Date: 202012
Local time of day: 1201-1800
Location: GSO.Airport, NC
Aircraft: Commercial Fixed Wing
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Taxi
ATC / advisory: Ground GSO
Reporter organization: Air Carrier
Reporter function: Pilot Not Flying; Captain
Reporter qualification: Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Human factors: Confusion; Situational Awareness
Second reporter function: First Officer
Anomaly: Deviation / Discrepancy - Procedural Clearance; Ground Event / Encounter Ground Equipment Issue; Ground Incursion Taxiway
Detector: Person Flight Crew
When detected: Taxi
Result: Air Traffic Control Issued New Clearance; Flight Crew Became Reoriented; Flight Crew Requested ATC Assistance / Clarification
Contributing factors: Airport
Primary problem: Airport

Narrative: We were given taxi instructions from the gate at GSO to Runway 23L via Kilo; K6; with expected delays due to traffic into ZZZ. We taxied down Kilo; but the sign for K6 was located 'after' the intersection of Kilo and K6 (not before); so we continued past the intersection; and then saw the late sign for K6. We stopped and asked ATC if we had in fact gone past K6; which they confirmed but said 'no problem'. We asked and received permission to taxi forward on Kilo and execute a 180 degree turn at the taxiway near the entrance to the cargo ramp; which GSO Ground approved; then taxied down Kilo again to K6; and waited for our flow time to ZZZ. The problem could have been easily avoided if the taxi intersection sign had been placed ahead of the K6 intersection (facing towards K5 vs. the cargo ramp); instead of after the intersection.I would suggest that the taxiway K6 sign be placed 'before' the intersection of Kilo and K6; so that a pilot taxiing down Kilo and looking for K6 would actually see it. Where it sits currently; past the actual K6 intersection; does no good to anyone; and is conducive to other pilots missing this intersection. A sign is cheap; compared to the potential problems.


Second narrative: During taxi at GSO we were taxiing to Runway 23L from the terminal via J3; K; and K6. We had passed taxiway K6 and continued straight on taxiway K. During the time we passed it; I was running the before takeoff checklist where I tried being outside of the airplane but the entire checklist is verifying the inside components are set and completed. The sun was also glaring in from my right side due to its position where I was partially blinded through the whole taxi even with sunglasses on. When I completed the checklist I looked up and saw the approach light systems for Runway 23L and looked behind and saw we missed K6. I advised Ground that we missed K6 and asked if we'd be able to make the turnaround we told them we'd have to wait until we were at the end and the Captain said we were able to so they said continue back K to K6 hold short Runway 23L. The Captain told me the sign for K6 is also after the taxiway and if you don't see that there isn't a taxiway past the sign it's already too late because you have to continue straight on K. When we taxied back; I wasn't able to confirm what sign was before K6 intersection. [Causes of the incident include] running the before takeoff checklist; sun glare on my side of cockpit; and the possibility that the K6 sign is after the taxiway. This was the last leg of a 4 day trip.


Synopsis: Air carrier flight crew reported the positioning and location of a taxiway sign K/K6 was confusing; which resulted in a taxiway incursion at GSO airport.