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View Full Version : Why is sat - inflight data backup not used ?


carlo321
12th Jan 2015, 05:29
With Airasia, again FDR's must be searched at the bottom of the seas. (MH307- AF447) - these operations cost millions. The techniques of FDR are 50 years old and outdated. Today all cruise ships use high speed internet at middle of the oceans(for leisure) - hunters use satellite com at the artic or in the jungles.
Millions of Apple clients worldwide, can use Apple cloud backup... but for the safety of airliners, these techniques are too expensive ??
At the year 2015 I do not take such excuses; it cannot be expensive to backup for ex. the last 30 mins of flight data and comms via low orbit satcom satellites, not even for the 12000 airliners simultaneously in our skies each moment. As a pilot and IT engineer I am convinced that other reasons are blocking these solutions... I think most aircraft manufacturers do not like systems capable to increase proof of technical malfunctions...
(Boeing AHM systems are not relevant here)

Stone_cold
12th Jan 2015, 10:26
Cruise ship passengers pay hundreds, thousands of dollars for their travels, Apple users pays hundreds for their devices..why is air travel assumed to be sustainable at 10 ringet to travel hundreds of Kms?

boxmover
12th Jan 2015, 14:29
Airline management don't spend money unless the have to. If the law is changed then sat back up will happen if it's not then it will not. Money gets spent on what will save money or help to sell tickets at a good price and not much else.

Wearer sat backup is the best use or money is not in my opinion a forgone conclusion.

PJ2
12th Jan 2015, 17:35
I think it is time to take a step back to examine the need for real-time, full-time data transmission (including CVR data).

In recent accident history, (last 30 years, over which a tremendous reduction in fatal accidents has been the trend, due to CRM techniques, GPWS/EGPWS, TCAS & automation), there has been only one loss-at-sea in which the recorders were not found and which so far remains a mystery and that is MH370 and we don't know if that "loss" was in some way not accidental.

Through great efforts, the flight data recorders of every other transport accident at sea and on land have been found and the causes discerned, and lessons learned. That is a statistically significant success rate. The locating of and the successful retrieval of the recorders from the AF447 is the benchmark against which all subsquent retrievals must be measured. It can be done.

Add to this fact the statistical reality that most aviation accidents occur within an hour of the departure or destination airfield, over land, or over water which is more often than not accessible; QZ8501 is such an example; there are numerous others.

Counterexamples to the above are enroute accidents, (mainly CFIT, LOC, mid-air collision), in which the accident site is in remote territory that is either ice/snow, mountainous or heavy jungle. Yet, to my recollection, there are no accidents, MH370 perhaps excepted, in which the recorders have not been located and retrieved.

The calls for change are understandable but in my opinion are misplaced, sometimes even on the part of those who really do know what they are talking about in terms of the technical solutions to such a proposal.

The data-loss and unsolved-accident rate does not support such solutions.

Not knowing where one's fleet is at any one moment is, however, unacceptable and the many solutions are already at hand and relatively speaking, inexpensive. "SkyTrac" is one...there are many others.

Bergerie1
13th Jan 2015, 14:59
Once again, word of wisdom from PJ2. It would be far better to spend the money on better and more appropriate pilot training as is being discussed by the RAeS, FAA and others.

dClbydalpha
13th Jan 2015, 21:37
Doing some quick calcs based on a couple of educated assumptions
1. For such high data quantities you could get a rate of $1 per Mb currently about $4.
2. Typical data loading of a CVRFDR is about 85 kbps

You get a few interesting results.

Achievable transmission throughput needs to be about 4.5 Gbps to cope with all aircraft, this is a significant increase on the system load, probably meaning that more satellites would be required.

Data charges would be around $3M per hour. Basically a new way of charging for data would need to be negotiated. Or a complete new infrastructure introduced. Either way we are probably talking billions. Money better spent improving primary safety.

Data would have to be stored until it was confirmed that the aircraft had safely arrived at its destination. So a world wide system would need to be defined.


On top of this who owns and manages the data? Airlines? Governments? A global body? A whole new set of regulations would need to be introduced and administered to ensure the integrity and security of the data.

Willie Nelson
13th Jan 2015, 22:53
A few things to consider:

If the weather did in fact play a part in the Air Asia crash, it would be interesting to see if the data transmission would have maintained its reliability throughout, the same could be asked of AF447. Very good satellite reception often collapses during large thunderstorms so I would imagine the same to be true for transmission, perhaps this could be improved.

The legal implications of sending CVR data across satellite communications could be tricky as this data is specifically not stored off site for the benefit of pilots. Should the data be stored off site there is no guarantee that the data would not be used against the tech crew.

There is certainly a case though to, if nothing else, transit a better "last know location" signal to assist in recovery efforts to avoid these massive delays (e.g. AF447 and MH370)

Superpilot
14th Jan 2015, 09:05
If the goal is to implement a solution that can help us locate an aircraft to within a 10-15 mile radius, a very simple solution could be to use the HF radio and have it automatically broadcast a Lat/Long position over some chosen frequency whenever an "emergency" conditon is sensed or when the crew press a "panic" button of some sort. The broadcast can be digital if it can be achieved (don't know to be honest), but even an audible message played continuosly over a frequency which a handful of worldwide stations are tuned into would suffice. Broadcasting and receiving the HF message is free of charge and already included in the subscription and you'd have a very good chance of being heard even a 1,000 miles away (given the right conditions). Minimal technology involved. We'd be doing what the crew would do if they had the time, nothing more required IMHO.

PJ2
14th Jan 2015, 15:02
There have always been two issues in play...one is "where is the aircraft?", and the other is "what were the critical parameters indicating at the time of the disappearance?", (a basic set could be decided upon quite easily).

The first can be addressed (and is being so) with available technology.

The second is a far larger question concerning a concept for data transmission which I think is unnecessary for the reasons given above.

However, there is a way forward if over time it is decided that some "critical path" flight & system data is necessary to at least shorten the time between the disappearance and original causes, if only for humanitarian reasons. This would certainy apply to MH370.

If I understand the basics behind the B787s data recording process, (I am a (retired) pilot and a flight data analyst, not an engineer or statistician!), there are so many parameters that the recording system data capture process "skims the surface" so to speak but when something out of "normal" occurs, the "focus" shifts towards more parameters for affected systems, (and perhaps at greater resolutions and capture rates?).

The notion is, when normal boundaries of controlled flight are exceeded or are in the process of being exceeded, (phase advance process...), the primary recording system bursts data to the deployable recorder in preparation for deployment. If things continue towards pear-shape, the little recorder with a powerful locater transmitter is deployed/parachuted/ballooned etc.

One objection voiced elsewhere is, how to keep such a heavily-reinforced, crash-protected device afloat?

But the whole idea behind such a deploying recorder is that it isn't at the scene of the crash so it can be light, like the aircraft's QAR, and still powerful with today's battery technology, and it can contain gigabytes of data for later examination.

Just protect it sufficiently against normal touchdown 'g' forces and the elements, (water, ice, rocks, jungle, mud, etc).

The alternative is, instead of, or in addition to a deploying recorder, the aircraft's normal recording system sends the several-GB burst of data to the satellite and thence to the dedicated airline, perhaps through the SITA system, or other such position-tracking satellite carrier. Such technology is already in use and available, and though presently expensive, would shift to lower costs as the system gained widespread use.

Wholesale data transmission is far too complex both technically and industrially, (someone brought up pilot concerns with off-site data and believe me, they are very real concerns), it's expense is unwarranted and the capability is unnecessary.

dClbydalpha
14th Jan 2015, 20:59
You're absolutely spot on PJ2. There are systems out there that can and do do exactly that. Trend analysis, exceedence monitoring, etc. deployable memory and burst transmissions.

But let's remember in the case of MH370 it appears many systems were disabled so we can not be sure what would be available.

neville_nobody
15th Jan 2015, 02:05
Millions of Apple clients worldwide, can use Apple cloud backup... but for the safety of airliners, these techniques are too expensive

In which case all the infrastructure to move data around is provided to Apple for free by the governments and/or telecommunications companies. All Apple do is provide the storage device.

If Apple had to build all the infrastructure associated with their cloud there would be no cloud.

AS PJ2 points out the expense involved with this idea is way beyond what is affordable.

Qantas_A380
15th Jan 2015, 06:27
Simple solution for me is to have GPS location broadcast every 30 seconds via an independent satellite transponder that cannot be turned off and has a battery attached to it that can transmit for 10 minutes after power off. That couldn't be too difficult or costly with today's technology.

Pack2
15th Jan 2015, 07:07
There is a system being developed as we speak to transmit FDR data direct from the aircraft in real time..once up and running my guess is that aviation authorities will mandate it for airline operations...

dClbydalpha
15th Jan 2015, 09:35
Ok Pack2 I'm interested.
Well I am if it is the whole infrastructure, can you send me a hint as to where I can find more info please? If it is just the aircraft side, then it doesn't need much development I could have one working this afternoon.
Is the intent for it meet ED112s data requirements? If not then I can't see it being a realistic backup, but it would still be very useful for other purposes.

Unfortunately even with the technology available there are big legal issues over who has access to and responsibility for the data. At the moment it is only necessary to "secure" data after the event and so it is relatively low quantities on stand-alone systems.

Qantas A380 - all systems have to be capable of being disabled for a variety of reasons, it's just a matter of difficulty. The question is where do you want to move the design compromise between normal and abnormal operation. That is a numbers game I don't have the values for, but I agree that flight following data should be reconsidered in the FOSA.

MD83FO
15th Jan 2015, 12:34
Qatar Airways already started testing flight data SAT streaming

Vee1.rotate
15th Jan 2015, 15:02
Dear PJ2,

regarding your first post:
While I don't necessarily disagree with your general position that the cost of the implementation of constant and complete FDR / CVR data transmission might be spent as well on expanded/more intensive pilot training, I would like however, to respectfully point out, that the occasions on which the FDR/CVR could not be retrieved for varying reasons are not as singular as you think or suggest.

There have been several airline aircraft losses (albeit not all of them within your stated 30 year time frame) where the FDR/CVR boxes could not be retrieved or the recorded information was not recoverable.
These aircraft losses have ocurred both over water and land:

Pan Am Flight 708 - crashed on approach to Berlin Tegel airport in 1966,
( FDR/CVR were not returned by soviet union military )

Pan Am Flight 816 - impacted water after take-off from Papeete in 1973
( FDR/CVR believed to have sunken to a depth of 700m )

Korean Airlines Flight 007 - shot down by soviet air force in 1983
( FDR/CVR recovered by soviet union,handed over in the early 90s)

Eastern Air Lines Flight 980 - impacted Mount Illimani,Bolivia in 1985
( FDR/CVR not recovered due to the inaccessibilty of the site where the aircraft impacted the mountain)


These are a few that come to mind and I would not be surprised if there were more.Of course the geopolitical landscape has changed with the end of the cold war,however I would not rule out that another aircraft might be lost over a war zone or a very unstable country where the recovery of the FDR/CVR is not possible for political and/or security reasons.

The same applies to the other reasons, those of site inaccessibilty due to terrain or depth.While I agree that technology has advanced , I still believe there are areas where nature will make it extremely difficult, if not impossible to access (or for that matter, even locate) the FDR/CVR,even with modern technology.

With todays competition in the airline business and the resulting constant cost reduction /minimizing that is taking a high priority within many airlines, I am not too optimistic about the quick implementation of either constant data uplink or more pilot training.
If you ask me,data link is more likely to be introduced in the future than expanded pilot training, which would be a recurring , most likely too expensive ( from the cost cutting department's point of view) cost factor.


Kind regards,

Vee1.rotate

PJ2
15th Jan 2015, 15:37
Pack2;
Not sure what your background is (meaning I don't want to insult your intelligence! ;-) but in re, "There is a system being developed as we speak to transmit FDR data direct from the aircraft in real time..once up and running my guess is that aviation authorities will mandate it for airline operations... "

Such systems are already in place and functional.

I am working with an airline that tracks their aircraft real-time using satellite streaming. It's not an ACMS or ACARS-based system. It is one solution to the regulatory requirement regarding dispatching and flight-following here in Canada; the system not only tracks aircraft from power-up to power-down and displays such information through the web, but is capable of real-time data transmission to the airline or, if the airline chooses to keep costs down, can send data when pre-set parameter thresholds are exceeded. It works no matter where our aircraft are in the world. The capabilities and the possible solutions to present concerns are obvious.

In terms of "events", we can create for example, high-'g' events or flap overspeed events which can be transmitted real-time so that our maintenance people can take action at the next landing. The (Canadian) tracking company we use already have STCs for such installations, not a small investment by any measure.

The point I'm attempting to convey, which is one that any airline exec who knows his or her business will get right away, is that riding off in all directions at once in a knee-jerk reaction to recent events and shrill calls for this and that system is not the way to go about researching serious and complex investments in flight safety systems. I'm supporting the notion that rather than reacting for reacting's sake because the flavour of the day has changed from stalls to finding lost airplanes, a measured, carefully-considered response, which always takes time as does the introduction of regulatory reform, is by far the most expedient and effective way to implement change. The thought-process expressed above provides the foundation for this approach. There is no need to have real-time, full-time data-streaming via satellite for the world's aircraft - that's just a massive waste of limited resources when the very solutions sought are already available and relatively inexpensively at that.

dClydalpha;
Agree on keeping systems capable of being shut down. I was more thinking of the INMARSAT data being sent to RR from MH370, which of course is transparent to the crew and can't be shut down from the cockpit - but such a manufacturer's secure-data system wouldn't interfere with flight or convey proprietary information to non-qualified/authorized users.

Vee1.rotate;
My sincere thanks for your note. I was either unaware of or had forgotten the cited accidents, but was hoping that someone "out there" would be able to supply counter-example information for the discussion.

Certainly, the geo-political comes to mind and also the rapid advancement of electronic and physical search technologies which led to the discovery of AF447's crash site.

In re your comments, "Of course the geopolitical landscape has changed with the end of the cold war,however I would not rule out that another aircraft might be lost over a war zone or a very unstable country where the recovery of the FDR/CVR is not possible for political and/or security reasons.

The same applies to the other reasons, those of site inaccessibilty due to terrain or depth.While I agree that technology has advanced , I still believe there are areas where nature will make it extremely difficult, if not impossible to access (or for that matter, even locate) the FDR/CVR,even with modern technology.

With todays competition in the airline business and the resulting constant cost reduction /minimizing that is taking a high priority within many airlines, I am not too optimistic about the quick implementation of either constant data uplink or more pilot training.", One reason for suggesting the alternative capability, (transmission of data only when certain thresholds are reached), is that I know airlines are incessantly challenged in controlling costs. The decisions made that I am familiar with regarding our own capabilities are certainly governed by these requirements for balance between such capability, costs and revenue generation. That is why I chose to take a "statistical" approach for the discussion. I am making the assumption, (intuited from accidents I knew of, and now added-to by your contribution), that any such "disappearance event" (including war zones), may very well occur at about the same rate for which other engineering probabilities are calculated, that is, 10-9, (bearing in mind the caveat I provided in the second post). Roughly stated, there are going to be such events but, as with all things in aviation, they must be examined for probability as well as possibility and investment of resources decided upon and defended thereby. I'm a flight safety guy so you know where my priorities are.

PJ2

Ian W
15th Jan 2015, 16:10
Ok Pack2 I'm interested.
Well I am if it is the whole infrastructure, can you send me a hint as to where I can find more info please? If it is just the aircraft side, then it doesn't need much development I could have one working this afternoon.
Is the intent for it meet ED112s data requirements? If not then I can't see it being a realistic backup, but it would still be very useful for other purposes.

Unfortunately even with the technology available there are big legal issues over who has access to and responsibility for the data. At the moment it is only necessary to "secure" data after the event and so it is relatively low quantities on stand-alone systems.

Qantas A380 - all systems have to be capable of being disabled for a variety of reasons, it's just a matter of difficulty. The question is where do you want to move the design compromise between normal and abnormal operation. That is a numbers game I don't have the values for, but I agree that flight following data should be reconsidered in the FOSA.

See Qatar pushes for live aircraft data streaming | Avionics content from ATWOnline (http://atwonline.com/avionics/qatar-pushes-live-aircraft-data-streaming) for the announcement from Qatar Airlines.

Iridium Next will support bust data at broadband speeds as will the later versions of INMARSAT. Of course for many events the aircraft may also be LOS to a VDL ground station that would also be able to accept a burst of data. Most ACARS messages are sent over the VHF network rather than SATCOM.

Since the late 1990's there have been several aircraft 'lost without trace' not including MH370, there were 3 aircraft with significant POB with 73 people 'lost'. (if Wikipedia is to be believed List of aerial disappearances - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/List_of_aerial_disappearances) )

Setting up trigger conditions for a burst of data should not be difficult. Ensuring that someone in the cockpit with knowledge cannot interfere with it is more difficult.

Privacy should be simply assured by using layered encryption that requires two decryption keys to decrypt the data with the actual transmission being made to a 'trusted third party' - perhaps IATA, SITA or ARINC. They cannot decrypt it alone, nor can the airline decrypt it alone so bored airline managers cannot look in to see what was being said about them in the cockpit.

Bandwidths are increasing continually beyond the bounds of what was thought possible. It would not be surprising in future for aircraft on startup to connect to a 'cloud' via VDL or SATCOM or both, and stream basic DFDR data continually throughout the flight with full DFDR and CVR data if certain conditions occur. Charging will be per connection not on bandwidth.

Yes the number of DFDR/CVR not fount is very small. However, the costs of all the searches for them is larger than huge - look at the cost of just one day of SAR activity :eek:. I suspect that if Qatar's trial is successful that Allianz (or whoever their insurer is) may offer a significant discount providing some ROI for the airline for equipping their aircraft.