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Author Topic:   Navigational Absurdity
jimh posted 03-17-2012 07:49 AM ET (US)   Profile for jimh   Send Email to jimh  
GPSWORLD.COM has an excellent article about the decision by the Obama administration to kill the LORAN system. I don't think I've read a better account of this anywhere. The author, Don Jewell, has been involved in electronic navigation for most of his career and holds a Ph.D. degree. He tells the tragic tale.

LORAN-C has been around since World War II. I among many other aviators used it extensively in Vietnam, and frankly for many countries and users today it is still a totally adequate service. With USCG expertise and support for 52 years, LORAN-C provided unparalleled timing and navigation services around the United States and Canada until the pretender known as GPS came along and dethroned the aging monarch.

Now, that may sound like a natural sequence of events, except that LORAN-C was in metamorphosis, 80% of the way through the process actually, of morphing into a new digital (1990s era technology) LORAN know as eLORAN or enhanced LORAN with better, more reliable transmitters, smaller receivers, and a virtually jam-proof signal structure. Many likened the legacy eLORAN to a strong ground-based GPS with coded signals for security. All that was in place and 80% complete when the whole process was killed by an administration with a strong Luddite orientation and subsequently the bean counters pulled the plug in 2010, despite recommendations to complete eLoran from both the Department of Transportation’s Positioning and Navigation (PosNav) Committee and the Department of Homeland Security Geospatial Committee and the strong personal support of the DOT Undersecretary for Policy and the DHS Deputy Undersecretary for Preparedness and National Protection and Programs. My sources tell me the Office of Management and Budget (OMB) was determined to do away with Loran-C and facilitated its ultimate demise. An unfortunate theme we have seen played out much too often: Non-technical people forcing ill-advised technical decisions. In a country whose greatness has always been its technical acumen, willingness to take risks, and self-assurance, OMB stands as a chilling element of focus today…but, that’s a subject for a future article.

Since that time the U.S. Coast Guard spent more money dismantling the legacy LORAN-C infrastructure and antennas than it would have taken to complete the 20% upgrade for a full transition to eLORAN. Taking down the Port Clarence, Alaska, tower, the video of which was a YouTube favorite for many weeks, cost an estimated $8 million. The destruction of the towers in Attu, Shoal Cove and St. Paul were probably on average $5 million each. With the tower removal in Baudette, Minnesota, the cost of removing Loran towers to date cost close to $25 million. One could argue that the administration created some jobs in these “shovel-ready” tower tear downs, but I have no doubt that a better use of the funding would have been to deliver a robust positioning, navigation, and timing backup for the nation. But alas that is ancient history in the technology world, a whole 18 months to be exact.

For the full article, visit eloran-and-ursanav-timing-everything-12744

Mambo Minnow posted 03-17-2012 12:06 PM ET (US)     Profile for Mambo Minnow  Send Email to Mambo Minnow     
Department of Defense will regret this decision in a conflict when an adversary takes out our GPS constellation. It's not just a bad decision for the recreational user.
Hoosier posted 03-17-2012 09:49 PM ET (US)     Profile for Hoosier  Send Email to Hoosier     
Here's the dirty little secret that "they" won't tell anyone, a good solar flare will not only take out the GPS satellite transmitters, it'll take out the receives too. So, even if the satellites come back on line there will be no one there to listen to them. It's the same effect that takes out power grids, I think it's called front end overload, you fry the front end of the receiver. Anyway, it's not a bad idea to lean how to use a sextant.
jimh posted 03-18-2012 12:28 AM ET (US)     Profile for jimh  Send Email to jimh     
The irony of GPS is that is provides a global navigation service. The USA is spending billions of dollars, and everyone in the world benefits. The LORAN system was only useful in the USA. As I recall the annual operational cost for LORAN was only $13-million, which is less than they're spending per year to decommission the system. Stop the madness!
AZdave posted 03-18-2012 02:06 AM ET (US)     Profile for AZdave  Send Email to AZdave     
I don't mean to be contrarian on the topic, but I don't remember ever having a conversation with a person who used LORAN as a primary or secondary navigation aid. Have I led a sheltered life?
jimh posted 03-18-2012 08:14 AM ET (US)     Profile for jimh  Send Email to jimh     
Dave--You must have started boating after 1995. LORAN receivers never were as inexpensive as GPS receivers have become now. I think a LORAN receiver never got below about $500. A GPS receiver these days is about $15 for the chip, and $35 for a complete receiver assembly. LORAN receivers were never built into 100-million mobile devices that were used by the general public. But LORAN was a working system, already in place, and it cost very little to maintain it and improve it. LORAN signals can be received many places that GPS signals cannot and never will be able to be used.

A LORAN station cost almost nothing to build, compared to a GPS satellite, and only about a dozen are needed to cover the continental USA. I think the cost of putting a single GPS satellite in orbit must be about $1-billion--and you need a minimum of 24 satellites in orbit for GPS to work. LORAN could have been maintained for the next century for less than the cost of one GPS satellite. LORAN signals cannot be jammed or disrupted as easily as GPS signals--they're much stronger signals.

L H G posted 03-18-2012 12:53 PM ET (US)     Profile for L H G    
As far as I'm concerned, Loran operated in it's own little world of Lat/Lon innaccuracy and complicated Loran overlay grid on nautical charts that nobody could understand. Its repeatable accuracy to inaccurately described positions, was as good as GPS, but that's about it. It rapidly became an obsolete, throwback, old technology system, just like 2-stroke carburetors! Or maybe even a dinosaur, like the new Mercury 150 EFI 4-stroke recently discussed here after it's introduction.

I had Lowrance top of the line Loran on my boat, purchased new in 1989. It was expensive. I later found out it was highly inaccurate on Lat/Lon, which is how we identify where we are on this planet. When I tried to sell it 6 years later, I found it was obsolete and worthless and ended up throwing it in the garbage.

I had a large collection of waypoints, about 200, saved on my Loran, which also gave me the corresponding Lat/Lon positions. When I copied them over to my new Lowrance Differential GPS system, entered manually, I found they were HORRIBLY INNACURATE positions. Some were off as much as 2 miles and basically worthless. I had redo the entire

It was also worthless in the Bahamas and some parts of Canada.

The manufacturers quickly stopped making these machines, and to 99% of boaters, the GPS systems are superior. The marketplace quickly determined that Loran could not compete with GPS for any number of reasons. We all knew Loran was dead. This was nothing new.

Maybe this author has some political agenda?

jimh posted 03-18-2012 01:15 PM ET (US)     Profile for jimh  Send Email to jimh     
Larry's historical recollection may be earnestly presented, but it omits many important points and is an inaccurate representation. Let me correct a few of the inaccurate impressions he has created.

LORAN and GPS actually determine position in almost exactly the same way and both systems are subject to exactly the same sort of errors. However, LORAN has a considerable advantage in that the precise location of its signal sources is fixed and extremely well-known, while in GPS the signal sources are satellites in orbit, whose precise position is subject to some variation from orbital mechanics and must be calculated very precisely on the fly. Both LORAN and GPS are subject to errors in signal propagation, but both can be corrected using similar techniques.

Position finding in both LORAN and GPS is done the same way, but in GPS devices we are now blessed with microcomputers that do all of the mathematics and calculating, giving us a latitude and longitude for position

When LORAN was operational there were NO low-cost micro-computers which could be used to produce instantaneous conversion of line of position based on delays into latitude and longitude. The conversion was done by the navigator using the LORAN time delays over-printed on charts.

LORAN positions were quite repeatable and the system accuracy was much higher than Larry's recollection of two-mile errors.

In the LORAN era there were no low-cost electronic chart plotters and no publicly available electronic cartography at any sort of price. There were no electronic chart plotters.

If the same advances in microprocessors and digital electronics were applied to a navigation system using LORAN, and if the LORAN signals themselves were increased in accuracy using modern techniques, and if a differential augmentation system like the FAA's space-based augmentation system WAAS were applied, LORAN could produce position fixes of an accuracy comparable to GPS. It could do this at a much lower operational cost--no billion-dollar spacecraft and billion-dollar rockets needed.

Please remember that LORAN as it was experienced by older boaters like Larry was a navigation system implemented with 1950's technology. The fundamental concept of the system is very good, and if it had been permitted to be modernized to 2010 technology, and if receivers were produced in mass quantities like GPS receivers, the cost and accuracy of LORAN would be very similar to GPS.

jimh posted 03-18-2012 01:22 PM ET (US)     Profile for jimh  Send Email to jimh     
Larry's representation of LORAN as worthless outside the USA is wrong. LORAN was and still is implemented on a global basis by a number of nations, and it is still in use. If coverage in the Bahamas was a goal, the nation of the Bahamas needed only to put up a couple of LORAN stations--unless you think the USA should do it for them.

This is one of the political absurdities of killing off LORAN. It cost a few pennies to run compared to GPS, and it was a benefit only to the USA. Instead we spend billions on GPS and let the entire globe use it for free. Many citizens do not realize that providing a free global navigation satellite system to the rest of the planet is actually one of the best ways to general goodwill toward the USA.

Another obvious benefit of LORAN was the very easy access to the signal sources for upgrades, repairs, and maintenance. LORAN stations are on the ground. You do not need to replace them every ten years. You do not need a space vehicle to get to a LORAN station.

Killing off LORAN was one of the dumber moves by the Obama Administration. However, given their craziness in trying to let a billionaire investor make a killing with LIGHTSQUARE at the expense of 300-million GPS users, it is not surprising. The position, navigation, and timing industry does consider Obama to be much of a supporter or friend.

jimh posted 03-18-2012 01:42 PM ET (US)     Profile for jimh  Send Email to jimh     
Larry writes about an author who has revealed the craziness of killing off the LORAN modernization when at the 80-percent complete state as follows:

Maybe this author has some political agenda?

Larry--I think you are correct. The agenda here is to enlighten the citizens of the USA about the crazy decisions made by our government in regard to LORAN. I think the fellow likes to see the citizens of the USA get their money's worth from federal spending. We could have had a modernized LORAN as a back-up navigation system for a few million dollars. Instead all we are getting is a youTube video of big towers being blown up, a lot of welfare cheese, and more ethanol in our gasoline fuel.

L H G posted 03-18-2012 11:39 PM ET (US)     Profile for L H G    
Jim, in this statement, you misunderstood my criticizm of Loran

"LORAN positions were quite repeatable and the system accuracy was much higher than Larry's recollection of two-mile errors"

As an example, I saved my Loran waypoints ON LOCATION, such as the Ft Lauderdale inlet, or the Chicago harbor entrance.
The Loran then showed those positions both as time delays from two towers, and translated it into Lat/Lon.

When I entered those same Lat/Lon positions in the GPS, I found they could be off as far as 2 miles. The Loran Lat/Lon positions were worthless. Almost none of the 200 were anywhere near accurate in Latitude and Longitude. Loran was lousy at Lat/Lon position on the surface of the earth, which was why it had to be discontinued. The GPS system gives highly accurate position in Lat/Lon, and from maybe 8 sources rather than two or three.

I see no reason to trash GPS or the Obama administration for ending it. If McCain would have been elected, he would have ended it also. We have to quit living in the past with this kind of technology. Loran will not be coming back and is dead.

gusgus posted 03-19-2012 01:27 AM ET (US)     Profile for gusgus  Send Email to gusgus     
This has become political in a sense that we seem to be seeing a supporter of the current administration and some how knowing McCain's presidential aspiration alternate ending.
Come On LHG, you might be psychic, but even Gene Dixon herself wouldn't suggest Senator McCain would have made if voted into office, these specific decisions.

The feeling I have is an overwhelming sense that this current administration is H&!! bent on destroying the past successes in almost every area and subject in America.
Loran is cheap and just as smart as carrying a second bullet while hunting, a spare tire while driving, or a life jacket while boating, Loran is and was a safety net, like one of those "donut" spare tires. Far from perfect, but it would still get you home. It was not free, and last time I checked either were bullets, spare tires or life jackets.

I suggest we all think really thoughtfully about our patriotism and our countries future. Think about our countless dead countrymen, who gave it all for our rights. Think about our nation a little bit more than only of ourselves.

I bought a sextant, now to learn how to use it, Thanks Obama for the possibility of gaining that skill level.

jimh posted 03-19-2012 08:16 AM ET (US)     Profile for jimh  Send Email to jimh     
Larry--You are giving more misleading information.

You can't ascribe to LORAN the failure of your computer algorithm to convert some observed time delays into a position. That is a failure of the computer algorithm you were using. LORAN time delays were quite accurately printed on government charts. If some device you owned could not convert them to latitude and longitude it was a shortcoming of the device, not of LORAN.

LORAN and GPS are both radio-locating systems, and work in similar manners. The location of the signal sources and the frequency of the signals are different. LORAN uses TDMA for the signals and GPS uses CDMA.

The modernization of LORAN consisted to two parts. The accuracy of the signals being transmitted was being improved. In GPS, each signal source has its own cesium atomic clock to maintain time accuracy. This sort of precision was being added to the LORAN signals. In GPS there are several augmentation systems that enhance accuracy. This sort of augmentation could have been added to LORAN, too, and its accuracy would have improved. The second part of modernization would be more sophisticated receivers. Think back to the 1950's and imagine the complete lack of any sort of low-cost low-power digital computing resources available. LORAN worked without computers. LORAN could have worked much better with computers. There is more mathematical computation going on in a GPS receiver these days than was used in the Apollo moon shot. GPS receivers have a bit of an advantage. If more computing power were included in a LORAN receiver, the system could be improved. And we know that computing power is very inexpensive these days. It costs almost nothing to add enormous computing power to a device now.

prj posted 03-19-2012 08:39 AM ET (US)     Profile for prj  Send Email to prj     
LORAN was old and obsolete technology reserved for the HUMANOSAURUSES amongst us. No one under the age of about 45 has even seen an operational unit aboard a pleasure craft in their adult years.

One could cling to the obvious and not worth repeating benefits of a wired dial- up telephone as well, but we don't wax nostalgic about that device and maintain one for operational redundancy and superior audio performance.

Progress marches along, and perhaps this step is just one difference between a hypothetical President Great Grandfather McCain and the middle aged Obama, or perhaps this decision was all but a foregone conclusion based upon the proliferation and low expense of modern GPS.

Don't be such a defeatist, gusgus, its all the little decisions made by people just like you that have created the world we live in, not any President's.

jimh posted 03-19-2012 11:03 AM ET (US)     Profile for jimh  Send Email to jimh     
The analogy to a wired telephone for the LORAN comparison to GPS is not apt. A better analogy would be to say that LORAN and GPS are both wireless telephones. Now we can argue about the clarity of the signal.

By the way, I can usually tell when someone calls my AT&T wired telephone from a modern, digital, VOIP telephone: the voice quality is bad, there is a lot of latency in the connection, and the connection is plagued with drop outs. So much for progress.

I prefer to keep the political speculation out of the discussion. For me, LORAN was a working system, already in place, that offered a low-cost alternative position finding and timing resource, which could have been very inexpensively upgraded.

The next time you read about a launch vehicle failure and a $1-billion GPS spacecraft being lost, think about the couple of million it would have cost to upgrade LORAN.

prj posted 03-19-2012 11:13 AM ET (US)     Profile for prj  Send Email to prj     
On this we concur; progress is not always good, its simply inexorable.
gusgus posted 03-19-2012 12:24 PM ET (US)     Profile for gusgus  Send Email to gusgus     
PRJ said: "Don't be such a defeatist, gusgus, its all the little decisions made by people just like you that have created the world we live in, not any President's."

I am neither a defeatist or pessimist. I am a realist. The difference is largely the facts surfacing daily in America, creating a true concern for my country.

Facts like jimh has reported in this thread are exposed every day and it seems they are all huge issues, like Loran. He brought up a good point, and even if your opinion of these facts are less important to you than they are to other Americans, they should be considered and discussed, long before their destruction.

This dismissal of any discussion is an Obama regime motis operandi, , supported far too often by the public.

LORAN is an old technology that is cheaply modernized as a country security system if our would becomes blinded by GPS aimed attacks. It is less than presidential to destroy any national navigation aid without discussion. Example; what item from the 1900's is mandatory in all aircraft, including jetliners? And why is it mandatory? (slang name) Whiskey Compass.

Plus even the information source "GPS World" supports keeping LORAN, although supports upgrading to eLORAN. read here;

prj posted 03-19-2012 12:48 PM ET (US)     Profile for prj  Send Email to prj     
Opposing the administration's decision to kill the LORAN system is fine, gusgus.

Suggesting that you are a "realist" while harboring an "overwhelming sense that this current administration is H&!! bent on destroying the past successes in almost every area and subject in America" is delusional. Reconcile your published language with your recognition of self.

jimh posted 03-19-2012 07:21 PM ET (US)     Profile for jimh  Send Email to jimh     
You can anticipate that the federal government will spend five-hundred times more money defending itself in lawsuits by the billionaires who backed LIGHTSQUARED than it would have cost to modernize LORAN. Now that LIGHTSQUARED have been shown to be technically irresponsible with their plan to convert satellite allocations into terrestrial allocations adjacent to the GPS L1 carrier, they have announced they intend to seek compensation in the court system. The federal government will waste a billion dollars on lawyers fighting with LIGHTSQUARED. You'd think with the trillions of dollars in the federal budget there could have been a few million for funding LORAN. No, we just get E-15 gasoline and more welfare cheese.
L H G posted 03-19-2012 07:41 PM ET (US)     Profile for L H G    
Is there a difference between what the Government did killing old fashioned Loran, and killing the old fashioned 2-stroke outboard, forcing consumers spend billions on overpriced DFI's and 4-stroke engines? Can we have it both ways?
jimh posted 03-19-2012 07:44 PM ET (US)     Profile for jimh  Send Email to jimh     
Yes--To get the old-fashioned two-cycle high-emission outboard engines back on the market you just need to repeal the Clean Air Act. Write your congressman. The restriction on high-emission outboard engines is a direct result of a vote of congress. Killing off LORAN was a policy decision of the executive branch.
jimh posted 03-19-2012 07:50 PM ET (US)     Profile for jimh  Send Email to jimh     
By the way, although I was doing some offshore boating in the LORAN era, I never made much use of LORAN. LORAN units were always too expensive for my boating budget. Finally, in the late 1980's we got LORAN aboard. However, the device was not a chart plotter, it just gave position fixes. You had to transfer the position fix to the chart with pencil, dividers, and rulers to see where you were.

Learning to navigate without electronic charts and radio-location systems like LORAN and GPS taught me to be a better navigator. We sailed a few thousands miles on just a DR plot and occasional fixes from lines of position on prominent navigation aids. This era of driving around with a big color chart display and your boat position shown with 15-foot accuracy does not really teach navigation to the boat driver.

jimh posted 03-20-2012 08:24 AM ET (US)     Profile for jimh  Send Email to jimh     
There is a good article at Wikipedia about LORAN and its termination. See

jimh posted 02-28-2014 05:27 PM ET (US)     Profile for jimh  Send Email to jimh     
There has been a flurry of news about reviving eLORAN in the USA. It appears that some Congressmen have been alerted to the absurd policy decisions being made by the Obama Administration and its Homeland Security branch, which have been trying to dismantle the existing legacy LORAN stations, towers, and transmitters, and, in the process, spending more money than it would take to upgrade the infrastructure to eLORAN.

See InsideGNSS magazine's article at:

for more details. It mentions an important consideration: preservation of the legacy LORAN transmitter sites, which were located on ground whose electrical conductivity was very good for LF radio transmission. (All legacy LORAN was transmitted at 0.1-MHz using time-division multiple access methods.)

It seems hopeful that Congress will stop the Obama administration from tearing down more towers and selling off the transmitter sites. But you never know what the executive branch of government can do. Just ask the people who had planes at Chicago's Meig's Field. Now there was for a good example of the Chicago School of executive branch action.

In a recent presentation to Congress, an industry expert testified that the cost to rejuvenate LORAN into eLORAN might be only $40,000,000--"That's million with an em," the fellow told Congress. Off-microphone one of the representatives replied, "We don't deal in figures that small."

jimh posted 02-28-2014 08:58 PM ET (US)     Profile for jimh  Send Email to jimh     
About a month ago I read an excellent article on eLORAN in GPSWORLD magazine. It chronicles in detail the many stages of the government of the USA moving, first, toward implementation of eLORAN, and then, inexplicably, withdrawing from eLORAN. While the USA was going about blowing up perfectly useful antenna towers at legacy LORAN sites around our nation, the United Kingdom, Russia, China, South Korea, and Saudi Arabia were moving ahead on implementing eLORAN. See Dana Goward's excellent historical perspective in the January 2014 issue, beginning on page 8. You can read it on-line at

fno posted 02-28-2014 09:03 PM ET (US)     Profile for fno  Send Email to fno     
OK, I admit that I am not old enough to have used Loran myself and only have a small working knowledge of the system. It seems to me that a Loran position fix was only useful to the Loran receiver that made the fix. Exporting that position fix to another Loran or GPS via Lat-Lon has been reported many times to be inaccurate. I may be wrong and admit limited knowledge. I do have one question though. If Loran is that good that it should be kept around, why is GPS the go to for ground surveying. I realize that for surveying, the GPS needs to be augmented with a few ground stations for accuracies sub meter but this does not answer why Loran or ELoran could not continue to perform some of these tasks. If Loran is that good, the commercial market should be running with it. Is it relative to the fact that everyone seems to expect our electronic navigation information to be provided by our government? It makes sense to remember that Loran and GPS are both systems developed by the military for their own purposes and that the general public is able to benefit from these signals by virtue that commercial interests convinced the military to share the information. Good choices or bad choices by our government over the years does not negate the fact that reception of these navigational signals is not an entitlement. If in fact there is a military or political conflict that forces a shift and or shut down of the GPS grid, input from commercial and public interests will have very little say in the matter.
jimh posted 02-28-2014 09:27 PM ET (US)     Profile for jimh  Send Email to jimh     
The range location methods of LORAN and GPS are the same methods. When LORAN is updated to 2014 technology or eLORAN, the positioning data is much more accurate than the LORAN of 1960. Please remember that 1960 was over 50-years ago, and it is not reasonable to continue to think of LORAN technology as being limited to what could be made affordably in 1960.

As one observer has noted, GPS is no longer a range location system but really a fundamental component of modern life, like having running water. An interruption or outage of GPS that lasts more than a few minutes would affect the entire nation in many ways other than having your recreational chart plotter lose its position data.

I think if you read the several articles I have linked (above) you will gain a better understanding than I could impart by trying to repeat them to you. I also recommend you ignore uninformed comments from people completely out of touch with the technology.

jimh posted 03-01-2014 10:30 AM ET (US)     Profile for jimh  Send Email to jimh     
There are some interesting exchanges between the Congress and USCG regarding LORAN in a recent committee hearing of the House Committee on Transportation and Infrastructure that took place on February 4, 2014. The topic of the hearing was "Finding Your Way: The Future of Federal Aids to Navigation."

Mr. Dana Goward gave interesting testimony which can be seen in a recording of the hearing available at

Scrub forward in the recording to one-hour 33-minutes, when the panel reconvenes for its second session. In his opening remarks, Mr. Goward says, "And let me say, right off, mister chairman, are welcome to any of our meetings, any time.... Unlike the government, we are very open."

This remark is probably in reference to earlier testimony by a USCG rear admiral. When the panel asked the rear admiral about eLORAN, the rear admiral declined to answer in the open hearing, and cited concerns about those present possessing the necessary security clearance to have access to information about eLORAN or its status.

jimh posted 03-01-2014 10:32 AM ET (US)     Profile for jimh  Send Email to jimh     
Mr. Goward's written testimony can be read at

fno posted 03-03-2014 09:15 AM ET (US)     Profile for fno  Send Email to fno     
As Jimh implies, I am completely out of touch with the technology. So please ignore my uninformed comments as he suggested. Given my very limited experience with Loran from only trying to understand the functionality of later model recievers and giving up. I can only say that even the most rudimentary early generation GPS is(was) easier to use, as accurate, and allows more quality boating time that would otherwise be wasted reading the pointless LCD(gas tube) numbers and transposing them to a paper chart. I also agree that given the scope of GPS usage that a backup system is needed. I just hope that backup system will be as user friendly as a modern GPS. Perhaps Jimh can provide us with an example of a user friendly Loran receiver.
jimh posted 03-03-2014 09:37 AM ET (US)     Profile for jimh  Send Email to jimh     
fno--you should consider that the present day boat electronics which show your position on an electronic chart have nothing to do with either LORAN or GPS. Showing your position on an electronic chart is a way of presenting your position information to you. It is not a part of the method of finding the position from a navigation system.

A modern position locating receiver using eLORAN can provide an output of position in latitude and longitude coordinates, in precisely the same manner that a GPS receiver can. That position can be presented on an electronic chart display.

The accuracy of the position determined from a modern eLORAN receiver is suggested to be comparable to the accuracy of the position from an unaugmented GPS receiver solution. The accuracy of both systems, eLORAN and GPS, can be improved by separate augmentation systems. In the case of GPS, there are two augmentation systems which are operated as separate systems, the differential GPS system (DGPS) of the Coast Guard and the wide-area augmentation system (WAAS) of the Federal Aviation Administration. Similar augmentation systems could be employed to improve the accuracy of eLORAN, using similar methods to compensate for the similar problems. In both GPS and eLORAN there are inaccuracies introduced due to variations in the speed of propagation of the radio signals. Similar methods can be used to compensate in real time for these variations.

Perhaps you have forgotten that the accuracy of a GPS position fix was being intentionally degraded by use of Selective Availability (SA), and it was only in c.1996 that SA was ordered to be turned off, allowing civilian users of GPS to have improved precision in their position solutions. The appearance of the FAA's WAAS system is also fairly recent in GPS history. The WAAS augmentation became available initially in c.2003.

The combination of removal of SA and introduction of WAAS has upgraded GPS position fix accuracy significantly, and we now enjoy the benefit.

An eLORAN system of modern design should be able to provide position information of comparable accuracy, but there are other elements of eLORAN which are also important to understand. eLORAN can provide its signal to locations where GPS can never reach, such as inside of buildings. There is also much greater immunity to interruption of service from eLORAN because of the nature of its signals.

jimh posted 03-03-2014 10:14 AM ET (US)     Profile for jimh  Send Email to jimh     
I also suggest readers be mindful of the relative costs of providing the navigation services of GPS or eLORAN. It is said that the cost to put eLORAN into operation today would be about $40-million. I think that the rocket that launched the latest billion-dollar GPS satellite, one of 32 needed to be maintained in orbit, probably consumed that much cost in rocket fuel during rocket engine burn. And the entire $170-million rocket is a disposable cost. Maintaining a Cape Canaveral launch facility cost billions of dollar each year.

As the TOPIC line suggests, there is something absurd going on with the government and its reluctance to invest in eLORAN as a back-up to GPS. There is even a willingness by a public non-profit to share the costs with the government to get eLORAN started.

kglinz posted 03-03-2014 11:07 AM ET (US)     Profile for kglinz  Send Email to kglinz     
How about this theory. Loran or any other inexpensive system, be it aircraft, tanks, or electronics will not be built, because there isn't enough money in it to "buy" the congressman needed to authorize it.
jimh posted 03-03-2014 05:14 PM ET (US)     Profile for jimh  Send Email to jimh     
I like the theory. The situation certainly smells very political. The industry people that write about it seem to handle the politics with extremely careful statements, too. It is the elephant in the room.
dfmcintyre posted 03-03-2014 08:46 PM ET (US)     Profile for dfmcintyre  Send Email to dfmcintyre     

You were probably using or looking at one of the early loran units that gave location information in TD (time differentials?) and there were TD lines on a chart. Sitex was an early brand, that I used, or attempted to use.

By the late 80's, early 90's, enough computing power was available to allow companies to develop units that made the conversion to L/L automatic.

I think my unit was a Northstar. It had repeatable accuracy of about 150'. I define repeatable accuracy as sitting at a dock, stable and not moving, noting the L/L and then attempting to return to the same location and noting just how close I could get.

Regards - Don

fno posted 03-03-2014 10:17 PM ET (US)     Profile for fno  Send Email to fno     
Thanks Don, I am just playing the devils advocate here. I did in fact see, not play with a few Loran units that came up with Lat/Lon fixes. I also believe that Jim is correct in saying that using todays or tomorrows technology, eLoran can be as good if not better than GPS. That Northstar of yours would be great for finding a Starbucks or Dunkin Donuts as there seem to be two on every intersection. Finding a wreck or rockpile with a slew of grouper and red snapper is another story, especially when you have to line up an anchor point several hundred feet upwind and up current to the actual spot and hope that the fix stays true. While I agree with many of Jimh's assertations and quotes here, I find his opinion of blaming the government and less importantly President Obama for the demise of Loran lacking in substance. More of a political pot stirring adventure conjured up by 3 feet of snow outside and a fridge full of IPA. Jim has probably forgotten more about this technology than most of us can work with and deserves credit for explaining most of it to us. My opinion is that Loran and it's commercial and technical development for use by the general public, industry, agriculture, aviation, nautical, and government interests never got off the ground because for fifty years it was just a bunch of numbers on the front of a box. GPS would have suffered the same fate had there not been the technology to put the numbers to a screen with a map on it.
AZdave posted 03-04-2014 01:59 AM ET (US)     Profile for AZdave  Send Email to AZdave     
I went online to find a loran receiver. I searched Google and a couple of large retail sites. I can find GPS units that will report position in loran format to allow use of older position data, but I can't find an actual receiver. Did the manufacturing and retail sectors give up on this before the government?
jimh posted 03-04-2014 11:05 AM ET (US)     Profile for jimh  Send Email to jimh     
I don't think there is much of a market in the USA at the moment for a LORAN-C receiver. The USCG shut off LORAN-C a few years ago.

I have not made a survey of eLORAN receivers. I expect there are eLORAN receivers on the market, but they are aimed at commercial ships. I expect they are much more expensive than GNSS receivers.

The retail cost of a GNSS receiver is now down to the under $30 price range. There is a GNSS receiver in just about every smartphone on the market. I do not expect that eLORAN receivers will ever get to a price as low, nor will they become so compact they fit on a smartphone.

Re the politics: the change in direction of the government re eLORAN occurred coincident with the change in Executive Branch leadership. When the government takes a 180-degree turn in policy, I think it is more likely that change came from a top-down direction than from a bottom-up. For example, I don't think a bio-chemist in Ann Arbor decided to initiate a government policy on auto emission.

From what I can gather, I don't hold the Coast Guard culpable. They basically said something like this: Hey, we are spending some of our budget to run this LORAN operation, and we do not use it any more. Then the Executive Branch (pre-Obama) said, OK, announce that formally, and we'll let these other guys who want to run it and make it eLORAN take over. The Coast Guard did their part. They said they don't use it, and let us save our budget for some other stuff. The problem came when no funding was provided for another agency to take over and carry forward on the eLORAN.

I don't know that there was malice in the Obama administration neglecting to continue the eLORAN. Perhaps it was just an oversight or neglect. When they came into the Executive Branch, I am sure eLORAN was not on their agenda. When there was no budget for it, the progress stopped.

The absurd aspect is the cost of blowing up towers, removing them, clearing the land, and disposing of the property and equipment is reported to be higher than the cost of completing the eLORAN transition.

AZdave posted 03-04-2014 02:29 PM ET (US)     Profile for AZdave  Send Email to AZdave     
It looks like there was a lot of effort to terminate loran well before the change in administration. Maybe the politicos that refused to let it die had installations in their home districts --but that's a cynical view. My boat is hooked up and I'm off to navigate with my Mark 1 eyeballs. 2006-12-08/congress-blocks-loran-turnoff

jimh posted 03-04-2014 11:15 PM ET (US)     Profile for jimh  Send Email to jimh     
Thanks for the link to that article. It has a lot of good information I have not seen before. For example, I had no idea that all the LORAN stations in the lower-48 had already been upgraded. What a waste!

I think the USCG has been trying to get out of the LORAN business for some time. The people that want eLORAN really want it as a back-up for navigation and as an alternative source of timing signals.

ASIDE on timing signals:

Since 1976 I have worked in an industry that needed very consistent time keeping. In our plant we had two master clocks that ran on crystal controlled time bases that were kept in a thermostatically regulated oven. We operated these like an old ship operated its chronometer: we never tried to adjust their setting. Pulses from one of these two master clocks drove all the secondary clocks in the plant. There were about 20 secondary clocks. We needed all the clocks to be in unison and to be accurate.

Our external-to-house primary time standard was the Naval Observatory in Washington, D.C. We set the secondary clocks to match that time. Back in the days when all telephones were on landlines, we would make a telephone call to the Naval Observatory. They have a telephone line that answers and lets you hear the time being announced with clicks. It is like listening to WWV on a radio. Over many years the master clocks would drift off from the external-to-house primary standard. We never reset them. We just used the pulses.

We would set all our secondary clock to the time from the Naval Observatory. We could easily add drop one second from all our secondary clock, add one second, or also jog the secondary clocks one hour plus or minus for daylight savings time, by using a little control panel on the master clocks. To lose time, it would just stop its output pulses for one second or one hour. To gain time, it would speed up its pulses to double the rate for the necessary interval.

A few years ago, the plant abandoned the old crystal-oven controlled master clocks, and replaced their pulses with precise one-second pulses from a GPS receiver. So now all of the time keeping in the plant depends on a GPS receiver on the roof of the plant which must receive signals from orbiting satellites to maintain its accuracy. The antenna is on the roof of a building in a downtown urban environment. If some guy in an apartment building on the next block in line-of-sight of that GPS antenna buys himself a GPS jammer, there could be a problem for the master clock pulses.

Hoosier posted 03-08-2014 10:39 AM ET (US)     Profile for Hoosier  Send Email to Hoosier     
I would think that your "plant" would use an "atomic clock" that synchs to WWV's radio time signal rather than GPS, since the GPS time signal is vulnerable to not only jamming, but interruptions due to space weather.
jimh posted 03-08-2014 01:23 PM ET (US)     Profile for jimh  Send Email to jimh     
We needed the 1-Hz pulse to run the 50-year-old FAVAG clocks. I don't know of any inexpensive atomic clocks that output the 1-Hz pulse needed.

Image of a FAVAG 1-Hz pulse secondary clock:

FAVAG has a rich history in keeping time with electrical pulses. See

Horloges électriques (electric clocks)

Since they were Swiss-made, the clocks are rather durable and long lasting. Plus, a dial face clock with an accurate second hand is very handy in many timing situations. Better than a digital clock display.

There several specialized GPS receivers that provide a 1-Hz pulse output which is synchronized to the GPS time that is regulated with Cesium or atomic clocks.

Also note that GPS keeps its own time, different from UTC. We just use the pulses from the GPS receiver. But, as was my point in mentioning this, if the GPS constellation is not available, these secondary clocks and probably many others, will lose their primary clock reference.

It is also something of pain to have to mount the GPS receiver up on the roof and run its signals via about 400-feet of cable to the FAVAG clock system. It would be simpler to install an eLORAN receiver in the rack next to the FAVAG clock, and the eLORAN would probably be able to receive the reference stations inside the building without much trouble. As you know, 0.1-MHz radio signals will propagate inside a building without much loss. As for WWV, it is hard to receive indoors. It is much farther away (Colorado) than eLORAN would be (Dana, Indiana), and subject to ionospheric diurnal variation. But, don't blame me, another guy engineered the GPS clock system.

fno posted 03-09-2014 05:35 PM ET (US)     Profile for fno  Send Email to fno     
Jim, how accurate is the GPS clock system? I have used it for years to reset the time by 5 minutes a week on my crappy Swiss Omega chronometer that cost a small fortune.
jimh posted 03-09-2014 09:01 PM ET (US)     Profile for jimh  Send Email to jimh     
If you are really synchronized to GPS, your time is as accurate as their cesium atomic clocks. The time is accurate to a very high precision. UTC time is corrected by leap seconds periodically. I wrote an article on the nature of GPS time earlier. See

Solar Time, Universal Coordinated Time, and GPS Time

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