Narrative:

While conducting the rdstn 5 into sdf we were given the following clearance: cross warsa at or below 14;000 MSL and descend maintain 12;000 MSL. The first officer inquired from ATC how the rides in the descent were; they informed us that light/moderate to 14;000 MSL and better below 14;000 MSL. We started our descent early to get below 14;000 MSL because our ride was becoming more moderate than light. Because of the ride and turbulence I had already slowed the aircraft to 270; seat belt sign was on; and the flight attendants were seated. As we descended through about 12;700 MSL the aircraft hit severe turbulence and we momentarily lost control of the aircraft. The following are estimates because the first officer and I both had a hard time reading the pfd because of the turbulence. The aircraft banked 30-45 degrees; airspeed trend vector was plus and minus 40 knots; and aircraft was pitched up above the horizon while descending. The autopilot never disconnected and we regained control around 12;200 MSL. I slowed further to 250 KIAS and requested lower to get out of the turbulence. The first officer; flight attendants; line check flight attendant all reported being ok and did not report any issues with the passengers. Landed; called maintenance; walked through the turbulence reports with the maintenance controller; and filled out the logbook.

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Original NASA ASRS Text

Title: EMB-175 Captain reported a momentary loss of aircraft control during an encounter with severe turbulence on descent into SDF.

Narrative: While conducting the RDSTN 5 into SDF we were given the following clearance: cross WARSA at or below 14;000 MSL and descend maintain 12;000 MSL. The FO inquired from ATC how the rides in the descent were; they informed us that light/moderate to 14;000 MSL and better below 14;000 MSL. We started our descent early to get below 14;000 MSL because our ride was becoming more moderate than light. Because of the ride and turbulence I had already slowed the aircraft to 270; seat belt sign was on; and the Flight Attendants were seated. As we descended through about 12;700 MSL the aircraft hit severe turbulence and we momentarily lost control of the aircraft. The following are estimates because the FO and I both had a hard time reading the PFD because of the turbulence. The aircraft banked 30-45 degrees; airspeed trend vector was plus and minus 40 knots; and aircraft was pitched up above the horizon while descending. The autopilot never disconnected and we regained control around 12;200 MSL. I slowed further to 250 KIAS and requested lower to get out of the turbulence. The FO; Flight attendants; Line Check Flight Attendant all reported being ok and did not report any issues with the passengers. Landed; called Maintenance; walked through the turbulence reports with the Maintenance controller; and filled out the logbook.

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.