Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 3
Situational Awareness; Distraction; Troubleshooting; Workload; Confusion
ATC Issue All Types; Conflict Airborne Conflict; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance
Air Traffic Control Issued New Clearance; Air Traffic Control Provided Assistance; Flight Crew Returned To Clearance
Procedure; Staffing; Human Factors
I was working CIC (Controller In Charge) at the time of the event. It was the [late morning] departure push; and I had opened the second ground control (GC) in anticipation of over 100 operations in the coming hour. Aircraft X had exited 28L at Tango; LC (Local Control) then crossed Aircraft Y and Aircraft Z on Twy T and K; respectively. I watched all three aircraft come to a stop in the K/T/B intersection; with Aircraft Y and Aircraft Z unable to clear 28L. GC1 (Ground Control) was very busy with several aircraft without gates; numerous outbounds and the added complexity constraint of having part of Twy Zulu closed; necessitating complex staging to having repositioning aircraft cross the 28s. I walked over to LC and told him to send Aircraft A around; which was on short final Rwy 28L. LC had a southbound VFR transition; Aircraft B in the missed approach corridor; so myself; LC and LCA were watching that to ensure the missed approach and the transition were separated; I was also continuing to watch when 28L became clear from the previous arrivals that had stopped. The controller being relieved at GC2 noticed the non-acquisition in the upwind for the 1s. At this point I had stepped back to start logging the missed approach. I looked at the radar and initially thought there was only one target; since they were so close together; in fact; neither of the departures (Aircraft C and Aircraft D) had acquired. I was monitoring LC and not RC; so I did not hear the coordination between LCA and CI-1. LCA and LC had difficulty discerning which aircraft was which. LC first reiterated the departure procedures that each aircraft should have been on. He then instructed Aircraft C to turn right 30 degrees; which that aircraft did not acknowledge until the second time LC issued the turn. At no point did the STARS Conflict Alert sound with the two upwind departures.I could have kept CD (Clearance Delivery) open to have an extra set of eyes in the tower. However; that person had already worked for an hour; would have needed a break during this push anyway (otherwise would have exceeded 2 hours time on position); and there was no one else coming up from their break due to our short staffing. I could have suspended transitions at the beginning of the departure push; which would have precluded the go-around traffic conflict in the air with the Aircraft B from occurring; and hopefully would have meant someone would have seen the upwind departure conflict sooner. Ultimately it's up to the pilots to fly their planes. They should not be so dependent on their cockpit automation that they don't notice themselves that the aircraft turned left on departure instead of right; as per the SID. The old adage I learned in flight training applies here: Aviate; Navigate; Communicate. It appears the pilots of Aircraft C didn't do any of those three things very well. Had the STARS CA sounded with the upwind pair; perhaps someone would have noticed what was happening sooner. Overtime should have been scheduled or assigned to provide adequate facility staffing.
I was monitoring GC2 during the post position relief briefing. I noticed that LC had crossed Runway 28 Left at T and K with an aircraft having just exited at T from Runway 28 Left. The next arrival was Aircraft A about a mile and a half final. I leaned over to LC and said watch the intersection of T and K at B as the aircraft probably would not clear. Very quickly after LC looked in the direction; the CIC came over and said to send Aircraft A around that it would not work. Next; while watching Aircraft A climb out; I noticed a non-acquisition on a Runway 1 departure. I leaned over in between LC and LCA as as I said 'no tag'......I added an 's' to make it plural. There were two untagged targets right on top of one another; and as I brought this up; LC started to tell Aircraft C they were supposed to be on the TRUKN SID turning right. I did not hesitate and said as clearly as I could 'Turn Aircraft C right heading 040 and say immediately.' The Local Controller did so. Then a moment later they said to turn right heading 030. The aircraft began diverging at this point and I left the tower cab as my overlap was complete. This was the worst loss of separation I have personally witnessed as I do not imagine Aircraft C saw Aircraft D; but had a TCAS RA event; as they leveled at 1600 feet for quite a while; while directly underneath and that may very well be the only reason they did not physically collide. I spoke to the Local Controller post event downstairs and suggested that if something like this were to happen again; separate the airplanes first then explain that the aircraft should have been on a different course for the SID they are on.
SFO Tower controllers reported a loss of separation. One of the reporters told the Local to turn one of the aircraft to get them separated.