An Anchorage Center Controller reported an aircraft transitioning from Oakland Center non radar airspace flew 30 minutes unidentified into Anchorage Center airspace without communications transfer or flight data information updated. The reporter states a flight strip to indicate the traffic was inbound was missing and several issues with CPDLC connectivity and airspace configuration are a recurring issue in this airspace.
Synopsis
An Anchorage Center Controller reported an aircraft transitioning from Oakland Center non radar airspace flew 30 minutes unidentified into Anchorage Center airspace without communications transfer or flight data information updated. The reporter states a flight strip to indicate the traffic was inbound was missing and several issues with CPDLC connectivity and airspace configuration are a recurring issue in this airspace.
Narrative
At XA:41z Aircraft X was transferred by ZOA (Oakland Center Oceanic) to cross the FIR (Flight Information Region) into Sector 69. The strips appeared to not have been marked and filed appropriately and as a result the aircraft had no data tag manually entered on the screen to indicate a non radar. The Sector 60 controller did not see the limited tag come in and the pilot (when he reached out via SAT phone much later) reported that he had not received any communication instructions from Oakland and was unable to get a response via CPDLC (Controller Pilot Data Link Communications) either. The aircraft was in the sector for close to 30 minutes without a code or communications as a result. No loss of separation was apparent.This is a known problem area for both non radar and communications and Data Link often cannot smoothly connect because of the dual ANC Center CPDLC addresses PAZA and PAZN. All of these issues easily led to the Aircraft X not being able to establish contact with ATC. The first issue of 'missing' the non radar strip has been reported several times as a systemic safety hazard. Work began on correcting with issue in 2018 and a resolution was proposed in November 2020 to isolate the coding (in that area) that already existed within Microearts (Microprocessor Enroute Automated Tracking System) to enable the auto track start functionality when a CPL is received from ZOA. This would be a visual indicator for the radar team of an incoming non radar aircraft. I do not know the status of the initial ticket; whether it is still pending or not; but should be followed up with automation.The second piece of this is the communication portion. We are unsure why the aircraft did not receive communication instructions via CPDLC from Oakland in this case; but often; depending on where they enter the FIR; the auto contact message for what frequency to use could easily be wrong. When the aircraft is flying through PAZN and in short succession into PAZA; the automatic NDA tries to send before the aircraft is even 'current' with the first and will not disconnect properly as a result. It could be true in the case of Aircraft X (though this is speculation on my part) that because he was in such close proximity (inside the expanded boundary of the oceanic airspace) that the NDA sent for PAZN first and then PAZA before the contact center message went out and as a result Aircraft X was unable to receive the uplink for comms from ZOA. If he was then never disconnected manually from the AFN window by the Oakland controller; that link would stay open and not allow Aircraft X to properly switch; which is why he was unable to get any response via his CPDLC request for a VHF frequency because it was 'hung up' behind him.I don't think that this issue will be fixable unless there is an airspace redesign for the 'corner' shared by Oakland; Sector 10; and Sector 68/69 which has also been discussed and presented in the past and I am unsure of the outcome of that at this time.
Second reporter narrative
I was made aware that during the last portion of my shift yesterday working as an A-side on the combined 63/68/69 (sec 68 in this event) there was a aircraft that was filed non-radar coming in from Oakland airspace that I did not recognize and handle as a standard non-radar strip. Later on after I was off sector the aircraft came into our airspace and proceeded for some time unidentified until recognized by another sector. I do not recall handling this aircraft but from the times in the logs the strips appear to have printed within the first few minutes of me getting onto the sector. Due to the nature of our airspace and how non-radars are transferred there is a bit of a trap built into these events if a strips entry fix is not recognized by the A side or whoever may be handling the strips then there is little to no fail safe in identification of an aircraft after they cross into the sector. This coupled by the aircraft potentially having not received/following appropriate comm instructions to contact ZAN after crossing their boundary point seems to be potential factor as well.It is my understanding that there has been a potential solution in the works for almost 2 years at this point that the plans and programs group has been in the loop on that would allow for these non radar targets to auto-populate a tag to help identify and draw attention to them when they cross into our airspace. I feel that this would be a great starting point to help alleviate issues like this from happening. Otherwise I will continue to try and pay closer attention to my own shortcomings to prevent my own role in its re-occurrence.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.