Date: 201603
Local time of day: 0601-1200
Location: AGC.Airport, PA
Flight conditions: VMC
Weather elements / visibility: 10
Light: Daylight
Aircraft: Light Transport; Low Wing; 2 Turbojet Eng
Operator: Air Taxi
Operating under: Part 135
Flight plan: IFR
Mission: Passenger
Flight phase: Taxi
ATC / advisory: Ground AGC
Reporter organization: Air Taxi
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument
Human factors: Situational Awareness; Distraction; Fatigue; Confusion
Second reporter function: Pilot Not Flying; First Officer
Anomaly: Deviation / Discrepancy - Procedural Clearance
Detector: Person Flight Crew
When detected: Taxi
Result: Air Traffic Control Issued New Clearance; Flight Crew Became Reoriented
Contributing factors: Airport; Human Factors
Primary problem: Human Factors

Narrative: This event was a situation that almost led to a runway incursion. Myself and the SIC had a very early start to the day (4am show) and are not a crew that normally flies together. These may have nothing to do with the incident; but both are worth noting. We had a position leg to AGC where we picked up passengers at the FBO. We received a clearance to taxi to RW28 via Taxiway Alpha and had been cleared to cross RW13-31. An airplane was taking off on RW28 as we were taxiing. We were the only two aircraft on the airport in motion. I am unsure whether ground and tower were combined on the same frequency. We have Jepps built into the avionics on our aircraft and the appropriate airport diagram was displayed with the aircraft depicted at the time. As we exited; I taxied perpendicular to Taxiway Alpha; so as not to shortcut across the ramp. As we approach Alpha; we never saw a sign for Alpha and actually taxied unknowingly onto A3. We had mistaken RW13-31 for taxiway A. As we approached runway RW13-31; we realized our error and stopped the aircraft short of Runway 13-31. This took place at the A3 taxiway. Because of A3's close proximity to the runway and the ground controller's lack of knowledge of our intent to stop; he instructed us to stop. At that time we were almost at a complete stop. We never crossed onto the runway until we were cleared to taxi on it afterwards. This was all located in a Hotspot on the diagram (HS1). I feel that when I became convinced that runway 13-31 was the taxiway that I was looking at; I became fixated on this and did not take heed from the rest of the information that I had to use. We did not brief the hotspots before or during the taxi; which now seems like a prudent thing to do. The lack of delineation of ramp to taxiway also contributed to my confusion. Nowhere is there any signage to show taxiway A from the direction that I came. The fact that I chose to take the perpendicular route to the taxiway still seems to be a prudent thing to do; but added to my fixation on the taxiway. Looking at the diagram it seems like this would not be possible; but I am afraid it was. In addition; the fact that the SIC had his head down for part of the taxi; to read a checklist; contributed to the confusion once he looked up. He had to reevaluate our current position and figure out what my intentions were. Also the fact that we both were not paying 100% attention to the taxi; while operating in close proximity to a runway; took away the doubling checking that would have been there if we had both been paying attention.


Second narrative: After accomplishing the After Start Checklist we proceeded with a right turn out of the ramp area. Once headed in the correct direction I commenced reading the Taxi Checklist items and shortly thereafter heard over the radio to STOP. We had inadvertently crossed through taxiway alpha and onto A3 headed for Runway 31.A3 is approximately 20 feet long in length and is where we came to a stop. At no point did the aircraft cross the hold short lines onto Runway 31. The visual perception as you approach Alpha from afar is that Runway 31 or 28 could be taxiway Alpha. This entire area is noted as a Hot Spot area on charts. I feel that a combination of where you exit this particular ramp from along with constricted taxiways and runway intersections can be visually misleading.


Synopsis: Light transport flight crew taxied onto Taxiway A3 towards Runway 13-31 at AGC after mistaking the runway for Taxiway A.