Date: 201207
Local time of day: 1201-1800
Location: ZLA.ARTCC, CA
Aircraft: EMB ERJ 135 ER/LR
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Cruise
Airspace: Class A ZLA
ATC / advisory: Center ZLA
Second aircraft: B737 Undifferentiated or Other Model
Reporter organization: Government
Reporter function: Enroute
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Communication Breakdown
Second reporter function: Enroute
Anomaly: ATC Issue All Types; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Air Traffic Control
When detected: In-flight
Result: General None Reported / Taken
Contributing factors: Human Factors; Procedure
Primary problem: Procedure

Narrative: A B737 was pointed out to us from Sector 27 prior to GMN climbing to FL400. The data block was temped climbing to FL340. There was no traffic at that time and the D-Side approved the point out. I don't remember who took RADAR on an E135 level at FL370. I cleared the E135 direct REYES which put him in conflict laterally with the B737. My D-Side was on the land line coordinating with Sector 30 at the time. The B737 was still temped at FL340 at this time and Sector 27 had already taken RADAR on two aircraft opposite direction traffic at FL350. When clearing the E135; I assumed that Sector 27 would leave the B737 level at FL340 due to the opposite direction traffic. Sector 27 decided to climb the B737 to jump the traffic without knowing about the E135 above the two aircraft at FL350. When our team observed the B737 climbing to FL400; my D-Side called Sector 27 to attempt to stop the B737 at FL360. I turned the E135 to a 185 heading to diverge from the traffic. To contribute to this event; I turned the E135 into a lateral conflict with the B737 without ensuring that I or my D-Side had called Sector 27 to show them the E135 as traffic. Outside contributing factors: At the time of the event my D-Side was involved in coordination regarding a situation that had developed in a different part of our sector with two aircraft at FL330 being handed off the same sector. Sector 26 and Sector 27 share a shelf that is highly contested and complex. Sector 27 has FL240-FL280. Sector 26 has FL290 and above. All of the aircraft climbing out of the LA basin and landing Oakland are routed through this area. Sector 27 decides whether or not to climb these aircraft into Sector 26's stratum and makes point outs accordingly. This area is also a high traffic area for Sector 26's traffic landing in the LA basin from the north. Complex situations arise when point outs are made early and new traffic arrives [and] as both sectors work to climb aircraft to altitude and descend aircraft for a landing. The shelf FL240-FL280 was designed to allow Sector 27 to keep their aircraft in their airspace but most aircraft file much higher altitudes. If there was a more concrete Field Standard Operating Procedure (FSOP) regarding aircraft heading to OAK from the basin area then there would be fewer situations where new traffic must be constantly called for point outs made 10 minutes ago. If Sector 27 had an altitude to keep aircraft below regardless of requested altitude or if the aircraft were required to be level when entering Sector 26's airspace; this would reduce complexity and coordination.


Second narrative: Sector 27 gave point out to Sector 26 the B737 prior to Gorman no traffic at that time. While conducting coordination came back on frequency realized R-Side gave the E135 direct REYES at FL370 with point out the B737 FL350 climbing FL400 direct PXN realized it was not going to work tried to call Sector 27 to stop the B737 at FL360. As D-Side; I accepted the point out with no traffic at that time. Due to an early point out from Sector 27; and addition coordination with Sector 30 sequencing aircraft to SAN. [There was] lack of communication between R and D sides due to complexity. Aircraft departing LAX basin area landing Oakland should not be climbing in Sector 26 shelf. If aircraft were level this would not have happened. This has been an on-going problem regarding aircraft landing Oakland; climbing above FL340 departing the LAX basin area. Sector 27 was given airspace FL240 to FL280 to resolve this problem. This airspace is rarely used for this purpose.


Synopsis: ZLA Controller described a loss of separation event noting the failure of internal coordination and less than clear shared airspace responsibilities as contributing to the occurrence.