Date: 201705
Local time of day: 0601-1200
Location: SFO.Airport, CA
Flight conditions: IMC
Light: Daylight
Aircraft: B737 Next Generation Undifferentiated
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Final Approach
Airspace: Class B SFO
ATC / advisory: Tower SFO
Reporter organization: Air Carrier
Reporter function: Pilot Flying; Captain
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Workload; Distraction; Situational Awareness
Second reporter function: First Officer; Pilot Not Flying
Anomaly: ATC Issue All Types; Deviation - Speed All Types; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter Unstabilized Approach
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Became Reoriented; Flight Crew Executed Go Around / Missed Approach
Contributing factors: Human Factors; Procedure
Primary problem: Human Factors

Narrative: Due to traffic we were receiving many vectors and altitude/speed restrictions from ATC that were not published on the DYAMD3 arrival. Trying to comply with these restrictions distracted us and we failed to do the approach checklist. Consequently I failed to tune the ILS frequency that was in the standby window. We were vectored to intercept the approach approximately 3 miles outside of AXMUL on the ILS 28R approach. Our last assigned altitude at the time was 3000 feet. The intercept was accomplished in LNAV; and because we were high on the path; in order to avoid the aircraft from ducking down to the glide slope I instructed my FO to set 1800 feet in the window and planned to use level change to intercept the glide slope. Field conditions at the time were approximately 900 ft overcast so we were IMC. Because I had failed to tune the ILS frequency I mistakenly interpreted my display to be the glide slope instead of the path which still showed us to be a little high outside of AXMUL at 1800 ft. We were in a 30 degree flaps landing configuration by then. Because I had failed to tune the ILS selection of the APP mode did nothing and the aircraft leveled off at 1800. At that point it became obvious to both of us that something was not right and a go around was initiated. I however was not prepared for the amount of nose up trim the autopilot had put in; so when the autopilot disconnected the nose pitched up more than I was prepared for and we got an airspeed low warning. We recovered; continued the go around and the subsequent approach was conducted without further incident.


Second narrative: Inbound to SFO we received numerous vectors off course in addition to altitude restriction changes. While this is not outside the normal level of duties we see every day; it did somehow distract us from completing the Approach Checklist. We were getting high on the arrival and correctly set our arrival step down altitudes on the MCP using LVL CHNG to try and get down faster; but with continued speed reductions from ATC we were unable to get down and slowed soon enough. We continued to deviate higher from path for a proper glide slope intercept. At some stage near AXMUL (28R ILS GS Intercept) I thought I was helping the Captain get down faster by 'breaking the altitude' using the MCP altitude selector (I broke the altitude UP by selecting a higher altitude) but because we were still in LVL CHNG at the time what I inadvertently did was drive the flight director to climb. This is where we received the 'Airspeed Low' warning (no stick shaker) and the Captain disconnected the autopilot and executed a prompt recovery and missed Approach. We returned to SFO and landed 28L.


Synopsis: B737 flight crew reported executing a go-around after track and speed deviations resulted when they encountered distractions and high workload on approach to SFO.