The terms 'Glass Cockpit' and 'Fly-by-Wire' are often used when discussing today's hi-tech aircraft.  Most of the latest generation of modern airliners are equipped with these technologies and they have been around for some time in military aviation.  These technologies are spin offs from both research into space exploration equipment and the need of the military to develop new technologies that will allow their pilots to get the maximum out of their aircraft.  The modern fighter plane has the capability of flying at supersonic speeds just feet above the ground, hugging the contour of the land or sea.  When an aircraft flies at great speed so close to the ground, the pilot may only have a split second to make a decision to avoid obstacles or to get out of trouble.

 
Fly-by-Wire

Traditionally designed aircraft relied on a combination of mechanical links to transform the pilots commands in the cockpit, into actions by the relevant piece of equipment.  For example; if we look at the control column, it is directly linked to all the operating equipment it controls,  when the pilot moves the control column his/her actions are transmitted via a series of  hydraulic hoses, steel cables or electrical wires to the piece(s) of equipment that will perform the particular manoeuvre.  Every item of control equipment is linked in this manner each with their own dedicated linkages and in critical areas these connections are, for safety reasons, often duplicated or triplicated, so that if one system were to fail there would be a back-up.  However, all these linkages and connections have to be thoroughly checked and serviced at regular intervals and takes some time to complete, also they add weight and take up space.

With the Fly-by-Wire system there are no direct mechanical links between pieces of equipment, everything is computer controlled and linked with wires carrying digital signals.  When the control column is moved it sends a series of coded digital signals to the relevant piece(s) of equipment which is then decoded and acted upon.  In theory, only a single pair of cables would be needed to link all the aircraft's system together, each only decoding the information that was relevant.  As all the connections are via electrical cables it becomes a lot easier and quicker to check their performance when the aeroplane is being serviced, meaning that the aircraft can be back in service in a shorter space of time.  The weight and space gain is also of benefit to operators as electrical cables take up little space and are much lighter than their mechanical predecessors.

The same computers can also be, and are, used to assist the pilot in flying the aircraft and can be used to combine several tasks together, i.e. navigation, autopilot, radar, etc.  In fact with modern technologies it would be possible for an aircraft to take-off, fly to its destination, and land safely, without the need for a pilot.  However, I doubt very much that there would many people queuing to be the first to travel on a pilot-less aeroplane.

The Glass Cockpit

Whereby Fly-by-Wire is the latest technology that the pilot's do not see, the Glass Cockpit is the latest technology that they do.  The Glass Cockpit is the latest technology that replaces the traditional cockpit layout of banks of instruments, levers, switches and dials.  The Glass Cockpit replaces the old technology with computerised keyboards, consoles and monitors, although some traditional features are retained.  Each of the monitors can be switched to one of several displays including duplicating the display from another monitor.  The monitors replace the banks of dials that were standard in traditional cockpits, and can be switched from one task to another very simply and the display chosen would hold the relevant information, for example: the navigation display could hold, as well as navigation information, weather details and flight plan.
 

Traditional Cockpit (Boeing 747)	Glass Cockpit (Boeing 777)

As can be seen in the two comparison pictures, the Glass Cockpit flight deck is a lot less cluttered with fewer and easier to read displays.  The amount of switches dials and levers has also been greatly reduced, giving the flight deck a much more airy feel to it.