Malaysian Airlines MH370 contact lost
"If they end up being switched off then it was a deliberate act , case closed."
They cannot be switched off.
They run automatically from the point at which the aeroplane is capable of moving under its' own power to the moment it cannot.
They cannot be switched off.
They run automatically from the point at which the aeroplane is capable of moving under its' own power to the moment it cannot.
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Just a hunch: if the boxes are ever recovered they will show that the pilots were overcome by some sort of toxic fumes,
Even if the CVR recording from the initial phase of the flight could be recovered, short of lots of coughing or someone within range of a microphone actually mentioning toxic fumes I can't see there being any definitive evidence of this at all.
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rampstalker . . .
I keep saying we cannot and must not blame the crew or the aircraft without 150% proof of the events that took the aircraft to where it is.
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Originally Posted by flightradar
1. sending live data from a/c to satellite is certainly possible with today's technology, thus eliminating the need for a (name your colour)box. However, the cost is likely to be an issue, upgrading the satcom bandwidth, storing the data, all this will be added on to the cost of flying to the general public. The main problem I can see is that such a system can fail or be turned off.
1. sending live data from a/c to satellite is certainly possible with today's technology, thus eliminating the need for a (name your colour)box. However, the cost is likely to be an issue, upgrading the satcom bandwidth, storing the data, all this will be added on to the cost of flying to the general public. The main problem I can see is that such a system can fail or be turned off.
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Originally Posted by trainingwheels
Originally Posted by flightradar
1. sending live data from a/c to satellite is certainly possible with today's technology, thus eliminating the need for a (name your colour)box. However, the cost is likely to be an issue, upgrading the satcom bandwidth, storing the data, all this will be added on to the cost of flying to the general public. The main problem I can see is that such a system can fail or be turned off.
The cost is not the data storage, it is the satellite bandwidth required.
I did a very rough calculation on the AF447 thread (here, but didn't not post the numbers: http://www.pprune.org/tech-log/37643...ml#post4993622).
Back of the envelope, to transmit the FDR and CVR data it would take the equivalent bandwidth of several continuous satcom voice calls (continuous for the flight). The cost of this is roughly comparable to the pilot's salaries for a flight (order of magnitude anyway).
If broadly deployed, there might be quantity discounts. And you could undersample the data _somewhat_. But it would still be expensive.
So then... no price too high for safety, right... but look at it from a different perspective. If you have that amount of extra money to spend on enhancing safety, does live downloading the blackbox data give you the best safety improvement for the money?
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They run automatically from the point at which the aeroplane is capable of moving under its' own power to the moment it cannot.
At least that is what we are now told.
Until quite recently the aircraft manuals had the customary boilerplate language about a 30 minute recording. Now it is at least two hours and there is definitely still a circuit breaker in the cockpit to disable the CVR. In fact, if the crew is involved in a reportable event, we are required to pull the CVR breaker and notify maintenance so that the recording can be harvested.
Hmmm. Wonder if the CVR still runs for ten minutes after you pull the breaker? In a commuter plane overrun into the EVAS they did the shutdown checklist down to the CVR breaker, got interrupted and the cell phone calls to ops and the union were both in the NTSB transcript.
Discussions here and elsewhere leave doubt in my mind whether the legally mandated erase function is any more effective than in the analog CVR days. 'Erased' or overwritten CVR conversations in the past were sometimes 'recovered' using some closely held forensic techniques.
I agree that there might not be much on the MH 370 CVR if it is recovered. However the idea that non-volatile memory chips in cameras, tablets and phones of the pax and crew could yield clues certainly has recent precedents in accident investigations.
See for example:
http://dms.ntsb.gov/public%2F55000-5...7%2F550800.pdf
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Yes. A 10TB RAID6 with a hot spare (so three of eight disks have to fail before you lose data) costs about $5,000. That should hold all the data from all an airline's aircraft for multiple flights before you have to overwrite them.
10TB of satellite data bandwidth costs $$$$$$$$$$$$$$$$.
And a bad guy could still turn it off.
The simple solution would be to add a simple location transmitter like the ones used for cargo containers, which could report position to the airline every few minutes from its own GPS. But a bad guy could still turn it off.
10TB of satellite data bandwidth costs $$$$$$$$$$$$$$$$.
And a bad guy could still turn it off.
The simple solution would be to add a simple location transmitter like the ones used for cargo containers, which could report position to the airline every few minutes from its own GPS. But a bad guy could still turn it off.
Just so you know how much data we're talking about, I did a quick check of a DFDR file I have from a six hour flight (I was investigating a strange engine anomaly on the flight). Six hour flight is a 150 meg file, or roughly 25 meg per hour (and that was an older DFDR, new models record even more). Multiply that by the thousands of airplanes in the air at any time and you're going to quickly overwhelm the available satellite resources. So $billion$ of new capability would be needed for the downlink.
I think a far better path would be improve the availability and 'findability' of the data recorders, along with some mandatory automated downlink of aircraft GPS position data.
I think a far better path would be improve the availability and 'findability' of the data recorders, along with some mandatory automated downlink of aircraft GPS position data.
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I recall years ago thinking the skies were so full of aircraft we could swap data packages. I have no idea how to calculate the percentage of time another aircraft would be available, given the long straight-line distances, but I bet a lot of the time it could be a cheap alternative.
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Just so you know how much data we're talking about, I did a quick check of a DFDR file I have from a six hour flight (I was investigating a strange engine anomaly on the flight). Six hour flight is a 150 meg file, or roughly 25 meg per hour (and that was an older DFDR, new models record even more). Multiply that by the thousands of airplanes in the air at any time and you're going to quickly overwhelm the available satellite resources. So $billion$ of new capability would be needed for the downlink.
Also, most of this stuff is highly optional and it's stored mainly because it can be. 20 years ago standard FDRs on aircraft like the 777 had the capacity to record 64 or 128 words per second (0.77 or 1.54 Kbps). After the expansion of the list of required parameter groups in 2002, Boeing started installing FDRs capable of 3 Kbps.
EICAS and AIMS non-volatile memory
Lots of discussion on the thread about the CVR and the FDR. Naturally we all wish to learn what was recorded.
Yet should not the EICAS and the AIMS have their own memories? My flight manual does not go into that level of detail, but I would imagine that at the very minimum status messages and above are logged--we know that maintenance always looks at AIMS after every flight. Even the most cursory look-through reveals a ton of monitored items.
I am not sure how many parameters are recorded by the FDR although I had once read it is in the hundreds now. Just thinking that AIMS might have something that the FDR does not.
Any Boeing engineers on the thread who can give us a bit more granularity on this?
It might very well be that these systems could be more revealing that the CVR and possibly the FDR.
Hamster, I saw your post after I posted mine. Do you know the size of the parameter list?
Yet should not the EICAS and the AIMS have their own memories? My flight manual does not go into that level of detail, but I would imagine that at the very minimum status messages and above are logged--we know that maintenance always looks at AIMS after every flight. Even the most cursory look-through reveals a ton of monitored items.
I am not sure how many parameters are recorded by the FDR although I had once read it is in the hundreds now. Just thinking that AIMS might have something that the FDR does not.
Any Boeing engineers on the thread who can give us a bit more granularity on this?
It might very well be that these systems could be more revealing that the CVR and possibly the FDR.
Hamster, I saw your post after I posted mine. Do you know the size of the parameter list?
After the expansion of the list of required parameter groups in 2002, Boeing started installing FDRs capable of 3 Kbps.
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For all the talk of data dumps and CVR's uploading in real time a LOT of people seem to be missing certainly 3 issues I can immediately think of....
1. Who stores all these data dumps? I'm 100% certain that CN (to name but one) aircraft will not want their data uploaded to some data centre in Washington State or Virginia.....So you now have the issue of non centralised storage under local jurisdiction and associated variances in collection/storage rules and procedures.
2. Given 1 above how long before certain nations start to insist their data is encrypted prior to uplink and the jurisdiction issues with key release.
3. If anyone doesn't believe that all that data wouldn't be a prime target for some smart/malicious hackers you've not been following what's actually going on in the real world much. I can just imagine some inflight conversation between Captain and FO about a fault on engine 3 being released onto the web and the impact it has on Somenamelessnations National Flag Carrier business.
Location data uploads make sense, some technical data uploaded makes sense, little else is really needed in 99.99999% of the time.
1. Who stores all these data dumps? I'm 100% certain that CN (to name but one) aircraft will not want their data uploaded to some data centre in Washington State or Virginia.....So you now have the issue of non centralised storage under local jurisdiction and associated variances in collection/storage rules and procedures.
2. Given 1 above how long before certain nations start to insist their data is encrypted prior to uplink and the jurisdiction issues with key release.
3. If anyone doesn't believe that all that data wouldn't be a prime target for some smart/malicious hackers you've not been following what's actually going on in the real world much. I can just imagine some inflight conversation between Captain and FO about a fault on engine 3 being released onto the web and the impact it has on Somenamelessnations National Flag Carrier business.
Location data uploads make sense, some technical data uploaded makes sense, little else is really needed in 99.99999% of the time.
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Down loading real time data is just adding another layer of complexity to the systems already in place, if the DFDR/CVR batteries lasted longer then that would be a good and cheap place to start. A simple GPS tracking system installed in a location that it is not possible to locate in flight would cost no more than $1000, i have a system on my car that allows me to track its location from anywhere in the world on a simple app.
If we know where to look we can 99.9% of time find the FDR, this case is unique and unlikely to be repeated, a classic case of the holes lining up in the cheese, it could not happen over central Europe or the US
This will come down to either a bizarre failure that very quickly overcame the crew, yet allowed the aircraft to keep flying for hours on a number of different headings at different levels and disabled the ACARS & transponder, or more likely in my view a deliberate act of an individual who knew how to disable these systems and program a random (non straight line/heading) into a functioning FMC, yet make no demands or leave any trail of prior intent.
If the aircraft was indeed flown deliberately to what is increasing likely its final resting place then the whole event was a suicide mission, with reports of the aircraft having flown as high as FL450 i can only speculate that the intent was to overcome using hypoxia any attempt at someone eventually battering the flight deck door down with an Atlas trolley.
If ? it was a member of the crew, then the loss of face had he come to his senses would probably drive the mission forward, so you climb as high as you can get the aircraft to go at max con thrust, put on your flight deck oxygen, drop the masks, after 15 minutes most are unconscious, after an hour their dead, you then re program the FMC to fly West to a waypoint then turn South with a pre programmed descent to 5000 or lower? select VNAV and set the MCP to altitude to your lower level, the aircraft will stay at the preprogrammed level until reaching your TOD point then descend until it hits the altitude restraint in the MCP and maintain that level until it runs out of fuel.
In the mind of someone acting in what we would see as an illogical manner, they may well see the other passengers and crew as unfortunate collateral damage ( wrong place wrong time), but at the same time may wish to avoid avoidable casualties on the ground (this is not a terrorist act) by ensuring the aircraft would run out of fuel at sea. The culprit then takes off his oxygen mask and joins the rest of the pax and crew on this ghost ship.
He may well figure that the chances of not been spotted are remote, so the they send up the fighters? so what everyone is dead the only change would be the location of the crash should they shoot it down, they fly along side, no one at home, it flying along not towards any centre of population, who will order a shoot down of a T7 with 229 people on board?
In the event the Indonesian military radar controller is too busy watching match of the day or porn, even if he get a radar spot its on a civilian airway no mode C/S doing what aircraft do and assumes the civi people have it in hand?
The whole thing is too deliberate to be random IMHO but guess we will know sooner or later, bizarre
If we know where to look we can 99.9% of time find the FDR, this case is unique and unlikely to be repeated, a classic case of the holes lining up in the cheese, it could not happen over central Europe or the US
This will come down to either a bizarre failure that very quickly overcame the crew, yet allowed the aircraft to keep flying for hours on a number of different headings at different levels and disabled the ACARS & transponder, or more likely in my view a deliberate act of an individual who knew how to disable these systems and program a random (non straight line/heading) into a functioning FMC, yet make no demands or leave any trail of prior intent.
If the aircraft was indeed flown deliberately to what is increasing likely its final resting place then the whole event was a suicide mission, with reports of the aircraft having flown as high as FL450 i can only speculate that the intent was to overcome using hypoxia any attempt at someone eventually battering the flight deck door down with an Atlas trolley.
If ? it was a member of the crew, then the loss of face had he come to his senses would probably drive the mission forward, so you climb as high as you can get the aircraft to go at max con thrust, put on your flight deck oxygen, drop the masks, after 15 minutes most are unconscious, after an hour their dead, you then re program the FMC to fly West to a waypoint then turn South with a pre programmed descent to 5000 or lower? select VNAV and set the MCP to altitude to your lower level, the aircraft will stay at the preprogrammed level until reaching your TOD point then descend until it hits the altitude restraint in the MCP and maintain that level until it runs out of fuel.
In the mind of someone acting in what we would see as an illogical manner, they may well see the other passengers and crew as unfortunate collateral damage ( wrong place wrong time), but at the same time may wish to avoid avoidable casualties on the ground (this is not a terrorist act) by ensuring the aircraft would run out of fuel at sea. The culprit then takes off his oxygen mask and joins the rest of the pax and crew on this ghost ship.
He may well figure that the chances of not been spotted are remote, so the they send up the fighters? so what everyone is dead the only change would be the location of the crash should they shoot it down, they fly along side, no one at home, it flying along not towards any centre of population, who will order a shoot down of a T7 with 229 people on board?
In the event the Indonesian military radar controller is too busy watching match of the day or porn, even if he get a radar spot its on a civilian airway no mode C/S doing what aircraft do and assumes the civi people have it in hand?
The whole thing is too deliberate to be random IMHO but guess we will know sooner or later, bizarre
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Yes. A 10TB RAID6 with a hot spare (so three of eight disks have to fail before you lose data) costs about $5,000. That should hold all the data from all an airline's aircraft for multiple flights before you have to overwrite them.
10TB of satellite data bandwidth costs $$$$$$$$$$$$$$$$.
And a bad guy could still turn it off.
The simple solution would be to add a simple location transmitter like the ones used for cargo containers, which could report position to the airline every few minutes from its own GPS. But a bad guy could still turn it off.
10TB of satellite data bandwidth costs $$$$$$$$$$$$$$$$.
And a bad guy could still turn it off.
The simple solution would be to add a simple location transmitter like the ones used for cargo containers, which could report position to the airline every few minutes from its own GPS. But a bad guy could still turn it off.
Soon all aircraft will be required to transmit Automatic Dependent Surveillance - Extended Projected Profile (ADS-C EPP) which is the standard ADS-C position/altitude report plus "a report containing the sequence of 1 to 128 waypoints or pseudo waypoints with associated contraints or estimates (altitude, time, speed, etc.), gross mass and estimate at Top of Descent, speed schedule, etc. " If ADS-C EPP were to be transmitted every 60 seconds that would probably be all that is needed to locate the aircraft.