A321 turbulence and stalling on autopilot

In the last few months, I’ve had two similar incidences in which I was flying an A321 out of KLAX on the DOTSS2 departure. At around the time I crossed DOTSS as I was approaching my planned cruising altitude of about FL350, I started gradually losing airspeed and the aircraft swayed uncontrollably from left to right, and then up and down. The autopilot throttle could not keep up with the turbulence and dropping airspeed, and eventually the aircraft stalled. The first time this happened, the aircraft was below MTOW but above MLW. Since I figured that the incident may have been due to the aircraft being somewhat overweight, I was sure the second time that I was below both MTOW and MLW before departing from KLAX, but alas, it happened again. I realize that this problem obviously has a lot to do with wind, but I’ve flown that departure countless times and have only ever had a problem with the A321. What can I do to prevent this from happening in the future with this and other aircraft?

Thanks so much,
Jack

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There is a known issue with the A321 bobbing a lot, but you can mitigate this.
Firstly, what is your cruise speed and weight? If you are too heavy, you may need to step climb to avoid stalling. As you said, if you’re above MLW, try a lower altitude first and see if it still happens.
Flying too fast can also result in an uncontrollable aircraft. Regular cruise speed should be M0.78.

A good solution is to deselect the ALT setting but keeping the VS at 0.

An A321 seldom climbs to FL350 initially especially on a transcon flight. At most do FL330 initially, speed at M0.77 minimum and you should be fine. Remember to reduce your VS as you gradually climb so that at least by FL290, you’re doing at most +1200fpm.

Hope this helps

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I second that. I usually adjust the Vs to maintain about 70% throttle during the complete climb. It helps avoid many issues.

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This is honestly why I hate the 321. It happens all the time and there’s really nothing you can do about it. One time I was doing like a 4 hour flight and came in to land that the tail just started swinging side to side and then the nose dipped and I stalled. Out of nowhere. I didn’t touch anything. It’s just so weird. I honestly don’t even fly the airplane anymore because of it.

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Check trim(around 40% should do), approach speed at 140-150KIAS, Flaps full everytime. It’s a tricky aircraft to fly. Perseverence is key here ;)

I just did a flight in the A321.

  • Just below MLW, 68% load
  • Climb 245 kias/VS 2500 up to 10 000
  • Climb 280 kias/VS 2000 up to FL280
  • Climb M 0.78/VS 1500 up to FL350

Moderate turbulence/winds

No issues, N1 did not exceed 85%

What VS did you use? And wind speed/direction at the time?

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