Date: 201402
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Flight conditions: IMC
Weather elements / visibility: 2.5
Light: Daylight
Aircraft: B737-700
Operator: Air Carrier
Operating under: Part 121
Flight phase: Taxi
Reporter organization: Air Carrier
Reporter function: First Officer
Human factors: Other / Unknown
Second reporter function: Captain
Anomaly: Deviation / Discrepancy - Procedural Published Material / Policy; Ground Event / Encounter Object
Detector: Person Flight Crew; Person Ground Personnel
When detected: Taxi
Result: Aircraft Aircraft Damaged; Flight Crew Became Reoriented; General Flight Cancelled / Delayed; General Maintenance Action
Contributing factors: Human Factors; Procedure; Weather
Primary problem: Ambiguous

Narrative: While parking the aircraft at the gate; with the nose wheel on the leading line and following Marshaller guidance; the Number 1 Engine Inlet Cowl contacted the jet bridge prior to reaching the stop bar. The Number 1 Engine Inlet Cowl was damaged. An aircraft logbook entry was made and Dispatch and Maintenance Control were notified.


Second narrative: While being marshaled into the Safety Zone at the gate; with the aircraft centered on the lead-in line; the Number One Engine Inlet contacted the jet bridge and was damaged. Following an uneventful ILS approach and landing in light snow; we taxied to the gate. All surfaces were covered in fresh; light snow obscuring most runway and taxiway markings. I approached the gate at a very slow pace (as the First Officer later described; 'slower than a walk'). Because we were early; I was anticipating the possibility of having to wait for a Marshaller. A Marshaller with wands was in place and had shoveled or plowed the lead in line for us. The lead-in line was the only marking clearly visible on the ramp. There was no equipment adjacent to the Safety Zone; no hoses or cables in the Safety Zone and; from our perspective; the jet bridge appeared to be in the correct location. We both verbalized that the safety zone was clear and I turned on to the lead in line; continuing the very slow pace. I noticed that the snowfall had changed to very large flakes and made a comment about it. I checked the braking action and said braking was 'GOOD.' Continuing down the lead-in line; I remained focused on the Marshaller with the snow falling. As we neared the jet bridge; its location did not strike me as unusual as it was sufficiently offset to my left. In my peripheral vision; I noticed an additional Ramp Agent approaching from the right. I secured the Number Two Engine and verbalized doing so. (At the time I thought the requirement was for braking action to be GOOD; which we had.)  Shortly thereafter; we felt a slight thump and the aircraft stopped. I did not notice any jet bridge movement and the Marshaller was still signaling forward taxi; now with more vigor since we had stopped. I verbalized 'that was not me; I think we are stuck in a rut.' I had just secured the Number Two Engine but I was hesitant to use a high power setting on Number One and did not push the power up. I noticed the Marshaller leaning to his right (my left); as if he was trying to see why we stopped and still signaling forward taxi. Something did not seem right. I set the parking brake and opened my sliding window to look out the left side to see what he was looking at (the L3 window was partially obscured with large snowflake accumulation). As soon as I saw the proximity of the jet bridge to the Number One Engine; I immediately shut down the engine. I then scanned the instruments for any signs of FOD ingestion. All indications were normal. The Marshaller never seemed to realize that we contacted the jet bridge. When I gave him the engine shutdown signal; he had a confused look on his face and did not acknowledge us. I left the parking brake set and we completed the engine shutdown flows and Parking Checklist. After completing the Parking Checklist I entered the cabin. The flight attendants were not aware that we had contacted the jet bridge but were concerned about its location for door opening. We only had four passengers and apparently none of them witnessed the contact. I explained that Ops was moving the jet bridge. We only had two local passengers and I was the first person off the aircraft because I too wanted to assess the damage. There was about an 8' x 3' puncture in the top leading edge of the engine inlet. I told the agent that the aircraft was out of service and requested a Ramp Supervisor. I never spoke with a Ramp Supervisor and never saw the Marshaller again so I do not know what he saw. The agent was visibly upset; crying; and stated that she thought the jet bridge was in the correct location. An individual with a SIDA badge and Airport Authority jacket was taking photographs from the jet bridge. He stated that 'his people' were working on the lights in the jet bridge and left it extended but had told 'someone' about it. I was later told by another agent that the previous aircraft on the gate was a 737-700 (same type-series as ours) and it was normal for the agent to assume it was in the correct position.I realize now that the jet bridge was angled out of the Safety Zone normally but then extended by the electrical workers into the Safety Zone. From our vantage point this did not appear unusual. Our jet bridge configurations throughout our system are quite variable. Additional factors were the thin snow covering that obscured most ramp markings; including the engine ingestion zones and the Safety Zone outlines. The snow coverage is not an unusual sight at any of our stations in the Midwest or Northeast this winter. As we approached the gate area; I verbalized that it was a nice surprise that someone had actually cleared the lead-in line for us. I am not aware of the agent's responsibilities for pre-positioning the jet bridge. I can only assume that she thought the jet bridge was in the correct location because of the last aircraft and again the lateral offset looking correct. I am not sure if she was aware that electrical workers had reportedly extended the jet bridge.


Synopsis: B737-700 flight crew describes the circumstances leading up to the left engine contacting the jet bridge during parking under a marshall's direction. The jet bridges position had been changed by airport workers doing maintenance and new snow obscured the ramp markings.