It's about the GIMME button. If it is supposed to give you an airplane to fly, and it is basically fly by wire, would you care to define what kind of aircraft it should mimic? It could drop you into a direct law that gave the controls the touchy feel of a P-38 configured for stunts or it could mimic a fully loaded C-130 or something in-between.
This aspect of the "conversation" has had me thinking also... since, in everything except Mechanical Backup (a realm of last resort if there ever was one), the fact of the matter remains that some interpretation of the crews input the sidestick is
translated into a control surface movement - the idea of "Direct" really is a misnomer.
From the prior link describing the A330 control laws:
In pitch direct law, elevator deflection is proportional to stick deflection and, in all configurations, max elevator deflection is a function of CG
Am I reading this right - "max elevator deflection is a function of CG", meaning there are still electronically applied limits to what the pilot can demand (in this case, of the elevators)? Sounds like a "law" to me?
Also, my understanding of the side-stick is that the Airbus stick is quite a different design to that of the F-16. The F-16 stick only moves a very small physical deflection and is more of a force sensor (I worked F-16 simulators about 17 years ago!), while the 'bus stick is a position sensor. That in itself though is merely interesting.
As gums has very clearly explained in several posts, FBW control laws are all about constraining the aircraft within an envelope, with the intent of keeping the aircraft from getting into an attitude that is known to be "bad news", however highly agile military fighter jets (and *creative* military pilots) were clearly able to find blank spots outside of the controllable envelope envisaged (the deep stall example for the F-16). It wasn't clear to me whether the control laws were then modified on the Viper to prevent the aircraft getting into this condition...
However the point of the preceding paragraph is to ask a simple question:
Is the Airbus inherently a safer aircraft (not comparing to anything here)
because of the FBW system and associated control laws?
Is is hard to ask that without invoking a comparison, but I am not inviting a A vs B discussion here, or wanting to see one evolve. The point is we have limiting systems in cars for example - traction control, limited slip diffs, rev limiters, ABS brake systems. Presumably these are in place because for the greatest majority of time safety is improved because of them - but I guarantee there are a very few cases where evidence indicates the such a system made some accident worse.
My position is that life is inherently dangerous and we are constantly tossing the dice, aside from sitting in the middle of a large field for your entire existence, there is a level of risk that may lead to harm when we do anything, and in particular any human construct can and at some point will fail in some way and possibly cause harm to someone (buildings fall down, dams fail, cars crash, airplanes stop flying). What Airbus has tried to do is prevent most of the obvious bad things from being allowed, through control laws, but as with any control system, once you exceed the design limits, well, bad things may occur.
It's clear that Airbus has done a pretty good job - there are thousands flying. Obviously this is not to say things cannot be improved. Of course improvements are possible.
But, sadly I suspect (yes, this is WHOLLY opinion) this case will result in findings that indicate some sequence of poor human decisions leading to the aircraft being in a very bad place at entirely the wrong time (I see the phrase "holes in Swiss cheese lining up..." applying). Whether it is then appropriate to blame the computers for not saving the day seems unfair. Somewhat akin to driving my car at 100MPH toward a cliff-edge and then blaming the ABS brakes for not stopping the car in time - I'm sure the system would do the best it could until the wheels leave the ground, at which point I become the passenger... Time will tell.