B757 Undifferentiated or Other Model
Air Traffic Control Fully Certified
Situational Awareness
ATC Issue All Types; Deviation / Discrepancy - Procedural Published Material / Policy
General None Reported / Taken
Airspace Structure; Procedure; Human Factors
I was vectoring for staggered ILS approaches. My attention was drawn to a situation where the other Final Controller (training) was extremely late turning into a gap and I was trying to make that work. When I looked to my other traffic I saw the two aircraft coming together at a rapid rate. I felt the base leg traffic that had been descended to 6;000 feet had not been descending at a standard rate and didn't help the situation. I turned him hard right immediately and turned the Airbus 319 hard left and tried to descend as it almost appeared the CRJ-200 had leveled. They both had at this point started into a TCAS maneuver. It gave me one hell of a scare! Meanwhile; I still had the other aircraft on the final high on the glide slope because of the original problem; who eventually had to come out to get re-sequenced. This was a classic case of being distracted by something and a couple normal things end up getting away from you and causing a big mess! I was not happy with the trainer allowing his trainee to contribute to this when he could have; and should have; taken over and taught the trainee how to work as a team to work out a situation. A simple descent for a visual approach would have done that. That being said; I take responsibility as I always have for my actions and for my part in this.There has been much discussion that on the high side (b) you have to level at 7;000 feet because of an airspace boundary which is the base leg altitude as well. So in order to get aircraft down it is very common to use 7;000 feet as a short gap...when on the (a) side you have airspace to descend. We should have airspace on both sides to avoid people constantly having to point out or put themselves in jeopardy of these type things happening. I have already spoken to my Supervisor about this being a training (lessons learned) tool for the TRACON as we have many new feeder and final controllers who may learn from this scenario.
TRACON Controller described a loss of separation event during staggered ILS approaches; listing distractions and training as contributing factors.