EMB ERJ 170/175 ER/LR
Flight Crew Air Transport Pilot (ATP)
Flight Crew Type 1300
Situational Awareness
Deviation - Speed All Types; Inflight Event / Encounter Weather / Turbulence; Inflight Event / Encounter Loss Of Aircraft Control
Air Traffic Control Issued New Clearance; Flight Crew Regained Aircraft Control
Weather; Human Factors
While at 10000 FT; 250KTS we were switched over to Approach. We were told to expect ILS 9 and descend to 3000 FT. We had been expecting [a different runway]. I was heads down trying to quickly reload the arrival and approach and get numbers for runway 9. I felt the airplane pitch nose down and looked up to see us greater than 10 degrees nose down; airspeed increasing; and descending rapidly in a right turn. I reached up pulled the speed brakes to full; took the controls and executed the nose low unusual attitude recovery. The highest airspeed I recall was 290 KTS somewhere around 8000 FT. I leveled the wings turning north of the arrival. We requested a heading. We were in and out of the clouds at night. We were aware of a small thunderstorm to the south of the arrival. I think we flew into a small thunderstorm that we were not showing on radar; and did not see coming. As a result I think we were in a downdraft that overwhelmed the autopilot. Approach and or Center could have told us what runway to expect further out. This would have allowed me; as pilot monitoring; to be heads up at the time of the incident.
Descending on arrival path; flew into a cloud that was not painted on radar. Upon entering cloud encountered severe downdraft and plane entered a descending left turn. Captain assumed controls of aircraft and continued turn out of cloud while I asked and was given a heading by ATC. We were below 10;000 FT and aircraft did speed up past 250 KIAS. Speed brakes were needed to slow aircraft back down. Incident lasted less [than] 45 seconds before resuming the arrival.
ERJ-175 flight crew reported recovering from an unusual attitude at 8;000 FT that resulted from a severe downdraft associated with convective activity.