There is a telling moment in a recent interview Richard Quest of CNN did with an Airbus spokesperson while sitting in the cockpit of the company's 330-200 model, the same one that crashed in the Atlantic on May 31.

Quest is going over with the spokesperson all the incredible features in the giant aircraft, noting that it is controlled by a central computer, which controls the plane automatically, receiving instructions from the pilot on what to do when necessary.

As the spokesperson explained, when there are problems the computer is programmed to automatically degrade functions to the basics. Quest next asked what happens in the event of a complete electrical failure. Does the pilot then have the ability to take over control of the plane completely so he or she can fly it himself without the computer. The spokesperson continues with his story of the back-up systems, in effect avoiding answering the question directly.

Quest asked the same question two more times, getting even more dribble and no answer, before he gave up. I wish he had persisted until he got the answer, which I gleaned from blogging pilots, that the Airbus 330-200 cannot be flown without the computer (note well that the Yemenia Airways crash earlier this week involved an Airbus A310, which does not use fly-by-wire controls).

Yes there are manual controls in the event of a complete failure, but these only help keep the plane flying in some sort of mode until the computers can be restarted from a redundant electrical source. Pilots, or people claiming to be pilots, all say that in training they were not able to keep the plane level but it was flyable for a while. Check out the post on http://comeletsflyaway.blogspot.com There are many more pilot sites to be found using a simple search.

What the posts show is there is a huge debate among pilots about whether digital fly-by-wire systems - such as the one used by Airbus - should be used or not. Many say such systems should have a fall back to complete manual control by the pilot. Others say that computer control, where the computer comes between the pilot and the plane's controls, is reliable and can help avoid pilot errors made when flying such large planes.

Unfortunately this debate has been going on without resolution since fly-by-wire systems were unveiled by Airbus and Boeing during the late 1980s. Fly-by-wire relies on electronic rather than hydraulic or mechanical systems to control the aircraft.

Boeing and Airbus differ on how much control the pilot can have. Boeing is much less trusting of the technology and allows pilots to take over from the computers during an emergency. The Airbus system does not.

It seems to me Boeing has struck the right balance. One only has to realise how often computer technology fails in other areas to realise that in the air there is no second chance. Lives are at stake. While computer-guided flying and automation has probably helped avert many serious accidents, and are designed to have redundant systems in case the main one fails, in the end the final redundant system is the pilot, who can take over in the event of catastrophic loss.

Who knows whether a Boeing fly-by-wire system would have survived in a similar situation to the one that downed the Airbus 330-200? Right now it is speculation. However this debate, the one the pilots are having, should have been more public and transparent. As pilots are split in the debate and if those doubts had been made public I would assume that the airline companies and regulators would not be so keen on fly-by-wire systems that did not give back control to pilots.

That debate is now being reported, rather belatedly, by most media. As is usual, the airline manufacturers using the system are taking the typical corporate defensive posture to protect themselves from suits, rather than admitting there is a divide. It is unfortunate that no proper debate will come about until the public starts making its voice heard on the issue and proper statistics and facts on the advantages and disadvantages of each approach are presented. I am not holding my breath, but it does not mean I will not get on an Airbus 330-200. However I will feel a bit less easy when I sit back in my seat knowing the airplane version of HAL from the 2001: A Space Odyssey film.

Send any comments to Ahmed at elamin.ahmed@gmail.com