Date: 201709
Local time of day: 0601-1200
Location: PHL.Tower, PA
Aircraft: Large Transport
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Taxi
ATC / advisory: Ground PHL
Second aircraft: Large Transport
Reporter organization: Government
Reporter function: Ground
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Communication Breakdown; Workload; Confusion; Situational Awareness; Distraction
Second reporter function: Pilot Flying; First Officer
Anomaly: ATC Issue All Types; Conflict Ground Conflict; Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Clearance; Ground Incursion Runway; Ground Incursion Taxiway
Detector: Person Air Traffic Control
When detected: Taxi
Result: Air Traffic Control Issued New Clearance; Air Traffic Control Issued Advisory / Alert; Flight Crew Became Reoriented; Flight Crew Executed Go Around / Missed Approach; Flight Crew Requested ATC Assistance / Clarification
Contributing factors: Airport; Chart Or Publication; Company Policy; Human Factors
Primary problem: Human Factors

Narrative: I was working Ground Control sectors combined; moderate to heavy traffic. There was a disabled aircraft on the primary arrival runway. As a result arrivals were landing on the primary departure runway; increasing the workload for both myself and the local east controller. Adding to the complexity of the situation were several similar call signs among proposed departure aircraft. Air Carrier X called for taxi; but called himself Air Carrier Y. I issued instructions to Air Carrier Z; believing it to be the correct call sign; and Air Carrier X responded. Hearing the read back with the correct call sign; I realized I needed to replace the misposted Air Carrier Z strip from local east's bay with the correct Air Carrier X; correct the strip marking; remove the incorrect Air Carrier Z from taxi status in the Departure Sequencing Program (DSP); and put Air Carrier X into taxi status.Workload increased significantly at this point as I attempted to continue responding to other departures while correcting the issues caused by the call sign mixup. Shortly after these events; Air Carrier A called at spot 2 and I issued instructions to taxi 'Runway X via Juliet; Yankee; Kilo' and verified that the pilot had his weight and balance numbers and would be ready for departure; as this was a very short taxi. He said he was ready and I instructed him to monitor tower. There were at least two similar call signs also proposed for departure; I cannot recall the exact numbers. Shortly after taxiing Air Carrier A; I realized that once again I had put the incorrect flight plan into taxi status and posted the wrong strip; this time for Air Carrier B instead of Air Carrier A as I had intended. This time the mistake was entirely my own; as I had simply taken the wrong strip out of my bay. Once again; my workload spiked as I retrieved the incorrect strip from local east's bay; replaced it with the correct strip; marked it appropriately; removed the incorrect Air Carrier B from taxi status; put Air Carrier A into taxi status; and quickly reviewed the flow control program to make sure I wasn't missing anything. While I was accomplishing these tasks; I did not see that Air Carrier A missed the eastbound turn onto the wrong taxiway continuing south and across the runway approach safety area. Two other members of the tower team spotted the conflict with an arrival short final and shouted warnings to Local Control. I began calling out to Air Carrier A; on the chance that he had not switched to tower yet; but got no answer. Local Control sent the arriving aircraft around; but it appeared to overfly the taxiing Air Carrier A on short final.The Yankee/Kilo/Whiskey area is one where we often see pilots take wrong turns or fail to turn when they should; often taxiing right past the end of the runway or crossing the runway approach on Yankee. A contributing factor worth noting is that without numerous similar call signs among [Air Carriers]; I would have had more time to scan out the windows and I feel I would have been more likely to spot and stop Air Carrier A's incursion. [This company] often assigns very similar call signs to aircraft which are not only proposed at the same time; but many times will fly to the same parts of the country and therefore potentially cause issues for multiple controllers as they fly similar or identical routes. Seeing three or four call signs which can all be easily confused for each other is common during departure pushes and even vigilant pilots and controllers fall victim to the resulting confusion routinely. It's a contributing factor that should be removed from the equation. I firmly believe that had I not been preoccupied with sorting out the [similar call sign] confusion; I would have been able to keep a more efficient scan; catch Air Carrier A miss his turn; and prevent an overfly event.


Second narrative: [Report narative contains no additional information.]


Synopsis: A Tower Ground Controller and flight crew reported an aircraft missed a turn while taxiing and entered the runway approach safety area with an arriving aircraft on short final.