Medium Large Transport; Low Wing; 2 Turbojet Eng
Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Flight Instructor; Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 35; Flight Crew Total 18300; Flight Crew Type 300
Time Pressure; Situational Awareness; Confusion; Distraction; Workload
ATC Issue All Types
Flight Crew Returned To Clearance
Human Factors; Procedure
One hour from destination we received the SFO Digital ATIS which indicated simultaneous charted visual approaches to runway 28 L & R in use.  We briefed for the most likely approach; which involved flying a VOR radial; with DME altitude requirements to a visual point and then flying visually to the runway with possible closely spaced traffic.  This is an unusual approach to set up and fly in our highly automated RNP cockpit; as it must be flown manually without the FMS; at night.  At about this time we started receiving multiple airspeed changes and delaying vectors from OAK center.  I would say we were vectored and returned direct to a way point no less than 15 times over the next 25 minutes.  As we were descending through the low 20's; we received the new ATIS which now stated that the LDA DME 28R PRM and the ILS 28L PRM approaches were in use.  Setting up and briefing for this new approach required considerable cockpit work; as well as reviewing the plate and the PRM requirement sheet which took easily 5 minutes to read and understand.  During this time the vectors for spacing continued.  Out of 5;000 feet; a frequency change to a new controller brought the news that the ATIS had changed again; and to expect the ILS 28R; and advise when we had info 'N'.  Digital ATIS was requested; and the advertised approach was the 'dependent' ILS 28 R & L.  A normal ILS and landing followed; however the workload during this arrival and approach was unacceptable in my opinion.  3 approach set ups and briefings during a high workload arrival resulted in what I consider to be an unsafe situation.  We are trained and equipped to fly RNP; LPV and RNAV SID's and STAR's; however our experience is we are very seldom left on any of these new arrivals or departures and are often vectored and issued altitude constraints which are different from those which are charted.  This provides the potential for confusion; loss of separation and ultimately defeats the purpose of these procedures.  This scenario is occurring more often in the NAS.
Pilot reports of numerous runway and approach changes inbound to destination airport.