2023-06 · NASA ASRS report 2008059
Two Center Controllers and an Operations Manager reported an aircraft on approach was not in communication due to being issued a frequency which was out of service. The aircraft descended below the Minimum IFR Altitude and was in conflict with an adjacent airport departure and other VFR aircraft in its path. The Center assumed airspace from the TRACON due to TRACON radio site outage even though the Center Controllers had no training on the procedures for the airspace.
I was working Sector X. Our main frequency site failed; all of ZZZ TRACON Northern Airspace transmitters also failed. Despite that fact that neither of us could talk to airplanes effectively or safely we once again absorbed the Northern Airspace from ZZZ Approach. On [Sector] X I was using the east side frequency site and we had taken secondary frequency from Sector Y and were using it for lower aircraft near ZZZ TRACON in the Northern Airspace. secondary frequency was working better for the most part so I put all of my aircraft on it. ZZZ Airport was busy with arrival and departure traffic; and Sector Z was flashing a ZZZ1 Airport lander at me.My D-side released Aircraft X off of ZZZ Airport and climbing to 12;000 ft. I quickly got him radar identified in order to prevent non-radar separation issues and continued working. ZZZ Airport put him on frequency. I then climbed Aircraft Y; a ZZZ departure on secondary frequency. I had been intermittently teaching myself the ZZZ1 Airport arrival procedures and was trying to figure out how I was going to get him in with a ZZZ Airport arrival coming out and a departure coming it. I have no training in this scenario nor have I encountered it. My plan was to make the ZZZ1 Airport arrival shoot a Visual Approach even though he was requesting the GPS (with Sector Z) and also have the ZZZ Airport arrival shoot a Visual Approach. I believe that would have been legal with the airports far enough apart from each other but I have no idea. I'm not trained in the separation of traffic in that airspace at all nor the intricacies of non-radar separation rules in that confined of a space. I was never able to execute this plan.Sector Z indicated to me that he inadvertently put Aircraft Z on frequency and that I should try and relay to him. I had no idea if I could talk to him; I tried to make a broadcast to him and figured I would try him a few times; get a hold of him and get him on secondary frequency. This never happened; apparently after trying me and failing to reach me; Aircraft Z switched to CTAF. Prior to reaching the IAF for the GPS approach into ZZZ1 Airport; Aircraft Z began descending. I saw this; and reached out to Aircraft Y to get him to try and relay a low altitude alert to Aircraft Z. He could not reach Aircraft Z. I got him to switch to frequency and had him reach out with another low altitude alert for Aircraft Z. He got no response. I moved him over to the ZZZ1 Airport CTAF and had him relay another low altitude alert. He finally got in contact with the aircraft. At this point all communications between me and Aircraft Z were via a relay through Aircraft Y. I never spoke to that aircraft and still have never spoken to that aircraft.After the low altitude alert relay; during the process of trying to figure out what Aircraft Z was doing he began [conflict alert] flashing with 3 aircraft near the IAF. I had issued traffic alerts to be relayed to him interrupting my questions. After he passed those aircraft he turned to the airport; at this point about 10 miles away and I still had no idea what he was doing. Aircraft Y gave me a relay from him I didn't understand. At that point he was close to the airport and I tried to just clear him for the approach. During the numerous safety alerts I failed to research an arrival I've never issued and missed that the missed approach altitude was 12;000 ft. I had a ZZZ Airport departure overhead at 12;000 ft. At this point; this guy had almost dived into terrain and had almost run into 2 to 3 other aircraft because he decided he was cleared for the approach and switched to CTAF on his own so I tried to get Aircraft Y to issue a brasher warning. Before Aircraft Y could relay the brasher he relayed a cancellation to me and as Aircraft Y was issuing the brasher; an aircraft departed ZZZ1 Airport opposite direction and I had Aircraft Y interrupt the brasher to call yet another traffic alert to Aircraft Z. They had 0 miles of separation and 2-3 hundred ft. by the time they passed. This practice is going to result in the loss off life; someone will eventually die and it will be the FAA's fault for not doing anything to fix the problem. This is the worst situation I have been involved in with the Northern Airspace but I have already submitted numerous reports about how stupidly unsafe these practices are and nothing is being done to fix them. The reliability of the Northern Airspace radio sites and of our west side frequency site is not acceptable; fix them immediately regardless of the cost. Northwest controllers are not trained to work the Northern Airspace. Northwest [ZZZ Center] controllers are not certified to work the Northern Airspace. Northwest controllers have no experience working the Northern Airspace. Northwest controllers should never take the Northern Airspace from ZZZ TRACON. The practice is not safe; stop doing it; come up with a better plan. If this is the only plan; fly us to ZZZ TRACON and have us certify on working the Northern Airspace like any other sector. Its too busy and too complex to work under the best conditions and we always have to take it after our main radio transmitter site fails. THIS IS NOT SAFE. If the Northern Airspace radio sites fail; call ATC-0 until better procedures are implemented. Stop forcing me to work airspace I don't know using procedures I haven't been trained on using radio's that don't work. I can't think of a way to say this stronger.
At XA:00; Sectors Z and X lost the ZZZ Airport Remote Communications Air to Ground (RCAG) which also impacted ZZZ TRACON's Northern Airspace. ZZZ TRACON went ATC alert and gave the airspace back to ZZZ Center due to the RCAG outage. Unfortunately; ZZZ Center also uses that site and without the ZZZ Airport site; ZZZ Center has radio coverage gaps. As the OM; I was alerted to the outage by the SOC at XA:05. The radio outage forces ZZZ Center to relay to aircraft which is not ideal at all. It seems that the ZZZ Airport RCAG site has failed several times recently which creates this unsafe situation where ZZZ TRACON and ZZZ Center now have radio coverage gaps. The following MIA violation was a direct result of the ZZZ Airport RCAG coverage gaps.Sectors Z and X; lost the ZZZ Airport RCAG site and could not talk to Aircraft X who was eastbound at 11;000 ft. landing ZZZ Airport. At XB:06; Aircraft X started a descent without a clearance and violated the 10;000 ft. MIA polygon. The pilot descended to 9;700 ft. before he was established on the ZZZ Airport GPS RWY XX approach. The pilot had not been cleared for the approach due to our communications issue. I would recommend a radio spectrum analysis of our radio coverage in and around the Northern Airspace for ZZZ Center and ZZZ TRACON. There needs to be adequate RCAG backups that cover the airspace and should not leave ZZZ TRACON and ZZZ Center with coverage gaps. There seems to be no redundancy for when the ZZZ Airport RCAG site fails.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.
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