WWV / WWVH Petition

[Dehler 25]

At the very least they could have mothballed the Loran system, it was in place, paid for and a nationwide independent of GPS back up.

[ArmyDaveNY]

Originally Posted by Dehler 25

At the very least they could have mothballed the Loran system, it was in place, paid for and a nationwide independent of GPS back up.

There is good news with regards to Loran. There is a an upgraded version called e-Loran that is in the works. Although it is an upgraded version, it can still be received with the older Loran-C receiver.


Here is a brief but good write up on it;
eLoran | UrsaNav


Additionally, Congress passed H.R. 5769, the Howard Coble Coast Guard and Maritime Transportation Act of 2014 and it was signed into law. This directs the Coast Guard to cease dismantling the Loran system and to encourage all government agencies to cooperate on making this a back up to the GPS system. The government recognized the inherent weaknesses of the GPS system and actually took some action to have back up. For those not familiar with the technicalities of both systems, the GPS signal is a very weak signal whereas the Loran signal is much stronger and thus much harder to jam or worse, to spoof. Additionally, the GPS satellites are much more vulnerable than the Loran transmitters.


Hopefully they will fully implement e-Loran within the next few years.

[Dehler 25]

I am a firm believer in maintaining back up options. I don't have the expertise to reach a conclusion about the vulnerabilities of the satellite system navigation is too fundamentally important to trust a singular system. I worked at a Loran transmitting station and question the true motivation to eradicate a system for the potential real estate.

[rlevin73]

If we lose GPS we would not have a time reference and Russia has been blocking GPS in the Black Sea

[Trimaran Ken]

Buy a good watch and use GPS to set it in case GPS goes down. Then you can stop using my tax money for something that is useless to me and almost everyone else in the US.

[fieldmedik]

one more from me

[Adelie]

Originally Posted by Trimaran Ken

Buy a good watch and use GPS to set it in case GPS goes down. Then you can stop using my tax money for something that is useless to me and almost everyone else in the US.

The same could be said about the navigation aids in Buzzards Bay, MA. Get rid of them “Then you can stop using my tax money for something that is useless to me and almost everyone else in the US.”

[Pete7]

Originally Posted by Adelie

The USNavy has started teaching celestial nav at the academy again because they realized the vulnerability of relying solely on GPS when out of sight of land for extended periods. The specific vulnerability they are most worried about is computer intrusion. CelNav is not being taught at the Academy for historical perspective or for any non-functional purpose it is being taught as the backup for GPS.

The RN is keeping a watch on this and continues to teach Cel Nav for the same reason, just too easy to jam or just alter signals.

There is a idea being floated to update sextants so they can recognise celestial bodies using a camera and then compute your position.

[Adelie]

You don’t need a sextant for that, just the camera itself is needed. The problem I see is in the post processing, specifically determining the horizon.
There has been a long discussion of CelNav using a camera on NavList.

[SSgtPitt]

Originally Posted by rlevin73

If we lose GPS we would not have a time reference and Russia has been blocking GPS in the Black Sea

How do you block GPS?
A $5 casio watch from Wal-mart keeps amazing time. So does my $10 battery operated clock. It’s about 20 years and I just changed the batteries for the 2nd time......Wal-Mart again.

[Dehler 25]

I am guessing you are willing to trust your life to something that can be set wrong. Inherent errors and inaccuracies were acceptable in 1732, today we have a higher standard. Interesting that you feel a minute savings is worth it, lets face it one less golf outing by a government official would fund the system for a decade.

[Adelie]

Originally Posted by SSgtPitt

How do you block GPS?

A $5 casio watch from Wal-mart keeps amazing time. So does my $10 battery operated clock. It’s about 20 years and I just changed the batteries for the 2nd time......Wal-Mart again.

Have you checked the error rate of either of those timepieces? If not then you really don’t know what time it is without reference to an outside source.

For use in celestial navigation every 1sec error in time will result in a 1/4nm error in longitude.

[ArmyDaveNY]

Originally Posted by SSgtPitt

How do you block GPS?

The GPS signal in not terribly strong, and a number of countries have jamming capabilities. Worse still, some have demonstrated an ability to spoof the signal and provide a false location. Iran claims to have captured a US Drone by doing just this. North Korea has been jamming GPS signals from time to time around Seoul. The British MOD a few years ago put out a notice that due to war games GPS may not be available in one area of the country or worse, may provide false signals.


On top of this, Communist China has a proven anti-satellite capability and it is most likely that Russia, the US, and others have or are working on such systems. The GPS satellites are not hardened against physical attach and most are not hardened against EW (electronic warfare).

[Adelie]

You don’t need to be a national actor to jam GPS. You can buy jammers that plug into your cigarette lighter. People buy these to jam the GPS trackers that employers put in their company vehicles. Periodically causes problems at airports.

[hellosailor]

I forget the name of the system, but IIRC there was a fully automaic astral navigation system deployed on the early U2 and some other USAF aircraft. In fact, it is said to be the inspiration for the way R2D2 "protruded" out of the top of a star wars fighter.

Technically, the system was fully capable of acquiring STARS IN DAYLIGHT and computing an exact [sic] position almost all the time. It was highly classified and very little was ever published about it, beyond the fact that it would let the USAF position critical aircraft without electronics (didn't exist to any great extent) or pilots using bubble sextants.

Someone somewhere still has the documentation and the ability to build more of them if they want backups without electronics.

GPS is very easy to jam, there have been multiple incidents of this intentionally and accidentally. IIRC something like 200 incidents of jamming AND SPOOFING in the US alone last year. While the authorities usually quietly swat this, the military does have antiradiation missiles for combat use against GPS jamming. You turn on the jammer, they fire one antiradiation missile (the same kind that target SAM base fire control radars so effectively) and there's a smoking crater where the jammer briefly was. So, in a combat situation? They have limited worries about GPS jamming. More real worries about attacks on the GPS satellites, which would be easy for any nation that can launch rockets.