User Interface Issues and Automated Flight Control on the A320
Warning! These are notes from a short student talk on this subject.
The data herein has not been verified. As the conclusions suggest,
most of the problems observed herein have to do with user interface
issues rather than problems with the concept of fly-by-wire. Thanks
to some helpful readers for pointing this out
- Source: ???
- Original by Lea Wittie and Ryan Gerling (students)
- Some reformatting by Sam Rebelsky
- Note: at least one commentator who found this page
has noted that the problems are overstated and recommends that
those interested in finding out the real issues talk with pilots
who fly A320s about them. [Added 10 April 2000]
- The A320 is an airplane with automated flight control.
- It uses a "fly by wire" system. The pilot's main interactions
are with a computer, not with the plane. The pilot is surrounded
by screens with flight data (airspeed, altitude, ...). Flying
involves programming instructions on the computer. The computer
makes use of facts like fuel efficiency and aifcraft safety to
present safe and economical choices to the pilot.
- There is NO manual override on this aircraft
- There have been 3 major crashes with A320s.
- 1) Pilot confused the data screens for flight-path-angle and
vertical-speed). The plane went down into the side of a
- 2) Strasboug: The plane decended much too quickly on landing
and smashed into the ground about 15 feet before the start of the
- 3) While testing an A320, a pilot attempted to override the
computer and had to rip out wires to do so. One feature which
escaped the override attempt caused a crash when the pilot dove
the plane towards the ground and tried to pull up at the last
second. The computer refused to let the plane pull up and it
crashed into a group of onlookers.
- There are built in landing maneuvers; one of the common ones
had a defect. It caused abnormal behavior of the altimeter (you
thought you were higher up that you actually were).
- The warning system went into effect only a few seconds before
impact and was not even present on all planes.
- The monitors look alike and flight-path-angle and
vertical-speed have the same format (easily confused).
- It's hard to see long term patterns using the computer data.
- The pilot is either EXTREMELY busy or EXTREMELY bored and
during the flight they get a false sense of security (glass
- Error and warning messages during data entry are often
indecipherable and pilots often ignore them.
- Different pilots use different data entering methods; its hard
to switch pilots all of a sudden.
- The crashes were caused by inept pilots (duh!!)
- France put a warning device on its international flights to say
when the plane descended too quickly. They felt this device was
unnecessary on national flights because their pilots knew the
terrain well. (The pilot recieved a two second warning before
the craft smashed into a mountain side.)
[This is not unique to the A320]
- The AIRBUS industry advised all companies using the A320 not to
use the faulty landing maneuver.
- Investigate the crashes rather than immediatly blaming the
- Fix the faulty landing maneuver and the timing on the warning
system. (Better planning)
- Make a better, more self-explanatory monitor display.
- Better, more explictit error and warning messages. Standardized
data entry methods.
- Fix the glass cockpit syndrome. Any ideas??
- Train the pilots more.
- Too much automation may be a bad thing!! (Even the toilet
flushes are computer controlled)
- User interface is important.
- Bugs should be fixed, not ignored.
- Manual override is a good thing.
- "After 4 years in service, and 600,000 flying hours, the A320
has scored 3 major accidents and 177 lives lost. In 11 years, the
Boeing 757 has flown 4 million hours with no fatalities." Don't
worry, just pilot error