Helicopter
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 60; Flight Crew Total 9000; Flight Crew Type 200
Distraction; Confusion; Communication Breakdown; Situational Awareness
ATC Issue All Types; Airspace Violation All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Provided Assistance; Flight Crew Returned To Clearance
Airspace Structure; Human Factors; Procedure
Approximately 25 East of SFO I contacted NORCAL Approach on [frequency] and requested VFR flight following to SFO. I was level cruise at 3300 feet MSL. I was given a VFR transponder code and proceeded to SFO. I began a gradual descent and proceeded through Oakland Class C airspace. I was not directed to contact Oakland Tower. I continued to descend to 1000 ft. over the Bay. I was getting very close to SFO and requested NORCAL for a frequency change to SFO Tower. I immediately contacted SFO on [frequency] with my position and intent. The response from the SFO Tower was 'Who is this and you can't just fly in here'. I responded with my Call sign and that I had been flight following with NORCAL Approach. I was then asked when I had been up with NORCAL and what frequency. I responded that I had been with NORCAL until I called him and on [frequency]. The SFO tower response was basically 'Oh'; then he cleared me to the ramp at SFO. I remember thinking it was odd that I had not heard the words 'You are cleared into the Bravo Airspace at or below an altitude'. But I just thought NORCAL was busy and I had been momentarily forgotten. I was also approaching SFO from a different direction (East instead of North) than I have in the past. My mistake was not verifying by Bravo clearance much earlier.
Pilot receiving flight following is transferred to SFO Tower by pilots' request. Controller doesn't know who the aircraft is and chastises pilot. Pilot advises Tower that they were under flight following by TRACON; and Tower Controller lets aircraft land at destination without any problems.