Ok I was departing taoyan international airport today and at 1700ft on the a350 the plane starts going left and right on its own I had vs set on the auto pilot and heading also set but the plane keeps going left and right could this be turbulence or what is the cause I had this same issue departing Sydney airport also
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The reason this is happening is because your speed is too low. Assuming you were flying a relatively full flight, 170 knots is way too slow at 2000 feet after takeoff. This, probably combined with a little crosswind, causes you to rock side-to-side.
Generally speaking, you should at least be past 200 knots and accelerating by that altitude. Just be sure not to exceed 250 knots until you pass 10,000 feet.
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It happens to me too, it’s either your going to slow or you need to decrease the rate of your V/S
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Yeah, the plane waving from the left and right usually happens when the speed is too low. It also happens when I try to surpass the service ceiling in aircraft, usually above 43Kft. When the plane starts waving, I usually take it as a sign to reduce my altitude.
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He’s at 1,700 fpm, which is pretty reasonable for an A350 at any weight.
I was flying at 97% load rotated at 156 when I climbed to 3000fpm I stalled for just no reason
And then I did it again this time went to 2500fpm after getting to 1000agl and bright the nose down to 1700fpm and then the plane starts going left and right I had to increase the throttle to 100% then at a certain speed the plane became stable
I confirm, your speed is too low. At 2000ft, you should reach about 210-220kt.
Going for a VS rate is not as important as going for the speed which the aircraft needs to fly. When you have the speed, you can think about VS rate. No speed, no rate, just stall! 
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Well I used 97% n1 for take of because I was on over 90% load I rotated at 156knots and climbed to about 15 degree then the speed stop going up I had to bring the nose down and maintain 170knots till I get to 5000 ft before the plane starts going left and right
It didn’t stall for no reason. 97pct load with 300fpm is way too much to ask, especially in an A359 just after takeoff.
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What weight did you input for that? No good aircraft performance database will tell you to immediately take a 97% full A350 up to FL430 immediately with no step climb.
This is just a normal a350 profile without inputting any weight or anything ! I use simbrief for my flight planning and the toc was fl340 then when climbing I use this a350 aircraft performance data according to the way I climb
It’s probably assuming your operating nearly empty, hence the insane outputs it’s giving. When operating with passengers and cargo, especially at 97% of the MTOW, it simply won’t be able to make it to FL430 or climb out at 3000 fpm. Try adjusting for your weight next time.
Initial climb to 5000 is what speed on the a350?
I have experienced similar issues before. I was just about to descend and the A350 just sways left and right for about 2 minutes. Then it flies normally. There was no wind and my load was about 35%. Maybe it’s an Autopilot bug?
Yes then probably something is wrong with the a350 and infinite flight has to look into this
Depends what weight you’re operating at.
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These kinds of errors are almost never an autopilot bug but rather user error. If you don’t mind telling me, what cruise speed were you add before starting to descend?
97% load corresponds to approximately 275t (275,000kg).
The S speed, or the minimum speed you should be retracting from flaps 1 to 0/flying clean, at this weight, would be 206kts.
The green dot speed, or optimum lift/drag ratio speed, at this weight, would be 232kts. While not a “safety speed” that has to be adhered to like the above S speed, according to Airbus procedure, it is also known as the “final takeoff speed” (short of the 250kts below 10000ft restriction), and you can, but not necessarily must, aim for at least this as soon as practicable in order to give the best possible climb performance.
In your case, at Taoyuan Airport, this can be done after clearing the initial 210kt speed restrictions present on most (if not all) SIDs.
Point being, 170kts is too slow as a “steady” climb speed to be maintained after acceleration altitude at this weight, with no flaps or slats out as indicated in your screenshot.
Yep. Don’t be afraid to reduce your V/S even further to attain the minimum clean speed and climb speed quicker - especially when climb gradient requirements at RCTP are not very demanding comparatively speaking.
Ideally you should pitch for whatever V/S maintains a speed target with the given thrust setting - meaning that you should not expect the V/S to be “constant”; and that climb rates of 3000fpm (or more) can be attainable even close to, or at MTOW depending on conditions, especially after takeoff. Of course there are many variables at play here, and what may be true in some circumstances may not be in others, hence why such a sweeping generalization isn’t really beneficial at all.
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