DRIVE BY WIRE SYSTEM

Drive-by-wire, DbW, by-wire, or x-by-wire technology in the automotive industry refers to the use of electrical or electro-mechanical systems for performing vehicle functions traditionally achieved by mechanical linkages/actuators. This technology replaces the traditional mechanical control systems with electronic control systems using electromechanical actuators and human-machine interfaces such as pedal and steering feel emulators. Hence, the traditional components such as the steering column, intermediate shafts, pumps, hoses, belts, coolers and vacuum servos and master cylinders are eliminated from the vehicle. But this is highly used in aviaton industry.

INTRODUCTION

The Fly-By-Wire system was developed for the Boeing 787-8, but can be used for other aircraft too. As

Boeing wanted to give pilots the upper hand, the fly-by-wire systems CAN be disabled and overridden by

pilot inputs. If you would like to use this fly-by-wire script for an Airbus Aircraft, you might want to make a

few changes to give the fly-by-wire more power.

The whole idea here is to get the pilot's control inputs through a nasal script, and creating custom output

properties which are then read by the FDM.

FLY BY WIRE SYSTEM

Fly-by-wire (FBW) is a system that replaces the conventional manual flight controls of an aircraft with an electronic interface. The movements of flight controls are converted to electronic signals transmitted by wires (hence the fly-by-wire term), and flight control computers determine how to move the actuators at each control surface to provide the ordered response. The fly-by-wire system also allows automatic signals sent by the aircraft's computers to perform functions without the pilot's input, as in systems that automatically help stabilize the aircraft.

FUNCTION

The Fly-By-Wire system executes the following functions which help stabilize the aircraft:

Accordingly adjusts thrust and elevators to maintain lift during turns

Helps during turns with rudder movement

Doesn't allow the plane to turn beyond the specified limit

Applies thrust and slightly moves the elevators down when closing in on stall speed

Reduces thrust when exceeding 250 knots under 10000 ft MSL and when reaching above 10000 ft

MSL

Dampens the controls to prevent sudden movements

Automatically holds the current aircraft pitch and roll degree when stick is brought back to the center.

Advantage

Weight savings, lower maintenance costs and greater precision in flying are among the advantages of the fly-by-wire system employed on Airbus jetliners. The weight savings from the replacement of heavy mechanical control cables provides a significant reduction in fuel consumption. In additional, as electrical controls are less complex and easier to maintain than mechanical ones, the use of fly-by-wire translates into lower maintenance costs for operators.

By giving a direct input through electrical signals, commands are much more precise – enhancing overall safety. Furthermore, the control system monitors pilot commands to ensure the aircraft is kept within the flight protection envelope. As a result, the pilot always can get the maximum performance out of the aircraft without running the risk of exceeding safety margins. Fly-by-wire technology has enabled Airbus to develop a true family of aircraft with the highest degree of operational commonality, with nearly identical cockpit designs and handling characteristics. This makes crew training and conversion shorter, simpler and highly cost-effective for airlines – and allows pilots to remain current on more than one aircraft type simultaneously without supplementary takeoff/landing requirements, recurrent training and annual checks.

Disadvantages

It restricts the pilot to monitoring automatic systems. 

System failures are not always noticed in time for a satisfactory reaction. 

System emergencies (when they come) are so unusual that pilots have difficulty reacting correctly.