By: mrtotty
- 20th March 2014 at 05:47Permalink- Edited 1st January 1970 at 01:00
Something has possibly been found in the southern Indian Ocean 2500 km south-west of Perth - two pieces of debris, one about 24 m long.
Here's hoping that it is related to the aircraft. We need something to go on because without any leads, the speculation will just ramp up over the next 48 hours then start to die as the media's attention moves elsewhere.
By: charliehunt
- 20th March 2014 at 06:33Permalink- Edited 1st January 1970 at 01:00
Sky has been live from KL for the past week and the story has been their lead for the past 3/4 days but you are right in saying that the story will fade unless there is something concrete to go on.
The Australians are stressing that so far there is nothing to connect the debris with the aircraft but their ships and aircraft together with US aircraft are due in the area now.
The oil rig worker also noted he saw the flames go out and the aircraft continued to fly.
Keep up with the programme...where was the oil rig located and where has the search area focused on based on the Inmarsat data? Why do you think the Malaysians, in collaboration with US and other authorities, are now focusing their attention on the South Indian ocean, and have completely disregarded this so called dubious sighting from an oil rig worker?
As I've said before in a couple of my previous posts, there's no way it could have flown along the Northern corridor without being seen on radar and challenged by multiple countries. Which only leaves the Southern corridor as the most likely route it could have taken to allow it to fly for so long without being detected, and which is supported by the Inmarsat data. The fact that the search is now focused on this region suggests that's what most authorities now believe happened, although it's too early to say if the recent debri sighting is from the flight.
In answer to your question first priority is to fly the plane. I already answered your question when i noted:
....in which case either crew were incapacitated quite suddenly or were incapacitated more gradually whilst struggling simply to control a flight control issue.
Occam's Razor is applied like this:
If the aircraft did not issue a distress call then there was some reason why not. You make an unwarranted assumtion that because pilots were required to issue a distress call therefore they should have been able to... there is no evidence they were able to and it is a mute point because they didn't and would have if they could have.
Garbage. You haven't answered anything at all. All you've repeated is something that we already know, i.e. there was no distress call made. You've jumped to the unlikely conclusion that this was due to a fire that incapacitated both pilots, critical electrical equipment, and yet one that wasn't severe enough to disintegrate the aircraft, but actually managed to keep it flying for a further 6 hours!
I normally only have to explain this slowly for babies and the impaired...
Egyptair Flight 667 was almost finished loading and was about to be pushed back. It is an example of how fast a fire can spread and destroy the cockpit in particular rupture the pressure hull.
Had this aircraft become airborne the evidence would not have been preserved.
Like a baby, you clearly can't see what's wrong with this comparison you're making. You're comparing a cockpit fire that occurred on the ground with one that supposedly occurred in the air. You've even contradicted yourself here. As you say, if the fire occurred in the air, it would have been catastrophic, and not likely to selectively render the cockpit, it's instruments and pilots inactive, i.e. if it was a cockpit fire, like the EgyptAir, then the aircraft wouldn't have flown on for a further 6 hours, and we would have found a debri field by now!
There is evidence of an aircraft sighted on fire high in the sky in the same area at the same time and no other aircraft was lost to explosion and fire at that time, ergo that aircraft was MH370.
Garbage. The only so called "evidence" is an uncorroborated eye witness account, that everyone seems to have discounted. And even it were the case, there would be debri field..duh!
By: Mondariz
- 20th March 2014 at 19:30Permalink- Edited 1st January 1970 at 01:00
Just a note on the fire scenario. I hope people realize such a fire only would last as long as pressure remained in the cabin. In the fire melted through the fuselage (as the Egypt Air 777) the cabin pressure would be lost and that would starve the fire of oxygen. So it's quite possible to have a catastrophic fire in 35.000ft without completely destroying the AC.
By: SimonR
- 20th March 2014 at 20:56Permalink- Edited 1st January 1970 at 01:00
God - there's enough childish bickering in the Burma Spitfires thread without it breaking out here!!
Indeed - I was really enjoying how this thread was going: lots of intelligent discussion and postulation which is in marked contrast with the official news agencies!
Let's keep it civil chaps :-)
New
By: Anonymous
- 20th March 2014 at 21:46Permalink- Edited 10th April 2020 at 19:36
If the route deviation was programmed 12 minutes before the handoff as has been put forward by the authorities, this raises further questions and throws a spanner in the works. Evidently the person who said "allright goodnight" said it in a tone of voice which didn't raise any alarm. Think about it, if there had been some kind of fire/smoke before the new diversion had been programmed, and 12 minutes elapsed between that and the handoff, surely they would have declared an emergency, or at least mentioned something on the radio. The "Electrical Smoke or Fire" checklist is accomplished in about 2 to 3 minutes and if the smoke continues and the source cannot be isolated, the checklist calls for an immediate diversion and landing which would involve a radio call.
By: J Boyle
- 20th March 2014 at 22:22Permalink- Edited 1st January 1970 at 01:00
So it's quite possible to have a catastrophic fire in 35.000ft without completely destroying the AC.
But how long could the AC fly with that kind of damage? My guess is not long enough to make it 1500 miles into the Indian Ocean. At some point a hole caused by a fire would tear apart the airframe.
We're not talking about a Lancaster or B-17 flying at 200 kts at 4000 ft with a good size piece of battle damage.
If I understand the fire theory correctly, the assumption is the crew had the turn pre-programed in case of an emergency (BTW: has anyone asked did the pilot usually do that? Anyone ask former co-pilots? What was company policy?)
A fire broke out, they selected the autopilot mode to use that return to land plan.
Only after doing that, but before they had time to make a 20 second radio call, they passed out and the plane continued onto the Indian Ocean.
Did I get that right?
Sorry, I'm not sure if I buy that. Yes, your first priority is to "fly the ship" (in the words of my ex-instructor) and take it towards land, but I've got to think that either of the pilots would have had time to make a radio call or turn the transponder to 7700. Remember, you have a copilot to help, it's not like some poor guy all alone in a light twin with his hands full.
27Vet...you're a professional airline pilot what do you think?
By: Mondariz
- 21st March 2014 at 06:42Permalink- Edited 1st January 1970 at 01:00
The International Aviation Safety Assessment Program (IASA Program) said the following about onboard fires:
HISTORICALLY, If you have a cabin or cargo fire and aren't able to extinguish it within TWO MINUTES from its
start time you WILL NOT BE ABLE TO EXTINGUISH IT.
FURTHER, if you have an inextinguishable fire you have only FOURTEEN MINUTES to
land/ditch and evacuate. If you fail to do this within that time, the fire will have destroyed the
aircraft!
Also, I don't know if this is pertinent to HM370, but some 'smoke evacuation' checklists calls for the aircraft to be depressurized (at least for cargo flights).
Regarding the pre/re-programed flight path for HM370. This has popped up in the media a few times (although never in official investigation briefings). I simply can't see how they could have that information. Malaysian Airlines' ACARS subscription does not cover those data (only engine RR data). The pilot can manually transmit a new flight plan to HQ, but why on Earth would a rogue pilot do this?
Edit: a fire could also have disabled both transponder and communications before the crew really realized what was going on.
By: Bmused55
- 21st March 2014 at 07:48Permalink- Edited 1st January 1970 at 01:00
Just a note on the fire scenario. I hope people realize such a fire only would last as long as pressure remained in the cabin. In the fire melted through the fuselage (as the Egypt Air 777) the cabin pressure would be lost and that would starve the fire of oxygen. So it's quite possible to have a catastrophic fire in 35.000ft without completely destroying the AC.
OK, Pan AM flight 103, a 747 built much sturdier than the 777, was brought down by a small hole being blown in the side of the fuselage, smaller than the holes in the Egypt Air 777. The effects of pressurisation coupled with aerodynamic forces then tore the plane apart in quick order leaving a very obvious 40 mile long, 20 mile wide debris field. Walkers and farmers are still finding bits to this day.
No such debris has been found yet for MH370
A Hawaiian 737 suffered a small fatigue rupture of the fuselage. The effects of pressurisation coupled with aerodynamic forces then tore a large part of the fuselage off. Without pilot intervention, the plane would have nose dived into the pacific.
At the very least a hole in the fuselage would cause so much drag and slow the plane down, the auto pilot would likely then disengage once the plane is pulled far enough off the level.
So, the idea that a 777 flew for 7 hours with the ACARS system pinging a satellite every hour, with a hole in the fuselage is a ludicrous one.
By: Mondariz
- 21st March 2014 at 08:14Permalink- Edited 1st January 1970 at 01:00
Honestly, you can't in the same argument use the Hawaiian 737 incident and say an aircraft can't fly with ruptured fuselage. Pretty clearly it can.
Southwest Airlines flight 812 (2011): Southwest Airlines Flight 812, from Phoenix-Sky Harbor International Airport, AZ (PHX) to Sacramento International Airport, CA (SMF), diverted to Yuma International Airport, AZ (YUM) after experiencing a rapid depressurization at approximately 34,000 feet.
Upon landing, a 5-foot x 1-foot hole in the crown area was observed on the left side of the airplane, aft of the over-wing exit at the stringer 4L lap joint.
They didn't even notice during flight, and it certainly didn't tear the plane apart. If the pilot doesn't even notice, then the auto pilot wouldn't either.
I understand if you don't believe fire/depressurization scenario for HM370, but calling it ludicrous shows an absolute lack of understanding.
By: Bmused55
- 21st March 2014 at 08:26Permalink- Edited 1st January 1970 at 01:00
Honestly, you can't in the same argument use the Hawaiian 737 incident and say an aircraft can't fly with ruptured fuselage. Pretty clearly it can.
With pilot input, sure, it can.
But you're argument has flaws, some pretty big ones.
You are suggesting a scenario where all on board are incapacitated/killed by a fire. The fire then eats into the fuselage skin in one specific point only, magically not weakening any other structure on the aircraft. The resulting decompression snuffs the fire and the plane continues for 7 hours. Miraculously the systems are still operational enough to pin a satellite and keep the auto pilot working and the fire has not weakened the aircraft structure at all.
On top of all that... the fire was clever enough to program a left turn into the auto pilot/fmc yet not let the pilot know. Then at the same moment disable the transponder and radios, thus stopping the pilots from calling for help. The fire then skipped the computers controlling the auto pilot and went for the passengers, so that they could not call for help.
I find that highly, highly unlikely. Too many points at which the entire scenario falls down.
By: Mondariz
- 21st March 2014 at 08:47Permalink- Edited 1st January 1970 at 01:00
You are reading too much into my post. I simply suggest that some combination of fire/depressurization could have left the plane flying uncontrolled for 7 hours (even without autopilot the plane could stay airborne - airliners are stable aircraft that wants to fly). It's even possible the pilot himself dropped the cabin pressure in a desperate attempt to kill the fire (this is standard procedure on many cargo flights). This is well within the possible and can't be discounted. You should also not put too much faith in the re-programmed Flight Management System theory. This is not in the official debriefing (as I posted above). Malaysian Airlines' ACARS subscription does not cover those data (only RR engine data). The pilot can manually transmit a new flight plan to HQ, but if it was a rogue pilot why would he do this?
The speculations about HM370 following waypoints are not in the official briefing either (in fact the CDA chief earlier dismissed the idea).
By: Bmused55
- 21st March 2014 at 09:36Permalink- Edited 1st January 1970 at 01:00
Of course, we know next to nothing about this flight other than what has been announced. So all theories are just as valid as the next.
Except for those that do not take into account the known facts.
Dropping the pressure is only a possible technique on freighters. It is not a valid technique when you have passengers and I doubt you'll find it in an airlines fire check list. First and foremost because you'll kill the passengers. I find it hard to believe a captain with 33 years experience would resort to such action. Also, why no call for help? Any fire bad enough to knock out communications so quickly would incapacitate the pilots for sure. Not necessarily so the passengers. Someone would have noticed smoke and/or flame. Panic would spread. Not getting any word from the crew, people would try to call for help with their phones. No one did.
If none of the 239 passengers and crew made any attempt to call for help, chances are they were unaware of anything being out of the ordinary. This alone makes a fire improbable. Not impossible, but unlikely. It just doesn't fit the known facts.
As for the reprogramming. 777 pilots on Pprune and another on A.net have stated independently that when you make a flight plan change, ACARS sends a data burst with the new plan to HQ. It has been said that the ACARS transmission, 5 minutes before loss of contact was triggered by a flight plane change.
Due to restrictions at work, I cannot verify the veracity of that information.
By: Mondariz
- 21st March 2014 at 10:16Permalink- Edited 1st January 1970 at 01:00
I don't know the exact sequence of events (nobody does) and you are right, depressurization is not recommended for passenger flights. However, that does not mean a distressed pilot wouldn't try (imagine being in a burning unresponsive aircraft). If I remember correctly the outflow valve will also tend toward open, meaning that malfunctions, possibly by short circuit/fire, could leave the valve open. This gives three possible depressurization scenarios:
1. The pilot drops cabin pressure to quell fire
2. Fire melts hole in fuselage.
3. System short circuit/fire opens the valve
A fourth scenario is an explosion causing 2 or 3 from the above.
Note that mobile phones don't work at 35.000ft - and definitely not above the sea (no mobile system at all).
I don't know the wiring layout of a Boeing 777, so it's hard to estimate how big a fire would be needed to knock out the systems that went offline. Any electrical fire will cause short circuits and you might not need a bonfire if it's in the wrong place. Add pilot mistakes and no series of events is impossible. I have read enough strange accident reports not to rule out anything in advance.
If the ACARS message is confirmed to contain new route information the line of events will change and thus any theory on the likely cause of the accident.
Edit: the ACARS message at 01:07 was a standard 30 minute interval message, it was not triggered. The next scheduled ACARS contact was due at 01:37 and was never sent, so the system went offline sometime between.
Edit II: I thought I would add this:
Hishammuddin Hussein, Malaysia's Defence Minister and acting Transport Minister:
I am aware of speculation that additional waypoints were added to the aircraft’s flight routing. I can confirm that the aircraft flew on normal routing up until the waypoint IGARI. There is no additional waypoint on MH370’s documented flight plan, which depicts normal routing all the way to Beijing.
By: Anonymous
- 21st March 2014 at 13:37Permalink- Edited 10th April 2020 at 19:36
But how long could the AC fly with that kind of damage? My guess is not long enough to make it 1500 miles into the Indian Ocean. At some point a hole caused by a fire would tear apart the airframe.
We're not talking about a Lancaster or B-17 flying at 200 kts at 4000 ft with a good size piece of battle damage.
If I understand the fire theory correctly, the assumption is the crew had the turn pre-programed in case of an emergency (BTW: has anyone asked did the pilot usually do that? Anyone ask former co-pilots? What was company policy?)
A fire broke out, they selected the autopilot mode to use that return to land plan.
Only after doing that, but before they had time to make a 20 second radio call, they passed out and the plane continued onto the Indian Ocean.
Did I get that right?
Sorry, I'm not sure if I buy that. Yes, your first priority is to "fly the ship" (in the words of my ex-instructor) and take it towards land, but I've got to think that either of the pilots would have had time to make a radio call or turn the transponder to 7700. Remember, you have a copilot to help, it's not like some poor guy all alone in a light twin with his hands full.
27Vet...you're a professional airline pilot what do you think?
I agree, I don't think fire was the problem. After the ValueJet and Swissair disasters, aircrew will not play around if there is a hint of an electrical or cargo fire on board. Airconditioning smoke is different and the checklist is considered "abnormal" and not "emergency". As to what happened, we shall have to wait and see whether they find the plane. Adam Air wreckage only turned up over a week after the plane went missing and that was because it crashed in a fairly narrow strait. If this plane went down in the Indian Ocean, it may take years before anything washes up on a beach somewhere.
There is a big difference between AF447/Air India/Egyptair and so on, and this flight. This flight left its intended flight path and apparently flew on for several hours in an unknown direction, and was not tracked by any radar (so we have been told) after the last primary return in the straits of Malacca.
It is about time that real-time tracking and flight data upload are installed, the technology has been there for a while already. The plane I'm flying has onboard wifi which works everywhere I've been so far.
My thoughts go out to the people on board and their poor families, and the press' sensationalism has surely been traumatic for them.
By: AlanR
- 21st March 2014 at 14:05Permalink- Edited 1st January 1970 at 01:00
It is about time that real-time tracking and flight data upload are installed, the technology has been there for a while already. The plane I'm flying has onboard wifi which works everywhere I've been so far.
.
The cost of installing this sort of equipment on aircraft should be minimal. As would the cost of having radio beacons, which would surface if an aircraft comes down in the sea.
Posts: 1,059
By: mrtotty - 20th March 2014 at 05:47 Permalink - Edited 1st January 1970 at 01:00
Something has possibly been found in the southern Indian Ocean 2500 km south-west of Perth - two pieces of debris, one about 24 m long.
Here's hoping that it is related to the aircraft. We need something to go on because without any leads, the speculation will just ramp up over the next 48 hours then start to die as the media's attention moves elsewhere.
That's not to mention the poor families...
Posts: 11,141
By: charliehunt - 20th March 2014 at 06:33 Permalink - Edited 1st January 1970 at 01:00
Sky has been live from KL for the past week and the story has been their lead for the past 3/4 days but you are right in saying that the story will fade unless there is something concrete to go on.
The Australians are stressing that so far there is nothing to connect the debris with the aircraft but their ships and aircraft together with US aircraft are due in the area now.
Posts: 1,578
By: Mondariz - 20th March 2014 at 07:19 Permalink - Edited 1st January 1970 at 01:00
Satellite images behind the current search (2500km SW of Perth). There are SAR aircraft in the area and more on their way.
Posts: 2,619
By: topspeed - 20th March 2014 at 09:22 Permalink - Edited 1st January 1970 at 01:00
http://news.ninemsn.com.au/national/2014/03/20/14/13/objects-found-in-malaysia-airlines-search
Indeed...
Posts: 498
By: Alpha Bravo - 20th March 2014 at 13:12 Permalink - Edited 1st January 1970 at 01:00
Keep up with the programme...where was the oil rig located and where has the search area focused on based on the Inmarsat data? Why do you think the Malaysians, in collaboration with US and other authorities, are now focusing their attention on the South Indian ocean, and have completely disregarded this so called dubious sighting from an oil rig worker?
As I've said before in a couple of my previous posts, there's no way it could have flown along the Northern corridor without being seen on radar and challenged by multiple countries. Which only leaves the Southern corridor as the most likely route it could have taken to allow it to fly for so long without being detected, and which is supported by the Inmarsat data. The fact that the search is now focused on this region suggests that's what most authorities now believe happened, although it's too early to say if the recent debri sighting is from the flight.
Garbage. You haven't answered anything at all. All you've repeated is something that we already know, i.e. there was no distress call made. You've jumped to the unlikely conclusion that this was due to a fire that incapacitated both pilots, critical electrical equipment, and yet one that wasn't severe enough to disintegrate the aircraft, but actually managed to keep it flying for a further 6 hours!
Like a baby, you clearly can't see what's wrong with this comparison you're making. You're comparing a cockpit fire that occurred on the ground with one that supposedly occurred in the air. You've even contradicted yourself here. As you say, if the fire occurred in the air, it would have been catastrophic, and not likely to selectively render the cockpit, it's instruments and pilots inactive, i.e. if it was a cockpit fire, like the EgyptAir, then the aircraft wouldn't have flown on for a further 6 hours, and we would have found a debri field by now!
Garbage. The only so called "evidence" is an uncorroborated eye witness account, that everyone seems to have discounted. And even it were the case, there would be debri field..duh!
Posts: 11,141
By: charliehunt - 20th March 2014 at 14:01 Permalink - Edited 1st January 1970 at 01:00
God - there's enough childish bickering in the Burma Spitfires thread without it breaking out here!!
Posts: 1,578
By: Mondariz - 20th March 2014 at 19:30 Permalink - Edited 1st January 1970 at 01:00
Just a note on the fire scenario. I hope people realize such a fire only would last as long as pressure remained in the cabin. In the fire melted through the fuselage (as the Egypt Air 777) the cabin pressure would be lost and that would starve the fire of oxygen. So it's quite possible to have a catastrophic fire in 35.000ft without completely destroying the AC.
Posts: 400
By: SimonR - 20th March 2014 at 20:56 Permalink - Edited 1st January 1970 at 01:00
Indeed - I was really enjoying how this thread was going: lots of intelligent discussion and postulation which is in marked contrast with the official news agencies!
Let's keep it civil chaps :-)
By: Anonymous - 20th March 2014 at 21:46 Permalink - Edited 10th April 2020 at 19:36
If the route deviation was programmed 12 minutes before the handoff as has been put forward by the authorities, this raises further questions and throws a spanner in the works. Evidently the person who said "allright goodnight" said it in a tone of voice which didn't raise any alarm. Think about it, if there had been some kind of fire/smoke before the new diversion had been programmed, and 12 minutes elapsed between that and the handoff, surely they would have declared an emergency, or at least mentioned something on the radio. The "Electrical Smoke or Fire" checklist is accomplished in about 2 to 3 minutes and if the smoke continues and the source cannot be isolated, the checklist calls for an immediate diversion and landing which would involve a radio call.
Posts: 9,821
By: J Boyle - 20th March 2014 at 22:22 Permalink - Edited 1st January 1970 at 01:00
But how long could the AC fly with that kind of damage?
My guess is not long enough to make it 1500 miles into the Indian Ocean. At some point a hole caused by a fire would tear apart the airframe.
We're not talking about a Lancaster or B-17 flying at 200 kts at 4000 ft with a good size piece of battle damage.
If I understand the fire theory correctly, the assumption is the crew had the turn pre-programed in case of an emergency (BTW: has anyone asked did the pilot usually do that? Anyone ask former co-pilots? What was company policy?)
A fire broke out, they selected the autopilot mode to use that return to land plan.
Only after doing that, but before they had time to make a 20 second radio call, they passed out and the plane continued onto the Indian Ocean.
Did I get that right?
Sorry, I'm not sure if I buy that. Yes, your first priority is to "fly the ship" (in the words of my ex-instructor) and take it towards land, but I've got to think that either of the pilots would have had time to make a radio call or turn the transponder to 7700. Remember, you have a copilot to help, it's not like some poor guy all alone in a light twin with his hands full.
27Vet...you're a professional airline pilot what do you think?
Posts: 1,578
By: Mondariz - 21st March 2014 at 06:42 Permalink - Edited 1st January 1970 at 01:00
The International Aviation Safety Assessment Program (IASA Program) said the following about onboard fires:
HISTORICALLY, If you have a cabin or cargo fire and aren't able to extinguish it within TWO MINUTES from its
start time you WILL NOT BE ABLE TO EXTINGUISH IT.
FURTHER, if you have an inextinguishable fire you have only FOURTEEN MINUTES to
land/ditch and evacuate. If you fail to do this within that time, the fire will have destroyed the
aircraft!
Also, I don't know if this is pertinent to HM370, but some 'smoke evacuation' checklists calls for the aircraft to be depressurized (at least for cargo flights).
Regarding the pre/re-programed flight path for HM370. This has popped up in the media a few times (although never in official investigation briefings). I simply can't see how they could have that information. Malaysian Airlines' ACARS subscription does not cover those data (only engine RR data). The pilot can manually transmit a new flight plan to HQ, but why on Earth would a rogue pilot do this?
Edit: a fire could also have disabled both transponder and communications before the crew really realized what was going on.
Posts: 10,625
By: Bmused55 - 21st March 2014 at 07:48 Permalink - Edited 1st January 1970 at 01:00
OK, Pan AM flight 103, a 747 built much sturdier than the 777, was brought down by a small hole being blown in the side of the fuselage, smaller than the holes in the Egypt Air 777. The effects of pressurisation coupled with aerodynamic forces then tore the plane apart in quick order leaving a very obvious 40 mile long, 20 mile wide debris field. Walkers and farmers are still finding bits to this day.
No such debris has been found yet for MH370
A Hawaiian 737 suffered a small fatigue rupture of the fuselage. The effects of pressurisation coupled with aerodynamic forces then tore a large part of the fuselage off. Without pilot intervention, the plane would have nose dived into the pacific.
At the very least a hole in the fuselage would cause so much drag and slow the plane down, the auto pilot would likely then disengage once the plane is pulled far enough off the level.
So, the idea that a 777 flew for 7 hours with the ACARS system pinging a satellite every hour, with a hole in the fuselage is a ludicrous one.
Enough of the fire stores already.
Posts: 1,578
By: Mondariz - 21st March 2014 at 08:14 Permalink - Edited 1st January 1970 at 01:00
Honestly, you can't in the same argument use the Hawaiian 737 incident and say an aircraft can't fly with ruptured fuselage. Pretty clearly it can.
Southwest Airlines flight 812 (2011): Southwest Airlines Flight 812, from Phoenix-Sky Harbor International Airport, AZ (PHX) to Sacramento International Airport, CA (SMF), diverted to Yuma International Airport, AZ (YUM) after experiencing a rapid depressurization at approximately 34,000 feet.
Upon landing, a 5-foot x 1-foot hole in the crown area was observed on the left side of the airplane, aft of the over-wing exit at the stringer 4L lap joint.
They didn't even notice during flight, and it certainly didn't tear the plane apart. If the pilot doesn't even notice, then the auto pilot wouldn't either.
I understand if you don't believe fire/depressurization scenario for HM370, but calling it ludicrous shows an absolute lack of understanding.
Posts: 10,625
By: Bmused55 - 21st March 2014 at 08:26 Permalink - Edited 1st January 1970 at 01:00
With pilot input, sure, it can.
But you're argument has flaws, some pretty big ones.
You are suggesting a scenario where all on board are incapacitated/killed by a fire. The fire then eats into the fuselage skin in one specific point only, magically not weakening any other structure on the aircraft. The resulting decompression snuffs the fire and the plane continues for 7 hours. Miraculously the systems are still operational enough to pin a satellite and keep the auto pilot working and the fire has not weakened the aircraft structure at all.
On top of all that... the fire was clever enough to program a left turn into the auto pilot/fmc yet not let the pilot know. Then at the same moment disable the transponder and radios, thus stopping the pilots from calling for help. The fire then skipped the computers controlling the auto pilot and went for the passengers, so that they could not call for help.
I find that highly, highly unlikely. Too many points at which the entire scenario falls down.
Posts: 1,578
By: Mondariz - 21st March 2014 at 08:47 Permalink - Edited 1st January 1970 at 01:00
You are reading too much into my post. I simply suggest that some combination of fire/depressurization could have left the plane flying uncontrolled for 7 hours (even without autopilot the plane could stay airborne - airliners are stable aircraft that wants to fly). It's even possible the pilot himself dropped the cabin pressure in a desperate attempt to kill the fire (this is standard procedure on many cargo flights). This is well within the possible and can't be discounted. You should also not put too much faith in the re-programmed Flight Management System theory. This is not in the official debriefing (as I posted above). Malaysian Airlines' ACARS subscription does not cover those data (only RR engine data). The pilot can manually transmit a new flight plan to HQ, but if it was a rogue pilot why would he do this?
The speculations about HM370 following waypoints are not in the official briefing either (in fact the CDA chief earlier dismissed the idea).
Posts: 10,625
By: Bmused55 - 21st March 2014 at 09:36 Permalink - Edited 1st January 1970 at 01:00
Of course, we know next to nothing about this flight other than what has been announced. So all theories are just as valid as the next.
Except for those that do not take into account the known facts.
Dropping the pressure is only a possible technique on freighters. It is not a valid technique when you have passengers and I doubt you'll find it in an airlines fire check list. First and foremost because you'll kill the passengers. I find it hard to believe a captain with 33 years experience would resort to such action. Also, why no call for help? Any fire bad enough to knock out communications so quickly would incapacitate the pilots for sure. Not necessarily so the passengers. Someone would have noticed smoke and/or flame. Panic would spread. Not getting any word from the crew, people would try to call for help with their phones. No one did.
If none of the 239 passengers and crew made any attempt to call for help, chances are they were unaware of anything being out of the ordinary. This alone makes a fire improbable. Not impossible, but unlikely. It just doesn't fit the known facts.
As for the reprogramming. 777 pilots on Pprune and another on A.net have stated independently that when you make a flight plan change, ACARS sends a data burst with the new plan to HQ. It has been said that the ACARS transmission, 5 minutes before loss of contact was triggered by a flight plane change.
Due to restrictions at work, I cannot verify the veracity of that information.
Posts: 1,578
By: Mondariz - 21st March 2014 at 10:16 Permalink - Edited 1st January 1970 at 01:00
I don't know the exact sequence of events (nobody does) and you are right, depressurization is not recommended for passenger flights. However, that does not mean a distressed pilot wouldn't try (imagine being in a burning unresponsive aircraft). If I remember correctly the outflow valve will also tend toward open, meaning that malfunctions, possibly by short circuit/fire, could leave the valve open. This gives three possible depressurization scenarios:
1. The pilot drops cabin pressure to quell fire
2. Fire melts hole in fuselage.
3. System short circuit/fire opens the valve
A fourth scenario is an explosion causing 2 or 3 from the above.
Note that mobile phones don't work at 35.000ft - and definitely not above the sea (no mobile system at all).
I don't know the wiring layout of a Boeing 777, so it's hard to estimate how big a fire would be needed to knock out the systems that went offline. Any electrical fire will cause short circuits and you might not need a bonfire if it's in the wrong place. Add pilot mistakes and no series of events is impossible. I have read enough strange accident reports not to rule out anything in advance.
If the ACARS message is confirmed to contain new route information the line of events will change and thus any theory on the likely cause of the accident.
Edit: the ACARS message at 01:07 was a standard 30 minute interval message, it was not triggered. The next scheduled ACARS contact was due at 01:37 and was never sent, so the system went offline sometime between.
Edit II: I thought I would add this:
Hishammuddin Hussein, Malaysia's Defence Minister and acting Transport Minister:
I am aware of speculation that additional waypoints were added to the aircraft’s flight routing. I can confirm that the aircraft flew on normal routing up until the waypoint IGARI. There is no additional waypoint on MH370’s documented flight plan, which depicts normal routing all the way to Beijing.
So no new flight plan.
MH370 PRESS BRIEFING - 9 MARCH 2014 5:30PM
By: Anonymous - 21st March 2014 at 13:37 Permalink - Edited 10th April 2020 at 19:36
I agree, I don't think fire was the problem. After the ValueJet and Swissair disasters, aircrew will not play around if there is a hint of an electrical or cargo fire on board. Airconditioning smoke is different and the checklist is considered "abnormal" and not "emergency". As to what happened, we shall have to wait and see whether they find the plane. Adam Air wreckage only turned up over a week after the plane went missing and that was because it crashed in a fairly narrow strait. If this plane went down in the Indian Ocean, it may take years before anything washes up on a beach somewhere.
There is a big difference between AF447/Air India/Egyptair and so on, and this flight. This flight left its intended flight path and apparently flew on for several hours in an unknown direction, and was not tracked by any radar (so we have been told) after the last primary return in the straits of Malacca.
It is about time that real-time tracking and flight data upload are installed, the technology has been there for a while already. The plane I'm flying has onboard wifi which works everywhere I've been so far.
My thoughts go out to the people on board and their poor families, and the press' sensationalism has surely been traumatic for them.
Posts: 4,996
By: AlanR - 21st March 2014 at 14:05 Permalink - Edited 1st January 1970 at 01:00
The cost of installing this sort of equipment on aircraft should be minimal. As would the cost of having radio beacons, which would surface if an aircraft comes down in the sea.
Posts: 10,625
By: Bmused55 - 21st March 2014 at 14:09 Permalink - Edited 1st January 1970 at 01:00
As is the usual case. Such expense (even minor expense) will be shrugged off until the authorities mandate such equipment. :(