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Comment by thisislife2 | Hacker News Reader

I can understand why this would be priority for Airbus even without the incident of a flight losing altitude - recently read that a major philosophical difference between Airbus and Boeing is that Airbus prioritises the safety of the Aircraft through controls (hardware and software) where as Boeing believes a human should always be the final decision maker and be able to over ride any control. An Airbus rarely allows a pilot to over ride any warning or allow the pilot to exceed the specifications of the aircraft, whereas a Boeing will warn the pilot about an unsafe action but will allow the pilot to over ride it. It will be interesting to see how things change when AI tech creeps into Aviation tech.

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It’s an oversimplification to position them as opposites. Airbus uses higher level contol, more a flight path than a control surface movement. But pilots can revert to direct law and have full contol authority when required. Boeing aims for a more traditional control feel, you move control surfaces instead of commanding an outcome. But with layers of substantial augmentation on top of it, up to and including for example the 737 MAX MCAS.

In practice, both approaches blend automation and pilot authority rather than strict philosophical extremes. And the practical difference at the controls is also not as extreme as some people think it is.

There is no oversimplifying happening here. There is no documented procedure to switch to direct law in an Airbus.

In fact, the only way to get into direct law on a fully functional plane is to start pulling circuit breakers for the (redundant) flight computers and inertial reference units.

People might talk about it that way but it's not really the case. It's mechanical limits versus software limits, the later being required because it's a software driven system. The limits may seem artificial and set my humans, but they're no different to "natural" mechanical limitations, in the sense they both stop the pilot from commanding what the machine cannot deliver.

Didn’t workout with the Boeing 737 Max, did it?

That was basically the first Boeing that went in the Airbus direction.

Crucially, while trying to convince everyone that it’s basically the same old 737 to save on pilot retraining costs, nevermind the significantly larger engines.

Airbus is much more transparent about its automation. Pilots even learn about the procedure to fly an A320 with a complete fly-by-wire outage using only mechanical emergency elevator controls and differential thrust.

> Airbus is much more transparent about its automation.

Airbus is OK, but could be better. There is a long history of Airbus crews facing unexpected corner cases in their flight control laws, and fortunately only a few of them have had fatal outcomes. While there are only a few "major" modes, there are a surprisingly large number of edge cases that can be encountered.

That wasn't just automating... That was hiding the features from the manuals to avoid having to re train the flight crews.

No it wasn't. See also: MD-11, 737NG, 777, 787.

The 777 and 787 before it are true fly-by-wire designs like the Airbus in question here; the 737 MAX isn't and never was. It just had a computer that was supposed to add artificial inputs under a very specific condition, so it could continue to fly like the older models under the same type certificate and not require extra pilot training. It turns out that the condition could be triggered erroneously, and the logic to determine the artificial inputs was deeply flawed.

The 737NG already had computer controlled feedback to the control columns, the MAX added computer controlled spoiler deployment (like the 757 and 767) and elevator trim.

The issue could have been avoided if MCAS was made properly redundant (and not rely on single sensor, wtf) and pilots were trained on it. It was all about the money. The airframe is fine.

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