Inside FAA's GPS-Based Air Traffic Control 290
longacre writes "With the growing number of planes in the air setting its archaic radar-based air traffic control on a course toward 'total system collapse,' the FAA has quietly begun testing a new GPS-based system on Alaska Airlines 737s. While radar can take over half a minute to determine a plane's location, GPS technology known as ADS-B broadcasts an aircraft's position to controllers and nearby pilots essentially in real time. If all goes as planned, travelers will see fewer delays as planes will be able to fly closer together and in reduced visibility conditions, and airlines will achieve significant fuel savings by flying more direct routes. The feds plan a gradual rollout over the next two decades that may cost up to $40 billion." There's still some contention about where the funding will come from.
Just tell the troops... (Score:3, Insightful)
$40 billion? (Score:5, Funny)
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Man I sure want a garmin and a cell phone handling 11 airports worth of airtraffic. Replacing the infrastructure for all the TRACONs/Towers/etc across the States is why it's going to be expensive.
Dangerous! (Score:4, Insightful)
If you trust the planes to tell you where they are, there is a potential that the planes could lie to you. I really hope they take that into account when designing the system.
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I think that they already rely on the planes to transmit a lot of data correctly.
To the best of my understanding, civilian flight-control RADAR isn't an "active" system. It doesn't put out a whole lot of power and look for reflections, like a military system does. It's just a receive-only system, which listens to the signals being tran
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The system has to be extremely reliable and fault proof, so that means the development costs
Re:$40 billion? (Score:4, Insightful)
For a time every single plane in the sky will have to have the ability to use both systems at once... and each air traffic control tower will have to be able to control both systems at once... and then you need to train the pilots and air traffic controllers to use the damn thing (you may think it is easy, but I don't feel like "on the job training" is too great of an idea at 50k feet)
Then you need to have a system that can interface with the hundreds of different models of planes...
And it needs to have 99.999% uptime (with a few more 9s in for good measure)
And don't forget, you are going to need to have some agency with some big staff to organize this entire thing... and that office is going to need a secretary, and a few lawyers, etc, etc, etc... (even if you think it is a waste, there needs to be some people SOMEWHERE handling all of this, and they are going to need a copier, some toner, and perhaps a
Re:$40 billion? (Score:5, Interesting)
Its not easy, but I can't see the infrastructure component of the system being more than a billion USD. That leaves you 39 GUSD to equip you entire aircraft fleet with mode S transponders. It sounds like an excessive price to me.
The big challenge for the ATC system becomes scalability. Current methods of detecting aircraft are:
The primary radars might have a maximum range of 100 NM. The secondary radars about 250 NM. ADS-C works anywhere you have satellite communication but in practice only airliners in remote airspace will be using it.
ADS-B gives you almost 100% coverage in your airspace. Many more aircraft are detected.
Putting an ADSB transponder in every aircraft in the sky (ultimately) means that the ATC system has to start dealing with many times more aircraft. At the very least you need better filtering to enable the controller to see the aircraft he has to control and not be distracted by uncontrolled aircraft nearby.
IMHO the torrent of new information will eventually lead to ATC systems delegating their tactical control to automated systems. Any other approach ignores the potential of this technology.
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Despite the somewhat high cost of the avionics, the real expense is the ground stations and the infrastructure to process all the data.
Funding... (Score:5, Interesting)
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Re:Funding... (Score:5, Insightful)
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The long story is that, although the airlines probably did deserve some compensation for business lost over 9/11, like every other good-intentioned policy this administration has implemented, it got completely FUBAR'd, and the airlines used 9/11 as an excuse to rescue them from their already-existing financial woes.
(On the other hand, publicly-owned regional/commuter rail service in the US tends to be
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Think of it in the same way as with trains, you can start a train-business and start a route between city A and city B without building your o
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It kind of reminds me of when they slapped the Luxury tax on light airplanes. It played well with the people since if you can afford to buy a light plane you are rich. The problem was that combined with the stupid law suits almost caused the complete destruction of the light aircraft
Costs.. (Score:3, Insightful)
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so no you won't be replacing the whole of the airline fleets for 40billion dollars.
Re:Costs.. (Score:5, Informative)
71 Boeing 737s @ $50 million per
68 Boeing 757s @ $65 million per
75 Boeing 767s @ $140 million per
8 Boeing 777s @ $200 million per
63 MD 88s @ $40 million per
16 MD 90s @ $45 million per
68 CRJ 100/200/700s @ $24 million per
that brings this one airline's fleet cost to just about $25 billion. And I was giving the low estimate for the cost of the planes.
http://www.delta.com/about_delta/corporate_inform
only 369 planes? (Score:2)
Where on the plane is a unique ID that I can write down? I'm curious how often I've flown on the same plane.
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you can then use this page to look up basic info about the plane in question:
http://registry.faa.gov/aircraftinquiry/NNum_inqui ry.asp [faa.gov]
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They carry around cameras and binoculars viewing planes, taking pictures, and writing down little things on paper, all the while arousing suspicion amongst their cabin mates. Once they get bored with all that, they ask the stewardess if they can visit the cockpit. A f
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Do they even let you do that anymore?
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Re:Costs.. (Score:5, Informative)
I don't know about airplane costs, but here is some perspective on other government upgrade projects... each upgrade involved both hardware and software systems.
The IRS attempted to update their systems (originally designed in 1962). The project began in 1999 and was spread over several 'projects.' The 1999 plan was eventually scrapped after the main database was already around 40 million over budget and way over deadline. Further attempts to modernize the system in a more compartmentalized fashion lead to the $318 million lost due to excessive tax refunds in 2006 (for tax year 2005 returns). The system responsible was also scrapped and the old one was put back into service.
Though not mentioned in the overview that I link below, a GAO report I saw a couple years ago put the total actual losses (internal/external/disaster recovery etc...) at several times the publicly reported loss numbers.
Here is a general overview: http://www.crn.com/it-channel/192502071 [crn.com]
The FBI attempted a complete systems overhaul (agents still can only use one search term in many of their databases, and much info is still paper file only). That was finally scrapped in 2005 after $170 million in costs, and over 170,000 lines of code... the project had been in progress for three years. The Washington Post put total upgrade costs since 9/11/2001 at around $600 million.
Here is a general overview: http://www.washingtonpost.com/wp-dyn/content/arti
I suppose the successes don't make as much news as the failures, but the real perspective we should be looking for here is who the F*** is going to plan and manage a project that will be responsible for our air safety? The upgrade attempts that I know of all ended with the old systems being put back into place.
NASA probably gets my vote. I have heard that their software design requirements and beyond insane, and that despite the catastrophic structural failures they have endured, the shuttle software systems are beyond rock-solid. They still use multiple levels of 'readers' to proofread every line of code as you would a thesis manuscript in addition to all other testers/unit-tests/sims etc..
Regards.
Forty billion over two decades . . . (Score:3, Interesting)
Hey, I know! Let's cut U.S. farm subsidies to the levels farmers get in Australia and New Zealand. Surely American farmers aren't so incompetent that even with the advantage of cheap Mexican immigrant labor they can't compete on an even footing with Australians, right? So cut subsidies by 80%. That'll generate, oh, seventeen billion dollars. We can update the air control system in just three years, then, and then let the money saved reduce the deficit.
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That would be zero.
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US farm subsidies (Score:2)
With respect, you seem to be under the false impression that US Farm subsidies actually go to American farmers in the first place. I'm not an expert (and stand to be corrected), but after a few minutes of anecdotal looking around, it seems
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God Bless Mode-S (Score:4, Informative)
http://web.mit.edu/6.933/www/Fall2000/mode-s/toda
Lots of technogibberish here: Hey, Wiley! When are you writing "Air Traffic Control for Dummies"?
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I only bring it up because I had almost forgotten the memory. It's not something that comes up in conversation often.
Talk about emotional scars for an eight year old kid.
Here is a brief link for anyone who wants a timeline: http://www.firefightersrealstories.com/cerritosair
Regards.
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Anon Poster: Check the MIT link. They say Mode S with a mod can carry GPS data. From the link: "The GPS Squitter has taken [Mode S], added more bits and in those bits, transmits information as derived from GPS.'' The Mode S extended squitter was demonstrated by Lincoln Labs and the FAA in Bo
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Call me old-fashioned, but I'd prefer Mode S with a ground radar. Without some form of ground truth to confirm the GPS broadcasts, what's to prevent spoofing of signals (triggering false collision warnings etc.) by "terrorists"?
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Tried controlling 11% of global airspace with radar?
http://www.airservicesaustralia.com/media/press_r
I hope... (Score:3, Insightful)
I hope there's also some contention about what will happen when those closer-together planes are left without GPS due to a war in the Gulf or some technical glitch, and the radar backup cannot keep up with the added traffic (if it could, what'd be the point?)
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Re:I hope... (Score:5, Informative)
How do I know this? Because it's in the public record. The airlines and their lobbyist have been spreading misinformation and FUD on a make believe funding crisis. They have been doing this to take control of the FAA. What? Ya, sounds odd, but here are the details.
Right now, ever ticket sold has a tax which pays for infrastructure costs. Plus, every gallon of fuel sold (per gallon tax) pays for infrastructure costs. The airlines, by far, are the largest users of FAA services. What they want to do is to have the per ticket tax waived, pocket it, reduce their tax on Jet fuel and increase the taxes on the planes that hardly or rarely use FAA services. On top of that, they then want to create a "user fee" system where the FAA is free to set their own rates. The want to charge for items such as weather briefing, landing fees, IFR (instrument flying) service fees, in route update fee, etc. This means two things. One, and most importantly, the FAA would no longer have to own up to Congress on how and where they spend their money. Which is sad because right now they can not even explain where some 20 million went. And two, the small guy would be expected to pay the airline's share in taxes. Worse yet, even by the FAA and airline's own admission, they would suddenly create a significant funding short fall.
In a nut shell we have:
o Airlines want per ticket tax waived so they can pocket it (ticket prices would not be reduced)
o Airlines want a tax reduction forcing small guys to carry the airline's tax burden
o The airlines/FAA and crying the current infrastructure will not pay for new tech deployment
o Both the FAA and airlines have finally admitted their scheme will fall short of the existing taxes by hundreds of millions. AOPA has been saying this for a long time using the FAA's and the airline's own numbers with VERY conservative accounting.
Contrary to the assertions made in the article, there are fewer planes flying now than there has been since the 1970s; which is the US's peak in aviation. Even the current infrastructure can handle the load. The FAA's concern is a new category of jet has been created; the Very Light Jet (VLJ). The problem is projections indicate the FAA's current tax schedule will be able to handle the growth until at least 2030.
Long story short we have the airlines and the FAA working to break free of Congress' funding oversight. Currently, the US's FAA model is considered the best model in the world for both funding and safety, bar none. In all other places in the world where user fees have been implemented, GA has been destroyed, costing thousands and thousands of jobs. Worse, most analysts exist aviation safety will begin to decline almost immediately as pilots will now be reluctant to use federal services because it costs a per use fee. This means more pilots in higher densities without being in contact with each other. Worse, this means more pilots flying into unknown weather conditions.
Long story short, the funding for this system is already well established. Any short falls will be addressed by congress. Their current effort is to break free of congress and create a windfall for the FAA and the airlines; as they would be free to charge anything they want for their services. If they get their way, US skies will very likely become a dangerous place to be, even in commercial planes.
If this concerns you, I highly recommend you contact your representatives and congressman to let them know you expect the airlines to pay their own way and you demand the skies remain the world's example of safety. Tell them absolutely no user fees.
If you want more information, please go to http://aopa.org./ [aopa.org.]
One last note, there is a FAA crisis looming. Right now, there is a mandatory re
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Just make sure it's not any young people you actually like. My wife and I have three children (and about 45 years combined in ATC), and we've made sure they understand all the good reasons NOT to follow in their father and mother's footsteps. 466 days to retirement....
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What about.... (Score:4, Insightful)
A single plane that will have a broken device, and wont transmit its position properly will have the option of taking down a lot of stuff.
Whatever the shortcomings of the current radar system, radars tend to work regardless of the planes condition, and regardless of its position.
Heck, IIRC planes only need special equipment to identify themselves, not to tell if they are actually there, and where they are.
Sorry - but i prefer false positives (radar ghosts, or whatever their names) from false negatives (nah, its not a plane, it doesnt have GPS, it must me a bird. [15 minutes later] OH F*CK, EVERONE - RUN!!!....).
If its not going to replace radar systems for good - i see no point in spending 40b, and i dont see how it can replace them - given the requirements for such systems.
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also, from what i can tell it takes everywhere up to 30 seconds to get a decent lock on gps. 30 seconds doesn't seem like much, but now lets see how much 30 seconds matters in a jumbo doing 1000miles an hour. if your gps loses it's lock for some reason, that's a scary amount of time to be flying blind.
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Most consumer grade GPS receivers quote cold start times of 45 seconds, warm start 15 seconds (no idea if the expensive things they will be using on planes are better). Cold start basically means that you haven't seen at least 4 of the satellites that are in view for several hours, so losing the lock on all the satellites for a few minutes is only going to cause warm-start conditions at
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Heck, IIRC planes only need special equipment to identify themselves, not to tell if they are actually there, and where they are.
That's incorrect. ATC radar does not supply the 3-D position of the aircraft, it can only see range and bearing. The height is supplied by the transponder on the aircraft (the same that also broadcasts its ID code).
Perhaps not a good idea: (Score:4, Insightful)
Which means that if there is a solar flare or something of the sort, the potential for disaster is enormous. Loads of planes flying around close together using a system that depends on vulnerable satellite links.
This is also assuming that air travel continues to expand. I know that /. is full of posts from global warming deniers, but now that even the politicians are starting to do things rather than talk, this could be a system that takes 20 years to implement and then is redundant.
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The chances of a solar flare killing a significant proportion of the GPS satellites seems very remote.
Loads of planes flying around close together using a system that depends on vulnerable satellite links.
The GPS ranging sats are in reasonably low orbits so not especially vulnerable to solar activity. Of course, they may be requiring SBAS signals too, which rely on a small number of satellites in GEO
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Ease The Pain (Score:3, Insightful)
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A few more data points (Score:3, Insightful)
Responding to some of the (typically) under-informed criticisms...
(Why bother to understand a topic when you can quickly post an opinion?)
This isnt intended to replace all traffic management, for instance at airports, just to lessen the overhead of overseeing the more predictable long stretches in-between.
Aircraft spacing would be lessened under the proposed system but still be considerable. Therefore even if GPS accuracy were degraded by the US Military it wouldnt have much practical effect. Besides accuracy to a few hundred feet is already problematic when youre traveling that far every second.
The new systems arent any more susceptible to interference from solar flares or other natural phenomena then current systems; indeed theyre predicted to be more robust.
Finally, 40 billion dollars US does seem like a lot of money. But considering the FAAs historic phenomenal mind-bogglingly beyond-grossly-incompetent record [findarticles.com] at managing system deployments its probably a low-ball on a cost-plus contract...
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Well, yeah -- it's the FAA's unimpressive record that worries me. I'm sure these guys understand ATC better than I and other /. readers do. But do they really know what they are doing?
And what about failures? (Score:3, Interesting)
The best way would be a (distributed) radar system + GPS.
You need both system failing in order to get an airplane lost.
GPS Guided SAMs (Score:2)
I would have thought that tracking regular GPS transmission significantly simplifies steering rules for a r
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In theory, yes. But you'd have to design and build such a missile first, and that isn't trivial. Much easier to steal a current-generation infrared-guided SAM instead.
And for the FAAs next trick... (Score:5, Interesting)
Part of the issue is the FAAs view that it knows best (despite the evidence to the contary) so when new approaches to ATC are created elsewhere (mainly Japan and Europe) they push back against them and try and create their own solution. They are continually trying to take the short cut (expensive short cut) with some new technology gizmo rather than doing the hard way of actually planning a pan-USA federated ATC system with a single upper airway controller and decent federation around the major hubs and then delivering that incrementally focusing on the key cruch points in the existing systems. They just look for the silver bullet.
The FAA is a case study on how not to do large scale IT, and a case study on how not to learn from others.
Why does the FAA think it can do it this time? (Score:2)
Why on earth would anyone think that the FAA, who have delivered bugger all in 30 years, will be able to deliver now? I
Not Invented Here Syndrome (Score:2)
There's already a tested, approved and standardised system; follow links in this page for info. [www.gpc.se]
But the inventor [wikipedia.org] has for a long time been harassed by various US instances, in order to facilitate US interests, and that's why you won't see it in the USA.
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The article refered to by slashdot is nothing more then a advertisment for the NextGen system. It askes no critical questions and totally avoids the subject of internationalization of the system. But of course that does not matter, cause its not like airplanes ever go between countries, right?
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Where "funding" comes from. (Score:3, Insightful)
Actually, there's absolutely no doubt where the money will come from - we the people. The contention is whose hands it will go thru first before the system is complete. The "who pays for it" question is a distraction in many, many public projects, such as "who pays for a cleaner environment?" "Who pays for (existing | preventing) illegal immigration?", etc.
In a way, it can be said that governments and companies have no money at all, except that which they receive from individuals. For example, car makers objected massively to adding airbags, and one excuse they pulled up was cost. But who pays for every part of the car when it's bought? Car makers? uh, no. Every added cost to everything is always passed on to the people who buy products and use services. It must be, or the companies providing products and services would eventually go out of business.
The "who pays for it" debate is always part of the push and shove of hogs eating out of the gov't trough. Sadly, most people don't get this at all.
Homeland security will love this (Score:3, Insightful)
Why can't we extend this system to cars? Scrap all the cops' speed measuring equipment and just wait for phone calls from speeding gps equipment wanting to fess up?
No, i didn't rtfa
India calls it "GAGAN"; to be operational by 2008 (Score:3, Informative)
wiki page [wikipedia.org]
Details in google's cached [64.233.167.104] copy of the announcement.
Google search would also get more details on this.
...you mean they don't use GPS already..? (Score:2)
FAA Smoke and Mirrors (Score:4, Informative)
I would suggest everyone read Michael Boyd of Boyd Aviation, an aviation consulting firm, that has been highly critical of the FAA and over a decade ago brought the idea of "Free Flight" to Congress but since that time has been ignored. Boyd has his pulse on the aviation world better then anyone I know and writes a column each Monday.
http://www.aviationplanning.com/asrc1.htm [aviationplanning.com]
Root Cause of the Problem (Score:2)
I am sure that this is great technology, but it will only encourage the airlines to continue to switch from large aircraft to so-called regional jets [wikipedia.org]. Since the total number of people flying is either stable or increasing, the net result is that there are more smaller aircraft in the air today that ever before. That's what's causing the delays.
Salon recently published a good description [salon.com] of the problem, written by an airline pilot [askthepilot.com].
save us (Score:2)
GPS, ADS and position reports (Score:2)
I'm trying to find out when GPS was first introduced in the skies, but some posters seem to think this is a new techno
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The real cause of delays (Score:2)
Over at Salon (ad-view required for non-registered users), Patrick Smith has had a convincing couple [salon.com] of articles [salon.com] making the case that delays are a side-effect of airlines using more smaller airplanes to move passengers around with more flexibility. More operations (take-offs and landings) with fewer passengers per operation means airports
So, how many GPS satellites can China shoot down (Score:3, Insightful)
Could someone please explain (Score:2)
The only caveat is that the system for flying the aircraft not use Windows in any way, shape or form.
Peanuts! (Score:2)
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In practice, three satellites are adequate for ground and altitude calculation (since most other spatial possibilities can be ruled out as being 'ridiculous').
For more info: http://www.beaglesoft.com/gpstechnology.htm#Triang ulation [beaglesoft.com]
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Re:Altitude? (Score:5, Informative)
For higher altitudes, the altimeter usually measures the air pressure. This isn't a problem-free method. You have to set the altimeter before each flight (to compensate for the height above sea level of the airport you're at). It's also not very accurate, as the indicated height varies with the barometric pressure. Incorrectly-set altimeters have been known to cause crashes.
A GPS altimeter would solve all this. Connect the GPS unit with a terrain map, and you're even better off: you'll know both your altitude above sea level, and above the local terrain.
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Actually, the engine was fine. It just no longer had a connection to the prop. Same result.
Oh, you can test the auto gear extension system in a Piper Arrow by leaving the cockpit vent window open on takeoff. Added another item to the pre-takeoff checklist after that one.
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No reason why it wouldn't show altitude. GPS altitudes generally aren't as accurate as ground positions (it's a geometry thing -- you'd need a satellite high overhead, which you rarely have, to get good altitude). But they should be good enough. Besides which, the pilot isn't usually concerned so much about his own altitude. He generally knows that. He's worried about the altitude of other aircraft in his neighborhood.
Re:Altitude? (Score:4, Informative)
TCAS is a traffic collision avoidance device also in use today that transmits altitude data between aircraft. Again the data comes from the altimeter.
Automatic Dependant Surveillance (ADS) data provides position (from INS or GPS) and altitude from the altimeter. The data can be sent via radio link or satellite. The amount of times per minute (or hour) that this data is updated to the ground station provides the basis for seperation of aircraft. If you update quite often you can run planes just a few miles apart. If you update every thirty minutes or so by expensive satellite links (trans-ocean) you might have to run the aircraft 100 miles apart. Some of the cost is in the aircraft but much of the cost is in ground station receivers, computers to interpret the data, displays to show the aircraft positions and then training for everybody along the line to use it.
The benefit is in better routing and less time in the "stack" when you arrive. Less fuel burnt is a cost saving but also think in total cost per minute of crewing and running a 747. It costs a bundle to switch to this but the longer term savings are far greater.
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The altitude calculated by the GPS is way more imprecise than the value measured by the altimeter.
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Remember how
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No way I'm going to board a plane that only relies on RADAR. RADAR does only work if the airport has electricity, you know. And electricity is far less reliable than plain eye sight. I don't want to trust my life on the optimistic hope that electricity hickups won't be happening when I'm traveling, or that the RADAR will have a mechanical problem just when we're approaching an airport in fog at
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The radars used for traffic control often supply only a 2-D picture (range and bearing coordinates). Height information is supplied by a transponder on the aircraft (this system is called SSR [wikipedia.org]). Transponders have been known to fail, or be set incorrectly (which means the aircraft is misidentified).
Also, the current system means that the air traffic controller has to match a radar blip to a transponder signal. AFAIK, this is done man
Re:keep it (Score:4, Informative)
And satellites are far less reliable than radars.
Care to qualify that statement? Satellites are pretty reliable (I'd be inclined to say a single satellite is probably more reliable than radar, although I have no figures to back this up). Afterall, satellites are designed to run without maintenance whereas radars are not, so it makes sense that radars would be less reliable.
In addition, you would need to lose several satellites at the same time to render the GPS inoperable.
I don't want to trust my life on the optimistic hope that solar flars won't be at peak when I'm traveling
As mentioned above, you would need to lose several satellites at the same time to cause a problem.
Additionally, which is harder: disrupting radar systems, or shooting down a few satellites ?
Disrupting radar is probably a lot easier to do than shooting down several satellites.
which is harder: sending a few people to fix a broken radar in a few hours, or sending people up to fix a satellite in six months ?
NAVSTAR has been running for a long time without much trouble. There are more than enough satellites to cope with a few breaking at any one time and the satellites are fairly routinely replaced and deorbitted with no disruption to the service.
how many satellites would we need to cover reliably the whole planet before they can switch totally to GPS
24 satellites are required to cover the whole planet - there are currently 30 in operation.
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Oh really!?!? I know of a half dozen radar failures at the Cleveland regional air traffic control center over the last 15 or so years, there have been no failures in the GPS system in that time. Besides, it's not like they will fly only with GPS, they will have WAAS and internal gyroscopes along with ground radar and onboard collision avoidance systems using earlier methods including radar on many planes. We already have worlwide coverage with GPS and with t
Your bag will get there... (Score:2, Funny)