Date: 201603
Local time of day: 1201-1800
Location: SDF.Airport, KY
Flight conditions: IMC
Weather elements / visibility: Cloudy; 2
Light: Daylight
Aircraft: Widebody Transport
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Cargo / Freight / Delivery
Flight phase: Final Approach
Airspace: Class C SDF
ATC / advisory: Tower SDF
Second aircraft: Medium Large Transport; Low Wing; 2 Turbojet Eng
Reporter organization: Air Carrier
Reporter function: Pilot Flying; Captain
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Second reporter function: Pilot Not Flying; First Officer
Anomaly: Conflict Airborne Conflict; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter Unstabilized Approach; Inflight Event / Encounter Weather / Turbulence
Detector: Automation Aircraft Terrain Warning
When detected: In-flight
Result: Flight Crew Landed As Precaution; Flight Crew FLC complied w / Automation / Advisory
Contributing factors: Weather; Human Factors; Procedure
Primary problem: Human Factors

Narrative: During arrival into SDF; we requested deviation right of course to avoid an area of buildups. Upon contacting approach control; they advised us of a [wide body aircraft] Windshear (WS) of minus 20kts on final about 200 plus feet; and that GA aircraft reported a loss of minus 5 kts as well. At approximately 7 mile final; tower cleared Aircraft Y flight to take-off; 17R RNAV to LEENE; and cleared us to land. At about 1;000 feet agl; I reported the appch lights and runway in sight. I noticed a white light amidst a cloud of mist which must have been the Aircraft Y flight on take-off roll. I immediately thought that it was going to be close as I had thought that Aircraft Y was already airborne. Unfortunately it was not. At 500 foot call I thought to myself that we might need to go-around.... Followed by inputting a slightly less descent angle.I began to see the Aircraft Y acft rotate and become airborne. There was about 10 seconds between Aircraft Y liftoff and our wheels on the ground. I continued the approach as my mind was trying to calculate the possibilities of his takeoff RNAV TO LEENE; my go-around (intercepting IIU 264 outbound) and how our flight paths were very similar. There was a small amount of time where I decided that landing the aircraft would be safer than two aircraft occupying the same space at the same time. I elected that the safest option would be to land the plane. During this phase of flight I exceeded the minimum 1;000 foot VSI to approximately 1;200 feet at the most; flared and landed the aircraft without incident. At this time; I received a 'Sink rate; Sink Rate' call. Subsequent to my late decision that landing was more safe than a go-around; I estimate that I landed within 2;500 feet from threshold; and had at least 6;500 feet from runway remaining when Speedbrakes extended was called. We landed and taxied in without incident.I think that tower was more surprised than we were as they asked us if there was any WS on final. Our response was that we didn't know; because we were watching the Aircraft Y flight takeoff ahead of us....


Second narrative: [Report narrative contained no additional information]


Synopsis: An air carrier flight crew reported electing to continue approach and land despite close interval spacing of departing traffic on the same runway.