Even though it's consumer-facing, I'm sure they could have reserved a small subset of bandwidth to experiment with realtime flight data.
Hold on while I go patent the shit out of this (yeah right, fuck the USPTO if they approve something so obvious).
What they seem to ignore is that many of these things only work effectively on land in populated areas. Drive your car out to the South China Sea and let me know how well the in-car broadband works and if you are able to send and receive an SMS using your phone.
There was an article on reddit questioning why we can track a rover on Mars but not a commercial airliner on Earth. Our ability to track something is a lot easier when things are going right. When something catastrophic happens, whether to a 777 out over the ocean or a rover on Mars, suddenly tracking the objects becomes a lot more difficult.
That said, perhaps there are technological innovations that could allow us to more easily pinpoint and track black boxes from downed airliners. I'm just not sure what they are. Any ideas?
People don't fully appreciate how difficult it is to find anything in the middle of ocean when there's no visual trace.
Even if you can narrow down the point of impact within a few square miles, you won't know for sure until you get underwater equipment. When you're dealing with deep underwater recovery, all bets are off.
I think low-tech solution would be effective. Perhaps install a few dozen chemically activated florescent devices throughout the plane that would float.
Search parties searched for quite some time, but gave up. Five years later, the plane was found in the woods some 100 meters away from a fairly frequently traveled two-lane road.
Yeah, but our attention spans only last about 12 hours! You expect us to wait that long!?
Though, once the black box is in the ocean with the rest of a plane's wreckage, I can't imagine satellites would help :)
You could lose power, stopping you from transmitting telemetric data. Or there could be a cabin depressurization or breach that cuts off the antennas (or destroys them entirely). I'm not denying there are benefits to streaming telemetric and flight data continuously for non-major mechanical failures and general analysis - but when we're talking about a catastrophic event that brings down a plane?
In such an event you're going to be sending people to look for the wreckage anyway. Whatever data you're streaming isn't going to tell you the whole story - it'll end up looking exactly like the data does today: perfectly normal, and then nothing. I can see that in a 24 hour news cycle people want to know what happened when it happened. It perhaps understandably freaks people out to learn planes can just 'disappear' without explanation. But streaming telemetric data isn't going to help with that, because the only way we can stream such data over oceans (which make up most of the world's surface area) is with satellites, and they're simply not reliable enough for it to be worth anything.
Technology will unlikely replace flight records, which have a proven track record (provided they can be found... but not as many have gone missing as you might think), but it can certainly augment it. I still don't think it's as good a solution to the "real time" problem as having the recorder on board the accident aircraft itself.
Edit: Sibling comment from objclxt incidentally is the same user who illustrated the problems with satellite communications I alluded to. See objclxt's comment history for details.
http://en.wikipedia.org/wiki/Iridium_satellite_constellation
Beam up some coordinates every minute from an Iridium phone strapped to the roof. Pair it to an iPad to get those coordinates.
Maybe have a second phone/ipad strapped onto the underside too just in case the plane ends up flying upside down.
Wifi and cell-phone have speed limitations (receiver transmitter), also, they are not adequate for something flying 500knots at 35kfeet
However, it is true that systems could be upgraded and offer a bigger bandwidth (within a certain limit)
We have billions of dollars of equipment focused on tracking that rover, and we still lose contact with it sometimes.
http://www.independent.co.uk/news/business/news/airbus-engin...
http://atwonline.com/engines/final-qantas-a380-engine-failur...
http://www.rolls-royce.com/about/technology/systems_tech/mon...
Apparently 2-3 kilometers according to [1], which I found in the comments from here [2].
[1] http://www.hydro-international.com/issues/articles/id1098-Ai...
[2] http://www.aticourses.com/blog/index.php/tag/side-scan-sonar...
> A recent patent application filed by Boeing describes such a system, which specifies a limited data set including the precise location of the aircraft and the flight control inputs by the pilot or the automation system.
Clearly, Boeing themselves are thinking towards continuous tracking of a flight.
We can track any commercial airliner on earth, but not under 5 Km of water.
"Your iPhone is more powerful than the evidence-collecting computers in the cockpit. Simple changes could mean faster answers for plane crashes"
You're talking about the black box for a airline jet. This thing is supposed to survive plane crashes; not just being dropped a meter off the floor, but smashing into the ground going 100's of meters per second. The design constraints in those conditions include, assuming the plane is now a ballistic fire ball smashing into the ocean: operating temperature well above even industrial components to survive the fire, mechanical strength to withstand hundreds if not thousands of g's during impact (at this speed the ocean is the same as solid rock), and then float in the freezing ocean for days if not weeks until it is recovered. I'm not sure if black boxes are guaranteed to float or not, but if they are designed to sink, they must then withstand tens of atmospheres extra pressure for a sustained period of time.
The secret is that smartphone processors have been more powerful than safety critical processors since their inception with the IBM Simon [1]. The RAD750 [2], NASA's only "current generation" processor, began to fly in 2005 with a whopping single core with a 110Mhz core clock and an older manufacturing process than that of processors used for early 2000's era smart phones. When technology is moving so fast that Intel is building a new multi-billion dollar factory every few years, safety critical device designers don't give a shit about how fast they are. They care that they can get a level of confidence in the stability and reliability of the processor, that it has years of data on life time, and then that it can be manufactured by an array of suppliers. That cannot be guaranteed by cutting edge technology, no matter how many bits or fancy virtualization features you throw at it. For the black box, this means every component in the design must survive and operate (an IC can survive the hundreds of deg C in a reflow oven but it sure as hell won't work if you send current through it) at or close to those conditions.
A flight data recorder is one of the worlds most indestructible pieces of technology, whose main function still works having been smashed into the land, undergone a fireball, or dropped to the bottom of the sea.
An iPhone breaks when you drop it from three feet and becomes little more than an expensive piece of junk (as do all modern, touchscreen smartphones).
Good luck getting a satellite or cell signal a few fathoms under the sea, near no cell towers.
None of this solves the issue of sorting out what happened during a catastrophic failure. It's likely any transmission based system will fail is such situations. The only reliable way to have real time information is to use external sources, e.g. high resolution radar covering every point on Earth, that isn't cheap nor politically easy.
But as I understand in this situation they were not out of ADS-B range nor were they out of radar range. While ADS-B requires the aircraft to transmit, radar does not.
An example of an in-flight breakup happened in 2002 when China Airlines 611 which broke into 4 pieces about 40km off of an island. Looking at the radar returns they found the aircraft broke into 4 large chunks and they were able to tell where items would be due to the radar tracks.
I'm really not sure what's happened here but my hunch is that the incident happened at the boundary of one or more countries' radar systems. So Malaysia needs Vietnam and/or Thailand and/or Cambodia and/or China to turn over their radar returns so that everything can be lined up correctly.
If it was all within one radar system you would have a location pinpointed within an hour.
Bandwidth: quick googling shows that a flight data recorder records between 64 and 256 12-bit words a second, i.e. 1-3 kbps. Browsing http://en.wikipedia.org/wiki/Bit_rate shows that another 2-8 kbps is needed for voice recording (from one microphone). Let's call it 10 kpbs all together.
Number of simultaneous connections: there are around 20,000 (ballpark) airliners in the air at the peak time each day.
Compare this to the rather old Iridium satellite network: 2400 (uplink) baud rate, 1100 calls simultaneously per satellite (of which there are 68). Not quite enough, since airplanes are not evenly distributed over the Earth or under the satellites, but not outrageously far from our requirements.
Cost: several billion dollars (under 10, I think) have been invested into building the Iridium network, and their operating expenses are around 100 million per year (they are a public company).
Clearly, it would not be unrealistically expensive, in the world of 500 million dollar airliners, to build and maintain a network of satellites to record all black-box voice and data in real time.
I am not sure what you are trying to say.
The blackbox is like your log file on a server: the flight recorders (flight data recorder and cockpit voice recorder) in aircraft, (wiki). So if you want to know what happened to the aircraft, whether after a fatal crash or after a hijack or after emergency landing, the blackbox is ultimately the best source. Don't forget there is a legal responsibility.
It is totally rational.
What are your thoughts on the rather knee-jerk articles as of late that seem to think that some form of streaming technology is somehow absolutely imperative, and how might that compare to the tried-and-tested flight recorders given what we know from AF447 sharing periodic updates as to its status?
I do find the aviation industry to be sometimes peculiarly behind the times. For example, a few years ago, I wondered online why airports did not have constant video recording of the runway and taxiways. Such would have been enormously helpful in solving many accidents, such as the SST crash.
But an airline pilot argued with me, saying that such would be cost prohibitive and thoroughly impractical. I was baffled by such statements, given that every 7-11 had constant video surveillance.
I do follow air crashes and the subsequent investigations, the engineer in me just cannot resist. The investigations are so thorough these days that it's pretty rare that the cause and chain of events are not thoroughly understood. The only issue is sometimes it takes years, which can get pretty frustrating for people (including me) who like instant answers. The mitigating factor is accidents are now extremely rare. I don't think that the cost of a live streaming system is clearly worth it.
The black box system has turned out to be probably the biggest single factor in improving safety ever devised. They work great, and the aviation industry is (naturally) very conservative about changing things that work.
ironically part of my master thesis is about blackboxes and satellites. iridium has been working with some company about the topic(i think, i wish i remembered the details, but you can just google them). but generally iridium is slow right now(that might change but when i say slow i mean less than 4kbit slow), and i think the main reason why it's still there is because it covers the poles.
rolls royce actually already deployed a thing that transfers data through satellites, so you can actually get live engine data. this is almost ironic since their engines seem to be so crappy that a significant portion of them requires replacement according to qantas.
inmarsat on the other hand is much faster. you have to consider though, in a lot of regions you have way more planes than you have bandwidth. also inmarsat is already heavily used by ships(which from what i heard have a lot of virus infested windows pc's sending bogus junk). there is no way
the main issue is that we can easily have way more planes than we have bandwidth per spot beam
[] http://www.bea.aero/en/enquetes/flight.af.447/flight.data.re...
[] http://www.telegraph.co.uk/finance/newsbysector/transport/10...
[] http://www.rolls-royce.com/about/technology/systems_tech/mon...
How many planes go down each year? A few. How many planes are never found (black boxes). One per 10-15 years?
An airline, or a company that builds planes would have little to none problem explaining to the judge that benefit-cost analyse make no sense: too much money would be spent for too little benefit (I know lives may be at stake, but that won't convince the judge).
Couple years ago I read an interesting article about the way Boeing builds their wings and the way petrol compartments are organized inside such a wing. It went on to explain that in particular external conditions of air, at particular speeds, with particular climbing angle and with particular temperature of aircraft coat, there is a chance of petrol ignition. The only "problem" is that according to their calculation, the probability of all conditions being right is 1:17,000,000. While re-engineering the wing and then applying changes to each aircraft would go north of a billion dollars. Therefore, they have not upgraded their aircrafts and no authority went after them surely because of tiny chance of an accident occurring.
We are all flying a ticking time bomb to some extent. The chances of something going wrong are comparable to putting a parrot before your keyboard. How much time will it take a parrot to hit a combination of keys writing "parrot". It may be one billion years! Or five minutes...
What lives are at stake? An enhanced black box won't prevent accidents, and, with very few exceptions, it won't help us find out the cause of accidents. I think your take on the "cost-benefit" analysis made the most sense.
Your 1 in 17 million scenario is interesting - how many times per flight is that scenario evaluated, or is that per flight? If per flight, and suppose we have about 20,000 Boeing flights a day, then we would have a Boeing explosion every 3 years. (Adjust the numbers based on how many Boeing flights there are) - I would say it's worthwhile making the change there.
My iPhone 5s is arguably "more powerful" than the Hasselblad 501cm[1] I currently have sitting next to me. The iPhone has a built-in light meter, flash, and GPS. It can take more than 12 photos without reloading.
But, the Hasselblad was designed to satisfy a different set of criteria than the iPhone. And, for those criteria, it's absolutely perfect. If I want to Instagram something I'll use my iPhone[2]. If I want to shoot a photo I can print at sizes measured in feet, I'll use my Hasselblad.
Is it possible that the airplane black box needs a 21st century rethink? Sure. But to dismiss it in the article subhead does a disservice to everyone who reads the article.
[1] not my blog and not my photos, but representative of the camera: http://blog.mingthein.com/2013/07/27/fd-shooting-with-the-le...
[2] Actually, I'm one of those people who only uploads photos taken with a 'real' camera to Instagram, but you get the idea.
Here's Wikipedia on the subject (http://en.wikipedia.org/wiki/Air_France_Flight_447#Automated...):
An Air France spokesperson stated on 3 June that "the aircraft sent a series of electronic messages over a three-minute period, which represented about a minute of information. "[32][33][Note 2] These messages, sent from an onboard monitoring system via the Aircraft Communication Addressing and Reporting System (ACARS), were made public on 4 June 2009.[34] The transcripts indicate that between 02:10 UTC and 02:14 UTC, 6 failure reports (FLR) and 19 warnings (WRN) were transmitted.[35] The messages resulted from equipment failure data, captured by a built-in system for testing and reporting, and cockpit warnings also posted to ACARS.[36] The failures and warnings in the 4 minutes of transmission concerned navigation, auto-flight, flight controls and cabin air-conditioning (codes beginning with 34, 22, 27 and 21, respectively).[37]
...but also not very useful. Two minutes is a long time when you're traveling at 570 MPH - in the event of a catastrophic explosion a plane could be on a perfectly normal flight path one minute and then gone the next, and you still have a vast radius to cover when looking for the wreckage.
Given how much these planes cost it does seem reasonable to have real time telemetry. Yes it is hard. Yes it is expensive. But no where do I read it can't be done. In fact I think a lot of technological innovation has been driven by people saying "Nope...you can't do that.".
Where is the incentive to provide real time telemetry? More crashes? This is one place where I feel the FAA does have quite a bit of responsibility.
As to the first objection, any catastrophe would be preceded by the cause of the catastrophe. This is what one would hope to capture. I'm not sure if that covers every possible case but I it could be of great value to have instant access to events just prior. As to the second objection, intelligent systems can make useful decisions about which data to transmit and about how long a burst of information should be sent.
Anything that can be done to reduce the time needed to locate passengers who are injured or trying to survive on the ocean or in difficult conditions deserves a look, in my opinon.
Why is it a significantly larger value than having access at worst two years later? No plane went down due to the same problem while they were looking for the AF 447 black box.
> Anything that can be done to reduce the time needed to locate passengers who are injured or trying to survive on the ocean or in difficult conditions deserves a look, in my opinon.
Passengers might survive reasonably successful ditchings, after which currently-fitted ELTs activate and transmit location as you expect. An event that results in ELTs not activating is generally not survivable in the first place.
An alternative would be to eject the DFIRS when subjected to high acceleration like an Airbag in a car. In a large proportion of crashes, the nose of the jet hits first.
There is already a perfectly capable technology in place: the 406 MHz ELT. If it turns out the the (probably two) ELTs did not transmit, we need to think about why.
Things can go bad quickly on a commercial jet. No one has time to manually activate the ELT before a sudden impact.
At least one of the ELTs is required to activate automatically in case of an impact. A hard landing is enough.
So why did at least one of the ELTs not activate? here are some possibilities:
1) It did, and we don't know about it. The media is so ignorant about the details of technological systems that they don't know the questions to ask, cannot understand the relevance of technical details, and would not understand the answers in any case. Welcome to the idiocracy.
2) An ELT activated, but was not picked up. Very unlikely. If an ELT activated aboard MH370, the satellites would almost certainly have received the signal and passed it on.
3) The aircraft hit the water intact, and the ELTs were destroyed before they could activate.
We can't do anything about the stupidity of the media except to educate ourselves, stop consuming media garbage, and hope that, eventually, the human condition will improve.
If option (3) is correct, then we can also do nothing. Any force sufficient to interfere with the safe operation of the aircraft by competent pilots should also have been sufficient to activate an ELT.
If the ELT did not activate, it means that the aircraft was flyable. We cannot adjust the sensitivity of the ELTs to activate on flyable aircraft, because the rate of false activations would be unacceptable.
Apparently, we also cannot eliminate the impact of flyable aircraft with terrain by pilot training; quite the contrary--the phenomenon seems to be increasing.
Improved autopilots are also not the answer. Of necessity, an autopilot must relinquish control to human pilots in many circumstances where anomalous data is received. This is the circumstance in which it is most likely that the human pilot, taking control of a partially disabled aircraft, often at night and over water, will crash a flyable aircraft into terrain. There has been a growing series of such accidents.
So, no, we do not need to rethink "black boxes". They do their job very well. We also do not need to rethink the ELT--it is a very reliable technology except when people crash a flyable aircraft.
We may want to continue to upgrade the packet data rate between the aircraft and its base, but that is already the plan.
We also cannot upgrade the autopilot, because we cannot yet create artificial intelligence that can deal with a chaotic system like a partially disabled aircraft.
We may want to think about giving pilots better ways of seeing an overview of their situation. Mandatory AOA indicators and external-view situation indicators would be a great start.
Probably also rethinking reflexive media coverage of aviation would be good. Our need to know immediately does not trump the well-thought-out engineering of commercial airliners, and pandering to our self-absorbed search for meaning and quick fixes, particularly when none is available, is likely degrade, rather than improve, the human condition.
In the case of the Air France crash, telemetry data was sent out in the good 15 minutes it took to go down. With this flight - nothing. One moment it was sending data saying all was well, the next it simply disappeared from the screens. Extremely unusual. If there was a sudden disintegration of the aircraft, there's a good chance an internet-based device would go offline too.
I believe the black box has a signal that will let it be found but it only has a range of 1-2km - less underwater.
What is perhaps more boggling is that you just need a last seen GPS coordinate or set to help find the boxes and the plane - a GPS packet if you might call it. Similar emergency transmitters are already available for yachts and boats.
The mystery of MH370 may uncover a number of simultaneous problems or deficiencies of procedure.
* There often aren't many big pieces left after a breakup at 550 MPH.
* The debris is falling 7 miles, so where it actually lands is pretty random and dependent on the shape / weight of the debris. Lower density debris probably travels further.
* Most debris sinks when it does get to the ocean.
* The lower density debris that floats moves in currents.
* You can't search at night, so the floating debris might move considerably before you can start searching.
Or rationally, don't change a damn thing. Airliners are fine. Any other form of transportation (maybe with the exception of trains) is many times more deadly and we cope with that risk just fine.
Not really. The hard part is knowing when to use such a system. In most of the catastrophic crashes I've heard about no one knew they were in danger till they were dead.
> to satisfy the bloodlust of news corps
That's not what it's for, that's horrible thinking. It's for determining what happened so we can prevent it from happening again!
> Any other form of transportation (maybe with the exception of trains) is many times more deadly and we cope with that risk just fine.
Because of those same data recorders you denigrate! And now that we've reached a plateau of sorts, it's time to move to the next level.
Ejection Seats are deadly/extremely dangerous if the person in them is not properly trained. Body position when the seat fires can make the difference between minor scratches and death.
But… COULD it have been diaabled? Why have no “pings” been picked up as yet?
We should instead supplement our sturdy but silent black boxes with a chattier partner. The new device would not survive a catastrophic breakup. Nor would it receive the omniscient breadth of data trusted to a black box. Instead, it would (1) receive a subset of flight data (e.g. location, alerts, and pilot inputs) and (2) immediately send them to a ground-based datacentre. These data would back up air traffic controllers' radars in real time. They would also assist in locating fallen planes and their more comprehensive black boxes.
It seems to me you've described ADS-B[0], which this plane had and which will become a requirement in US and EU soon. Looking at sites like flightradar24.com, which use ADS-B data, it would seem most airliners already use it. The only difference from your requirements is that ADS-B doesn't broadcast any information about pilot inputs.
According to records from one of the sites which use ADS-B, the signal from this plane just stopped [1]. This could have happened because of a severe failure in flight, or maybe because the plane descended below cruising altitude which happened to take it out of receiver range. In either case, it shows that the proposed scheme would be of limited use and it might not have helped in this particular case.
[0] http://en.wikipedia.org/wiki/Automatic_dependent_surveillanc...
[1] I'll search for the source when I get back to my computer. It was discussed in /r/aviation.
Just so everybody understands, here are the specs advertised by Honeywell Aerospace for the type of box on e.g. AF447 (the Air France flight which crashed in 2009):
Advanced Recorder (AR):
available as
Cockpit Voice Recorder only (AR-CVR)
Flight Data Recorder only (AR-FDR)
Combined Digital Voice and Data Recorder (AR-DVDR)
- Underwater Locator Beacon (ULB).
- voice recording duration: 30, 60, 120 minutes.
- data recording: 10, 25 hours.
- Height – 6.1 inch; Width – 4.8 inch; Length – 9.49 inch;
- weight: 8.8 pounds.
- designed for data recovery even if subjected to
* Impact Shock – 3400 G, 6.5 milliseconds
* Penetration Resistance – 500 lb weight drop from 10 feet
* Static Crush – 5000 lbs, 5 minutes
* High Temperature Fire – 1100°C, 60 minutes
* Low Temperature Fire: 260°C, 10 hours
* Deep Sea Pressure and Sea Water/Fluids Immersion: 20,000 feet, 30 daysI'm not disputing anything you wrote above, but right now all our eggs are in two very expensive baskets (FDR/CVR). When a plane goes mssing you want to pinpoint the location of the crash ASAP and get some telemetry as a second priority. The existing systems are great but could we not also benefit from some cheaper and simpler systems that didn't rely on being bulletproof?
So you've replaced a single point of failure (failure of the recording device) with 4: failure of the ejection trigger, failure of the ejection mechanism, failure of the parachute, and failure of the (significantly weaker) recording device.
The point of a black box is that it's an when all else has failed device - there are extremely few assumptions you can make about such a situation, so the correct move is to design as conservatively as possible. The plane could be gliding. It could be a raging fireball. It could be missing a wing. It could be about to crash but all the sensors still think everything is just great.
Older processors constructed on older large-size processes and often operating at higher voltages and slower clocks are more robust because they have a smaller number of transistors, which means a simpler more predictable model of error propagation; larger features mean lower current densities, increasing resistance to electromigration and decreasing the chances of defects from natural process variation; higher supply voltages reduce the effects of noise; slower clock rates allow more time for noise-induced glitches to settle instead of propagating.
One of my favourite examples of this is the CDP1802 - an 8-bit CPU from the mid 70s, which is still in production and use today in aerospace applications.
With regards to why video recording FDRs aren't in place, look no further than the FAA [1]. The original request from the National Transportation Safety Board (in pdf) from 2000 is also available [2] although I'm sure the issue has come up since then. However, the FAA doesn't govern Malaysian aircraft except when they fly to the US (I'm guessing 777s were up to code though)
[1] http://www.ntsb.gov/safetyrecs/private/history.aspx?rec=A-00...
[2] http://www.ntsb.gov/doclib/recletters/2000/A00_30_31.pdf
Blackboxes are equipped with a sonic and radio location beacon. Because of the remote locations they have to work in battery life is measured in days and hours since they have to send out a fairly powerful signal using the weakest antenna configuration.
GPS is out of the question for the moment. It requires a power hungry DSP and signal amplifier. Even now, most smart phones use the GPS occasionally then supplement that information with the accelerometer (ie, dead reckoning for smartphones).
No he's not. He's talking about the "evidence-collecting computers in the cockpit" that send the data to the black box.
No, he's saying that collecting the black box is a pain in the ass so there should be a permanent data link to ground.
Plus his whole premise is wrong, as there already is one: http://en.wikipedia.org/wiki/Aircraft_Communications_Address... there just isn't enough bandwidth to send much more than basic systems failure data. Certainly not enough to send the kind of information stored in the black box, and not until the final moments of the plane either.
http://en.wikipedia.org/wiki/TWA_Flight_800
http://en.wikipedia.org/wiki/China_Airlines_Flight_611
http://en.wikipedia.org/wiki/Air_France_Flight_447
Of the three, TWA flight 800 is the only one whose cause is controversial, and in-flight data transmission likely would not have helped identify the cause of that crash.
Of all the above accidents, the causes are understood and have not been repeated. In fact, the cause of Air France 447's instrumentation failure was understood before the crash - there was an an active airworthiness directive to fix the pitot icing.
Extraordinary expense with no(?) payback.
It looks like ACARS already uses Iridium http://en.wikipedia.org/wiki/Aircraft_Communication_Addressi...
You might be able to lower costs by tolerating increased latency and using higher orbits. You'd still need something for pole coverage, of course.
Granted, aircraft fly high in the air, but there are no line-of-sight problems as with terrestrial radio links, so even high frequency comms are possible.
At 40,000 ft altitude the horizon is still only ~240 miles, which will still give LOS problems for VHF and above, particularly in bad weather.
Most crashes are due to human error or complex system problems that often include already known issues rather than a single thing failing catastrophically. Airbus put out a maintenance bulletin about pitot tubes freezing before AF 447 crash, and cockpit/crew management, concentration and problem solving while startled, and computer mode confusion were all known. The most recent example of one solid hardware problem are the 787 batteries and thanks to QA systems we know they are problematic but, fingers crossed, so far they haven't gotten bad enough to kill people. If a 787 goes down you know this will be the first thing looked at even without instant access to logs.
A new airplane entering production with a flaw that will go unnoticed until it suddenly starts crashing planes en masse is just incredibly unlikely. On balance of probabilities, we're better off focusing on existing known problems rather than coming up with super high tech monitoring schemes.
They don't need to send it continuously, so I wonder why it is only hours. Sending a loud short ping once an hour shouldn't consume too much energy. Of course, I don't know enough about radio physics to know if it'd be enough, say, if it is 1km underwater - that may be a problem. Maybe supplement it with acoustic ping too?
GPS is not needed continuously too - it can record last reading, say, before high-g acceleration event and then let the GPS unit be destroyed, burned, starved of power or whatever happens to it. I.e. continuous GPS is needed only when everything is OK and the device is connected to the plane's powerplant - once it is disconnected, record last known GPS and shut down everything - we're in trouble, so the only task for it now is to scream loudly until it is found.
I mean, here we are after 3 days and none of the surface vessels can find the possibly-debris stuff seen from the air earlier today. I don't have a design for a foolproof system and am under no illusions that the existing 'black boxes' could be easily replaced, but the existence of commodity-cheap sensors, processing, and communications technology mean we can afford massive redundancy.
The existing black box is not a single point of failure. The big question is finding it ... that's what this whole concern has been over (and, since you missed it, why I joshingly call you dense).
Anig also clearly stated that there would be 20 of these, operating in parallel. Your math is wrong because you ignore his central argument.
A large airliner would be easier to find on land though - just look for the glow.
Believe it or not until 1973! there were massive land-based lighthouses all across the United States that would illuminate the aerial pathways that aircraft would use to get across the United States.
Doesn't the technology exist to detect low power signals from a much greater distance? The US military must be able to do it?
If for nothing else than to rule out some areas / possible outcomes... But yeah, very far out of my realm of expertise, though I do hope to finish my PPL fairly soon & am an avid AVHerald & LiveATC follower! :-)
The pingers are sonar (well, sonic, but detected with sonar), with all the limitations that implies.
In fact, I was just thinking about how you could probably put a miniature blackbox in every single airline seat. Airline seats are already designed to float, and you'd only need one of them to be recoverable. Such a black box might not be capable of storing everything traditional black boxes do, but if it managed to capture a last moment GPS position it might make it much easier to find the regular black box.
I think that's a distinction without difference. At 500mph, the water might as well be rock.
TRW makes them as well, but couldn't find data sheets on theirs.
You might also find this relevant. http://www.ntsb.gov/doclib/manuals/FDR_Handbook.pdf
But even if we assume that there really isn't a meaningful difference in the physics of a ground vs. water impact, I think there still might be an advantage to having your conventional black box optimized for maximum survivability and having an auxiliary black box which sacrifices some degree of survivability at the extremes in exchange for improved discoverability after an accident.
Wow.
To be clear though: I was talking commercial operations which generally operate above the radar plane. I'm not even sure how/if Fosset's plane would appear on radar as he had no ADS and he didn't file a flight plan which means he was in class G or possibly E airspace on a VFR mission (very low altitude).
He also says that there should be a permanent data link to ground. At which point you say (paraphrased), "there is one, except there isn't".
No, he's mentioning them. He's not talking about them. You could know by having read the article and noted he says nothing about them outside of the subtitle.
> At which point you say (paraphrased), "there is one, except there isn't".
The actual paraphrase would be "there is one except physics". There is a link, it can't magick reliability which does not exist when the computer is a flaming ball of debris in a storm. His proposition boils down to "magick up a reliable connection and send a subset of the blackbox data over it" (note the part where changing anything to "evidence-collecting computers" figures nowhere in the proposal?)
Yes he is, in the part I quoted. That's the part I'm talking about, which is why it's the part I quoted. Learn what the word "context" means. It's the part that the comment I was replying to quoted. Try and keep up.
> The actual paraphrase would be "there is one except physics".
Use the existing wifi connection to send additional information that at least would give you the location of the plane to the nearest kilometer. There are no laws of physics that prevent this.
Or connect via another aircraft who is further behind them but on a similar flight plan.
Here is probably one of the worst flight paths for this type of potential comms http://flightaware.com/live/flight/UAL888/history/20140310/0...
I had intended to use that to support my notion that aircraft tend to stay near land. I've flown that route several times and each time we flew an arc that kept us near or overland. Like this, but never in Russian airspace. http://flightaware.com/live/flight/CCA985/history/20140309/0...
Man, these guys are all over the place. I may have to reform my ideas about flight paths.
A significant number spend lots of time more than 200 miles from land. And "land" here means some land with a data link endpoint.
With respect to airplanes forming some sort of mesh network, consider the bandwidth requirements throughout this link.
Right, but all that is really necessary is groundspeed, altitude, and equipment number. That gets you enough information to find a crash / forced landing site quickly, and to know where to search for wreckage. So, even for those parts of the flight path that are "dark" It still may be potentially superior to low-bandwidth satellite links.
No, he's not talking about these systems.
> Use the existing wifi connection
The fuck are you talking about, planes don't have wifi connections. Do you think they've got a a wifi antenna outside connecting to an AP on land?
> to send additional information that at least would give you the location of the plane to the nearest kilometer.
That already trivially fits in the ACARS, and is completely useless since it's available from radars in the first place, until radar and data links become unavailable.
Yes they do. I'm talking about the connection that is used to provide wifi to passengers on the plane. It's a satellite connection.
If the location is available, how did they lose the plane?
I think this hits an important point that's lost in the media scuffle that inevitably ensues.
Because modern travel has made the world so much smaller, most people have a difficult time trying to fathom precisely how vast the oceans are and that we base our notion of coverage on what familiarities surround us--that is to say: land.
There are certainly cases where the telemetry link would fail as the aircraft ran into trouble, rendering it useless, but there are undeniably cases where it could save hundreds of lives
The Boeing (and I'm sure others) design philosophy is "unsynchronized joysticks ARE A TERRIBLE IDEA", and if Airbus and Air France had use the normal synchronized yokes, the problem of the brain wedged junior pilot would have been quickly apparent.
Can you think of other examples?
BTW, it's guessed that iced up pitot tubes caused the autopilot to disengage.
You're also assuming the pilots would listen to a kibitzer from afar while struggling to fix their plane. Plus a hell of a lot of expensive technology to support all that. And expensive kibitzers looking over the pilot's shoulders, which the latter wouldn't like.
I'm aware that the pitot tubes iced over, but they de-iced long before the point of no return
And I bet the pilots would have listened to a 'kibitzer'. The senior pilot actually told the junior one to stop pulling up, knowing it would cause problems, and would presumably have taken control more forcefully if he'd been aware that the junior pilot had resumed pulling up after bein asked to stop. He just didn't know. Better communication, syncd joysticks or telemetry could all have helped make him aware of that.
There were many problems with the plane, including the physical one of the pitot tubes freezing up (despite heating elements installed to prevent that), and the software and design problems relating to silent disengagement of parts of the auto-pilot, silent transfer to different flight modalities by the auto-pilot, and poor affordances in the physical user interface itself.
Certainly the subsequent pilot error did not help, as the flight would have been recoverable if proper action had been taken, but it wasn't just the pilots either.
Either way if you think some random shore sider would have been able to identify the exact pilot fault and clue them in within time parameters even with the inherent latency of satellite comms you more faith than I do.
Not many, a single problem actually. Plus, the plane was not crashing after the issue occurred and the autopilot was off. The crew misinterpreted the signals and did not pay attention the Stall alarms repeatedly. The plane was flying fine even without the autopilot, it's a case where the crew actually crashed the plane by themselves.
b) Even if there was telemetry that sent the aircraft control inputs and instrumentation to the ground, with thousands of aircraft in the air, nobody would have been watching AF447's telemetry, waiting for Something Bad to happen.
c) It was about four minutes between when the aircraft got in trouble and when it impacted the ocean. Even if the aircraft declared an emergency and someone was able to pull up the telemetry for that flight, it is highly unlikely they would have been able to identify the cause before the aircraft impacted.
It would also be quite simple to be running a bunch of automated tests on the telemetry from every plane in the sky and flagging anything out of spec. AF447 fell into the ocean. It's pretty fucking simple for a computer to monitor the altitude of a plane and say "one of your planes has significantly deviated from it's target altitude".
And "highly unlikely they would have been able to identify the cause" seems highly unlikely. The plane was stalled, and somebody was pulling up as much as possible. Is it really hard to imagine a pilot on the ground being unable to spot what was going on?
Even the captain on board figured it out quickly once he was summoned - the problem was flagging the issue/asking for help was done solely at the pilots discretion and they chose not to tell any body what was going on until it was too late
There are something like 10k commercial flights in the air at a given time around the world. How would that somebody on the ground know to look at that particular plane's telemetry?
I wonder if Google's Project Loon [1] would be of any use here.
Duplex doesn't fix no propagation.
Look at what happened in flight AF447. Everything occurred in a matter of minutes. Even if what you mentioned were to be in place, there would be virtually no time for an operator to do anything about it. And probably such operators would have to go through textbook questions because such regulations would be imposed on them by the FAA.
That's why we have several pilots in every aircraft, to mitigate the risk of human failure. Having more operators outside of the plane are not going to help much. If you want to put more engineering power, it's more software in the plane that is the right way to go for safety, as demonstrated so many times before.
Look, read the AF447 case again and the reports of what happened in the cockpit! The pilots were not EVEN listening to the different alarms being triggered in the cockpit and did not realize that they were in danger no matter how many instruments they had indicating major issues in front of them. In such situations what would make you think they would give a shit at what an automated message coming from a land operation would tell them ?
Sometimes a fresh opinion, or some input from somebody who is removed from the situation, is all that you need to set you on the right track or break an assumption that you were incorrectly holding.
I'm no expert in HF, but my general understanding is that while auto band-hopping could be helpful, you are never guaranteed there is a usable band.
Keep in mind that over-the-horizon radio communication is subject to the vagaries of the ionosphere and is not totally reliable.
Non-line-of-sight radio communications are short wave (well, also medium wave and long wave, but those modes require significant power). If ionospheric conditions are bad, as they are at many times of day (worse at night for some bands), at many times during the sunspot cycle, and during a solar storm, and sometimes during atmospheric events, then you won't get a radio signal through. One famous example of this was just prior to the Pearl Harbor attack, communications via radio between US and Hawaii were very poor or nonexistent for key parts of the time.
So to put a number to your question "likely better than half the time".
I'm not sure how you get from 'because communications between arbitrary point A and and arbitrary point B are sometimes impossible on band C' that "likely better than half the time" communication will be impossible on every useful band to any useful place.