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The way it works for the Airbus is that the pilot controls the plane, but there are safety parameters that determine what the controls do. Consider it like a m
by t0mas88 3y ago
The way it works for the Airbus is that the pilot controls the plane, but there are safety parameters that determine what the controls do.
Consider it like a modern car with engine management software. If you floor the accelerator all at once from a low rpm in a very old car, the engine will stumble, if you do it in a modern car the engine management software will inject the maximum amount of fuel that can be burned and not too much, getting you maximum acceleration.
The same applies for the way Airbus controls work. Let's say you want the maximum climb (for example due to wind shear on landing), in the Airbus you push the throttles all the way forward, and pull the stick all the way back. The computer will figure out not to pitch you up further than the plan can handle.
The same manoeuvre in a Boeing means you press the TO/GA switch twice for maximum power (because the engines are computer controlled here as well) but then you pull back on the yoke up to stick shaker activation (stall warning) and manually try to pitch just below the maximum. There is no safeguard stopping you from pulling too far and stalling the airplane. Every pilot can do that, small training aircraft that everyone learns this in don't have any protections either. But the accuracy won't be as good as what the Airbus computers can do and it requires paying more attention.
Now in an emergency, systems failures, the Airbus will downgrade to how the Boeing works. Full back stick will be an unlimited pitch-up and the pilots need to manually figure out what the maximum is.
- Night_Thastus 3y ago>Now in an emergency, systems failures, the Airbus will downgrade to how the Boeing works. Full back stick will be an unlimited pitch-up and the pilots need to manually figure out what the maximum is. You're referring to Alternate Law and the more extreme version, Direct Law. One note is that it's not always an emergency that can cause this. If important sensors like AOA or airspeed disagree (for example, due to a temporarily-frozen pitot tube), that will also reduce to alternate or direct depending on the situation. Unfortunately this can bite pilots badly if they either don't notice or don't understand the new situation quickly enough. There have been one or two crashes attributed to this over the years. [See Air France 447]
- V__ 3y agoI went down a youtube rabbit hole about aircraft investigations once. One think I am still surprised by is the (in my opinion) bad UX of some errors. For example: It can be really easy to not notice a change from normal to alternate or direct law, if there are multiple problems going on at once.