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|
Attributes | |
ACN | 1310398 |
Time | |
Date | 201511 |
Local Time Of Day | 1801-2400 |
Place | |
Locale Reference | ANC.Tower |
State Reference | AK |
Environment | |
Flight Conditions | IMC |
Light | Night |
Aircraft 1 | |
Make Model Name | Widebody Low Wing 3 Turbojet Eng |
Operating Under FAR Part | Part 121 |
Flight Phase | Final Approach |
Route In Use | Other Instrument Approach |
Flight Plan | IFR |
Aircraft 2 | |
Make Model Name | Widebody Low Wing 3 Turbojet Eng |
Operating Under FAR Part | Part 121 |
Flight Phase | Final Approach |
Route In Use | Other Instrument Approach |
Flight Plan | IFR |
Person 1 | |
Function | Local |
Qualification | Air Traffic Control Fully Certified |
Experience | Air Traffic Control Time Certified In Pos 1 (yrs) 12.4 |
Events | |
Anomaly | ATC Issue All Types Conflict Airborne Conflict Deviation - Procedural Clearance Deviation - Procedural Published Material / Policy Inflight Event / Encounter Weather / Turbulence |
Narrative:
Aircraft X was on a 2 mile final. Aircraft Y was 4.5nm in trail. Weather was MVFR at the time with fog in the area that was obscuring the approach end of both the finals. Spacing collapsed to 3.95 nm prior to aircraft X reaching the runway threshold. I cancelled aircraft Y's approach clearance and instructed him to fly runway heading and climb to 3000 feet. Aircraft Z had departed runway heading. Before I could instruct aircraft Z to make an early right turn out to avoid possible wake turbulence from aircraft Y; the tower supervisor instructed me to turn aircraft Y to a 200 heading and to climb to 2500 feet. I complied with the instructions which then placed aircraft Y in confliction with aircraft a who was 4 nm south of the airport climbing out. I then gave aircraft Y traffic and continued his turn to a heading of 210 degrees. Although there was no loss of separation between aircraft Y and aircraft a; they came within 3.1nm laterally of each other.meanwhile; the field had gone below basic VFR with a ceiling of 400 feet broken. I had previously advised the final controller that we could not provide visual separation between arrivals due to the fog in the vicinity and that it was questionable as to whether aircraft could maintain visual separation from each other. I then advised that the weather was below basic VFR. A few minutes later; she transferred control of aircraft B; a VFR aircraft; that was 4 nm southwest of the field and was inbound. I immediately advised the aircraft that the field was below basic VFR and to maintain VFR and turn right southbound. I then called TRACON and advised that the aircraft was coming to them for resequencing. Additional contributing factor was that this incident occurred during the midday arrival push and that the arrival rate seemed to have been exceeded; especially with the existing weather conditions. The TRACON needs to provide more spacing between arrivals to the same runway when airport conditions are less than optimum. It seems that the majority of the controllers in the TRACON do not properly understand the concept of runway acceptance; especially with heavy jet aircraft; and with less than optimum weather and/or runway conditions. The tower supervisor; although trying to be of assistance; caused one problem to develop into another by not first checking with me to see what my plans were. TRACON supervisors need to slow the arrival rate when there are adverse weather conditions present.
Original NASA ASRS Text
Title: Two aircraft on finals' spacing deteriorated to less than required wake turbulence spacing resulting in the Local Controller issuing a go around. The Tower Supervisor instructed the Controller what control instruction to issue to the go around. The Supervisor's instruction placed the go around traffic into confliction with additional traffic the Controller was working. The Controller took action to resolve this confliction with no loss of separation.
Narrative: Aircraft X was on a 2 mile final. Aircraft Y was 4.5nm in trail. Weather was MVFR at the time with fog in the area that was obscuring the approach end of both the finals. Spacing collapsed to 3.95 nm prior to Aircraft X reaching the runway threshold. I cancelled Aircraft Y's approach clearance and instructed him to fly runway heading and climb to 3000 feet. Aircraft Z had departed runway heading. Before I could instruct Aircraft Z to make an early right turn out to avoid possible wake turbulence from Aircraft Y; the tower supervisor instructed me to turn Aircraft Y to a 200 heading and to climb to 2500 feet. I complied with the instructions which then placed Aircraft Y in confliction with Aircraft A who was 4 nm south of the airport climbing out. I then gave Aircraft Y traffic and continued his turn to a heading of 210 degrees. Although there was no loss of separation between Aircraft Y and Aircraft A; they came within 3.1nm laterally of each other.Meanwhile; the field had gone below basic VFR with a ceiling of 400 feet broken. I had previously advised the Final Controller that we could not provide visual separation between arrivals due to the fog in the vicinity and that it was questionable as to whether aircraft could maintain visual separation from each other. I then advised that the weather was below basic VFR. A few minutes later; she transferred control of Aircraft B; a VFR aircraft; that was 4 nm southwest of the field and was inbound. I immediately advised the aircraft that the field was below basic VFR and to maintain VFR and turn right southbound. I then called TRACON and advised that the aircraft was coming to them for resequencing. Additional contributing factor was that this incident occurred during the midday arrival push and that the Arrival Rate seemed to have been exceeded; especially with the existing weather conditions. The TRACON needs to provide more spacing between arrivals to the same runway when airport conditions are less than optimum. It seems that the majority of the controllers in the TRACON do not properly understand the concept of runway acceptance; especially with heavy jet aircraft; and with less than optimum weather and/or runway conditions. The tower supervisor; although trying to be of assistance; caused one problem to develop into another by not first checking with me to see what my plans were. TRACON Supervisors need to slow the arrival rate when there are adverse weather conditions present.
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.