Date: 202012
Local time of day: 0001-0600
Location: ZZZ.Airport, US
Flight conditions: Marginal
Aircraft: Commercial Fixed Wing
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Cargo / Freight / Delivery
Flight phase: Taxi
Aircraft component: Wingtip
Component problem: Improperly Operated
Reporter organization: Air Carrier
Reporter function: Other / Unknown
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Human factors: Communication Breakdown; Situational Awareness; Troubleshooting
Anomaly: Aircraft Equipment Problem Critical; Ground Event / Encounter Object
Detector: Person Flight Crew
When detected: Taxi
Result: Aircraft Aircraft Damaged; Flight Crew Returned To Gate; General Flight Cancelled / Delayed; General Maintenance Action
Contributing factors: Environment - Non Weather Related; Aircraft; Human Factors; Procedure
Primary problem: Ambiguous

Narrative: I was assigned to and present aboard a deadhead flight. I opted to occupy the center jumpseat of the cockpit for taxi and takeoff. The push-back and start-up from the parking spot at ZZZ were uneventful.After completion of the Before-Taxi Checklist; the Captain began a taxi to the southwest; along the ramp; in accordance with marshaller's instructions. At the southwest end of the ramp was a wing-walker with lighted-wands; and several other employees. As the plane approached the southwest end of the ramp; the wing-walker and other ground personnel passed out of my field-of-view and were not visible to me for the duration of the taxi; due to the visibility limitations of the jumpseat.The Captain then began the 180-degree right turn denoted by the ramp taxiway centerline. At the Captain's request; the First Officer monitored the right wing during the turn. Upon completion of the 180-degree turn; the aircraft appeared (from the jumpseat view) to be located on or near the centerline of the ramp taxiway. The Captain then requested the First Officer verify that the right wing was clear of obstacles. The First Officer turned his head far enough to the right to see the wingtip of the aircraft. He responded that the wing was clear; and that he had the wing-walker in sight.The Captain then began a left turn towards Taxiway F. The Captain's focus was on the turn. The First Officer monitored the aircraft which was giving way to us; as we [exited] the ramp. (The aircraft was approaching from the opposite direction; with its taxi-lights on; however; it had been stationary for several minutes prior to this point.) Passing through 20 degrees of left turn; a shudder was felt in the cockpit; similar to heavy braking.The Captain immediately brought the aircraft to a stop. All three of us in the cockpit made a visual inspection of the aircraft (from the cockpit.) The cause of the shudder was not readily apparent. At my request; the Captain checked the Main Body Gear Steering indications on the EICAS; to verify it was not the cause of the shudder. At that moment; (deadheading) Captain [Name] entered the cockpit and advised us that the right wingtip had separated from the aircraft.The Captain proceeded to start the APU; shut-down the engines; configure the aircraft for towing; and make contact with the ground crew. After the damage was inspected by ground [personnel]; a tow vehicle was connected. The aircraft was towed back to the parking spot; where the cargo was off loaded and the aircraft turned over to maintenance [personnel] for inspection.Immediately following the events described above; the right wingtip was discovered on the ground; adjacent to a ramp lighting tower located on the southwest end of the ramp. (This tower had passed off the right wing during the right 180-degree turn required to exit the ramp.) Ground personnel reported that the Tower appeared to have damage; in addition to the aircraft's own damage.Shudder notice after contact with obstacle.Inadequate ramp space/clearance from obstacles.Ramp space and access points need to be verified for sufficient obstacle clearance prior to operating at such location.




Synopsis: Air Carrier Jump Seating Pilot reported the aircraft hit a light pole while exiting the ramp area.