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Forces are forces and any upwards force from the engines can be counteracted by the control surfaces as long as they have enough authority. Boeing's entire problem is trying to do all this with only two flimsy sensors, and compounded by them inexplicably ignoring one of the sensors. The original design was stupid as hell but there's nothing wrong with the general idea of what they are trying to achieve as long as it is implemented competently.



The A320 has "flight envelope protection" which does something much like MCAS except it is much more comprehensive because it is integrated with the fly-by-wire system and can use all control surfaces.

FBW on the A320 has many benefits such as better passenger comfort because it can use the control surfaces to take the edge off turbulence. You can get away with smaller control surfaces which then lowers weight, improves range, etc.

Airbus went through a lot of work to validate the safety of the FBW/Flight Envelope Protection -- if sensors fail, it goes into one of several degraded modes. Pilots are trained to recognize these modes and fly them.

Boeing has applied this technology to their large jets, but it's just sad that the most common Boeing jet by far, the 737, is a technological backwater. Boeing is talking about making a "New Midsize Aircraft" which has a questionable market, but so far as I can tell, their business plan is to be building a starship for NASA in 2070 but still be selling 737s.


Is it fair to say Airbus is better at FBW because they have more experience with it?


And they have an history with FBW-caused accidents.

Especially AF296 killed 3 people when they try to demonstrate the anti-stall capacity of the FBW during an airshow. Airbus modified the way the fbw control reclamation worked after this. After the Rio-Paris accident (forgot the flight name, it was AF too), they changed the way the degradation worked wehn sensor fails (i think now 3 different mode exists, and information is more visible).

Those incident killed people, and there is a chance that the first one was actually caused only by the manufacturer (the second one was 99% the pilot though, the remaining 1% was: better information, better sims and better gradation so that even new, tired pilot can't make this kind of mistake).


There have been plenty of accidents involving the failure of old analog control systems too.

FBW adds cyber-related failure modes, but it is hard if not impossible to make the traditional hydraulics, strings, springs and pully-based systems resilient against failures since the number of things you have to duplicate explodes exponentially.


That AF 296 was caused by FBW is more of a conspiracy theory than anything else. Even if it were true that the pilots applied TOGA power a few seconds before the investigation concluded they did, they were still flying way too low with engines at idle. Poor planning, pilot error.


Boeing's FBW is about as good as Airbus's FBW.

One big difference is that the pilot and co-pilot's yokes on a Boeing plane are mechanically connected to each other so they share the feelings. Airbus uses "sidestick" controllers which aren't quite as nice but are perfectly adequate.

Boeing, however, uses FBW only on their large aircraft, but not on the 737, which is their most flown aircraft. All Airbus planes are FBW, because their competitor to the 737, the A320 is FBW.


GA pilot here; I have no experience flying anything as large as a 737, but the relevant part is ... I fly manual controls (stick and rudder) with electric trimmers. Forces are forces, the trimmers should help you keep the controls at a force level that the regular pilot can still move it in normal flight. A fly by wire is the best solution for large planes with big forces on the control surfaces, but that means a re-certification program that Boeing tried to avoid. The wheel in the cockpit that pilots manually turn, no longer belongs there. It is like power steering on a large truck: you need it and it should be there.

AOA sensors should be helpers, should notify or alert, but never make decisions.


> Forces are forces and any upwards force from the engines can be counteracted by the control surfaces

Only if you ignore moments. [0]

[0] https://en.wikipedia.org/wiki/Bending_moment




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