Page 4 of 10 FirstFirst ... 23456 ... LastLast
Results 61 to 80 of 197

Thread: BREAKING: EgyptAir flight from Paris to Cairo has disappeared from radar

  1. #61
    Senior Member Evan's Avatar
    Join Date
    Jan 2008
    Posts
    5,408

    Default

    Quote Originally Posted by vaztr View Post
    Oz media now citing an ATSB report from 2009 that showed concerns of the window sensor detector unit overheating in 12 Airbuses.

    If the DC2 BUS did die because of this would all radios be disabled? I'm just thinking that if I were PNF I'd be getting a message out about smoke in the plane?
    Or you might be shutting down non-essential busses and killing VHF 3 (ACARS) SATCOM and most of the VHF/HF gear in EMER ELEC CONFIG. They probably still had basic VHF 1 comms but no time to use them. Telling ATC that you are on fire and the cabin is filling with smoke doesn't get you very far.

    To answer your question, the comms are distributed across multiple busses. VHF 3 (ACARS) is on DC 1. VHF 2 is on DC 2. VHF 1 is on the DC ESSENTIAL bus. ACARS itself is on AC 1.

  2. #62
    Member
    Join Date
    Jun 2009
    Posts
    289

    Default

    Quote Originally Posted by KGEG View Post
    Reports are saying the smoke alarms went off for about 3 minutes before the point of impact (or point of possible break up of the structure, just throwing that in there to cover every possibility). In the forward cabin toilet as has been mentioned I think.

    There is a new timeline released by the AVherald:

    Quote Originally Posted by AVherald
    a number of ACARS messages indicating cockpit window temperature sensors faults and optical smoke detector activations were received between 00:26Z and 00:29Z, the crew did not respond to a hand off from Greek to Egypt ATC, the transponder signals of the aircraft ceased at 02:33L (00:33Z) and according to primary radar data provided by Greece's Ministry of Defense the aircraft tracked on its course at FL370 until 00:37Z, then flew a left hand turn of 90 degrees, started a descent doing a right hand orbit until reaching 15,000 feet and disappeared out of radar reach at 10,000 feet

    That would seem like a lot of precious minutes wasted before the crew started their emergency descent if it was a fire.

  3. #63
    Senior Member Gabriel's Avatar
    Join Date
    Jan 2008
    Location
    Buenos Aires - Argentina
    Posts
    5,887

    Default

    Quote Originally Posted by vaztr View Post
    The problem with these detectors is that even when they do 'go off', investigators don't know about it
    They do. They emit an aural alarm "Smoke, smoke!" that get recorded in the CVR.

    --- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
    --- Defend what you say with arguments, not by imposing your credentials ---

  4. #64
    Junior Member
    Join Date
    Jul 2013
    Posts
    62

    Default

    They do. They emit an aural alarm "Smoke, smoke!" that get recorded in the CVR.
    True, we just have to locate the CVR

  5. #65
    Senior Member Evan's Avatar
    Join Date
    Jan 2008
    Posts
    5,408

    Default

    Quote Originally Posted by Gabriel View Post
    They do. They emit an aural alarm "Smoke, smoke!" that get recorded in the CVR.
    I like that in theory, but in reality all you get is crickets.

  6. #66
    Member James Bond's Avatar
    Join Date
    Jan 2008
    Location
    4329'04.4"S 17231'30.7"E
    Posts
    408

    Default

    Seen on PPRUNE

    AirDisaster.com Forum Member 2004-2008

    Quote Originally Posted by orangehuggy View Post
    the most dangerous part of a flight is not the take off or landing anymore, its when a flight crew member goes to the toilet

  7. #67
    Senior Member Gabriel's Avatar
    Join Date
    Jan 2008
    Location
    Buenos Aires - Argentina
    Posts
    5,887

    Default

    Quote Originally Posted by Black Ram View Post
    That would seem like a lot of precious minutes wasted before the crew started their emergency descent if it was a fire.
    I am not sure how an emergency descent would help in a fire situation. But I can think two ways it can make it worse: Oxygen availability and speed.

    --- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
    --- Defend what you say with arguments, not by imposing your credentials ---

  8. #68
    Senior Member Evan's Avatar
    Join Date
    Jan 2008
    Posts
    5,408

    Default

    Quote Originally Posted by Gabriel View Post
    I am not sure how an emergency descent would help in a fire situation. But I can think two ways it can make it worse: Oxygen availability and speed.
    The procedure is for smoke removal and the idea is to get down to an altitude where RAM AIR can be selected to help clear it out. Most of the electrical insulation and thermal insulation is designed to smolder but not ignite so smoke is more the expected danger than fire. The little we know of this incident suggests smoke and possibly breakers tripping or circuits failing in some way. I have yet to see anything that strongly indicates a fire.

  9. #69
    Senior Member
    Join Date
    Jul 2009
    Posts
    1,426

    Default

    BBC report says there is a very deep trench in the Mediterranean where the plane went down. Makes me wonder: How long will the locator beacons sound off this time? They stopped way too early with AF447. Still 30 days?

  10. #70
    Senior Member Gabriel's Avatar
    Join Date
    Jan 2008
    Location
    Buenos Aires - Argentina
    Posts
    5,887

    Default

    Quote Originally Posted by EconomyClass View Post
    BBC report says there is a very deep trench in the Mediterranean where the plane went down. Makes me wonder: How long will the locator beacons sound off this time? They stopped way too early with AF447. Still 30 days?
    1- The requirement is 30 days minimum.
    2- How on Earth do you know how early did the pingers of AF447 stopped? The range of the pingers is not very long, and you have distortion and reflection in different layers of water of different temperature/density. So you need to be deep and close to detect them.
    3- In this case, they have already located at least one of them. Sonically speaking. So as long as it doesn't move, they will find it exactly in the fix they have now.

    --- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
    --- Defend what you say with arguments, not by imposing your credentials ---

  11. #71
    Member James Bond's Avatar
    Join Date
    Jan 2008
    Location
    4329'04.4"S 17231'30.7"E
    Posts
    408

    Default

    Quote Originally Posted by EconomyClass View Post
    BBC report says there is a very deep trench in the Mediterranean where the plane went down. Makes me wonder: How long will the locator beacons sound off this time? They stopped way too early with AF447. Still 30 days?
    Depends on the batteries. Could be as little as 20 days if they haven't been replaced recently.

    I'm hoping Airbus/Boeing will go with this option. Looks good on paper.

    AirDisaster.com Forum Member 2004-2008

    Quote Originally Posted by orangehuggy View Post
    the most dangerous part of a flight is not the take off or landing anymore, its when a flight crew member goes to the toilet

  12. #72
    Super Moderator brianw999's Avatar
    Join Date
    May 2006
    Location
    Tunbridge Wells, Kent. UK.
    Posts
    11,405

    Default

    Quote Originally Posted by Evan View Post
    The procedure is for smoke removal and the idea is to get down to an altitude where RAM AIR can be selected to help clear it out. Most of the electrical insulation and thermal insulation is designed to smolder but not ignite so smoke is more the expected danger than fire. The little we know of this incident suggests smoke and possibly breakers tripping or circuits failing in some way. I have yet to see anything that strongly indicates a fire.
    I'm going to be very simplistic here.
    "There's no smoke without fire". An old but very true saying. There does not necessarily need to be flames present for there to be a fire. Wires and instruments can be damaged by heat to an extent where they no longer operate as required.
    I don't know if the avionics bay of an Airbus is pressurised or not but if it is not then there are there are three things needed for fire to exist. HEAT, FUEL (the wires etc) and OXYGEN. At 37,000 feet there is not a lot of oxygen around. Descend to 12,000 feet and you introduce the final requirement for fire, and by that I mean big, in your face flames to be present. Now, what was previously a smouldering component at 37,000 feet becomes a rapidly spreading fire accelerant.

    The result is sadly currently sitting at the bottom of the Mediterranean.
    If it 'ain't broken........ Don't try to mend it !


  13. #73
    Senior Member Evan's Avatar
    Join Date
    Jan 2008
    Posts
    5,408

    Default

    Quote Originally Posted by brianw999 View Post
    I'm going to be very simplistic here.
    "There's no smoke without fire". An old but very true saying. There does not necessarily need to be flames present for there to be a fire. Wires and instruments can be damaged by heat to an extent where they no longer operate as required.
    I don't know if the avionics bay of an Airbus is pressurised or not but if it is not then there are there are three things needed for fire to exist. HEAT, FUEL (the wires etc) and OXYGEN. At 37,000 feet there is not a lot of oxygen around. Descend to 12,000 feet and you introduce the final requirement for fire, and by that I mean big, in your face flames to be present. Now, what was previously a smouldering component at 37,000 feet becomes a rapidly spreading fire accelerant.

    The result is sadly currently sitting at the bottom of the Mediterranean.
    Allow me to clarify that: when you get an avionics smoke warning and there is detectable smoke in the cockpit or cabin, the DANGER is from smoke more than fire because widespread fire is unlikely due to the nature of the materials used. The greater risk is incapacitation and loss of visibility from smoke. Procedure if significant smoke is detected is to get below pressurization altitude and vent with the RAM AIR. If you are below 200kts you can also open the sliding cockpit windows at that point.

    If you're really on fire, and that fire is in an inaccessible part of the aircraft without fire suppression, your prospects aren't very good in any case. That is why this can never happen.

  14. #74
    Super Moderator brianw999's Avatar
    Join Date
    May 2006
    Location
    Tunbridge Wells, Kent. UK.
    Posts
    11,405

    Default

    Oh yes, you are quite right about smoke being the danger. In 34 years of paramedic service I very rarely came across anyone who burned to death as the press so happily describe it. The cause of death was smoke inhalation and/or poisonous fumes with cremation being a secondary, post death occurrence. The only time where flame fire was the cause of death was in a couple of incidents where a car exploded into flames on impact. The only other incident was a self immolation where the victim poured petrol over themselves and struck a match. I still have the occasional bad dream about that one.

    The Egyptair pilots were in a "Catch 22" situation really. They had to descend to below pressurisation altitude but to do so introduced oxygen to any conflagration and possibly sealed the fate of the aircraft.
    Note the use of the term "possibly". I am offering a possible cause here.
    If it 'ain't broken........ Don't try to mend it !


  15. #75
    Senior Member Evan's Avatar
    Join Date
    Jan 2008
    Posts
    5,408

    Default

    The safety issue remains one of materials flammability, especially concerning wiring and thermal acoustic insulation materials. After Swissair 111, the TSB and FAA took measures to remove metallized polyethylene terephthalate (MPET) insulation. If this turns out to be an in-flight fire involving MPET, we are going to have a larger discussion on our hands.

    In the wake of Swissair 111, the TSB made 23 safety recommendations and some of these remain unfulfilled. There is a lot to this and I'm not going to post it all here. But the build date of this A320 may be significant. According to the FAA, a more stringent flammability test has been mandated for newly built aircraft, and the requirement took effect in September 2005. Both the new Boeing and Airbus planes have advanced electrical-system protection and feature low flammability materials, but the was a 2003 build.

    Quote Originally Posted by PBS
    Commenting on the assertion that MPET (metalized Mylar), the material that added to the fire on Swissair Flight 111, remains in many airplanes, the FAA notes that making the required changes takes time. However, since the June 2005 deadline is just months away, most airplanes will have been modified by now. As for the removal of other insulation coverings in thousands of planes (the majority of the U.S commercial fleet: Mylar in Boeing and Airbus jets, some foam insulation in Airbus, etc.), the FAA says it is considering a proper course of action but feels regulations do not warrant removal of old materials simply because they fail to meet new standards. According to an FAA spokesman, "While not state of the art, these materials"—foam insulation, for instance—"are not unsafe."
    An interesting article here: http://www.cbc.ca/news/aviation-indu...s-say-1.718143

    EDIT: This a/c was delivered new to EgyptAir in 2003 and has always been in their possession. Therefore mandates for removal of MPET insulation by foreign CAA's, notably out-of-range agencies the FAA and the TSB, would not apply and it is entirely possible that the original insulation materials were still in use.

  16. #76
    Senior Member Gabriel's Avatar
    Join Date
    Jan 2008
    Location
    Buenos Aires - Argentina
    Posts
    5,887

    Default

    Quote Originally Posted by brianw999 View Post
    I'm going to be very simplistic here.
    "There's no smoke without fire". An old but very true saying. There does not necessarily need to be flames present for there to be a fire. Wires and instruments can be damaged by heat to an extent where they no longer operate as required.
    I don't know if the avionics bay of an Airbus is pressurised or not but if it is not then there are there are three things needed for fire to exist. HEAT, FUEL (the wires etc) and OXYGEN. At 37,000 feet there is not a lot of oxygen around. Descend to 12,000 feet and you introduce the final requirement for fire, and by that I mean big, in your face flames to be present. Now, what was previously a smouldering component at 37,000 feet becomes a rapidly spreading fire accelerant.

    The result is sadly currently sitting at the bottom of the Mediterranean.
    The Electronics bay is pressurized. So in normal cruise conditions, it would have air with an O2 partial pressure as if you were at 8000ft. You would need to depressurize the plane to "climb" the cabin altitude to 37000 ft, and then you would need to provide O2 to the pax. The amount of O2 flowing through the masks is small, and it will dilute in the general cabin air to levels well below those available at "breathable" altitudes (otherwise instead of masks you would just release the O2 in the cabin). And further, depending the airflow inside the cabin, the slightly "enriched" air may never reach the place where the combustion is occurring. SO I guess that from a "fire" point of view. depressurizing and releasing the masks would be better than descending. But that buys you only so many minutes, because the O2 in the masks last only 15 minutes, so you will NEED to start an emergency descent anyway until 10 minutes or so, or you will kill your pax due to O2 deprivation.

    All that said... Evan has a very good point about smoke.

    --- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
    --- Defend what you say with arguments, not by imposing your credentials ---

  17. #77
    Super Moderator brianw999's Avatar
    Join Date
    May 2006
    Location
    Tunbridge Wells, Kent. UK.
    Posts
    11,405

    Default

    Quote Originally Posted by Gabriel View Post
    ....................SO I guess that from a "fire" point of view. depressurizing and releasing the masks would be better than descending. But that buys you only so many minutes, because the O2 in the masks last only 15 minutes, so you will NEED to start an emergency descent anyway until 10 minutes or so, or you will kill your pax due to O2 deprivation......
    Hence my "Catch 22" comment. My heart goes out to the flight crew. It must be totally soul destroying to work your butt off trying to fix the situation with the gnawing knowledge that you are most likely still going to die along with your passengers whatever you do.
    If it 'ain't broken........ Don't try to mend it !


  18. #78
    Senior Member Gabriel's Avatar
    Join Date
    Jan 2008
    Location
    Buenos Aires - Argentina
    Posts
    5,887

    Default

    Quote Originally Posted by brianw999 View Post
    Hence my "Catch 22" comment. My heart goes out to the flight crew. It must be totally soul destroying to work your butt off trying to fix the situation with the gnawing knowledge that you are most likely still going to die along with your passengers whatever you do.
    I share your sentiments but...
    This isn't necessarily the case here.
    There may be things that the crew may have done wrong and against the established procedures, and that had they done it correctly the outcome may have been much more benign.
    Yes, a lot of "may" there. But... I don't recall a case with smoke, but there were several cases with loss of cabin pressure where the crew, even aware of the situation, didn't don the masks as the first step and started troubleshooting instead. In particular, I very well remember one case where the senior Captain, senior Flight Engineer (it was a 727), and senior Purser were all piled up unconscious in the cockpit, while the junior FO, just out of the flight school, was the only one who followed the procedures, donned his mask immediately, remained conscious, descended the plane, and saved the lives of everybody aboard, including these three senior crew members who quickly regained consciousness after the plane descended low enough.

    As you know, toxic fumes can leave you impaired in seconds (and shortly thereafter, unconscious and then dead).

    --- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
    --- Defend what you say with arguments, not by imposing your credentials ---

  19. #79
    Senior Member
    Join Date
    Jan 2008
    Location
    at 1,600 metres
    Posts
    1,277

    Default

    Quote Originally Posted by James Bond View Post
    Depends on the batteries. Could be as little as 20 days if they haven't been replaced recently.

    I'm hoping Airbus/Boeing will go with this option. Looks good on paper.

    I worked on deployable FDRs in the 70s (for both aircraft and submarines). One minor problem with deployable recorders is that they can float away from an ocean crash site.

  20. #80
    Member
    Join Date
    Jan 2008
    Posts
    124

    Default

    Quote Originally Posted by EconomyClass View Post
    BBC report says there is a very deep trench in the Mediterranean where the plane went down. Makes me wonder: How long will the locator beacons sound off this time? They stopped way too early with AF447. Still 30 days?
    I have sailed round the Med 1nm out of port and the depth sounder just shows E.
    Between Crete and Egypt it is particularly deep 3000m+. Not just a trench.

    https://en.m.wikipedia.org/wiki/Medi...anee_02_EN.jpg
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	image.gif 
Views:	102 
Size:	164.8 KB 
ID:	6381  

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •