A320neo autopilot ascend and descend issues

Hi everyone, need help. I found myself in situation that the autopilot behave as not intended (maybe). 1) I am nearly not able to get to cruise altitude. Aircraft mearly gets to FL220 or so and it it very hard and slow to get any higher. Using managed altitude mode is not increasing altitude at all even if I see that the target altitude is planned (and set) to be FL380. Navpoints limitation is not the case as in the flight plan I should already be in FL 380. When I switch to VS mode it begins climb but waaaay to slow and I am constantly loosing speed (autothrotle is on). It takes forever to gain even 1000ft. About at FL330 it begins to get wavy. Few feets up and some down, and again and again. Why is that? Am I doing something wrong? Or it is normal behavior? 2) when I get to descend phase autopilot gets me down very fast, not considering waypoints altitude, ignoring “start descend” arrows on flight plan, just imidiate “fall from the sky”. How to do it the correct way? To end at the desired altitude at given waypoint? Can autopilot do this for me, or do I have to tell it how to do it? So far it just drops down at highest rate possible.
Many thanx for any help or guidence

Where do you place your throttle position? Is it at the CL detent? Is A/T on?

Yes, it is on CL and A/T is on… That’s why I am so confused with it’s behavior :frowning:

If you are heavy and/or the temperature is high, the climb performance is pretty weak IRL as well.
The MSFS A320 unfortunately additionally noticeable underperforms.

That said, make sure that you are climbing at Mach, not IAS above ~FL280 at ~M0.72.

How to use Mach instead of IAS? Sorry for newbie question, where to find it and what is the difference?
And I am usualy trying to climb about 500ft/min and still it looses speed pretty fast, is 500 Ft/min too much at these altitudes? Anything more than 500 is smelling like stall happening shortly as speed falls rapidly down

Usually the speed mode changes automatically to Mach after a certain altitude. Or you can just press the SPD MACH button next to the airspeed knob. I usually just let it do manage climb until my cruising altitude, and not really need to think about going to V/S mode myself. I just let it do its thing.

As long as I set the INIT page properly and the PERF page properly as well, it usually climbs okay and reached my cruising altitude of FL380/390 about 15-20 minutes after takeoff.

I’m not sure, but AFAIK you are flying the FBW A320, not the default one with its anemic climb performance.

U am using the default one as there is not any other option on Xbox… And it feels exactly as there is not sufficient power to climb to these altitudes. Engine thrust managed, levers set to CL, A/T is on, and the engines indicate that they are running at 84,4% thrust.
What exactly to check on init and perf page to be sure that there is not an issue with this setup?

I keep forgetting to look for the Xbox tags… :man_facepalming:

Don’t worry, I’m on a PC but I’m using the default A320 as well.
There’s a bug which prevents N1 from increasing during climb.
You could manually firewall the thrust levers for climb, but the performance improvement is rather insignificant. ~ 100ft/min

The init and perf page don’t affect the climb performance.

Keep in mind that climbing as high as possible isn’t necessarily the target and not always desireable.
The fastest flight level is ~FL280, but that’s rather uneconomical.
FL330-350 are more typical FLs.

Climb is only possible with excess power above your speed maintenance requirements. Is possible to make it to FL390 at 60tons gross weight but the usual climb profile is as follows.

IAS V2+15 at FLX to thrust reduction altitude.

Green dot at CLB until flaps retracted.

Then 250kts or SID speed restriction.

Then 270kts above 10,000ft until reach 0.72 mach.

Then to cruise altitude at 0.72 mach.

Usually cruise at 0.77 with tailwind, 0.78 still air or 0.79 with headwind.

If there are strong tailwinds in the jet stream and you want to get there quick can climb at green dot to 10,000ft and then 250kt to 0.72 mach.

Or if strong headwinds all the way then 300kts once above 10,000ft to 0.72mach.

Green dot is the best lift to drag speed and changes automatically with weight loss as fuel burns off. If you are climbing through an icing layer and want to get above ASAP climb at green dot speed.

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These are Indicated speeds - wind has nothing to do with those.

Many thnx for replies and guidance. As of now i will not bother with cruise altitude as high as possible and will set up some lower values at fligh plan. Only thing remains. I have to time after time request ATC to assign a lower FL as it realy loves to send me way to high. “Expedite your climb” annoyes me terribly :wink:

They are indicated speeds but airlines tend to slow down to make the most of tailwinds and speed up in headwinds to reduce the penalty.
If the FMC was working properly, inputting the cost index would work it all out.

That’s new to me. I can’t think of a single flight where we deviated from the optimum climb speed due to a head or tailwind component.

Furthermore climbing at green dot speed through an icing layer is a bad idea.
At green dot speed you are already very close to your minimum speed and if ice accretion starts to reduce the aerodynamic performance of your aircraft you are in a really bad situation.

Regarding cost index… How does it work here? The lower number the better? In relation to speed and thrust needed…

Your lucky!
My a320 neo, doesn’t even show up on the runway :joy::joy:

Try using selected altitude instead of managed altitude mode.

I know I don’t do what most do, but this is what I do on Xbox with the vanilla 320:


• Arm altitude with the initial altitude given by ATC clearance and engage selected altitude mode.

• Engage FD

That’s it.


• Takeoff

• Throttle back to the CLB detent

• Engage autopilot (auto thrust should be on already too)

• Do nothing except for altitude dial changes.

I never touch my speed dial until I am on approach. Heading I don’t touch whatsoever for the entire flight. Vertical speed i never use either. Just selected altitude and the plane does the rest, with only speed changes needed for final.

Hey, it may not be proper according to proper pilot method, but this is extremely simple and the plane just flies itself when doing it this way so it’s what I do.

Again, never touch the speed dial until on descent nearing decel for approach and final. Never touch heading or VS at all unless needed for a missed approach, emergency, or something to that effect. And use selected altitude mode not managed altitude mode (press X when you enter altitude, not A. There should be no little dot beside the altitude number on the deck display if doing it this way).

I don’t know why, but this seems to be the way for flawless performance on Xbox.

Nice good night book :slight_smile:
Thanx a lot, I am getting into it