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World War II Tech eLoran Deployed As GPS Backup In the UK
hypnosec (2231454) writes General Lighthouse Authorities (GLA) has announced that they have deployed a World War II technology called Long Range Navigation system, which they have named eLoran, in seven ports across Britain to serve as a backup for the existing Global Positioning System (GPS). GLA notes that modern ships have a lot of equipment that rely on Global Navigation Satellite Systems for functioning and in case of failure the consequences will be disastrous. For this reason technology that doesn't rely on the GPS was required as a backup. eLoran is a ground-based system rather than satellite-based and is designed to be used in the event of a GPS failure. The system was quite successful and post-WWII era, the system was updated and crowned a new name Loran-C. The navigation system was adopted by mariners across the globe and was used until GPS was deployed. Loran has now been renamed as eLoran because of the upgrades to the technology as well as the infrastructure. The more accurate system generates longwave radio signal, which is 1 million times more powerful than those from positioning satellites, are capable of reaching inside buildings, underground and underwater. According to GLA, eLoran and GPS are quite different from one another and hence there is no common mode of failure.
Funny how two countries can take the exact same situation and arrive at completely opposite decisions.
I remember loran from my early ham radio days (50's and 60's). It made a hell of a noise on HF. It probably would not bother anyone any more as the hf frequencies are not utilized as they once were. Sounds like an excellent idea as the gps system is very vulnerable.
The primary risk to GPS in the UK is the USA deciding to turn it off.
That risk doesn't apply for US shipping near the US, as if GPS was turned off - rather than severely degraded - so would the local LORAN locators.
GPS is not going away unless someone actually presses the button.
It's not vulnerable (theoretically) to single points of failure (ideally) as it's intended to carry on even in the event of moderate wars.
No common mode of failure? An EMP or nuke would beg to differ.
Silence is a state of mime.
I thought the only reason we have technology is because of space? Only space makes us explore and has spinoffs?
How did they have a positioning system before Sputnik?
Betcha even if we never send anything else into space ever again, our information and signal processing technology can get so good we can make a GPS with nothing but terrestrial equipment.
They're just thinking long term for the coming low-energy, low-profile future.
In the event of a war with a major world power, GPS will be destroyed, because most of those powers have proven they can shoot satellites. If you depend too much on GPS you will be in for a rude shock when it goes away.
This is not your old 70's LORAN system. Thanks to advances in DSP processing, eLORAN gives your position with precision comparable to GPS (10m or so). It also have data channel that's used to broadcast DGPS corrections, so it complements GPS nicely.
Because of low frequency, signal penetrates buildings and ground (however with greatly reduced range). This may be one of the solutions for a car navigation in tunels. Even if it produces less precise position, it's always better than no position at all.
Great contrast between UK and USA, where LORAN transmitters were demolished in the past years. When so many things dependd on GPS signals, we really need some backup system for precise timing and positioning. Not thinking about backup only means we will learn about it the hard way - and it will not be pretty.
in case of failure the consequences will be disastrous
Yeah, because no shipping ever occurred before LORAN or GPS. What a joke! It's not like people found their way around the globe for centuries using the sun, moon and stars.
Does it work with existing receivers, that might still be present in some old aircraft?
I just viewed a description of eLoran at:
www.ursanav.com/ sites/ default/ files/ pdfs/ news/ UrsaNav%20ILA-40%20eLoran%20System%20Definition%20%26%20Signal%20Spec ification%20Tutorial.pdf
and scaned for the words: security, encription, jam. Nothing. Looks like there's no provision for these...
In case anyone is intersted, this slideset gives a nice overview of this "WWII tech".
http://www.ursanav.com/sites/default/files/pdfs/news/UrsaNav%20ILA-40%20eLoran%20System%20Definition%20%26%20Signal%20Specification%20Tutorial.pdf
I just viewed a description of eLoran at: www.ursanav.com/ sites/ default/ files/ pdfs/ news/ UrsaNav%20ILA-40%20eLoran%20System%20Definition%20%26%20Signal%20Spec ification%20Tutorial.pdf and scaned for the words: security, encription, jam. Nothing. Looks like there's no provision for these...true?
AC is correct. Jamming GPS (or equivalent other satellite system) is trivial and has been done. It's a major system weakness.
Please understand that the technology to kill satelites has been around for a long time. Several military contractors for the US Defense Department have developed kinetic kill vehicles. They are in orbit as we speak. Their purpose is to destroy satelites by ramming into them at high velocity. They are like an anvil with a guidance system and a simple propulsion system. I know that Boeing had these back in the early 1990s. I'm sure there are hundreds or thousands of them up there by now with their targets locked in. If the US has them, you know the Russians and possibly the Chinese have them. If there is a major war between any of the major powers on Earth, the satelites will be one of the first casualties.
Also, of course, the Chinese proved they could destroy satelites from the earth by their launch of a missile at one of their own several years ago. (Thanks for the space debris, China.)
Nice to know the grown-ups are in charge of strategic planning in the UK. Contrast the no-intellect kiddies and political scum in the USA. Congress passed an appropriation in 2008 to implement eLORAN, but some puffed-up asshat in the executive branch zeroed out the funding and nobody ever followed through.
Positioning systems for civilian purposes shouldn't be space based due to obvious issues with satellites (expensive, hard to maintain, etc). Hopefully, at some point, we'll have positioning systems that don't require any infrastructure all. Would be nice if they could tell the position from landmarks, the sky and Earths gravity field. ;)
Um.. electricity? Without it, pray for clear skies, a sextant, and knowledge how to use it.
“He’s not deformed, he’s just drunk!”
I read the title as "World War II Tech DeLorean Deployed As GPS Backup In the UK".
Followed by "They had time travel in WW2?"
Get free satoshi (Bitcoin) and Dogecoins
... announced that they have deployed a World War II technology called Long Range Navigation system, ...
It must have been something you assimilated. . . .
It's not "WW II", technology, it's late 1950s LORAN-C technology. LORAN-A was WWII. It's good to have this as a backup. Many aircraft still have LORAN-C receivers. It's good enough to find an airport.
How come slashdotters always write it as HAM? It's ham radio, not HAM. Despite rumors, it does not stand for Highly Antique Morse.
I saw a documentary on a US Navy Aircraft Carrier, it had a relevant incident. The carrier has GPS, LORAN, inertial navigation, etc. Yet every day a sailor steps outside the bridge with a sextant and takes readings on the horizon and sun. (does another sailor do so at night with the stars?). He then goes inside and using a WW2 manufactured mechanical chronometer calculates the position of the ship. When asked why the Navy still uses such ancient mechanical technology the sailor replied that this ship is a warship and is expected to be where it needs to be regardless of whether the fancy electronics is working or not.
LORAN stands for LOng Range Aid to Navigation. The original system, LORAN-A, was not all that accurate, but was very consistent. Fisherman and other mariners collected error corrections in hand-written notes which they applied to LORAN-A readings to get accurate fixes. LORAN-C was a newer system that ran in parallel with LORAN-A for a long time. In the early 1980s I used both pending on the coverage in any given location. [The U.S. Navy, however, decided on OMEGA as the next big thing and in 1982 decided it was ready for prime time. While my ship was at anchor, OMEGA had us underway on a course of 080 with a speed of 17 knots. My navigator was quite amused. We never used OMEGA again.]
I'm not sure how GPS can fail? There are like 26 or so satellites over the earth. I can't imagine all 26 of them going down all at once? My tablet can track 12 GPS satellites at once. Even in a city with buildings around me, the tablet can track 5 out of 12 satellites. Maybe I am missing something.
Its used in Australia as well, in parallel with GPS and radar. The aircraft transmits a signal, and multiple ground stations compare the arrival time.
http://michaelsmith.id.au
but you were moving. It was just not calibrated yet to compensate completely for the rest of the movements you were doing (around the earth, the sun, the galaxy, local group movement etc)
I was thinking of Global Liberation Army from Command & Conquer: Generals (C&C:G). :P
Ant(Dude) @ Quality Foraged Links (AQFL.net) & The Ant Farm (antfarm.ma.cx / antfarm.home.dhs.org).
If the following blog post is worth anything, then maybe the USA will still go with eLoran as a backup:
http://www.panbo.com/archives/...
The next question is how cheap is the most affordable eLoran receiver, and where can one be bought?
Jumpstart the tartan drive.
That was probably LORAN-A, with which we used to share the 160m band (1.8-2.0 MHz). LORAN-C operates (or operated) in a dedicated allocation at 100 kHz. LORAN-A was shut down quite a few decades ago.
LORAN-C would probably be rather resistant to EMP. Like just about everything military, the transmitting equipment would be designed to be EMP-resistant, and receiving equipment on vehicles would not be particularly susceptible. It's stuff with long cables that picks up EMP. LORAN-C is certainly much more jam-resistant than GPS. The transmitter power levels are/were enormously higher, some in the megawatt range, to overcome natural background noise and antenna inefficiency. Even the large towers used are only a small fraction of a wavelength (3 km). Also, LORAN-C operates by groundwave propagation (that's why the frequency is so low) so it's not very sensitive to solar activity.
I certainly wouldn't bet that GPS satellites couldn't be destroyed, but most anti-sat weapons demonstrated so far work only on low altitude orbits. The US systems consist essentially of lobbing a small suborbital missile up in the path of the target satellite. Destroying a GPS satellite in a 20,000 km orbit takes a much bigger launch vehicle and considerably more time, and would be much harder to conceal from US space sensors.
Jamming and spoofing are the much bigger threats.
In Britain in world war 2, aircraft would fly hundreds of miles using dead reckoning (initial position, compass direction, airspeed, wind direction). If anything changed, or you had to do maneuvers to protect life and limb, you may lose track of time/distance/direction. Its bad to lose a plane because 'lost, tried flying home, crashed in ocean' or 'lost, tried flying home, had to crash behind enemy lines'. So they had two low frequency long range beacons: Cat and Mouse. Mouse was in Northern Scotland and sent a signal. A precicely timed signal (with respect to the mouse signal) would then be send from South England: "Cat" (cat chases mouse). Loran-S (nighttime use) could provide signals south of the North Coast of Scotland, east as far as Poland with an accuracy of 1/2 mile (skywave long baseline Loran). Considering they were operating at 1.95 MHz, it was 1943 and the first transistor was still 4 years away, that's not bad.
GPS L1C signal have 60W (a few times more on newer GPS sats) of power being irradiated by the antenna. By the same that signal travels 18000Km to the ground its down to miliwatts, in fact so weak that a one watt transmitter one Km away can still overpower the original signal. A 1 watt jammer can fit in your pocket. A 100 Watt jammer (no more than the size of a suitcase) can jam GPS for a hundred Kms easily.
GPS works great as long as its not jammed. And the dangers are far worst when there's a signal being spoofed (artificially sending a signal that looks genuine, but has the wrong parameters, potentially leading to aircraft crashes, banking transactions recorded with the wrong timestamp, shutting down celullar towers, leading people to the wrong locationto name just one of the dozens of life threatening scenarios).
eLoran is the only solution that can actually compliment GPS, providing it with a signal of similar accuracy to GPS L1C that can be received without line of sight to the antenna transmitting the signal 1000 Km away from the antenna.
In my opinion destroying the Loran-C towers was the single worst decision the Obama administration made. The Loran-C signal was worthless, but the towers and adjacent building could have been shutdown and then repurposed to transmit eLoran.
The Seneca LORAN-C station in upstate NY between Rochester and Syracuse, while silent, didn't destroy it's tower or buildings - instead it was taken down one section at a time - and is stacked neatly in the parking lot. Wonder if it's simply been mothballed in case they need to reactivate the system?
http://tinyurl.com/senecaloran