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A320Neo Rotation Law

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A320Neo Rotation Law

Old 2nd May 2023, 10:54
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A320Neo Rotation Law

Hi all, I had heard that the 320neo had a new rotation law... I tried it in the sim, and yeahh it does feel very abnormal TBH.
By abnormal, I mean, the aircraft just felt very disconnected and hesitant to rotate, well past rotation speed.

Is this accurate to real life?

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Old 2nd May 2023, 16:45
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When was the sim last calibrated? Most sims are reasonably good but some are way off.

For example the pause at 10 degrees on rotation is not realistic at all in most 320 sims.
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Old 2nd May 2023, 16:48
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Originally Posted by Boeingdriver999
When was the sim last calibrated? Most sims are reasonably good but some are way off.

For example the pause at 10 degrees on rotation is not realistic at all in most 320 sims.
Hmm, not too sure
It kinda reminded me of the 737-800 actually, which does have a noticeable pause, due to the ground effect from the Horizontal Stabilizer.
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Old 2nd May 2023, 22:17
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Your SIM description sounds austere. If anything, the NEOs compared to the classics tend to jerk up the pitch just after lift-off.

Once you learn to contain that by reducing the SS deflection early, come back to the older models and you'll get the 737 pauses nice and pronounced - pilot induced.
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Old 3rd May 2023, 01:55
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So remember to learn how to pass the simulated check.

Not how to operate the real aircraft.

Two distinct things
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Old 3rd May 2023, 02:43
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I was told by someone who does it for a living that the laws on the new Airbus aircraft might do different things on paper, but the different things are designed to make the NEO Airbus aircraft (which have slightly different raw aerodynamics) handle as close to the old one as possible.
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Old 3rd May 2023, 03:25
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The NEO has Rotation Mode (27-20-10-20) which means that the sidestick commands a pitch RATE demand so the aircraft doesn't hang at 10 degrees (when the tail gets stuck in ground effect).

The CEO doesn't have this mode and it blends from ground mode (sidestick directly commands the elevator) to flight mode (sidestick commands 1g).

For those mentioning it 'jerking up at 10 deg' (sim or real life) it's probably because you're subconsciously applying more back pressure at the point the CEO hangs, this isn't necessary on the NEO due to rotation mode, just takes some getting used to.
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Old 3rd May 2023, 06:08
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Thanks a lot for the very helpful and knowledgeable responses. Really appreciate the quick help!

The Neo is such an amazing aircraft, not just it's economics but also for how sophisticated it is
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Old 8th May 2023, 16:54
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Originally Posted by giggitygiggity
The NEO has Rotation Mode (27-20-10-20) which means that the sidestick commands a pitch RATE demand so the aircraft doesn't hang at 10 degrees (when the tail gets stuck in ground effect).

The CEO doesn't have this mode and it blends from ground mode (sidestick directly commands the elevator) to flight mode (sidestick commands 1g).

For those mentioning it 'jerking up at 10 deg' (sim or real life) it's probably because you're subconsciously applying more back pressure at the point the CEO hangs, this isn't necessary on the NEO due to rotation mode, just takes some getting used to.
Hi, that's not 100% correct.
The CEO also uses a C*Law, so pitch rate at low speed, g load at higher speeds. (Pitch rate feedback gain is slowly reduced with speed, btw. in alternate law pitch rate gain scheduling is a function of flap/slat config)
I hope I could help a bit.

Simon
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