Date: 201705
Local time of day: 0001-0600
Location: SCT.TRACON, CA
Aircraft: B737 Undifferentiated or Other Model
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Final Approach
Airspace: Class B SCT
ATC / advisory: TRACON SCT
Second aircraft: B737 Undifferentiated or Other Model
Reporter organization: Government
Reporter function: Approach
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Human-Machine Interface; Situational Awareness; Time Pressure; Workload; Fatigue; Communication Breakdown; Confusion; Distraction
Second reporter function: Approach
Anomaly: ATC Issue All Types; Airspace Violation All Types; Conflict Airborne Conflict; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter Weather / Turbulence
Detector: Person Air Traffic Control
When detected: In-flight
Result: Air Traffic Control Issued New Clearance; Flight Crew Returned To Clearance
Contributing factors: Procedure; Human Factors; Staffing; Weather
Primary problem: Staffing

Narrative: I was working STADIUM/ZUMA combined. Busy traffic and was extended out with the base legs due to traffic volume and EMT IFR operations. While deciding my sequence for the final and where the downwind traffic would fit; I decided to put a previous Aircraft X down the localizer above the traffic and re-sequence that aircraft back in to the downwind to make a slot for the current downwind aircraft. If I had slowed Aircraft Y; I would close the hole behind and another behind that and my current downwind would be very out of position and out of my airspace before turning to the final. While accomplishing all of this; I looked farther out on the final at what aircraft were coming from Feeder sector. I noticed Aircraft Y on an 'F' tag (Feeder sector) and not flashing to me; but appeared cleared for the ILS to 24R (my runway and final). I was about to ask Feeder to ship Aircraft Y; but I heard the Feeder controller ship the aircraft. I then went back to focusing on my current aircraft due to the complexity of the situation. I asked for Aircraft Y twice. He didn't answer until my second ask; and then asked the pilot if he could see Aircraft Z on the south complex final. Aircraft Y responded; 'We are IMC.' I then stopped Aircraft Y at 7000' and instructed the pilot to track the localizer (basically sent the aircraft around but planned on keeping Aircraft X for the re-sequence in my airspace).  Later I reviewed the replay and observed that Aircraft Y had checked on prior to me actually asking for him and I didn't hear or respond to it. A few things should be changed and/or reviewed due to this and other situations that have recently become a problem at Los Angeles Arrivals (LAA) SCT. First off; due to staffing; we were trying to keep ZUMA combined at STADIUM as much as possible. When the traffic gets busy; ZUMA needs to be open and separate from STADIUM. Our staffing at LAA is terrible. I have had 2 Overtime (OT) shifts in the last 3 weeks and I am on the no OT list. I am not the only one going through this situation. 3-4 OT shifts per day is unacceptable when our workload is higher than usual with bad weather and airport construction and miles in trail procedures to the south complex runway. Which leads in to the second issue; our arrival rate is too high for our miles in trail restrictions. The overall rate for the hour might be ok (58); but sometimes the traffic is not evenly spaced throughout the hour. We will catch more than 15 airplanes in a 15 minute window even at a 58 rate; I looked at the TMU time line after I was relieved. We had caught 22 airplanes in a 15 minute window. This is unacceptable and causes the area to either hold aircraft; or overload the finals and stretch the downwind/base legs out. Both options increases workload and causes extra controller fatigue. This is doubled when you add it to the fatigue already accrued with the low staffing numbers and OT shifts. Lastly; Feeder Sector needs to be more observant and sensitive to Stadiums positioning during simultaneous and a 'fill the north final' flow (because of the south runway restrictions).


Second narrative: IFR day at LAX. Running simultaneous ILS approaches and we were unable to utilize visual separation from north side localizer to the south. Traffic was moderate to busy; at the same time I had Aircraft A that I noticed did not descend via the arrival as instructed. I was preoccupied with him trying to vector to find a spot on the arrival descent. I did not notice that Aircraft X was not in hand off status to the STAR sector. I subsequently transferred communication to the STAR without a hand off. STAR was busy as well vectoring people off the localizer. Aircraft X then lost staggered separation with the aircraft on the south complex. It was a busy having an assist would have made things easier.


Synopsis: SoCal TRACON Feeder and Final Controllers reported a handoff that was not made correctly which resulted in an aircraft having to be resequenced due to not seeing traffic.