Date: 201811
Local time of day: 0601-1200
Location: ORD.Airport, IL
Flight conditions: VMC
Aircraft: B737 Undifferentiated or Other Model
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Taxi
ATC / advisory: Ramp ORD
Reporter organization: Air Carrier
Reporter function: First Officer; Pilot Not Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Human factors: Distraction; Human-Machine Interface; Situational Awareness
Anomaly: Ground Event / Encounter Vehicle
Detector: Person Ground Personnel; Person Other Person; Person Passenger
When detected: Taxi
Result: Aircraft Aircraft Damaged
Contributing factors: Aircraft; Airport; Environment - Non Weather Related; Human Factors
Primary problem: Human Factors

Narrative: We were cleared into our gate by Ramp Tower. Turning from the Bravo line onto the lead-in line for our gate was a 90 degree left turn. We were taxiing at a slow speed due to the possible slick conditions; but the ramp conditions did appear to be 'good.' As we made the 90 degree left turn; I was scanning my area on the right side of the aircraft. There did not appear to be any obstructions; and the [company] system was giving us the appropriate guidance to proceed in. From my vantage point; I do not recall being able to see much of anything on the left side of the aircraft due to the 90 degree turn from the Bravo line.As we proceeded into the gate under the [company] guidance with my feet resting on the brakes; I do not remember us ever receiving an alert to 'slow down.' I also don't recall the [company] advising us to correct left or right on the lead-in line. At no time did I see the [company] system indicate there was an 'obstruction' nor did the system advise us to 'stop.' Within approximately 3 feet from where the [company] wanted us to stop; we felt a skid or a slide. We continued forward a couple more feet and the [company] system told us to 'stop.' The [company] then said; 'too far.' I recall the Captain saying something to the effect of 'Well no kidding we're too far we were sliding.' He then said; 'I have no idea what that was.' I said; 'it felt like we slid on the lead-in line paint. I slide on that paint every time I do a walk around in the winter.' He said; 'It felt like we ran over a clump of ice or something.' We proceeded to shut down the aircraft and run the Parking Checklist.As I was gathering my belongings a ramp agent came into the flight deck and said something like 'Did that truck just run into you guys'? I said; 'What'? Then I thought; maybe that was the skid sensation we felt. I stepped off to look out the jet-bridge. I saw people around the wingtip and the truck. I then thought I better call the Captain to let him know a truck just ran into our wingtip. I overheard passengers saying a truck just hit our plane.I have not seen any video of the event. I was shown a picture of the scimitar winglet and debris on the ground. I am unable to conclusively determine if the truck was stationary; over the red line which indicates the protected zone; if the debris was moved; or if we taxied into the truck. The truck was moved before any of the people I spoke with could see it or take pictures of it. To my knowledge; no injuries were reported; and I don't believe the safety of anyone was ever in jeopardy.




Synopsis: B737 First Officer reported their wingtip came in contact with a service truck while parking at the gate.