An article pondering whether the fly-by-wire system of Airbus was to blame:
http://www.informationweek.com/blog/mai ... SCJUNN2JVN
snippet, lots of links in the article -
It's no secret that commercial airplanes are heavily computerized, but as the mystery of Air France Flight 447 unfolds, we need to come to grips with the fact that in many cases, airline pilots' hands are tied when it comes to responding effectively to an emergency situation.
It's been well established that Air France Flight 447 went down because on-board computers received conflicting information from sensors on the outside of the plane.
But while most reports are focusing on why the sensors gave incorrect information (icing, an electrical fire. etc.), the more substantive issue is that the pilots of Flight 447 never had a fighting chance because their airplane's controls were never in their hands -- they were in the hands of the on-board computers made by the likes of Northrup Grumman, Litton and Honeywell.
Flight 447 was an Airbus, which uses so-called "fly-by-wire" technology that relies entirely on electronic rather than hydraulic and manual systems. Boeing jets also use fly-by-wire, but allow pilots to override computers in an emergency -- whereas Airbus systems don't.
http://www.flightglobal.com/articles/20 ... -a330.htmlFrench investigators have this morning confirmed that automatic messages transmitted by the Air France Airbus A330-200 lost four days ago show that the aircraft was experiencing conflicting airspeed information from its on-board sensors.
The brief statement from investigation agency BEA follows the issuance by Airbus of a telex to operators reminding them of immediate actions to be taken by crews in the event of unreliable airspeed indications.
It says: "Many more or less accurate or attempted explanations of the accident are currently circulating. The BEA reminds one that in such circumstances it is best to avoid any hasty interpretation or speculation based on fragmentary and unvalidated information."
At this stage of the investigation, it says, the only elements established are:
The presence near the planned route of the aircraft over the Atlantic of signifcant convective cells characteristic of the equatorial regions
From the automatic messages transmitted by the aircraft, the inconsistency of the different measured speeds.
The Airbus telex states: "The route of the aircraft was crossing a tropical multicell convective area at the time of the accident. Failure/maintenance messages have been transmitted automatically from the aircraft to the airline maintenance centre.
"The above mentioned messages indicate that there was an inconsistency between the different measured airspeeds. Therefore, and without prejudging the final outcome of the investigation, the data available leads Airbus to remind operators what are the applicable operational recommendations in case of unreliable airspeed indication."
It then provides operations manuals references for the entire Airbus-fielded fleet of aircraft.
A 2001 airworthiness directive previously mandated operators to ensure that aircraft flight manuals were updated with the procedures in the event of unreliable airspeed indications following a series of such events on the type. It indicated that severe icing of the pitot tubes or physical loss of the radome, which additionally requires an increase in power to counter the drag, were potential causes.
Sources in Brazil familiar with the investigative work say that icing is a key focus of investigation.
And from comments of first story, a conflicting opinion:
Good article ... except that it's UTTERLY WRONG.
All Airbus aircraft allow FULL aircraft control as needed, with no computer interference, right down to direct hydraulic control should all electrical systems fail.
See:
http://www.airbusdriver.net/airbus_fltlaws.htmNote that more direct control is automatically given to the pilot as flight systems fail (eg. If the Pitot tubes start giving weird readings).
The real problem Flight 447 had is that the "battle-tested pilot sitting up front" directed it right through the middle of an enormous thundercloud - along with all the turbulence, icing, massive updrafts, hailstones, etc. that are commonly found inside them.
fwiw.