Date: 201602
Local time of day: 1801-2400
Location: BWI.Airport, MD
Flight conditions: Mixed
Weather elements / visibility: 9
Light: Night
Aircraft: B737-700
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Flight phase: Initial Approach
Airspace: Class B BWI
ATC / advisory: Tower BWI
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Situational Awareness
Second reporter function: First Officer; Pilot Not Flying
Anomaly: Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter Weather / Turbulence
Detector: Person Flight Crew
When detected: Aircraft In Service At Gate
Result: General None Reported / Taken
Contributing factors: Human Factors; Weather
Primary problem: Human Factors

Narrative: While cleared to intercept Localizer course for ILS 10 (but not yet cleared for approach); BWI Tower turned [the] airport operation around to landing Runway 33 due to shift in winds. We were one of last aircraft to be sequenced to land on Runway 10. Now cleared for approach and on Tower frequency inside COLUM intersection; Tower reported winds of what I thought initially were 300/9G18. I realized an obvious tailwind component but was too focused on flying the approach at this point to process the component in my head. I asked the First Officer (FO) to quickly input new winds into [the performance computer] and adjusted VTARGET accordingly and had ample stopping margin on a long runway. Autobrakes were already selected. I asked the FO what the tailwind component was and he stated nine knots. We discussed the tailwind and we decided the FO would closely monitor the tailwind component on the FMC and we would go around if we saw the tailwind exceed 10 knots. An aircraft sequenced two planes in front of us then went around stating a tailwind component of 15 knots at approximately 300 feet. I asked the FO for reassurance that we had the new winds in [the performance computer] and confirmed our plan to monitor the wind information and be prepared for a go-around. The aircraft directly ahead of us landed uneventfully. The FO was making tailwind callouts all the way down the Final Approach Course and I could see the field around 900 feet AGL (better than expected weather). The tailwind never exceeded 10 knots and we landed normally. After parked at gate; I began processing the events again and was able to generally compute the tailwind component in my head and compare it to the known computed tailwind component from [the performance computer]. It then didn't make sense to me. I pulled out [the performance computer] and noticed that the FO had input the winds as only 300/9; and not 300/9G18 (the value I thought I had heard). When I input those numbers; it had a tailwind component of 17 knots. The FO had already left the airplane. I called him and discussed the event and determined we should fill out a report. Looking back; I should have made time available to more fully explore the changing airport conditions by requesting to be taken off the approach. I would have then been able to fully devote my own attention to the obvious tailwind. This was the last leg of a two-day trip. My FO was very experienced; very proficient and needed very little if any direction. I felt very comfortable not verifying his [performance computer] inputs. In this situation; I should have been more directive in stating the winds to input. I also should have recognized I was task saturation and couldn't compute that information in my head; which I was able to do fairly easily when at the gate. If I would have given myself more time (like going around) I'm confident I would have recognized that an input error had been made. Even just 2-3 more minutes of 'think' time would been enough to correct the mistake. I also most likely task-saturated my FO in a high workload environment which led to his input error or his communication error (not hearing the reported winds). Again; the safer thing to do was to break off the approach and give both of us more time to understand the rapidly changing conditions. Had I had the correct information; I would have [gone] around and sequenced for Runway 33. Other contributing factors: The length of Runway 10 gave me confidence in continuing. Had it been a short runway with obvious stopping margin issues; I would have gone around. The FO was a commuter with a fairly short connect time to make his flight home. Though this was not an obvious factor in my head to rush; we had many discussions throughout the day regarding this fact which may have unknowingly influenced both of our thought processes. In the future I will address the commuter issue early in the day to set the expectation that we won't let thoughts that canlead to rushing interfere with doing the right thing.


Second narrative: Both the Captain (PF) and I closely monitored the tailwind component via the Progress page 2 ensuring we didn't touch down with a value greater than 10 knots. The tailwind component on our landing was exactly 10 knots. Upon shutdown; the Captain; via the [performance computer]; recomputed the tailwind component based on what Tower called the winds. It showed us landing with an excessive tailwind component.With the winds shifting at the field and one aircraft going around; we should have taken the more conservative route and discontinued the approach. IRS derived winds had us legal. However; with Tower reported winds; we should have gone around.


Synopsis: B737-700 flight crew reported landing with a reported tailwind component exceeding 10 knots.