Date: 201604
Local time of day: 0001-0600
Location: EWR.Airport, NJ
Flight conditions: VMC
Weather elements / visibility: Rain; Turbulence
Aircraft: B737 Undifferentiated or Other Model
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Final Approach
Airspace: Class B EWR
ATC / advisory: Tower EWR
Reporter organization: Air Carrier
Reporter function: First Officer; Pilot Not Flying
Human factors: Fatigue; Workload
Second reporter function: Captain; Pilot Flying
Anomaly: Inflight Event / Encounter Unstabilized Approach; Inflight Event / Encounter Weather / Turbulence
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Executed Go Around / Missed Approach; Flight Crew Diverted
Contributing factors: Weather; Human Factors
Primary problem: Weather

Narrative: We were aware of forecasts for extreme winds in EWR at the time of our arrival; and had coordinated with dispatch for an alternate with forecast winds that we felt gave us the strongest diversion option if landing at EWR was not possible. On arrival into EWR; the wind was gusting at over 40 knots and favoring the shorter runway 29. We used the RNAV approach; which got quite rough below 2;000 feet. Additionally; the window between our gust protection speed and our max flap speed was very narrow. Within about the final 800 feet of descent; maintaining runway alignment became increasingly difficult; and maintaining speed within tolerance proved impossible; at which point we executed a go-around. Given the difficulty of the previous approach at such a low altitude; and our having flown all night; we felt that attempting another approach was not the safest option; and opted to divert to ZZZ. Someway into the diversion; dispatch contacted us to request we change our diversion airport to ZZZ1. The combination of the go-around and the two diversions; followed by another fairly high-wind gust approach to landing into ZZZ1 was quite labor-intensive; and through the process; we found ourselves making a number of small mistakes with automation management; CRM; etc. When we landed; we were advised that the company was planning on having us refuel and operate the aircraft on to EWR. Upon weighing the conditions in EWR against our own physical state; and the mental fatigue of the preceding hour of flight; we felt that it was not possible for us to provide an acceptable margin of safety for the continuing flight to EWR; at which point we advised the company of our need to remove ourselves from that flight segment.


Second narrative: Flew RNAV approach to RWY 29 in high wind; low visibility; and moderate turbulence. I fought the entire way down with ref speed close to flap speed; flaps blowing up several times; and moderate turbulence. At approximately 100 feet while the aircraft was in the correct position I was unable to stabilize the airspeed enough to continue to touchdown and so went around. The go around was not the result of not being configured; or being in a bad position. I reasoned that a second approach would end with the same wind conditions so elected to divert. During the go around and divert the First Officer and I fought to keep the aircraft in the correct modes; with turbulence causing the autopilot to revert to Control Wheel Steering (CWS) mode several times. We first completed all necessary items to divert to ZZZ; our flight plan choice. Then on advice of Dispatch we did it all again to divert to ZZZ1. During this we made several errors due to stress/fatigue including typing in an incorrect fix and initially turning in the wrong direction catching it before the turn was complete. While the weather was better the landing also included 40 plus knot winds. After completing our assigned flight to a miss; and a second intense flight we felt mentally and physically exhausted and did not feel that we were capable of safely operating a third leg.


Synopsis: B737 flight crew reporting diverting to an alternate after executing a go-around at EWR due to high winds; turbulence; and an unstable approach.