight phase: Climb
Airspace: Class E ZZZ
ATC / advisory: TRACON ZZZ
Aircraft component: Wing Fueling Panel
Component problem: Improperly Operated
Reporter organization: Air Taxi
Reporter function: Captain
Reporter qualification: Flight Crew Multiengine; Flight Crew Flight Instructor; Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument
Human factors: Situational Awareness
Anomaly: Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: In-flight
Result: Aircraft Aircraft Damaged; Flight Crew Diverted; Flight Crew Landed in Emergency Condition; Flight Crew Returned To Departure Airport
Contributing factors: Aircraft; Human Factors
Primary problem: Human Factors

Narrative: We had just finished a part 91 flight for the company. We parked the airplane next to the company owned fuel farm for refueling. After deplaning the passengers and helping them get their luggage to their cars; I did a post flight walk around of the aircraft; then [the] First Officer (FO) and I turned our attention to refueling the aircraft. It being the weekend our maintenance personnel; who usually fuel the aircraft; were off duty. So that meant I; the Chief Pilot; and the First Officer (Director of Operations) were responsible for the refueling functions. The FO then took the single point fuel nozzle to the aircraft and hooked it to the fuel port. We conducted the pre-check valve test of the fuel system; closed the pre-check valves; and continued fueling the aircraft with 600 gallons of fuel. I stayed at the fuel pump to man the dead man switch to stop the fuel at 600 gallons. Then the FO unhooked the single point nozzle and I watched him holding the single point nozzle in one hand; replace the fuel cap with the other hand. Then I turned my attention to securing the fuel farm. The FO walked the nozzle back as I reeled the hose in. I then closed the door and locked it and walked into the hangar to complete some paperwork. Since I walked around the aircraft after landing I did not think it necessary to do the walk around again. We got in the plane; the FO shut the cabin door he got in his seat we started running our preflight check lists and started the engines. The FO got an IFR clearance to [destination airport]. We performed the taxi checklist; takeoff checklist; and received our release and departed ZZZ. Take off and initial climb was normal we made the left turn towards ZZZ VOR and we received authorization to climb and maintain 9000. As we climbed through 5000 I noticed a pitch change in the engine noise. Engine gauges read normal except for right Interstage Turbine Temperature (ITT) gauge which was 100 degrees higher then left ITT gauge. As I pulled the throttles back to maintain airspeed the odd sounding pitch noise changed and became more pronounced. The FO volunteered to go back and look at the engines through the cabin windows; upon his return he described damage to the right engine inlet. We elected to turn back to ZZZ and received permission to return via right or left turn. At this time we were level at 9000 feet I slowed the airplane to 200 knots; we were told to contact approach and on contacting approach we got a descent clearance to 5000 feet. I pulled the throttles back and started our descent; which is when the right engine started vibrating. The right engine vibration light came on. I elected to shut the right engine down. We [advised ATC] telling [them] that we had a precautionary engine shut down. Performed precautionary engine shut down checklist---engine vibration ceased as soon as engine was shut down. Landed without incident taxied to ramp; shut engine down; and performed after shut down checklist. Got out of the aircraft walked around to the right side of aircraft and noticed fuel door was open and the fuel cap was missing. We noticed severe damage to the fan blades on the right engine. The FO believed he had left the fuel door open; with the door open the cap came off in flight and went through the right engine. I believe this incident could have been prevented by me conducting my usual preflight walk around of the plane. I trusted that the FO had shut and closed the door; while my attention was drawn away by shutting down and securing the fuel farm. I believe the fuel door should have an associated annunciator light that indicates when it is not closed. But ultimately I should have done a walk around of the plane after it had been fueled and before we departed.




Synopsis: Cessna 560XL Captain reported that one engine failed during climb after ingesting a fuel cap.