Airbus is at it again...

since all that's required is to make the autoflight system respond to the TCAS command to climb or descend, it wouldn't be hard to make the boeings do this either. Especially since there's normally some time before a Traffic Advisory becomes a Resolution Advisory.
 
I'm more or less concerened with making any system to where it has control over the autopilot. I'd rather that "connection" not exist.
 
jangell said:
I'm more or less concerened with making any system to where it has control over the autopilot. I'd rather that "connection" not exist.
I suspect the same logic was applied to autopilots when they were introduced as well. ;)
 
Brian Austin said:
I suspect the same logic was applied to autopilots when they were introduced as well. ;)

Quite possibly.

The problem is when you program these automated systems you can't possibly think of all the scenarios that could evolve which your code will do something very....unwanted.

Take a look at some Airbus related events:
article said:
The downside of this faith in technology soon becomes apparent, however. The following five examples graphically illustrate this.

a. When my brother was assigned captain to the then newly introduced Airbus A 310 - a plane which in the 1980s was considered a high-tech aircraft but today already appears antiquated - he told me about an incident that gave me pause: During the last stage of the final approach, a bolt of lightning struck the nose of the aircraft, damaging the plane's electronic equipment in the process. The confused on-board computer still had a suggestion to make, however, and flashed it on the screen: "Shut down engines."

Now no sensible pilot in the world would do that during this stage of flight, so "Colleague Computer's" suggestion was ignored. The incident itself makes one stop and think, however: Isn't there the danger that at some point in the future the on-board computer will not merely make a suggestion but go ahead and take action itself? Isn't there perhaps even a danger that one day, in keeping with the new philosophy I mentioned earlier, the pilot will only be able to intervene to the extent permitted by the computer? No matter how enthusiastically one may basically embrace technical progress, anyone who has retained any critical perspective at all will find it impossible to answer this question with an unequivocal "no". The following additional examples make it clear that a healthy dose of scepticism is by no means unwarranted.


b. On 14 September 1993, a Lufthansa A 320 crashed in Warsaw while landing on a wet runway in the rain. Due to the strong crosswind, the pilot tilted the plane slightly to the right just before touchdown; it thus touched down first on the right main landing gear and then on the left. As a consequence of the A 320's construction at the time, the spoilers (which changes the airflow round the wings, modifying the lift and thus bringing the plane down to the ground) did not work because the main landing gear on both sides were not fully weighted and the wheels - due in no small part to the aquaplaning effect - were not turning at the programmed speed. In short: According to the logic of the computer, the plane had not yet landed but was still turning. Thus the spoilers, which would create a braking effect, were not to be activated. At that time neither the thrust reversers nor the spoilers of an Airbus A 320 - in contrast to a Boeing 737, for instance - could be manually activated. As a result, the aircraft - braked too slowly and too late - raced towards the end of the runway. The human being (pilot) was helpless.

As if that were not enough, the on-board computer did one more thing: The pilot could not fully activate the thrust reversers to brake the plane because the engine performance had been reduced to a maximum of 71 percent of full reverse thrust in order to protect the engines. A captain friend of mine remarked: "That would not have happened with my B 737."

Conclusion: "The pilot, who in a crisis decides against protecting the engines and in favor of saving the aircraft and human lives, is rendered powerless by the "foresighted" programmer of the system."


Perhaps there are some programmers out there with the foresight for doing this kind of work. I know I surely am not one of them. Nothing I code would I ever allow to be used in a life/death situation like this. I'm not prefect..and I've never met a programmer that doesn't mess up. You simply cannot predict all the things that can make your code to something a human will not like...even though the computer thinks it's doing the right thing.

Imagine this.. Airbus is on final approach..with the autopilot flying the landing...An aircraft on the holdshort line flicks their transponder onto Alt... Airbus plane freaks out trying to avoid the "collision" it detected...and you know what happens next....

I'm sure they would try to eliminate all of these potential issues. But still...You can't think of everything.
 
I'm not fully comfortable with the idea of being on a plane that's landing on auto-pilot, personally. I wouldn't object to this technology being engaged if the plane is at a safe altitude for maneuvering AND AP was engaged, but on an AP approach I'd want this disengaged and a pilot's hand on the controls ready to override, personally.

I work with too much tech to trust it. Cause the programmers can always miss something.
 
jangell said:
I'm more or less concerened with making any system to where it has control over the autopilot. I'd rather that "connection" not exist.

It already exists in Boeings to some extent - Underspeed protection will advance the throttles AND lower the nose to prevent the airplane from stalling. I don't know if similar protection exists for the high side of the envelope.

I'm not so sure this is a big deal - the TCAS system gives LOTS of warning so it's not like pilots could miss it, and at least for the airlines I know of their policy is that pilots must obey the TCAS RA guidance (which I believe is always a pitch adjustment).
 
TMetzinger said:
I don't know if similar protection exists for the high side of the envelope.

Yeah, it does. The airbus won't let you pitch down into a high speed situation, and the Boeing will resist a pitch down.
 
Greebo said:
I'm not fully comfortable with the idea of being on a plane that's landing on auto-pilot, personally.

Well, you eliminate all possibility of a Cat III landing without autoland. Cat II also in most cases.

I work with too much tech to trust it. Cause the programmers can always miss something.

That's why you have to have three autopilots on for each autoland approach, and multiple computers made by different manufacturers programed by different people. Chances for the same failure on two computers at the same time are slim. On all three they are astronomical. I have flown both Boeing and Airbus and have no problems with autoland on either one.
 
I didn't know that the computers on the Boeings were made by different mfrs or had different code. I do believe that the code does go through a line-by-line verification and ungodly amounts of testing, and there are very few changes to flight-control and autoflight systems code
 
Greg Bockelman said:
That's why you have to have three autopilots on for each autoland approach, and multiple computers made by different manufacturers programed by different people. Chances for the same failure on two computers at the same time are slim. On all three they are astronomical.

They said the same thing about the three hydraulic systems on the DC-10. I'm sure Al Haynes would have a few words about that...

And I'd also guess that the three autopilots would have a bigger chance of failure than three hydraulic systems. Yes, you get some positive effects from having them done by three different companies, but I'd bet that if you have a given number of mistakes in the system as a whole, there'd be an elevated chance of having the same mistake in at least two of them. Three, though...

Greg, how often do you fly an entire approach on autopilot? How closely is the captain monitoring? How easy is it to disconnect and hand-fly (red button on the yoke just like us little guys?)

I'll keep riding Boeings when I can. Airbus, on the other hand... I'm not so sure about them any more. Too many things have been going wrong with them. Rudders, nosewheels, who knows what else.
 
flyingcheesehead said:
They said the same thing about the three hydraulic systems on the DC-10.

Apples and oranges.

And I'd also guess that the three autopilots would have a bigger chance of failure than three hydraulic systems.

Don't see how.

Greg, how often do you fly an entire approach on autopilot? How
closely is the captain monitoring? How easy is it to disconnect and hand-fly (red button on the yoke just like us little guys?)

Not very often, that is no fun. :D Very. And yes, just like the little guys. Answers in that order.

I'll keep riding Boeings when I can. Airbus, on the other hand... I'm not so sure about them any more. Too many things have been going wrong with them. Rudders, nosewheels, who knows what else.

To each his own. I have no problems with either. For every Airbus problem, I am sure you can find a Boeing problem
 
Greg Bockelman said:
Don't see how.

I guess my thought is that while it is being designed by three separate companies, you'll tend to get the same errors from different people. I'd also expect that if you had one American company, one Chinese company, and one Indian company that it'd be more reliable than three American companies. (Or three Chinese companies, or three Indian companies.) A sort of genetic diversity, if you will.

To each his own. I have no problems with either. For every Airbus problem, I am sure you can find a Boeing problem

Yes, but I know of several recurring problems with Airbus, and with Boeing I'm blissfully ignorant. :D However, I do have complete trust and confidence in you folks up in the front office to bring the plane down safely if it's anywhere within the realm of possibility.
 
flyingcheesehead said:
I guess my thought is that while it is being designed by three separate companies, you'll tend to get the same errors from different people.

That is why

TMetzinger said:
I do believe that the code does go through a line-by-line verification and ungodly amounts of testing, and there are very few changes to flight-control and autoflight systems code

There has to be some very strict quality control to pass FAA muster.


flyingcheesehead said:
I'd also expect that if you had one American company, one Chinese company, and one Indian company that it'd be more reliable than three American companies. (Or three Chinese companies, or three Indian companies.) A sort of genetic diversity, if you will.

I suppose. But none of that concerns me.

BTW, did you know the Boeing airplanes from the 777 forward are every bit as fly by wire as the Airbus?
 
jangell said:
The problem is when you program these automated systems you can't possibly think of all the scenarios that could evolve which your code will do something very....unwanted.

I wonder if the avoid_cumulogranite_always subroutine has a call from the avoid_other_airplanes subroutine.
 
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