Regional Jet 900 (CRJ900)
Air Traffic Control Fully Certified
Communication Breakdown; Confusion; Training / Qualification
ATC Issue All Types; Deviation - Altitude Crossing Restriction Not Met; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter CFTT / CFIT
Air Traffic Control Provided Assistance
Procedure
Aircraft X was on the new METROPLEX RNAV approach inbound to LGB. The pilot was given the phraseology to descend via except maintain 5000. The pilot read back everything correctly but was confused by what that meant with the new procedures. The pilot immediately started to descend to 5000 instead of complying with the crossing restrictions of the arrival. Since it's a new procedure; I asked the pilot if he was descending with arrival which the pilot responded yes. When I pulled up the map he was way below the arrival and also below the MVA.It's early in the Metroplex implementation but some of the pilots still seem confused on what they are supposed to be doing with the procedure changes.
SCT TRACON Controller reported confusion from an inbound LGB pilot on a the new Metroplex RNAV Approach clearance.