Narrative:

Shortly after coasting in; approximately 1 hour and 20 minutes before estimated time of arrival; a message was received from flight control to increase speed if able due to advancing weather front that was potentially going to arrive at sdf near our estimated time of arrival. We were already advancing our airspeed to the maximum allowable based upon altitude and conditions and informed flight control that we would be unable to increase much more than our current speed. Just prior to the handoff from indy center to lexington approach control; we asked ATC if we would be able to coordinate with lexington a parallel track heading that would allow us to parallel the incoming front and proceed northeasterly so as to comply with flight controls request that we alter course towards cincinnati and then look for a way to penetrate the weather from the northeast side; working our way north and west and approaching louisville from the back side of the front.we coordinated appropriate vectors for that plan of action; however as we drew closer to the louisville terminal area; ATC opened runway 29 for arrivals and was vectoring traffic for rwy 29 RNAV approaches. ATC asked us if we wanted to do likewise and given our earlier coordination with flight control to work northeasterly as previously stated we originally said no. However; upon further study and looking at the weather approaching slower than expected to the terminal area we made the determination that one approach might be possible if we commenced it immediately. A clearance was received to prepare for the RNAV rwy 29 approach with vectors immediately to the initial approach fix. Listening to arrival traffic; we were particularly interested in the intensity of the weather arriving in louisville; and what if any potential existed for windshear or heavy rain. We received no windshear advisories during the initial approach segment; however once established on final and inbound descending to the minimum prof altitude; we did receive a confusing statement from louisville tower that quote: 'aircraft ahead reports 30 knot gain of airspeed on the ground'. We believed this to be in error and that what they were trying to inform us was a 30 knot increasing headwind on short final. The captain and I both reiterated the need to be aware of potential for windshear on this approach and even coordinated early with ATC that in the need of a missed approach; we would like to fly a heading of 220 and 5000 feet. ATC instructed us that in the event of a missed approach to actually fly heading 120 and maintain 5000 feet. Commencing the approach nearing 1200 feet AGL; we had visual contact with the airport and all associated lights. As we drew closer; we noticed via both weather radar and visually outside the cockpit a solid squall line which seem to be just west of the airport and according to ATC moving very slowly. The captain disconnected the autopilot in an effort to have better manual control of the aircraft during the final approach phase.we began to notice as we approached the 1000 ft. Mark that we might possibly be unable to establish ourselves within the stabilized approach criteria by then. Almost immediately and coincidentally with initiating the decision to execute a missed approach procedure; we received a windshear warning from the aircraft windshear automated system. The captain initiated the windshear avoidance procedure advancing thrust through the overboost bar and pitching the aircraft to the flight directed command pitch limit. Unfortunately we had already initiated a missed approach procedure; the captains initial command of go-around thrust/flaps 28 was being accomplished which was not appropriate for the later received windshear warning. We elected to leave the aircraft in a flaps 28/gear down configuration as to comply with windshear procedures at that point. Placing the aircraft in a climb headed towards 5000 feet and maneuvering the aircraft in a sharp left turn; to avoid the advancing whether; we encountered a severe windshear with increasing performance that advanced our indicated airspeed very quickly past 200 knots indicated and through 250 knots indicated. In addition; we were unable to reduce thrust because the windshear advisories in our FMA (flight mode annunciator) had not yet been extinguished; producing a level of energy; which also carried us through the 5000 feet clearance limit given by ATC. At approximately 6200 feet MSL and an actual heading of 080 (unsure exactly); the FMA annunciation extinguished; (possibly somewhat lower; but our energy state was too high to safely recover the aircraft until well after passing 6200 feet). We then attempted to bring the aircraft back to 5000 feet; established on airspeed of 220 knots as previously briefed during the initial approach. We were unable initially to comply with both the heading and altitude clearance issued by ATC and did not maintain configuration during the full windshear procedure as previously mentioned. During the abrupt maneuver to safely get the airplane away from the ground; and away from the advancing weather; ATC queried us on at least two occasions as to our altitude airspeed and intentions. Due to the maneuver we were delayed in communicating the handoff from tower to departure and making them aware of our deviations.establishing the aircraft on a 120 heading and 5000 feet the overboost bar had removed the auto throttles further complicating communicating our intentions to ATC. We recognized this and I ran the appropriate checklist to get the fadecs back to normal and reengaged the auto throttles. We then coordinated with both ATC and flight control for weather divert and a change of alternate airport to indianapolis. Further coordination with cincinnati approach control; indianapolis center; and indianapolis approach; allowed us to make a solid weather divert that was uneventful. After more than two hours on the ground coordinating with flight control; [operations]; and ground personnel; we then departed for the short flight back to louisville.

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Original NASA ASRS Text

Title: Air carrier flight crew reported encountering windshear conditions while on approach; executed the escape maneuver; and diverted.

Narrative: Shortly after coasting in; approximately 1 hour and 20 minutes before estimated time of arrival; a message was received from flight control to increase speed if able due to advancing weather front that was potentially going to arrive at SDF near our estimated time of arrival. We were already advancing our airspeed to the maximum allowable based upon altitude and conditions and informed flight control that we would be unable to increase much more than our current speed. Just prior to the handoff from Indy Center to Lexington Approach Control; we asked ATC if we would be able to coordinate with Lexington a parallel track heading that would allow us to parallel the incoming front and proceed northeasterly so as to comply with flight controls request that we alter course towards Cincinnati and then look for a way to penetrate the weather from the Northeast side; working our way north and west and approaching Louisville from the back side of the front.We coordinated appropriate vectors for that plan of action; however as we drew closer to the Louisville terminal area; ATC opened runway 29 for arrivals and was vectoring traffic for Rwy 29 RNAV approaches. ATC asked us if we wanted to do likewise and given our earlier coordination with flight control to work northeasterly as previously stated we originally said no. However; upon further study and looking at the weather approaching slower than expected to the terminal area we made the determination that one approach might be possible if we commenced it immediately. A clearance was received to prepare for the RNAV Rwy 29 approach with vectors immediately to the initial approach fix. Listening to arrival traffic; we were particularly interested in the intensity of the weather arriving in Louisville; and what if any potential existed for windshear or heavy rain. We received no windshear advisories during the initial approach segment; however once established on final and inbound descending to the minimum prof altitude; we did receive a confusing statement from Louisville tower that quote: 'aircraft ahead reports 30 knot gain of airspeed on the ground'. We believed this to be in error and that what they were trying to inform us was a 30 knot increasing headwind on short final. The Captain and I both reiterated the need to be aware of potential for windshear on this approach and even coordinated early with ATC that in the need of a missed approach; we would like to fly a heading of 220 and 5000 feet. ATC instructed us that in the event of a missed approach to actually fly heading 120 and maintain 5000 feet. Commencing the approach nearing 1200 feet AGL; we had visual contact with the airport and all associated lights. As we drew closer; we noticed via both weather radar and visually outside the cockpit a solid squall line which seem to be just west of the airport and according to ATC moving very slowly. The Captain disconnected the autopilot in an effort to have better manual control of the aircraft during the final approach phase.We began to notice as we approached the 1000 ft. mark that we might possibly be unable to establish ourselves within the stabilized approach criteria by then. Almost immediately and coincidentally with initiating the decision to execute a missed approach procedure; we received a windshear warning from the aircraft windshear automated system. The Captain initiated the windshear avoidance procedure advancing thrust through the overboost bar and pitching the aircraft to the flight directed command pitch limit. Unfortunately we had already initiated a missed approach procedure; the Captains initial command of Go-around thrust/Flaps 28 was being accomplished which was not appropriate for the later received windshear warning. We elected to leave the aircraft in a flaps 28/Gear down configuration as to comply with windshear procedures at that point. Placing the aircraft in a climb headed towards 5000 feet and maneuvering the aircraft in a sharp left turn; to avoid the advancing whether; we encountered a severe windshear with increasing performance that advanced our indicated airspeed very quickly past 200 knots indicated and through 250 knots indicated. In addition; we were unable to reduce thrust because the windshear advisories in our FMA (Flight Mode Annunciator) had not yet been extinguished; producing a level of energy; which also carried us through the 5000 feet clearance limit given by ATC. At approximately 6200 feet MSL and an actual heading of 080 (unsure exactly); the FMA annunciation extinguished; (possibly somewhat lower; but our energy state was too high to safely recover the aircraft until well after passing 6200 feet). We then attempted to bring the aircraft back to 5000 feet; established on airspeed of 220 knots as previously briefed during the initial approach. We were unable initially to comply with both the heading and altitude clearance issued by ATC and did not maintain configuration during the full windshear procedure as previously mentioned. During the abrupt maneuver to safely get the airplane away from the ground; and away from the advancing weather; ATC queried us on at least two occasions as to our altitude airspeed and intentions. Due to the maneuver we were delayed in communicating the handoff from tower to departure and making them aware of our deviations.Establishing the aircraft on a 120 heading and 5000 feet the overboost bar had removed the auto throttles further complicating communicating our intentions to ATC. We recognized this and I ran the appropriate checklist to get the FADECS back to normal and reengaged the auto throttles. We then coordinated with both ATC and flight control for weather divert and a change of alternate airport to Indianapolis. Further coordination with Cincinnati approach control; Indianapolis Center; and Indianapolis approach; allowed us to make a solid weather divert that was uneventful. After more than two hours on the ground coordinating with flight control; [Operations]; and ground personnel; we then departed for the short flight back to Louisville.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.