A320 automatic nose-down just prior to touchdown

Hey everybody! I have a strange phenomenon that’s appeared in the A320 recently: The plane is pitching downward just prior to touchdown despite A/P off. I’ve been flying around the world using primarily this plane (tonight was flight 32 of 36, so I’m not completely unfamiliar with the aircraft!), and all of my landings have pretty much been exactly the same process.

Unless weather has prevented it, I typically fly with A/P on, APPR activated until I’ve been cleared to land and then I’ll disable the A/P entirely and hand-fly it the rest of the way. For whatever reason, the plane responds just fine from this point until it’s roughly 30-60ft above the ground. Early in my trip I would simply pull back a bit to flare, cut the throttle, and it would touch down without issue. Now, when I’d normally pull back to flare, the plane noses down as if it’s aiming for a specific AoA at touchdown, even though I have some back-pressure on the stick. Tonight I intentionally flew the plane down with a much steeper nose-up angle to see if it did it again, and it was like something took over and pushed the stick forward just prior to touchdown.

I’ve checked all assists and nothing is on that would be taking over for landing, my flight stick isn’t providing any random input that would do this, and I’m pretty much at a loss. I haven’t tried this in any other plane so I don’t know if it’s sim-wide or simply limited to this plane, but it’s extremely obvious. Is this a feature with the plane that I’m just noticing, or is this a new issue that’s appeared recently?

Thanks for your time!

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Correct behaviour. The airbus trims nose down intentionally during flare mode so you have to pull back progressively.

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Awesome, thank you!

I thought the real question is, “Why didn’t it happened before ?”

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Why does it do that? Is it trying to mimic the way GA behaves when landing?

Not only GA aircraft experience a nose down pitching moment upon entering ground effect. The same applies to large transport category aircraft. The downwash angle from the wing onto the stabilizer is getting smaller in ground effect, causing the nose to drop. According Airbus:

Flare mode

This mode is automatically engaged when the radar altimeter indicates 100 feet above ground and provides for a direct sidestick to elevator relationship. At 50 feet the aircraft trims the nose slightly down requiring the pilot to progressively move the sidestick rearward emulating a conventional control input for landing.

requiring the pilot to progressively move the sidestick rearward emulating a conventional control input for landing.

That’s pretty much what I meant when I said “mimic GA”. You progressively apply more back pressure until you touch down. I always found it interesting how the auto trim would still hold the nose where ever I put it when landing. I would essentially flare at 30-40ft to the 10ft callout and then leave the pitch at a slight 50fpm decent and the auto trim would hold it there until touchdown with the stick completely neutral on my part. I’m exited to try out the more realistic behaviour.

Thanks for the info!

It doesn‘t mimic GA though, it mimics any manual aircraft although I‘m not sure if that‘s t he reason behind it.

From my understanding, an actual Airbus pilot may correct me:

The cursed and wonderful Airbus FBW logic in normal law commands a roll/bank rate with left/right movement of the stick and (attention!) a g force with the forward/back movement. The sidestick fully back commands 2,5G which is also the g force of a turn at 67 deg bank angle.

At 100ft the Airbus enters flare mode which afaik includes alternate law. At 50 ft the pitch trim freezes, the fly by wire function isn‘t holding g force anymore, the stick/controls relation becomes much more direct, not 1:1 though and the current nose will be taken as a reference. At 30 feet the horizontal stabilizer starts to trim down to a -2 degrees pitch attitude over the time of 8 seconds. The pilot has to counter this behaviour. Best landing results are done with thrust manual and the stick being moved forward a tiny bit just a fraction of a second before the main gear touches the ground, at ground contact the spoilers will deploy and the nose will have a nose up tendency. Good that it‘s trimmed forward at that point, just release the stick a bit more until the autobrakes kick in. Always land with autobrakes armed for that reason, they bring the nose down immediately. With the wheels on the ground your FBW is in real direct law now.

I’m not sure, I believe flare mode is part of the normal law, although in essence its kind of alternate law indeed (it becomes a conventional aircraft without flight augmentation). The stabilizer trims slightly down, but not necessarily 2 degrees pitch I would think? You would obviously compensate for this effect, so what if it never reaches -2 degrees pitch down due to you giving progressively more nose-up input? Then upon landing you will be holding a slight back-pressure as the stabilizer is slightly causing a nose down pitching moment. So I assume you mean relaxing a bit of that back pressure rather than moving the stick forward. This might be a matter of definition, I guess you are meaning the same thing.

It takes the pitch attitude at 50ft RA as a reference, calculates the amount of trim required to theoretically reach a -2 degrees pitch attitude and then trims towards this THS setting within 8 seconds from reaching 30ft RA. Of course you will work against this with the stick but since the horizontal stab will trim down you have to add more and more upwards elevator. Possible that it’s still normal law but flare mode.

this. ^^

That makes sense!

A few flights after making my initial post and I can’t say I’ve really got a hang of this, it always feels like it has stolen the controls from me instead of making trim adjustments. Even when I try to apply extra pressure with the stick I can’t seem to overcome the nose-down adjustment. Tonight when I landed I had pulled the stick back to over half its maximum and the plane still nosed forward abruptly. Is there anywhere I can read up on this, or is there a video about it somewhere?

What sensitivity settings are you using?

Also make sure all flight assistant options are off.

Search on YT there are a number of videos!

No not at the right it’s doing it. It’s not just trimming down it’s literally trying to DIVE

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I only say this because it’s like it’s taking control away giving you no input whatsoever. It was right before where the nose would trim down automatically but you still had control and could counter it. After the recent update you can’t even counter it because for at least 2 seconds it’s like the sidestick is dead. That’s not supposed to happen

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I’ll have to check my sensitivity stuff later tonight when I get home, but I have every assist off. Beastking said exactly what I’m experiencing, it’s like something is taking over the controls and I have no influence over the plane at all. Even after it has nosed down the stick doesn’t seem to work anymore, it just stops working altogether.

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Yeah it’s not just trimming 2 degrees like it should like it would before the recent update. (It did do it but you had control and probably got used to landing the A320 that you never noticed it)

Oh wow okay, that‘s certainly not right.

I’ve been recording my landings for about 3 weeks to look back at how I could improve them, I know I have landings prior to this starting and landings where this happened. I can upload them later tonight and post them here. Obviously it won’t have my inputs but it’s plainly obvious that it has taken over from what I was trying to do and overrode my inputs.

I didn’t see it explicitly stated, but is this with the FBW A320?

If so, their support channel on Discord is really the right place to ask. They’ve helped me several times, from actual bugs to just gently letting me down when I’ve been dumb and not knowing what I’m doing.