Date: 201911
Local time of day: 0601-1200
Location: JFK.Airport, NY
Flight conditions: IMC
Weather elements / visibility: Turbulence
Aircraft: Commercial Fixed Wing
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Flight phase: Final Approach
Airspace: Class B N90
ATC / advisory: Tower JFK
Aircraft component: Electronic Flt Bag (EFB)
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: First Officer; Pilot Not Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine; Flight Crew Instrument
Human factors: Confusion; Training / Qualification; Distraction; Situational Awareness
Anomaly: ATC Issue All Types; Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy; 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
Contributing factors: Human Factors
Primary problem: Human Factors

Narrative: Approach at JFK. I was the NFP (Non Flying Pilot). Visual conditions with very strong gusty winds. ATIS reporting 320/24G33. We setup and briefed the approach and checked our EFB (Electronic Flight Bag) Flight Winds apps for crosswind component legality. The crosswind component on one of tower reports was 29 knots so I kept the app open on my EFB on final to be able to check it in the event the component went beyond the aircraft limitations. We were vectored inside AROKE(D11.0) then descended to 1500 ft. then immediately cleared for the 4L ILS just outside of KRSTL(D5.0) creating a somewhat shortened configuration time. Just after being cleared for the approach; the tower instructed us to slow and told us we were overtaking the traffic in front of us. We were in the process of configuring. The Captain had just called for flaps 25) and we were close to Ref (Reference) speed. This call from the tower was unusual and confusing as we couldn't see the traffic ahead and assumed it was airborne and close to us when in fact it was on the runway or at least past the threshold when I finally spotted it. I told the Captain that I thought the spacing looked fine. I was also checking the airspeed and noted we were close to Vref so there was no way to slow further. At that time the tower called the winds again; and the captain asked me to check the crosswind component. I didn't hear what they called for a wind speed and I was about to query the tower as I looked over at my wind app and noticed display compass rose was spinning in circles and flashing for some reason. I tried to reset it but at that point I realized it didn't matter as the tower then called the winds again and they were gusting to only 29 knots so I knew we were legal. The captain called 'stable' at 1000 ft. and we proceeded. I brought my attention back to closely monitoring the airspeed and sink rate as there was some variation of both due to the winds. I made the 500-ft call 'Stable-target-sink rate' and we proceeded. The distractions diverted my attention enough to where I did not return my attention to the checklist to ensure its completion and we were only configured to 25 flaps. At some point below 500 ft. and minimums we got an aural 'too low - flaps' and associated red warning light. I looked down and saw the flaps at 25 and I called for a go-around which the Captain initiated without hesitation. He did an excellent job and we cleaned up and were vectored around for another approach and landed this time on 4R. We landed uneventfully. In hindsight; I felt like the tower's call was neither necessary nor helpful and simply caused distractions on short final during what was a challenging approach in a strong gusty crosswind. There was a lot going on right about 1000' AGL. However; I should have not been distracted towards the wind app on my EFB which was malfunctioning and not really giving any beneficial data at that point in time. And; I should have made sure I looked down at the mechanical checklist prior to touchdown to ensure its completion. Going forward; I think my plan will be keep my hand on the last switch of the checklist until it has been completed. As a side note; I feel that the new triggers and flows relating to the landing checklist creates a break point at the 'down to the line' call; and the requirement for the Flying Pilot to make the call to complete the checklist takes away some attention.




Synopsis: First Officer reported failing to complete the Landing Checklist; which resulted to an improper flap configuration and consequently; a go-around.