Definition of term: "Fly-by-wire"?

[Guest]

I need to settle a discussion with a friend about the term "Fly-By-Wire"!I need pointers to documents or sites with good definitions/explanations of the term in relation to modern aircraft?- How did the term come about?- Changes of definition over the years?- Difference in the implementation in ex. Airbus versus Boeing?Ex:Airbus (and modern mil jets) have "full fledged" FBW, i.e. flight computer adjusts to compensate "environmental changes" when hand flying the aircraft.Boeing doesn't do this, hand flying is hand flying!JTS

[Guest Scott Campbell]

J,FBW simply means there's no physical connection between the stick/yoke and control surfaces. The control is done through a computer system with input from the stick/yoke, pedals, etc. The ocmputer then calculates the best response to make the aircraft do what the input asks for (turn, pitch, yaw, etc).Boeing does have FBW on the 777 and all future commercial aircraft. However, the older aircraft still aren't necessarily hand-controlled, inasmuch as the cables and whatnot just go to actuators that actually control the surfaces. There's far too much force on the surfaces for direct cables to work, so they are all hydraulically or electrically assisted. This is not FBW simply because there's a cable running somewhere other than a computer.

[CactusDx 0]

JTS,Here's a pretty decent Airbus site. Maybe you can find something useful here to help with your discussion.http://www.airbusdriver.net/:-waveMike CollierKPHX[table border=1 bgcolor=#eeeeee][tr][td rowspan=2] http://avsim.com/flightdeck/images/Radar_small.gif[/td][td] America West Airlines and proud to be a Beta Tester of[link:www.jdtllc.com]Radar Contact]The premiere ATC adventure add-on for FS

[B777ER 2,484]

Fly-by-Wire is version 2.0. Version 1.0 was commonly called Fly-by-Seat of Pants.

[michal 44]

>electrically assisted. This is not FBW simply because >there's a cable running somewhere other than a computer. Scott,FBW has nothing to do what is between actuators and flight computers. Both Airbus and Boeing use hydraulics to actually move forces.Don't know the exact definition of FBW but it is commonly understood to be a system whereby pilot's inputs first go to a flight computer which then decides how to move control surfaces.Boeing 777 is FBW but doesn't employ Airbus' flight envelope hard limits. You can say the only difference between Airbus' FBW and 777's is what kind of software they use.Michael J.

[michal 44]

>Boeing doesn't do this, hand flying is hand flying! >All FBW airplanes, Boeing or Airbus can be hand-flown. The only difference between them is what's in the software. Boeing feels that pilots prefer aircraft that handles in a fashion they are used to. Airbus developed different method that make pilots go through 30 days of re-training. But both 777 and Airbus A318+ are definitely FBW. There is no suhc thing as "full-fledged" FBW or partial FBW unless you want to create your own definitions. Michael J.

[Guest Scott Campbell]

>>>electrically assisted. This is not FBW simply because >>there's a cable running somewhere other than a computer. >>Scott, >>Don't know the exact definition of FBW but it is commonly >understood to be a system whereby pilot's inputs first go to >a flight computer which then decides how to move control >surfaces. That's what I said.

[Guest]

Thanks guys!I did a bit of surfing myself, and came over this site:"Computers Take Flight - A history of NASA's Pioneering digital Fly-By-Wire project"http://www.dfrc.nasa.gov/History/Publicati...f/contents.htmlA whole book on the subject!JTS

[Guest UweR]

Hi, a few days ago Apollo software announced their FBW add-on on Avsim

[michal 44]

Scott,I stand corrected.I thought you were implying a presence of direct cable implied this was not FBW. In fact Airbus has such direct cable link in case of complete computer failure. I bet 777 also has something similar.Michael J.

[Jet Tech 31]

Michael,Boeing did make several A/C that where sort of cross breeds in the Fly By Wire game. The 757, 767 and 747-400 all had Cables for the Primary Flight Controls (Elev, Ail and Rudder) but used FBW inputs for the spoiler system. Using Spoiler Computers to run the spoilers electro/hydraulically made the system much more reliable and got rid alot of extra weightRegardsPaul:-cool

[Guest]

I guess that means that FS2002 is strictly a fly by wire system. There is no direct connection from your yoke/joystick to any flight control surface on your aircraft. It definately goes through a computer and the computer moves the appropriate surface. Must be FBWKen

[Guest UweR]

What I remember from that article I mentioned: In the bus the stick input directly commands a flight path change, not a control surface deflection. Flying a curve in a Boeing would require to hold the yoke "turned" and slightly pulled back, in the bus you