TomD wrote:Oops, mis-spoke. Utah only received $1.27 per $1.00 Tax paid. I was looking at the wrong table.

Hey Tom,
how about posting the stats on the rest of the west.

Lets put in for a grant to study aerial road signs. We'll need a bunch even-thousands and odd-thousands poles, and procedure to correlate the facing direction of the signs to the poles. $40M should be a good start...

Zane,

Selective Availability is the capability that the US military has to introduce a dither into the GPS systems such that, unless you have a receiver capable of decoding the dither, your position accuracy is degraded.

I flew airplanes with GPS for a couple years with SA engaged, and never complained a whit. Worst case scenario, the thing would give me a 50 yard error. Who cares? Hell, even with SA engaged, you could dang near fly a precision approach with GPS.

I believe the Russians also have a GPS system operational at the moment. Nobody's turning off GPS in the near future, cause UPS, FedEx, the train system and trucking system in this country would fall flat on its ass if they did. Aviators are NOT the power users of GPS.

MTV

The greatest danger to the GPS satellites is a solar flare. The biggest one in recorded history was in 1859, and it caused failure of telegraph systems on the ground. Satellites are very vulnerable to these storms. However, the only one of note was in March 1989, and it was much smaller than the event of 1859. All of the GPS satellites went up after the 1989 solar flare. Many people who rely on GPS don't seem to be aware of this vulnerability.

I'm not defending or promoting LORAN, but there needs to be a backup plan.

Heres an interesting article out of Aviation Today.




Monday, May 18, 2009

Battle Brewing Over Loran; Overnight, Colgan News
Ramon Lopez
U.S. lawmakers and industry experts are critical of President Obama’s plan to shut down a decades-old navigation system that could serve as a backup to the Global Positioning System (GPS), the backbone of the Federal Aviation Administration’s Next Generation Air Transportation System (NextGen).

At issue is the reliability, availability and vulnerability of the in-service GPS satellite constellation, which is already being used to provide air traffic navigation in remote locations, pinpoint targets for precision guided munitions and guide hikers and drivers to their destinations. Also under debate is what existing navigation system is needed to supplement GPS, if any.

President Obama’s 2010 federal budget proposes to cut all funding for the Loran-C navigational system, shaving $35 million in 2010 and $190 million over five years.

Loran-C consists of a chain of 24 land-based, low frequency radio transmitters in the continental United States that send out precise times and coordinated signals. It provides navigation, location and timing services for both civil and military air, land and marine users. It currently serves as a supplemental air navigation system.

Obama called for the cancellation of the program despite the Department of Homeland Security’s (DHS) endorsement of a plan to upgrade the Loran-C system as a backup to GPS. The new system would be known as eLoran.

In February 2008, DHS announced its support for eLoran as an independent national positioning, navigation and timing system that would complements GPS in the event of an outage or disruption in service.

It said “eLoran will mitigate any safety, security, or economic effects of a GPS outage or disruption. eLoran system will be an enhanced and modernized version of Loran-C, long used by mariners and aviators and originally developed for civil marine use in coastal areas. In addition to providing backup coverage, the signal strength and penetration capability of eLoran will provide support to first responders and other operators in environments that GPS cannot support, such as under heavy foliage, in some underground areas, and in dense high-rise structures. The system will use modernized transmitting stations and an upgraded network.”

The Obama administration is proposing to terminate the long-range radio navigation system operated by the U.S. Coast Guard, saying it is “obsolete” technology. “Loran-C is a federally-provided radio navigation system for civil marine use in U.S. coastal areas. The Nation no longer needs this system because the federally-supported civilian Global Positioning System (GPS) has replaced it with superior capabilities. As a result, Loran-C, including recent limited technological enhancements, serves only the remaining small group of long-time users. It no longer serves any governmental function and it is not capable as a backup for GPS,” the Office of Management and Budget (OMB) stated.

“Several federal agencies, including the Departments of Defense, Transportation, and Homeland Security, already have backup systems for their critical GPS applications and the termination of Loran-C does not foreclose future development of a national backup system. It merely stops the outflow of taxpayer dollars to sustain a system that does not now and will not, in its current state, serve as a backup to GPS,” the OMB added.

Senator Jay Rockefeller (D-WV) chairman of the Committee on Commerce, Science and Transportation, advocates continuing the Loran system, saying it is the best backup to GPS. Rockefeller sees “the need to maintain Loran-C while transitioning to enhanced Loran as a means to enhance the homeland security, marine safety and environmental protection missions of the Coast Guard.”

Senator Susan Collins (R-Maine) says” “discontinuing the entire program would leave the nation without a backup to the GPS program, wasting millions of dollars already spent on this system.” To bolster her case, Collins cited a new General Accountability Office (GAO) study that warns that delays in launching new GPS satellites could imperil the performance of the navigational system.

“It is uncertain whether the Air Force will be able to acquire new satellites in time to maintain current GPS service without interruption. If not, some military operations and some civilian users could be adversely affected,” the GAO report has concluded.

It said: “The USAF has struggled to successfully build GPS satellites within cost and schedule goals; it encountered significant technical problems that still threaten its delivery schedule; and it struggled with a different contractor. As a result, the current IIF satellite program has overrun its original cost estimate by about $870 million and the launch of its first satellite has been delayed to November 2009--almost three years late. “

Furthermore, “while the Air Force is structuring the new GPS IIIA program to prevent mistakes made on the IIF program, the Air Force is aiming to deploy the next generation of GPS satellites three years faster than the IIF satellites. GAO's analysis found that this schedule is optimistic, given the program's late start, past trends in space acquisitions, and challenges facing the new contractor. Of particular concern is leadership for GPS acquisition, as GAO and other studies have found the lack of a single point of authority for space programs and frequent turnover in program managers have hampered requirements setting, funding stability, and resource allocation,” the GAO report added.

“If the Air Force does not meet its schedule goals for development of GPS IIIA satellites, there will be an increased likelihood that in 2010, as old satellites begin to fail, the overall GPS constellation will fall below the number of satellites required to provide the level of GPS service that the U.S. government commits to,” the GAO has concluded.

A study requested by the Department of Transportation (DOT) in August 2006 and completed in March 2007 by an Independent Assessment Team (IAT) commissioned by the Institute of Defense Analyses (IDA) and publically released in January 2009 recommended that the U.S. Government complete the eLoran upgrade and commit to eLoran as the national backup system to GPS for the next 20 years. Based on the IAT report, DOT and the Department of Homeland Security (DHS) jointly recommended that eLoran be the national backup for GPS.

The IAT maintains that “eLoran is the only cost-effective backup for national needs; it is completely interoperable with and independent of GPS, with different propagation and failure mechanisms. ... It is a seamless backup, and its use will deter threats to U.S. national and economic security by disrupting (jamming) GPS reception.”

It is unclear whether the fiscal 2010 budget proposal actually zeros out funding for eLoran and DHS may end up a key player in keeping eLoran alive. DHS plans to complete a review of GPS backup systems in June.

mtv wrote:Zane,

Selective Availability is the capability that the US military has to introduce a dither into the GPS systems such that, unless you have a receiver capable of decoding the dither, your position accuracy is degraded.

I flew airplanes with GPS for a couple years with SA engaged, and never complained a whit. Worst case scenario, the thing would give me a 50 yard error. Who cares? Hell, even with SA engaged, you could dang near fly a precision approach with GPS.

MTV

Correct me if I'm wrong, but SA was continuously in effect up until, what, seven or eight years ago? I used GPS in the '90's both for wildlife surveys and also for trail mapping. The deal was that you took your position data as displayed on the GPS, and then 24 hours later you could get the dither values and correct all your positions.

Hey Tom,
how about posting the stats on the rest of the west.

Here you go, but you are not going to like the what happened to Oregon, and you did not even get kissed.

http://www.nationalpriorities.org/publi ... te_in_2005

These are the latest stats available as far as I can tell.

With the shift in control of Congress I am sure some of the funding will shift towards the party in control.

TD

DP,

Actually, working for the govmint, we got PLGR's from the military, which resolved the dither. Point is, even with SA turned on, the accuracy of GPS is FAR better than LORAN ever was, or ever will be.

The thing I hated about LORAN is that the dang thing will lie to you, and tell you you're thirty miles from where you actually are. GPS won't lie to you. It may tell you it can't figure out a location, but it won't lie to you.

Airlines for the most part used GNS or INS prior to GPS. That system, which has nothing to do with ANY government system, would be the likely fall back if GPS went belly up.

Folks, please, someone here post a picture of a LORAN unit mounted in an airline cockpit for me????

Thanks, I'll be waiting for that "backup" to become apparent.

MTV

Wow, you guys have been busy here today! I don't think anyone is arguing with the fact that GPS is a superior system. The question is, Do we need a backup for GPS and if so what would it be?

The loran system is CHEAP compared to any other forms of navigation and are already in place. Most of the transmitters have already been upgraded to eloran and they DO work with the existing equipment.

Here is a good article.

By Bob Brewin 06/12/09 05:09 pm ET

The Obama administration came up with a loopy plan to save a grand total of $36 million out of the proposed $3.5 trillion federal budget by canceling funding for the Coast-Guard-operated terrestrial Long Range Navigation system (Loran). A lot of folks (except the bean counters) view Loran as the only viable backup to the satellite based GPS system used for position, navigation and timing worldwide.

The Senate Committee on Commerce, Science, and Transportation thinks otherwise, and came up with $37 million in fiscal 2010 and fiscal 2011 in its version of the Coast Guard's 2010 authorization bill to operate the Loran system, as well as an upgrade to a more precise system called enhanced Loran (eLoran).

The Coast Guard operates 24 Loran stations nationwide and 19 stations have been upgraded to eLoran, which broadcasts a data channel to improve accuracy, availability and integrity of geospatial information.

eLoran provides position accuracy to between 8 feet and 65 feet, with availability measured at 99.9 percent and integrity at 99.99 percent, according to the International Loran Association. GPS offers position accuracy between 8 feet and 25 feet for civilian users, but its high-frequency, low-power signal can be jammed more easily than the low-frequency, high-power eLoran signals.

GPS was developed by the Defense Department for its precise navigation and location requirements in the 1970s, and since then it has morphed into a global utility used as the base technology for the Federal Aviation Administration's air traffic control system and its timing signals are used by telecommunications companies worldwide for network synchronization.

GPS faces more down-to-earth problems than jamming. The Government Accountability Office reported last month that GPS performance could start to degrade next year. Delays in the development and launch of two GPS satellites could reduce the number of satellites in orbit to below the minimum 24 that are needed to provide precise location information, GAO said.

Cristina Chaplain, director of acquisition and sourcing management at GAO, told a House hearing last month that if the number of GPS satellites drops below 24 it could have a heavy impact on users, including intercontinental commercial aviation, which "may have to cancel, delay or reroute flights." Cell phone enhanced 911 emergency services, which rely on GPS to locate callers, "could lose accuracy, particularly when operating in urban canyons or mountainous terrain," she added.

So, what's the problem in spending $37 million a year on an eLoran backup?

mtv wrote:... GPS won't lie to you. It may tell you it can't figure out a location, but it won't lie to you. ...

I hate to be the bearer of bad news, but GPS WILL LIE TO YOU! Fortunately, it tends to be little lies, however, I had one that was a whopper.

I was down in Hell's canyon (VERY deep canyon, for those who don't know it) and it told me I was over in the Salmon River canyon, several miles away! Astonished, I cycled the power and the problem didn't clear. I then discovered that there were no satellites overhead, and the ones it was picking up were blocked by the canyon walls. I was receiving the signal after it was reflected off of the canyon walls!

That condition is often referred to as multi-path error. I researched it a bit after that incident, and discovered that there is another source of errors due to the ionosphere. The radio waves are slowed by the ionosphere, and the receivers have to fudge the numbers to account for that. However, the ionosphere varies in size, but the receivers only use an average value. So, there can be a varying level of error here, but it is my belief that it is not very significant most of the time. If anyone has any boundary information on worst-case scenarios for ionosphere errors, I'd be interested in knowing it.

You can have multipath errors where the signal is line-of-sight, and reflected at the same time, and there can be situations where the reflected signal is stronger than the true signal. It happens all of the time in cities with tall buildings. Who knows, it might happen if you fly past a mountain with a parabolic shaped glacier!

In the navy (1968) we had loran C sharts. We would tune in the signal and to get a reading, then draw a line on the chart. Tune in another and draw another line. Very acurate if the lines on the chart were close together. The farther apart the line were, the less accuate.

One time when in the sea of Othoska, I did a loran C fix and it put us 55 nautical mile inland. I knew we were not there cus we were still rockin.

In the right area, loran A worked pretty well. A good celstial fix and an acurate hand dr was what we relied on for the most part. You could not rely on the Rusian light houses cus they would change the lights just to piss us off.

Tim

Again, show me a LORAN receiver in an airline cockpit. NO system is going to serve as a backup if it isn't installed AND approved for navigation by the FAA. So, can you fly instrument approaches with LORAN?? No. Would that ever happen? Only after an agonizingly long test period, and only if LORAN turned out to be a lot more reliable than it has been in past. So, where's the backup?? At altitude, VOR's reach out to a hundred miles or so, assuming no terrain problems. That system is still functional. The FAA would like to shut down the VOR system, so they could save some money in THEIR budget, and call LORAN the "backup" system, paid for out of the CG budget. Meanwhile, the FAA closes down VORs and Radars (that is what "NexGen proposes, by the way) and keeps all that money for other things, like parties, maybe.

LORAN is not a viable alternative to GPS. LORAN was designed as a system to help SHIPS navigate, it's not a terrestrial navigation system. Note that the only stations inland are designed to cover the Great Lakes.

So, GPS goes belly up.....for whatever reason, maybe the AF doesn't pay the power bills. Aviation is going to just STOP while every airliner (and UPS truck and....) is retrofitted with a 25 year old POS LORAN receiver???? That they aren't permitted by FAA regs to actually use for navigation??? Uh, does anyone see a basic flaw in this logic but me??

Yeah, man, I'd hang onto those old beater LORAN units, waiting for United to come knocking. I'll bet they'll pay one hell of a price for that sucker when the GPS system goes down the tubes.

MTV

kevbert wrote:

mtv wrote:... GPS won't lie to you. It may tell you it can't figure out a location, but it won't lie to you. ...

I hate to be the bearer of bad news, but GPS WILL LIE TO YOU! . . .

I was down in Hell's canyon (VERY deep canyon, for those who don't know it) . . . I was receiving the signal after it was reflected off of the canyon walls!

You can have multipath errors where the signal is line-of-sight, and reflected at the same time . . . It happens all of the time in cities with tall buildings. Who knows, it might happen if you fly past a mountain with a parabolic shaped glacier!

A couple of thoughts:
If I'm flying in a city "with tall buildings" or in "VERY deep canyon" I doubt I'll be spending much time looking at the GPS. If the GPS happens to give me an erroneous reading I probably won't notice, since I'll be more focused on getting my butt safely out of town or said "VERY deep canyon." [I acknowledge that your observation could be relevant to forum members who explore deep canyons by foot or motor vehicle!]

The multipath error problem is an interesting issue, and if you come up with any solid evidence that it has occurred in an aviation setting please pass along the links to the papers or studies that you find. When I think of a parabolic-shaped glacier and it's potential to cause a GPS error - well, I can picture how that might happen in theory, but when you take into consideration variables like signal strength, number of satellites, focal point of the reflected signals, etc, etc, etc, it seems like the probability is infinitesimal. Thanks, though, for pointing out the potential problem; it's something I'll consider if my GPS starts misbehaving.

Back to Loran: as was pointed out earlier, the Federal Government has been working to phase out Loran for years, and the topic has been covered extensively in a number of aviation-related journals and web sites. It's hard to imagine how this could come as a surprise to anyone, but apparently it has. I find Aviation Week, Aviation International News, and AOPA Pilot to be good publications for staying abreast of issues that affect GA pilots. All of these publications have web sites, and their free content always includes the issues that are important to us. If, in spite of all the press the Loran shutdown has recieved you've just spent money to install a Loran, you may want to save yourself some money and aggravation by reading the back issues of these magazines. Five years worth should probably cover the important topics that you've missed.

You missed an imortant point MTV. Typical of an ST. Now you got to listen to a QM here. Loran would be a pretty good backup for those flying VFR that either forgot how to or are just too lazy to get out a chart, draw a line, use an E6B, tune in a VOR and draw a line of position and do a hand DR. Need I go on MTV.

Tim

Here ya go, straight to Hot Air...

Can't you dumb Squids just get along?!?!?

Gump

GumpAir wrote:Here ya go, straight to Hot Air...

Can't you dumb Squids just get along?!?!?

Gump

Least we are not sea going bell hops.

Tim

qmdv wrote: Loran would be a pretty good backup for those flying VFR that either forgot how to or are just too lazy to get out a chart, draw a line, use an E6B, tune in a VOR and draw a line of position and do a hand DR.

Tim

Hate to admit, but I'm one of the lazy ones! I know how to read a chart and pretty good at finding my way with landmarks, but that damn E6B??? Eerrrr!! And what the hell is VOR??? I don't even have a VOR in my plane! Got it on the 396, though. Oh.....and what is "do a hand DR"??

I'm sorry if I pissed you guys off so much by putting a Loran in my plane. PA12, Your right, here has been talk of Phasing out both Loran and VOR,s for years. I did quite a bit of reading on the lorans before I decide to use it.

There are also lots of articles stating that the Loran System would never be shut down if for no other reason that costs "peanuts" compared to other forms of navagation equipment. I agree that the Loran C System left a lot to be desired but in the last few years the Government has been upgrading the Loran to the "Enhanced Loran" or eLoran. That system is almost as accurate as a GPS without WAAS. Plus it is already in and functional.

I did do my research and thought it was a good cheap way to go for a backup system. My friend that was a Pilot for Air America told me that is all they used and he loved it. He thinks it is a huge mistake to shut it down. The guy at King's Avionics that made the harness for the CDI told me his family had a 618c in their plane and loved it. There is a guy on Pilots of America's forum that uses his every time he flies.

MTV, the Loran System was used sucessfully in WWll and popular until the Civilian GPS system was finished. The first GPS satellite was launched in 1989, and the 24th and last satellite was launched in 1994. I don't think I would consider 50 years of successful use a "flash in the pan" GPS and Loran use the same technology, signal timing and triangulation of the signals. The Loran signal will go over a thousand miles. Does your VOR?

In my first computer class we typed our programs on a card punch machine and then took the cards and fed them into a computer the size of a room. Our assignment was to figure out how much money you would have if you invested $1000 @10% on Jan 1 0AD. There were about 3 inches of computer cards to run this program. I got an A because for some reason my program was sent to Logan and run on the University's computer and then sent back to UTC' computer. Don't have a clue why it did that. I also have a GPS from the 90's around here somewhere. It tells you the Latitude and longitude, then you pull out the map and see where you are. My point is, you guys are comparing a primitive Loran to a modern GPS.

My 618c is one of the last ones made. It is a 94 model and database. It has closest airport function, waypoints, current position and just about everything a GPS has except it isn't as user friendly. Plus you CAN buy moving map units. Such as the Apollo 360 and the Argus 7000. The Apollo 360's fit into an instrument hole and are available as either just the moving map for use with a loran or gps reciever or a complete reciever system. I didn't want an old moving map since I have two GPS's so I went with a CDI.

I am not telling you guys you have to use you lorans, but I don't like being told I can't use mine. I think it is a mistake to disassemble a economical, fully functioning system so that we can rely soley on the short range, line of sight VOR's as the only backup. Bottom line of why it is being shut down is stated in the article that Trent posted, "It no longer serves any governmental function". This administration has never demonstrated any common sense before, why would they start now.

Jerry

Jerry,

Get your facts straight. LORAN C, which is the system now in use has NOT been in use since WWII. In fact, LORAN A was barely coming into use at the very end of WWII. LORAN A was a line of sight system. As Tim pointed out, LORAN C, until the early 1980's, relied on the process that he described: Tune three signals, plot those lines on a very large chart, etc, etc. In the late 70's or early 80's, the first "automatic" LORAN receivers came into use.

I hate to break this to you, but when I refer to a "backup to GPS", one guy in AZ isn't exactly the user group I would worry about. In fact, General Aviation is of little concern in this regard, since we are NOT the power users of any navigation system. The power users are the airlines, and as I pointed out, I doubt you'll find ANY LORAN receiver installed in an airline cockpit. In fact, none are available, and none are approved for that use.

The other big problem with LORAN suffers from is geometry. If you navigate along a baseline extension, or are in an area of marginal coverage (and I've lived and flown commercially in both) the system is useless. If you are flying fairly close to one of the stations, the geometry of the signal may not be much good, and your position accuracy will suffer as a result. I doubt that "enhanced" LORAN can fix that, since the system relies on geometry. As does GPS, but GPS is based on satellites, and if you get too close to one of those in your Cessna, you've probably got other issues to worry about. From Fairbanks to the north, LORAN was useless. In Kodiak, you're in a baseline extension, and close to one of the stations, which is on Kodiak. Those are two relatively small areas, but there are many dozens of those kinds of problems, everywhere the system is available. Oh, yeah: There is no LORAN system in the rest of the world....so, the airlines are going to adopt this system???

Jerry, trust me---I could care less if you install and use a LORAN receiver in your airplane. More power to you if you do. I am NOT trying to dissuade you. My concern is that it requires a LOT of taxpayer's (and I am one of those) dollars to support that system. The cost estimates to run that system you've offered are way low, frankly, and doubtless come from folks who have a vested interest in keeping the system operating.

As I said initially, wait till you get some experience NAVIGATING with a LORAN, then get back to us. Oh, and don't just use it to navigate around close to home, cause that's an easy problem.

As to all the LORAN navigator options you list, they are all old, and no longer in production. From the International Loran Association: "We don't know of any aviation Loran-C receivers being manufactured. There is one marine receiver on the market, and it is a good one:

http://www.furuno.co.jp/english/pdf/LC90MK2.pdf "

So, on the NEW market, there is ONE LORAN receiver out there, and it is not tso'd, so isn't going to be installed in an airplane.

Yep, GREAT backup system, for aviation in the US. Frankly, the technology now is such that Inertial navigation is probably a much better solution as a back up than any other. That's how those magic glass cockpits know you're right side up.

I sincerely hope that you love your newly installed LORAN unit, and that it works well for you. Right up until the government pulls the plug on the LORAN system, which I sincerely hope they do real soon.

MTV

MTV, I never said Loran C was used since WWII. Here is a map showing Loran coverage. Others use it too not just us. I just got off the phone with my brother. He flew C 141's and C5's for the Air Force. He said that loran was the primary mode of navigation and all Air Force planes used them until GPS. Why would you think an Airliner couldn't use it?

Why is it that it is always Government Employees that I end up arguing with? Anyway, I see your as hard headed and opinionated as I am. Have a nice day!

http://www.loran.org/images/worldcoverage.jpg