Dan Gould Posted June 4, 2009 Report Share Posted June 4, 2009 From the NYT: Without the black boxes containing the plane’s voice and data recorders — which officials say may never be recovered the from the ocean — the only clues besides the scant debris exist in the series of 10 satellite signals. The pilot sent a manual signal at 11 p.m. local time indicating that the plane was passing through an area of black, electrically charged cumulonimbus clouds, usually containing lightning and violent winds, according to The Associated Press. The news service, quoting an unidentified aviation official, presented a chilling timeline of events in the cockpit that reveal the plane’s ensuing problems within a 14-minute span, but not what caused them. About 10 minutes after the manual signal, the plane sent out a series of automatic messages to indicate the autopilot had disengaged, a computer system had switched to alternative power and that controls to keep the plane stable had been damaged. About three minutes later, more automatic messages reported the failure of systems to monitor air speed, altitude and direction. The last automatic message, which was received at 11:14 p.m. local time, signaled a loss of cabin pressure and complete electrical failure. The description is quite harrowing, what I can't understand is why these automated messages, designed to give a "heads up" to maintenance personnel so that they have an idea of what needs to be repaired or looked at when the plane lands, would include a notification that autopilot had disengaged? Doesn't seem to me an issue for maintenance personnel to get advanced word about. Quote Link to comment Share on other sites More sharing options...
Soulstation1 Posted June 4, 2009 Report Share Posted June 4, 2009 Sad story I do not like to fly in airplanes Quote Link to comment Share on other sites More sharing options...
Matthew Posted June 4, 2009 Report Share Posted June 4, 2009 It's scary indeed. I've been traveling a lot recently, and I always comforted myself saying: "Planes never go down in the ocean." Quote Link to comment Share on other sites More sharing options...
AndrewHill Posted June 5, 2009 Report Share Posted June 5, 2009 RIP to all on this flight. What a tragedy. Quote Link to comment Share on other sites More sharing options...
Claude Posted June 5, 2009 Report Share Posted June 5, 2009 The description is quite harrowing, what I can't understand is why these automated messages, designed to give a "heads up" to maintenance personnel so that they have an idea of what needs to be repaired or looked at when the plane lands, would include a notification that autopilot had disengaged? Doesn't seem to me an issue for maintenance personnel to get advanced word about. It's also strange that the plane does not send a position signal when flying in an off-radar zone. Quote Link to comment Share on other sites More sharing options...
Dan Gould Posted June 5, 2009 Author Report Share Posted June 5, 2009 The description is quite harrowing, what I can't understand is why these automated messages, designed to give a "heads up" to maintenance personnel so that they have an idea of what needs to be repaired or looked at when the plane lands, would include a notification that autopilot had disengaged? Doesn't seem to me an issue for maintenance personnel to get advanced word about. It's also strange that the plane does not send a position signal when flying in an off-radar zone. But that's an operational flaw for over-water flights, not a technical problem. SOP is to report position when passing a handful of navigational beacons, as I understand it. Quote Link to comment Share on other sites More sharing options...
Soulstation1 Posted June 8, 2009 Report Share Posted June 8, 2009 24 bodies recovered and a piece of the tail section found Quote Link to comment Share on other sites More sharing options...
sidewinder Posted June 9, 2009 Report Share Posted June 9, 2009 This incident has most definitely shaken me up. Was just starting to read an investigative book about the 1974 Turkish Airlines DC-10 airline crash over France (Orly) on the very night this happened. Current best theory is blockage of a pitot tube leading possibly to confused air data, incorrect speed setting for altitude/level of turbulence, automatic disengagement of autopilot and reversion to 'manual' flight with progressive breakup due to speed/turbulence (possibly severe overspeed leading to nose down attitude?). Original lightning strike theories possibly contributory but unlikely to be the main cause. With the tail section found, it is now more likely that they will locate the FDR and CVR. Quote Link to comment Share on other sites More sharing options...
Dan Gould Posted July 2, 2009 Author Report Share Posted July 2, 2009 Inquiry Finds French Flight Struck Ocean Intact It seems hard to imagine, but with the flight striking the water belly first (among the evidence is that shelves in the galley compressed to the bottom) and with the lack of any distress call, is it actually possible this was a case of Controlled Flight Into Terrain - the terrain being the Atlantic Ocean? It seems hard to imagine unless there was a total loss of flight data inputs especially altitude. I've never heard of a plane falling out of the sky yet landing in an essentially normal flight attitude, as opposed to going nose-in. Quote Link to comment Share on other sites More sharing options...
sidewinder Posted July 2, 2009 Report Share Posted July 2, 2009 Certainly seem to indicate a loss of situational awareness out of the cockpit - possibly along with lack of awareness/invalid indication of altitude and air speed, with the autopilot decoupled, reversionary manual control in use and with the chief pilot tucked up in the back asleep and with the co-pilots at the controls (I believe that Air France's findings seem to indicate this). Findings so far point to a tragic sequence of events, which taken together cumulatively increased the risk of catastrophe. Quote Link to comment Share on other sites More sharing options...
Dan Gould Posted July 2, 2009 Author Report Share Posted July 2, 2009 Well the autopilot is supposed to shut off when it received contradictory flight information. It can't operate the plane if it doesn't know airspeed or attitude. Its hard to imagine losing 35,000 feet of altitude without knowing it but then again it happened at night. If it really was CFIT it would be tragic in that they would have known they were so close to the water had it happened in daylight. Quote Link to comment Share on other sites More sharing options...
sidewinder Posted July 2, 2009 Report Share Posted July 2, 2009 Well the autopilot is supposed to shut off when it received contradictory flight information. It can't operate the plane if it doesn't know airspeed or attitude. Its hard to imagine losing 35,000 feet of altitude without knowing it but then again it happened at night. If it really was CFIT it would be tragic in that they would have known they were so close to the water had it happened in daylight. Combine night-time conditions with zero vis out of the cockpit due to severe storm plus (and we don't know this) the possibility that weather radar was out of action and possibly main flight instruments too. They would then be effectively flying blind with high pilot stress/high workload so the scenario doesn't seem unlikely - at least for me. Quote Link to comment Share on other sites More sharing options...
Dan Gould Posted July 2, 2009 Author Report Share Posted July 2, 2009 Yes, except for the fact that there was no communication with ATC, or for that matter, Air France mechanics if they wanted help troubleshooting whatever was happening. I would think anything like a complete instrument failure would trigger some sort of call, distress or not. If it really was CFIT, there was a lengthy time where the plane deviated from 35000 feet - is it really possible they never perceived a situation worthy of contacting ATC? One possibility I hadn't considered is that final plunge might have been triggered by a microburst - which would be a first, a microburst crashing an aircraft that is supposed to be at cruising altitude. BTW, it might not be right to say main flight instruments out since Airbus aircraft have the nifty design feature of a small turbine that drops down into the airflow and is supposed to power up critical instruments and control surfaces. But if airspeed indicators are off ... Its really a unique set of circumstances that will probably never be fully understood. Quote Link to comment Share on other sites More sharing options...
_forumlogo.png.a607ef20a6e0c299ab2aa6443aa1f32e.png)
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.