Air carrier pilots reported during cruise flight they entered a weather build up and lost airspeed and altitude. Pilots exited weather and regained aircraft control.
Synopsis
Air carrier pilots reported during cruise flight they entered a weather build up and lost airspeed and altitude. Pilots exited weather and regained aircraft control.
Narrative
We were enroute at FL210 with notable weather build-ups in the area; we were instructed to hold at ZZZZZ as published. Upon nearing the ZZZZZ waypoint; I noticed a significant cloud build-up ahead and turned on the weather radar for a more accurate assessment. The radar confirmed the presence of a build up directly ahead. I advised the Captain of the weather conditions and the potential turbulence and even offered to call ATC for new instructions. Despite my concerns and three subsequent alerts; even though I expressed that I was not comfortable with the situation and that we'd end up holding inside of the cloud; the Captain decided to proceed with the holding pattern at ZZZZZ. The Captain assured me that the clouds were beyond the waypoint; contrary to my radar readings. As we approached the waypoint it became clear that the build up was not beyond ZZZZZ.We were instructed by ATC to hold at ZZZZZ at FL210 and were maintaining a speed of 188 knots; according to the QRH for the given weight and altitude. As we entered the hold; the build-up was directly over the waypoint. I cautioned the Captain about our speed and the potential for turbulence as we entered the cloud. The Captain decided to maintain speed of 188kts.Moderate turbulence was encountered immediately upon entering the hold. The autopilot disengaged; and the stick shaker activated twice as we were turning. During the turbulence; we experienced a loss of 500 feet in altitude and bank angle"; though the exact speed reached during the encounter is not recalled.I informed ATC that we were unable to continue holding due to the turbulence. ATC instructed us to fly heading 360.The Captain successfully brought the wings level and regained control; stabilizing the aircraft back to the previously assigned altitude. After exiting the turbulent area; the remainder of the flight proceeded without further incidents.Cause: Lack of situational awareness of where the cell was actually located and the risk associated with Thunder storms.Suggestions: Emphasize the importance of utilizing weather radar and respecting weather advisories from all crew members. Encourage adherence to standard operating procedures (SOP) regarding severe weather avoidance."
Second reporter narrative
As I entered a hold over ZZZZZ at FL210 I encountered a buildup causing us to receive the stick shaker twice and bank angle. We were given a hold as published at ZZZZZ with no indication of weather at the fix from ATC. we slowed down to holding speed per the charts as soon as possible to avoid many laps in the hold. At that time my FO brought up concern about weather beyond ZZZZZ. We had the radar on and were watching the weather. There was a buildup beyond ZZZZZ that appeared to be far enough away. We had an aircraft enter the hold ahead of us 25ish NM and 1000 feet above us. He asked for accommodation around weather. ATC asked if they were still able to hold over ZZZZZ they replied with yes as long as we can get around this weather. ATC never asked if we wanted to change course. I looked at the weather radar and noticed that ZZZZZ was covered in green radar. The FO brought up concerns again and I thought that we would make the turn outbound before hitting the buildup. I was wrong as we hit ZZZZZ we entered the buildup and encountered an updraft causing us to get the stick shaker I disengaged the auto pilot and lowered the nose of the aircraft and recovered loosing minimal altitude. We started our turn in the hold and reported moderate turbulence and we can't continue in the hold. As we were in the cloud we received ice speeds and received the stick shaker again I again lowered the nose and recovered. Loosing around 500 feet in altitude all together. ATC gave us a turn to 360 I increased the bank beyond 40deg and received bank angle then recovered. We exited the buildup and I recovered the aircraft to FL210 (Heading) HDG360. I called the Flight Attendants and asked if everyone was okay and received the answer that everyone was sitting down and was ok. The buildup was growing faster and moving quicker than anticipated. Cause: Long/late day and didn't anticipate the weather to change so quickly Suggestions: Utilize CRM more and avoid the weather
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.