Airbus flight stability

[teohalfen]

I have been noting that FSlabs A320 is more aerodinamically stable than P3D Boeing aircrafts... Have Airbus aircrafts some kind of automatic inputs to the flight surfaces (ailerons, rudder, elevators) to make them more stable even when in "manual flight"?

Thanks,

Teo Halfen

[Sabine Meier]

Well every input is parsed through a set of computers. We have the ELevator and Aileron Computer (ELAC), Spoiler Elevator Computer (SEC) and Flight Augmentation Computer (FAC). This is what makes the a320 compared to the 737 a fly by wire (FBW) aircraft. The sharklets from fslabs on the a320 and a321 will feature updated software to deal with the new wing design.

[Robin Locher]

Yes and in normal law, you have auto trim. This means the AC will hold this G level. So it will trim automaticly. That means if you have a VS off -700 feet it will hold this, even if you turn.

[Sabine Meier]

Plus it if you release the side stick at a given pitch it will hold that pitch. Same is said for the roll channel the when you let go off the side stick it will hold a certain roll.

[Paul Parkin]

3 hours ago, teohalfen said:

I have been noting that FSlabs A320 is more aerodinamically stable than P3D Boeing aircrafts... Have Airbus aircrafts some kind of automatic inputs to the flight surfaces (ailerons, rudder, elevators) to make them more stable even when in "manual flight"?

Thanks,

Teo Halfen

In normal law it's probably best to consider your inputs as what you'd like the aircraft to do, and it'll sort the rest.

Imagine you turn the aircraft to 10 degree left roll and then release the stick, the aircraft will continue to roll at 10 degrees until you straighten it up again. As Koen said above, this also applies to pitch, which is one of the reasons Airbus prefer you to leave autothrust on.

The downside is that the A320 family seems susceptible to Pilot Induced Oscillation (PIO) due to the pilot not actually directly affecting the flight surfaces. There's a video of this somewhere online of a 'bus landing at Gibraltar all kinds of out of shape because of this! I've also been PAXing on a Wizz A321 on a somewhat calm night (for the UK) into Luton and we gently rocked side-to-side all the way down from AP disconnect to short final.