Small Transport; Low Wing; 2 Turbojet Eng
Flight Crew Instrument; Flight Crew Flight Instructor; Flight Crew Flight Engineer; Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine
Flight Crew Last 90 Days 35; Flight Crew Total 19000; Flight Crew Type 520
Workload; Communication Breakdown; Situational Awareness; Confusion
ATC Issue All Types; Deviation - Altitude Undershoot; Deviation - Altitude Excursion From Assigned Altitude; Deviation / Discrepancy - Procedural Clearance
Air Traffic Control Issued Advisory / Alert; Flight Crew Became Reoriented
Procedure; Airport
We were flying a Part 91 corporate trip to EMT. We had begun our descent and were leveling at 7000. Last assigned routing was LHS Direct DARTS. We requested the GPS B approach into EMT. We were switched to a new SoCal approach frequency. He gave us a new routing that we had not filed or expected. We had the airport in sight; so instead of accepting the clearance. We selected to cancel IFR and proceed VFR with flight following. The controller acknowledged our cancellation and said 'proceed with pilot discretion'. At this point we both thought he said 'descend pilot discretion'. So we descended for our visual approach in to EMT. We also turned direct to the airport. We passed north of DARTS intersection by about 2 miles. About 1 minute into the descent the controller asked what our altitude was. We said 5;500 descending to 3;500. His tone was not approving and we became confused about the status of clearance. The controller stated that our attempts to make a clarification were garbled. We attempted again; with the same results. In our third attempt; we squawked 1200 and said we said were cancelling and proceeding VFR.It was unclear to us if he had accepted our cancellation of the IFR clearance. Or that he understood we would; in the near future (i.e. arrival at DARTS intersection) be cancelling.In hind sight; we would have been clearer if; on initial contact we had expressed our desire to cancel and proceed VFR. I think the intermediary step of 'VFR with flight following' confused everyone.
[Report Narrative Contained No Additional Information.]
A corporate jet flight crew on approach to EMT were confused by a SCT Controller's disapproval of their descent for the airport after they cancelled IFR and began a visual approach at night.