hello,

 

im just curios to what fly by wire is? i know i will be getting the pmdg 777 which does include flw, but im confused to what is actually does.

 

many thanks

In very basic terms, using electronic signals instead of analog cables connected to control surfaces.

 

This Wiki article should give you a good overview.

Also, in short it can prevent the pilots from operating the plane beyond normal limits.

 

For example, on an airbus, if the pilot is stalling the airplane it will throttle up and pitch down on it's own, preventing the stall.

 

Of course that is a simple explaination...

Also, in short it can prevent the pilots from operating the plane beyond normal limits.

 

For example, on an airbus, if the pilot is stalling the airplane it will throttle up and pitch down on it's own, preventing the stall.

 

Of course that is a simple explaination...

 

I don't think this correct. What you describe is flight envelope protection, not FBW per se.

I've always found that expression "fly by wire" kind of confusing, since they literally used wire in the old days too, before they went over to wire. :lol:

I don't think this correct. What you describe is flight envelope protection, not FBW per se.

 

I was always under the impression that with digital FBW (as on the airbus) it was built into the system and considered one in the same...

There are computers in between pilot operated controls and flight controls and engines. The computers get info from sensors all over the aircraft so they know what the aircraft is doing and what the pilot is asking of it, several computers talk to eachother confirming the actions being requested by the pilot can be allowed within the aircrafts safe flight envelope.

 

As the pilot is inputing control movements into a computer, the computer gets info from sensors and the computer in turn operates the required operations initially by electronics to the required electric, hyd or air driven systems ... Hence the term Fly by Wire as your flying in reality using computers via electronics

 

From memory the first Fly by Wire aircraft was the F16 in the 1970's, its party peice was a slow high alpa flypast at slow speeds and angle of attacks never seen before.

 

Happy new year to all

 

Rich

http://en.wikipedia.org/wiki/Fly-by-wire

 

In simple words it's having a computer between the controls and control surfaces instead of having them physically connected.

FBW == You tell the aircraft to do something... it's computer tells it to do something else. Simple.

Here, some real flying by wire...

 

FBW == You tell the aircraft to do something... it's computer tells it to do something else. Simple.

It's exactly the opposite You tell the aircraft to do something, and the computer translates it into control surface movements which cause the aircraft to do exactly that. For example if you want to roll left, you just move the stick/yoke to the left. The computer will compensate for the lift difference of the wings in that position, so you don't sink into the direction of the lower wing. It might be counter intuitive if you have flown classical planes before, but it's still making the aircraft do exactly what you want, not what physics require.

It's exactly the opposite You tell the aircraft to do something, and the computer translates it into control surface movements which cause the aircraft to do exactly that.

 

Yeah... we'll have to agree to disagree on that. Too many Airbus crashes where the FBW systems were taking pilot input and doing something other than what the pilot expected... and the result was catastrophic. So... yep, we'll have to definitely agree to disagree.

Too many?

Yeah... we'll have to agree to disagree on that. Too many Airbus crashes where the FBW systems were taking pilot input and doing something other than what the pilot expected... and the result was catastrophic. So... yep, we'll have to definitely agree to disagree.

Care to back that up with some statistics and examples?

 

Put simply, FBW involves the pilots telling a central computer what to do, the computer then in turn tells the control surfaces what to do. A good example of this is in fighter jets that can now be designed to be inherently unstable to provide more agility, yet still remain controllable, where as in the past if they were that agile, they would have crashed straight away.

 

FBW makes it much easier to control an aircraft in a range of situations from high speed to low speed, high altitude and low altitude, foward CoG and aft Cog, high weights to low weights and handle in a similar manner in all of those scenarios...

 

Regards,

Ró.

At the absolute basic definition level FBW is just electric wires going to the control surface servos instead of hydraulic lines or cables.

 

What's being largely discussed here is flight control augmentation, where you actually are giving control inputs to a computer, which modifies or limits them and then commands the servos. The 777 (and 787 now) has some protections in certain flight regimes but by and large it does not fully augment the controls the way the Airbus FBW system does.