WPvsMW
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Boeing Modes vs Airbus Laws

Wed May 08, 2019 1:40 pm

I can't find any conclusive statement that the B787 is "fully FBW" to the level of the Airbus A320 and higher. There are many webpages on sites other than Boeing that state "B787 and B777 are FBW", but from Boeing itself:
https://www.boeing.com/commercial/aerom ... 2012_q1/3/
"takes advantage of FBW innovations" is not the same as "is FBW"... ???

How similar to the Normal / Alternate / Direct Law flight control architecture of Airbus is Boeing's current approach?

How can the Airbus FBW be improved, IOW, can Boeing leapfrog Airbus in the B797 flight control systems?

One way that comes to mind is making the "dashboard" into two large display panels, left and right.... with aux outputs so that spare display panels can be fitted in case a main panel fails, like adding an external display to a notebook PC.
Last edited by qf789 on Sun May 12, 2019 5:07 pm, edited 1 time in total.
Reason: title changed as requested by thread starter
 
BravoOne
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Re: How FBW is the B787?

Wed May 08, 2019 4:05 pm

This is such a broad question perhaps you could narrow it down to specific function of a particular flight control. I remain clueless about the subtle differences between Airbus and 787 applied technology. Both the 777 and 787 are fully FBW so if that's the question, there is the answer. Most of this goes beyond the flight crew knowledge, not with standing the recent MCAS debacle.

FWIW, the new 777X allows for autopilot functions in the Secondary mode. That is new when compared to the existing 777 & 787 architecture that currently exists.
 
stratclub
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Re: How FBW is the B787?

Wed May 08, 2019 8:28 pm

I can answer that the 787 is 100% FBW. Even the nose gear steering is FBW. The differences in control laws between the A320 and the 787? I have no clue.

Your link does not really go into anything technical. It is an article written by sales and deals more with the operational aspects of the aircraft from a humans point of view.

Here ya go. The two links should answer your questions for the most part.
https://en.wikipedia.org/wiki/Fly-by-wire
http://www.askcaptainlim.com/-airplanes ... ystem.html
 
Flow2706
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Re: How FBW is the B787?

Thu May 09, 2019 12:30 am

The control law that is used by Airbus is called C*, the one used by Boeing C*U (I don’t know what the letters stand for). The law used by Airbus results in an aircraft that is flight path stable, I.e. that maintains its attitude when the control input is released. FBW Boeings are speed stable, I.e. they return to their trimmed speed (and maintain it) when the control is released. I have only flown Airbus so far and I quite like the FBW implementation, but I guess the Boeing FBW has some advantages as well (behaves more like a conventional airplane and it’s easier to maintain your speed).
 
Max Q
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Re: How FBW is the B787?

Thu May 09, 2019 1:51 am

WPvsMW wrote:
I can't find any conclusive statement that the B787 is "fully FBW" to the level of the Airbus A320 and higher. There are many webpages on sites other than Boeing that state "B787 and B777 are FBW", but from Boeing itself:
https://www.boeing.com/commercial/aerom ... 2012_q1/3/
"takes advantage of FBW innovations" is not the same as "is FBW"... ???

How similar to the Normal / Alternate / Direct Law flight control architecture of Airbus is Boeing's current approach?

How can the Airbus FBW be improved, IOW, can Boeing leapfrog Airbus in the B797 flight control systems?

One way that comes to mind is making the "dashboard" into two large display panels, left and right.... with aux outputs so that spare display panels can be fitted in case a main panel fails, like adding an external display to a notebook PC.



What does changing the configuration of
the displays have to do with the
FBW system ?
The best contribution to safety is a competent Pilot.


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WPvsMW
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Re: How FBW is the B787?

Thu May 09, 2019 1:55 am

Flow2706 wrote:
The control law that is used by Airbus is called C*, the one used by Boeing C*U (I don’t know what the letters stand for). The law used by Airbus results in an aircraft that is flight path stable, I.e. that maintains its attitude when the control input is released. FBW Boeings are speed stable, I.e. they return to their trimmed speed (and maintain it) when the control is released. I have only flown Airbus so far and I quite like the FBW implementation, but I guess the Boeing FBW has some advantages as well (behaves more like a conventional airplane and it’s easier to maintain your speed).


Thanks, Flow2706, I've been looking for those distinctions, which led me to
https://www.skybrary.aero/index.php/Fly-By-Wire
The "U" in CstarU (C*U) refers to speed, the C for control.

The "Boeing C*U" concept led me to an official Boeing document on B777 FBW.
http://www.davi.ws/avionics/TheAvionics ... Cap_11.pdf
The flight control feedback in the B777 replicates that of the B747.

Turning to A vs. B, one of the obvious differences is that movement of one sidestick doesn't move the other sidestick in Airbus FBW, but in B FBW, movement of the one yoke moves the other yoke.
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WPvsMW
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Re: How FBW is the B787?

Thu May 09, 2019 1:57 am

Max Q wrote:
What does changing the configuration of
the displays have to do with the
FBW system ?


Control feedback can be tactile (sidestick or yoke, rudder/brake pedals) or visual... the FBW computers drive both.
 
BoeingGuy
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Re: How FBW is the B787?

Thu May 09, 2019 3:24 am

Several months ago, I gave a detailed explanation of the 777 and 787 Normal, Secondary, and Direct FBW modes. Let me see if I can find it before spending time writing it out again.
 
BoeingGuy
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Re: How FBW is the B787?

Thu May 09, 2019 3:25 am

WPvsMW wrote:
Max Q wrote:
What does changing the configuration of
the displays have to do with the
FBW system ?


Control feedback can be tactile (sidestick or yoke, rudder/brake pedals) or visual... the FBW computers drive both.


FBW Has nothing to do with the configuration of the displays.
 
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Starlionblue
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Re: How FBW is the B787?

Thu May 09, 2019 9:28 am

WPvsMW wrote:
Flow2706 wrote:
The control law that is used by Airbus is called C*, the one used by Boeing C*U (I don’t know what the letters stand for). The law used by Airbus results in an aircraft that is flight path stable, I.e. that maintains its attitude when the control input is released. FBW Boeings are speed stable, I.e. they return to their trimmed speed (and maintain it) when the control is released. I have only flown Airbus so far and I quite like the FBW implementation, but I guess the Boeing FBW has some advantages as well (behaves more like a conventional airplane and it’s easier to maintain your speed).


Thanks, Flow2706, I've been looking for those distinctions, which led me to
https://www.skybrary.aero/index.php/Fly-By-Wire
The "U" in CstarU (C*U) refers to speed, the C for control.

The "Boeing C*U" concept led me to an official Boeing document on B777 FBW.
http://www.davi.ws/avionics/TheAvionics ... Cap_11.pdf
The flight control feedback in the B777 replicates that of the B747.

Turning to A vs. B, one of the obvious differences is that movement of one sidestick doesn't move the other sidestick in Airbus FBW, but in B FBW, movement of the one yoke moves the other yoke.
https://aviation.stackexchange.com/ques ... er-have-sy


Whether the yokes or sticks move together has little to do with FBW. On Boeing the yokes move together to indicate control movements. On Airbus the sticks don't move at all by themselves. There's just a spring. But again, this doesn't affect the FBW architecture or logic..
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
Lukas757
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Re: How FBW is the B787?

Thu May 09, 2019 11:52 am

BoeingGuy wrote:
Several months ago, I gave a detailed explanation of the 777 and 787 Normal, Secondary, and Direct FBW modes. Let me see if I can find it before spending time writing it out again.


I think it was in this thread:
viewtopic.php?f=5&t=1404075
 
WPvsMW
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Re: How FBW is the B787?

Thu May 09, 2019 1:11 pm

BoeingGuy wrote:
WPvsMW wrote:
Max Q wrote:
What does changing the configuration of
the displays have to do with the
FBW system ?


Control feedback can be tactile (sidestick or yoke, rudder/brake pedals) or visual... the FBW computers drive both.


FBW Has nothing to do with the configuration of the displays.


IMO, it depends on how broadly "FBW" is defined. From the standpoint of systems architecture, yoke/sidestick/pedals/knobs/switches and displays are the human interface with FBW. With no human interface, you don't need pilots. Therefore, a FBW system extends to all interfaces with humans.

Open the pod bay door, HAL.
 
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Starlionblue
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Re: How FBW is the B787?

Thu May 09, 2019 1:21 pm

WPvsMW wrote:
BoeingGuy wrote:
WPvsMW wrote:

Control feedback can be tactile (sidestick or yoke, rudder/brake pedals) or visual... the FBW computers drive both.


FBW Has nothing to do with the configuration of the displays.


IMO, it depends on how broadly "FBW" is defined. From the standpoint of systems architecture, yoke/sidestick/pedals/knobs/switches and displays are the human interface with FBW. With no human interface, you don't need pilots. Therefore, a FBW system extends to all interfaces with humans.

Open the pod bay door, HAL.


I disagree. Yoke, sidestick, pedals and so on are interfaces, and they can be used with FBW or FBC (Fly by cable). FBW or FBC are in the strictest sense the signaling system from the controls to the surfaces, and in a slightly wider but still accepted sense include flight control logic such as envelope protections.
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GalaxyFlyer
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Re: How FBW is the B787?

Thu May 09, 2019 1:23 pm

FBW is defined as control of the flight controls thru computerized paths to the hydraulic actuators. The pilot inputs are to computers which signal the actuators to deliver the surface movements required by the control laws. The PFD and ND are separate as they display FMS data.

GF
 
WPvsMW
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Re: How FBW is the B787?

Thu May 09, 2019 1:58 pm

So... we agree on "it depends upon how FBW is defined". The glass cockpit came before FBW, so there's an argument that FBW is distinct from all interfaces. However, I think (systems architecture view) one definition of FBW includes the interfaces... which no longer have cables, analog wiring, meter servos, etc.
 
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Re: How FBW is the B787?

Thu May 09, 2019 2:09 pm

No, we don’t agree. FBW is how the control surfaces are actuated. That I put data into the FMS, which then uses the autopilot to direct the FBW system to move surfaces doesn’t make the keypad a FBW system component.

But, like most things on A.net, you can define it anyway you want, technically correct or not

GF
 
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Re: How FBW is the B787?

Thu May 09, 2019 3:02 pm

There's no new way to define FBW. You may define it as you may want to, but regardless as to how you want it to be, FBW will always be defined as the driving of flight control surfaces without a direct link to the control inputs.

Whether it is by fibre optics, copper cables etc, if your input goes into a computer that caculates the control deflection needed, it is FBW.
The implementer of FBW can then decide how he wants the stuff to work. Coupled yokes, joysticks with a spring that only feeds into a computer, or a helmet that reads your thoughts. If there's no cable/pulley/rod leading from the thingy in front to the thingy in the back, it probably is an implementation of FBW. Or fly-by-fibre optic. Or fly-by-wifi.

Also, FBW does not imply flight regime protection. Airbus has a hard flight protection law that keeps the computer in command, Boeing has a softer implementation that gives the pilot the final say.
FBW also does not depend on glass screens. While it is true that they normally go together, nothing really prevents you from having steam gauges in an AB, with all the air data computers still working behind the scenes.

Imagine an R/C plane or drone. You control it via remote, that then actuates the servos. You can loop or stall or spin it, or not, depending on the protections built in. But it's still FBW.
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Max Q
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Re: How FBW is the B787?

Thu May 09, 2019 3:54 pm

Concorde was the first civilian FBW
aircraft with its analogue system


No glass cockpit there !
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Starlionblue
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Re: How FBW is the B787?

Thu May 09, 2019 10:33 pm

Max Q wrote:
Concorde was the first civilian FBW
aircraft with its analogue system

No glass cockpit there !


Quite right.

Slightly from left field but the Apollo CSM and LM were digital FBW and flew before Concorde. And they were civilian. Whether they were aircraft is another matter. :D

The Apollo guidance computer was then used in a modified F-8 Crusader test aircraft some years later. This was the advent of digital FBW.
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strfyr51
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Re: How FBW is the B787?

Fri May 10, 2019 1:26 am

the B787 is totally digital, The 777 was a Lot of digital with the ELMS cabinet where it wasn't even a rack of Boxes like the A320 but a rack of Blade cards like the IBM 4090 Mainframe computer, The B787 also has lot of that type of technology. Airbus has a lot of digital as well I would bet that the A350 and the B787 are pretty much Neck and Neck for the moment. I'm not sure the B797 is going to be much less and that the airplane will send Messages to Maintenance when it needs service on the digital realm. I suspect there will be a follow up cable to the Rudder but the Ailerons. Elevators, Spoilers. and flaps will all be FBW I'm not totally sure for the rudder though it could be. Just because of Engine out Flying is why I might be shakey.
 
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Starlionblue
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Re: How FBW is the B787?

Fri May 10, 2019 2:32 am

No need for mechanical cable backup to the rudder anymore. Mechanical rudder control was even dropped from the A330 design once the "Enhanced" version entered production. In case of total electrical failure, a Backup Control Module controls the rudder servos.

Engine out is becoming less of a dramatic situation on newer designs. With an engine out on the A350, you still have all your hydraulics and most of your electrics. Some rudder is fed in automatically to compensate for the yaw asymmetry.
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WIederling
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Re: How FBW is the B787?

Fri May 10, 2019 8:58 am

Starlionblue wrote:
Max Q wrote:
Concorde was the first civilian FBW
aircraft with its analogue system

No glass cockpit there !


Quite right.

Slightly from left field but the Apollo CSM and LM were digital FBW and flew before Concorde. And they were civilian. Whether they were aircraft is another matter. :D

The Apollo guidance computer was then used in a modified F-8 Crusader test aircraft some years later. This was the advent of digital FBW.


The Tupolev ANT-20 from the 1920 had FBW ( electrically actuated rudder/elevator afair )
https://en.wikipedia.org/wiki/Fly-by-wire#History

The German VTOL prototypes were fully analog FBW ( massive application of analog computation.)
VJ101, VAK191, Do31 ( do I remember the type names right ?)
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Max Q
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Re: How FBW is the B787?

Fri May 10, 2019 9:37 am

WIederling wrote:
Starlionblue wrote:
Max Q wrote:
Concorde was the first civilian FBW
aircraft with its analogue system

No glass cockpit there !


Quite right.

Slightly from left field but the Apollo CSM and LM were digital FBW and flew before Concorde. And they were civilian. Whether they were aircraft is another matter. :D

The Apollo guidance computer was then used in a modified F-8 Crusader test aircraft some years later. This was the advent of digital FBW.


The Tupolev ANT-20 from the 1920 had FBW ( electrically actuated rudder/elevator afair )
https://en.wikipedia.org/wiki/Fly-by-wire#History

The German VTOL prototypes were fully analog FBW ( massive application of analog computation.)
VJ101, VAK191, Do31 ( do I remember the type names right ?)




That’s something, Tupolev testing fly by
wire in the ‘30’s


Way ahead of their time
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Max Q
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Re: How FBW is the B787?

Fri May 10, 2019 9:40 am

And interesting that serious consideration was given to using a sidestick on the Concorde with one fitted and tested on a prototype


With all the massive technological leaps Concorde made though that was seen as a step too far
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mmo
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Re: How FBW is the B787?

Sat May 11, 2019 7:58 am

Just a quick comment on the 787/777 you trim for speed but not configuration changes whereas on the Airbus there is no trim required at all. There are a whole host of differences in the way the FBW works and the differences between the Boeing approach and Airbus approach.
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WPvsMW
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Re: How FBW is the B787?

Sat May 11, 2019 12:33 pm

mmo wrote:
Just a quick comment on the 787/777 you trim for speed but not configuration changes whereas on the Airbus there is no trim required at all. There are a whole host of differences in the way the FBW works and the differences between the Boeing approach and Airbus approach.


The is the crux of my question... what are the major differences and what design philosophy governed the differences. Here is the best summary I've found between A Laws and B Modes.
https://www.skybrary.aero/index.php/Flight_Control_Laws

In a transition from A to B, or B to A, what part of piloting has the steepest learning (or unlearning) curve?
 
mmo
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Re: How FBW is the B787?

Sat May 11, 2019 3:19 pm

WPvsMW wrote:
mmo wrote:
Just a quick comment on the 787/777 you trim for speed but not configuration changes whereas on the Airbus there is no trim required at all. There are a whole host of differences in the way the FBW works and the differences between the Boeing approach and Airbus approach.


The is the crux of my question... what are the major differences and what design philosophy governed the differences. Here is the best summary I've found between A Laws and B Modes.
https://www.skybrary.aero/index.php/Flight_Control_Laws

In a transition from A to B, or B to A, what part of piloting has the steepest learning (or unlearning) curve?



The transition might take all of one minute. Other than having to trim for speed, they both fly the same. But, there are some subtle differences. Boeing takes the approach of allowing the pilot to have more "control" of the aircraft. By that I mean, in wind shear recovery on the Airbus, and it's been years since I have flown an Airbus, but the stick is pulled all the way back because you have alpha floor protection. on the Boeing, you pull to the moustache or the max energy line. In essence, you are max performing the aircraft, which on a swept wing aircraft means the wing is in a semi-stalled condition but it producing maximum lift for its configuration. Other differences are on the Airbus if you roll to 45 degrees and let go of the sidestick, it will roll back to 33 degrees. On the Boeing, it stays there. There are a ton of differences, most of which I have forgotten but they are subtle. My PERSONAL preference is the Boeing approach.
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BoeingGuy
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Re: How FBW is the B787?

Tue May 14, 2019 9:09 pm

mmo wrote:
WPvsMW wrote:
mmo wrote:
Just a quick comment on the 787/777 you trim for speed but not configuration changes whereas on the Airbus there is no trim required at all. There are a whole host of differences in the way the FBW works and the differences between the Boeing approach and Airbus approach.


The is the crux of my question... what are the major differences and what design philosophy governed the differences. Here is the best summary I've found between A Laws and B Modes.
https://www.skybrary.aero/index.php/Flight_Control_Laws

In a transition from A to B, or B to A, what part of piloting has the steepest learning (or unlearning) curve?



The transition might take all of one minute. Other than having to trim for speed, they both fly the same. But, there are some subtle differences. Boeing takes the approach of allowing the pilot to have more "control" of the aircraft. By that I mean, in wind shear recovery on the Airbus, and it's been years since I have flown an Airbus, but the stick is pulled all the way back because you have alpha floor protection. on the Boeing, you pull to the moustache or the max energy line. In essence, you are max performing the aircraft, which on a swept wing aircraft means the wing is in a semi-stalled condition but it producing maximum lift for its configuration. Other differences are on the Airbus if you roll to 45 degrees and let go of the sidestick, it will roll back to 33 degrees. On the Boeing, it stays there. There are a ton of differences, most of which I have forgotten but they are subtle. My PERSONAL preference is the Boeing approach.


Actually the Boeing Windshear procedure is to push TO/GA and fly the Flight Director pitch bar, not the Pitch Limit Indicators (aka the eye brows or mustaches). The TO/GA pitch control laws are designed for windshear guidance. You don’t pull up to the mustaches.

On the 777 and 787 if you roll to 45 degrees it won’t stay there, actually. If the airplane rolls past 35 degrees, Bank Angle Protection will give an opposing wheel input and roll the airplane back to about 30 degrees unless you override it. You’ll feel it fight you back if you manually roll the airplane past 35 degrees. It’s giving clear tactile feedback.
 
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Re: How FBW is the B787?

Wed May 29, 2019 6:22 am

stratclub wrote:
I can answer that the 787 is 100% FBW. Even the nose gear steering is FBW. The differences in control laws between the A320 and the 787? I have no clue.

Your link does not really go into anything technical. It is an article written by sales and deals more with the operational aspects of the aircraft from a humans point of view.

Here ya go. The two links should answer your questions for the most part.
https://en.wikipedia.org/wiki/Fly-by-wire
http://www.askcaptainlim.com/-airplanes ... ystem.html


Boeing does not name their architecture Normal , Alternate, and Direct Law. Matter of fact? They Don't even Name it! No Boeing component carries the same weight as Airbus to allow for it, In the Airbus you have the FMGC, ELAC and SEC. Boeing has separate components that do the same job FCC's FMC's.
Airbus had to do what they did so as to not step on Boeing Patents (And Boeing has a damn LOT of them!!) Airbus had to "reverse engineer" Their systems . Boeing Never went down thtr that road. By the time Boeing went all digital? They probably just went to the F-15 Borrowed what they wanted and Built the B787 around it! Using the concepts. That Boeing hadn't gone FBW before? They would have had to stop production of the 747-400, 767, 757 and the 737. Since we already KNOW the 737 has reached it's sunset, the 757, 767 are no longer built for passenger service. The 777 has gone thru MAJOR renovations with Updates going the ELMS cabinets from computer Blades to Micro Technology. The 797 will Pretty much Not only tell us what's wrong with it?
The damn thing will write most of it's OWN Gripes Telling us what's wrong and how to fix it referencing the Maintenance Manual Chapter and Verse.
 
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Starlionblue
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Re: Boeing Modes vs Airbus Laws

Wed May 29, 2019 7:07 am

Boeing does name the FBW control "laws", but they are called Modes. Normal Mode, Secondary Mode, Backup Mode, and finally Mechanical Backup.
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zeke
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Re: Boeing Modes vs Airbus Laws

Wed May 29, 2019 7:36 am

Starlionblue wrote:
Boeing does name the FBW control "laws", but they are called Modes. Normal Mode, Secondary Mode, Backup Mode, and finally Mechanical Backup.


Yes indeed, bit like the difference between autothrust and autothrottle. In control systems engineering the term that is used to describe the system to be controlled is called the plant by control systems engineers (we would call it an aircraft), in terms of its internal dynamical state (state/block diagram). By this is meant a list of numbers (called the state vector) that expresses in quantitative form the effect of all external influences on the plant before the present moment, so that the future evolution of the plant can be exactly given from the knowledge of the present state and the future inputs. This situation implies that the control action at a given time can be specified as some function of the state at that time. Such a function of the state, which determines the control action that is to be taken at any instant, is called a control law (Boeing call it a mode).

As the plant (aircraft) is governed by the same physics, the laws (modes) on how to the block diagrams would be designed, and the feedback into the system are very similar.

In Boeing terms on the 777, the normal mode, the PFC (primary flight computer) supply actuator position commands to the ACE (actuator control electronics), which convert them into an analog servo command. Full functionality is provided, including all enhanced performance, envelope protection, and ride quality features. Secondary mode, the PFCs supply actuator position commands to the ACEs, just as in the normal mode. However, functionality of the system is reduced. For example, the envelope protection functions are not active in the secondary mode. The PFCs enter this mode automatically from the normal mode when there are sufficient failures in the system or interfacing systems such that the normal mode is no longer supported. An example of a set of failures that will automatically drop the system into the secondary mode is total loss of airplane air data from the ADIRU and SAARU. The airplane is quite capable of being flown for a long period of time in the secondary mode. It cannot, however, be dispatched in this condition. It is essentially similar to the Airbus alternate law, which is normal law with protections removed. The third mode is direct mode, the ACEs do not process commands from the PFCs. Instead, each ACE decodes pilot commands directly from the pilot controller transducers and uses them for the closed loop servo control of the actuators. This is essentially similar to direct law on an Airbus.
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BoeingGuy
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Re: Boeing Modes vs Airbus Laws

Wed May 29, 2019 8:41 pm

Starlionblue wrote:
Boeing does name the FBW control "laws", but they are called Modes. Normal Mode, Secondary Mode, Backup Mode, and finally Mechanical Backup.


Not quite. They are Normal, Secondary, Direct.

I described them in detail in a previous thread that another poster pasted above.

No such mode as Mechanical Backup or Backup modes. The 777-200/-300 have unadvertised control cables to two spoilers for roll control only, and the Stabilizer from the Alternate Stab Switches on the throttle quadrant. The 787 and 777X have no cables (the 777X does have mechanical nose wheel steering; the 787 is FBW steering also).
Last edited by BoeingGuy on Wed May 29, 2019 8:50 pm, edited 2 times in total.
 
BoeingGuy
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Joined: Fri Dec 10, 2010 6:01 pm

Re: How FBW is the B787?

Wed May 29, 2019 8:44 pm

strfyr51 wrote:
stratclub wrote:
I can answer that the 787 is 100% FBW. Even the nose gear steering is FBW. The differences in control laws between the A320 and the 787? I have no clue.

Your link does not really go into anything technical. It is an article written by sales and deals more with the operational aspects of the aircraft from a humans point of view.

Here ya go. The two links should answer your questions for the most part.
https://en.wikipedia.org/wiki/Fly-by-wire
http://www.askcaptainlim.com/-airplanes ... ystem.html


Boeing does not name their architecture Normal , Alternate, and Direct Law. Matter of fact? They Don't even Name it! No Boeing component carries the same weight as Airbus to allow for it, In the Airbus you have the FMGC, ELAC and SEC. Boeing has separate components that do the same job FCC's FMC's.
Airbus had to do what they did so as to not step on Boeing Patents (And Boeing has a damn LOT of them!!) Airbus had to "reverse engineer" Their systems . Boeing Never went down thtr that road. By the time Boeing went all digital? They probably just went to the F-15 Borrowed what they wanted and Built the B787 around it! Using the concepts. That Boeing hadn't gone FBW before? They would have had to stop production of the 747-400, 767, 757 and the 737. Since we already KNOW the 737 has reached it's sunset, the 757, 767 are no longer built for passenger service. The 777 has gone thru MAJOR renovations with Updates going the ELMS cabinets from computer Blades to Micro Technology. The 797 will Pretty much Not only tell us what's wrong with it?
The damn thing will write most of it's OWN Gripes Telling us what's wrong and how to fix it referencing the Maintenance Manual Chapter and Verse.


I have no idea what exactly you are trying to say, but almost nothing in your post is accurate.

For example, FCCs are only on the 737, 757, and 767s. They certainly aren’t the same function as the FMCS.

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