B737 Undifferentiated or Other Model
Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 93; Flight Crew Total 3400; Flight Crew Type 3400
Troubleshooting
Deviation - Altitude Overshoot; Deviation - Speed All Types; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter Weather / Turbulence; Inflight Event / Encounter Loss Of Aircraft Control
Flight Crew Overrode Automation; Flight Crew Regained Aircraft Control; General Maintenance Action
Weather
Enroute from ZZZ to ZZZ1 at approximately ZZZZZ; we encountered chop at FL350 and decided to request FL390; which was granted. During the climb at approximately FL370 we encountered moderate turbulence. The airspeed increased into overspeed and the vertical speed increased significantly due to an updraft. Though I did not note the actual VS; I estimate at least 5;000 FPM based on the rate that the altitude tape was moving; which was where my focus was. I disconnected the autopilot; and as we went through FL380 I knew leveling at FL390 was going to be difficult because I couldn't safely decrease thrust any further; and pitching over would have made the overspeed worse. Using a little of each method; I was able to achieve a normal thrust setting and speed below max at approximately FL395 and returned to FL390; where we reported the event to ATC. We sent an overspeed code to Maintenance via ACARS. The sky conditions at the time were [VFR].
During climbout through FL370 we encountered an increase in both speed and climb while the B autopilot was engaged. After the PF (Pilot Flying) disengaged the autopilot the aircraft continued to increase in speed causing an over speed condition by approximately 10-15 kts. The aircraft continued to climb through our selected altitude; FL390; by approximately 400 ft. while the pilot flying was executing his recovery techniques to return the aircraft by to the correct altitude and speed. Approximately FL350 I had already asked the flight attendants to be seated because we had a small amount of turbulence. During the event; both the passengers and flight attendants were seated. I relayed the turbulence/updraft to air traffic control as severe in nature so that other aircraft wouldn't be routed through the area. After the event both the PF and myself felt that is was probably more of a moderate turbulence and more of a severe updraft. Shortly after; I checked on both the flight attendants and passengers to ensure no one was injured. The event was not jerky or real rough; it was more of a pretty smooth continual pitch up that was very difficult to stop without really over speeding the aircraft more than we did. I felt like the PF did as good of a good as possible in this strange situation.
B737 flight crew reported an encounter with turbulence and an updraft resulted in a temporary loss of control and overspeed condition.