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|
Attributes | |
ACN | 1271114 |
Time | |
Date | 201505 |
Local Time Of Day | 1201-1800 |
Place | |
Locale Reference | ZAN.ARTCC |
State Reference | AK |
Environment | |
Light | Daylight |
Aircraft 1 | |
Make Model Name | Widebody Low Wing 2 Turbojet Eng |
Operating Under FAR Part | Part 121 |
Flight Phase | Climb |
Flight Plan | IFR |
Aircraft 2 | |
Make Model Name | Widebody Low Wing 2 Turbojet Eng |
Operating Under FAR Part | Part 121 |
Flight Phase | Climb |
Flight Plan | IFR |
Person 1 | |
Function | Enroute |
Qualification | Air Traffic Control Fully Certified |
Experience | Air Traffic Control Time Certified In Pos 1 (yrs) 22 |
Events | |
Anomaly | ATC Issue All Types Conflict Airborne Conflict Deviation - Procedural Published Material / Policy |
Narrative:
During the midnight shift there is generally a westbound push of aircraft that converge in the vicinity of snp all routed to join R220 or R580. With the increase in (upr) [user preferred route] flights and lack of restrictions on routing it is becoming increasingly more difficult to maintain a situational awareness of an aircraft's routing with the (atop) [advanced technologies & oceanic procedures] system and controllers are relying more and more on the system advising when there will be a separation issue. Atop works great for what it was designed for which is oceanic traffic using a procedural probe; but when using this system in domestic airspace where radar rules are being applied and there is not a probe the system shows it's weakness. This area around snp is where the transition happens to procedural separation for westbound aircraft and eastbound aircraft are transitioned to appropriate altitude for direction of flight enter domestic. This area can be an extremely highly congested area with traffic both east and westbound at all altitudes without a probe of any sort. Within domestic airspace; correct altitude for direction of flight is one additional and important layer to the swiss cheese theory to separate opposite direction traffic; but within the snp transitional area controllers would quickly run out of altitudes if unable to use (iafdof) [inappropriate altitude for direction of flight]. The near midair at sya late last year received extreme scrutiny and it was pointed out on many levels that this had been predicted to have a high probability of happening and was also submitted by the local safety council as one of the highest safety concerns in the facility several years ago. The sya area was recently fixed by turning on the procedural probe through this area but the likelihood of this same event happening again within the snp radar volume is just as high as it was at sya and is not being addressed. The reason for this report is a missed conflict of a northeast bound aircraft X at FL330 direct ort and a westbound aircraft Y at FL320 which was being sequenced into the westbound flow and climbed to FL340. In order to keep the data blocks from overlapping it is common to drag them away from the aircraft symbol which also makes it harder to do a traffic scan when there is a high congestion of aircraft in a small area and working on a 1900 mile scale. There were several aps's [aircraft position symbol's] superimposed which at the time I had thought all to be westbound but as the clearance was being issued for a climb to FL340 I realized the aircraft was in close proximity and had just passed tail to tail with the eastbound aircraft X flight at FL330. In this instance there was not a loss of separation but simply by chance this happened to be 5 miles tail to tail vs 5 miles nose to nose.atop has a great probe for procedural airspace but currently does not probe for radar separation. There have been several proposed solutions; one even having been written by lockheed; to be able to adapt atop to probe within surveillance airspace for surveillance separation but these changes are not in the foreseeable funding stream. With zan increasing the areas in which atop is being used to control traffic in domestic airspace and ZOA and ZNY incorporating more radar into their operations; developing a probe to work in surveillance airspace should be moved up the list to be funded.
Original NASA ASRS Text
Title: ZAN Controller reports of an almost operational error that happened just by luck. Controller was working both aircraft at the time but due to many Aircraft Position Symbols he climbed an aircraft that he should not have. Controller suggested that ATOP be able to predict conflicts in the terminal area and not just oceanic.
Narrative: During the midnight shift there is generally a westbound push of aircraft that converge in the vicinity of SNP all routed to join R220 or R580. With the increase in (UPR) [User Preferred Route] flights and lack of restrictions on routing it is becoming increasingly more difficult to maintain a situational awareness of an aircraft's routing with the (ATOP) [Advanced Technologies & Oceanic Procedures] system and controllers are relying more and more on the system advising when there will be a separation issue. ATOP works great for what it was designed for which is oceanic traffic using a procedural probe; but when using this system in domestic airspace where radar rules are being applied and there is not a probe the system shows it's weakness. This area around SNP is where the transition happens to procedural separation for westbound aircraft and eastbound aircraft are transitioned to appropriate altitude for direction of flight enter domestic. This area can be an extremely highly congested area with traffic both east and westbound at all altitudes without a probe of any sort. Within domestic airspace; correct altitude for direction of flight is one additional and important layer to the swiss cheese theory to separate opposite direction traffic; but within the SNP transitional area controllers would quickly run out of altitudes if unable to use (IAFDOF) [Inappropriate Altitude for Direction Of Flight]. The near midair at SYA late last year received extreme scrutiny and it was pointed out on many levels that this had been predicted to have a high probability of happening and was also submitted by the local safety council as one of the highest safety concerns in the facility several years ago. The SYA area was recently fixed by turning on the procedural probe through this area but the likelihood of this same event happening again within the SNP radar volume is just as high as it was at SYA and is not being addressed. The reason for this report is a missed conflict of a northeast bound Aircraft X at FL330 direct ORT and a westbound Aircraft Y at FL320 which was being sequenced into the westbound flow and climbed to FL340. In order to keep the data blocks from overlapping it is common to drag them away from the aircraft symbol which also makes it harder to do a traffic scan when there is a high congestion of aircraft in a small area and working on a 1900 mile scale. There were several APS's [Aircraft Position Symbol's] superimposed which at the time I had thought all to be westbound but as the clearance was being issued for a climb to FL340 I realized the aircraft was in close proximity and had just passed tail to tail with the eastbound Aircraft X flight at FL330. In this instance there was not a loss of separation but simply by chance this happened to be 5 miles tail to tail vs 5 miles nose to nose.ATOP has a great probe for procedural airspace but currently does not probe for radar separation. There have been several proposed solutions; one even having been written by Lockheed; to be able to adapt ATOP to probe within surveillance airspace for surveillance separation but these changes are not in the foreseeable funding stream. With ZAN increasing the areas in which ATOP is being used to control traffic in domestic airspace and ZOA and ZNY incorporating more radar into their operations; developing a probe to work in surveillance airspace should be moved up the list to be funded.
Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.