Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 23-11-2010, 16:32   #1
Registered User
 
ozskipper's Avatar

Join Date: Aug 2010
Location: NSW Australia
Boat: Traditional 30
Posts: 1,981
Don't Rely on GPS ?

Do you think its probably not a good time to rely on GPS at the moment. If the Nth Korean problem escalates, we could see a few satelites being shut down/adjusted prior to any retaliations Similar to Iraq 1 and 2.

One would assume the USA would shut hers down to give the South Korean allies a chance to pop a few salvos off.

(I dont want to start a political thread. Trying mainly to get an idea what other people think. Particularly, people who have been affected previously and to what level.)

Cheers
Oz
__________________

__________________
ozskipper is offline   Reply With Quote
Old 23-11-2010, 16:44   #2
CF Adviser
 
Bash's Avatar

Cruisers Forum Supporter

Join Date: Dec 2008
Location: sausalito
Boat: 14 meter sloop
Posts: 7,260
I should think that if the North Koreans are using GPS, they'd be using the Russian system.
__________________

__________________
cruising is entirely about showing up--in boat shoes.
Bash is offline   Reply With Quote
Old 23-11-2010, 16:59   #3
Eternal Member
 
capt_douglas's Avatar

Join Date: May 2003
Location: Ft. Lauderdale, FL
Boat: Vancouver 36 cutter????
Posts: 620
Send a message via Skype™ to capt_douglas
Why would the US shut down GPS when they have very effective electronic jamming technology?

And so do the South Koreans. And the Israelis. And probably the Chinese. And a lot of other countries.
__________________
Capt. Douglas Abbott
USCG/MCA IV/M.I./C.I. 500-ton Oceans
capt_douglas is offline   Reply With Quote
Old 23-11-2010, 17:02   #4
Registered User
 
ozskipper's Avatar

Join Date: Aug 2010
Location: NSW Australia
Boat: Traditional 30
Posts: 1,981
Quote:
Originally Posted by capt_douglas View Post
Why would the US shut down GPS when they have very effective electronic jamming technology?

And so do the South Koreans. And the Israelis. And probably the Chinese. And a lot of other countries.
Perhaps I got the type of technology wrong or the method. But what my point is, is that GPS was made unreliable prior to previous escalations.
__________________
ozskipper is offline   Reply With Quote
Old 23-11-2010, 17:21   #5
CF Adviser
 
Bash's Avatar

Cruisers Forum Supporter

Join Date: Dec 2008
Location: sausalito
Boat: 14 meter sloop
Posts: 7,260
Quote:
Originally Posted by ozskipper View Post
Perhaps I got the type of technology wrong or the method. But what my point is, is that GPS was made unreliable prior to previous escalations.
That technology was called "selective availability." We all used to live with it. Instead of knowing where you were within ten meters, you had to do with a 100-meter fix. But most of us found that if you got us within 100 meters of a destination, we could take it from there.
__________________
cruising is entirely about showing up--in boat shoes.
Bash is offline   Reply With Quote
Old 23-11-2010, 17:29   #6
Registered User
 
rover88's Avatar

Join Date: Nov 2008
Location: Panhandle of Florida USA
Boat: Bristol 34
Posts: 328
Images: 4
How reliable is GPS?

There was a good article in the recent issue of "Good Old Boat" addressing the myriad of things that can affect GPS, including a US government shutdown, a 17 year old computer geek hacking the system and good old sunspots.

I recently proposed, under a thread "Is it time to buy a sextant?", the same sort of question and stirred a rather lively debate. Some folks are very trusting of technology, while others (like me) are mildly suspicious of anything requiring batteries, electricity or - more specifically - government permission.

God forbid I should loose my chartplotter, as I have become rather fond of the device and a little lax in keeping up my traditional navigation prowess.

Now that winter is here and sailing limited I suppose it would be smart to hone those outdated skills involving paper charts, compass and - yes - even my sextant.

So, to answer your question - rely solely on your GPS at your own peril.
__________________
rover88 is offline   Reply With Quote
Old 23-11-2010, 17:33   #7
Registered User
 
capn_billl's Avatar

Join Date: Aug 2010
Location: Houston,Tx
Boat: Maxum 37'
Posts: 1,587
Keep a backup. The satelites can be turned off or shut down. Or even destroyed, (by chinese antisatelite missile already successfully tested). Or your chartplotter can be knocked offline or fried by lightening. The sextant never fails.
__________________
capn_billl is offline   Reply With Quote
Old 23-11-2010, 17:45   #8
Registered User

Join Date: Feb 2008
Posts: 2,061
Quote:
Originally Posted by capn_billl View Post
...snip
The sextant never fails.
HUH??? It fails when under clouds and fog and every kind of inclement weather... probably mostly when you need it most.
__________________
SailFastTri is offline   Reply With Quote
Old 23-11-2010, 18:16   #9
Registered User
 
Alexei's Avatar

Join Date: May 2008
Location: NY (me), Charleston SC (Icefire)
Boat: 1974 Sabre 28 Mk I - Icefire
Posts: 140
I highly doubt we'll re-encrypt GPS any time soon. So much runs off GPS that we'd be shooting ourselves in the foot if we did.

That said, never rely on GPS alone. There are all kinds of things that interfere with reception and/or affect it's accuracy. A proper mariner utilizes all forms of navigation and is proficient with them.
__________________
Alexei
S/V Icefire - 1974 Sabre 28 Mk I (Hull # 89)
http://sailsandstars.blogspot.com
Alexei is offline   Reply With Quote
Old 24-11-2010, 06:13   #10
Registered User
 
svHyLyte's Avatar

Join Date: Mar 2006
Location: Tampa Bay area, USA
Boat: Beneteau First 42
Posts: 3,434
Images: 25
FYI at the commencement of Operation Desert Shield, the (1st) Bush Administration discontinued selective availability signal dithering, which improved, not degraded, the accuracy of civilian GPS devices, as so many military units were relying on civilian rather than military spec units. Not long afterward, selective availability was discontinued altogether after which Wide Area Augmentation was implemented, reportedly to increase the accuracy of GPS enabled "smart bombs" (whether that is so or not I have no idea, but WAAS is a reality).
__________________
"It is not so much for its beauty that the Sea makes a claim upon men's hearts, as for that subtle something, that quality of air, that emanation from the waves, that so wonderfully renews a weary spirit."
svHyLyte is offline   Reply With Quote
Old 24-11-2010, 06:27   #11
Registered User
 
Bill_E's Avatar

Join Date: Aug 2008
Location: New Mexico and Puerto Rico
Boat: Sunbeam, 37, Ziamar
Posts: 300
I've gotten to love my chartplotter and gps/laptop/charting program. Unfortunately it has allowed me to be very lax with things like dead reckoning and hourly charting. I still rely heavily on paper chartbooks. I've also found that whenever you get close to land, eyeball, compass, and binoculars are invaluable. Selective availability wouldn't really hurt because knowing where you are within 100 ft is probably good enough for 99+% of the time.

I doubt very seriously if the Govt will turn off the satellites but lightning or other electrical problems could seriously affect my gps service.

Here's an interesting link about Selective Availability in case anyone is interested Information about the End of GPS Selective Availability
__________________
Don't believe everything you think
Bill_E is offline   Reply With Quote
Old 24-11-2010, 07:13   #12
Eternal Member
 
capt_douglas's Avatar

Join Date: May 2003
Location: Ft. Lauderdale, FL
Boat: Vancouver 36 cutter????
Posts: 620
Send a message via Skype™ to capt_douglas
A prudent and prepared sailor never relies on one source of information for their position. DR, celestial, or range and bearings should be used in conjunction with common sense and eyesight to make sure the gizmo is telling you the truth based on the view from the cockpit.
__________________
Capt. Douglas Abbott
USCG/MCA IV/M.I./C.I. 500-ton Oceans
capt_douglas is offline   Reply With Quote
Old 24-11-2010, 07:41   #13
Registered User
 
mbianka's Avatar

Join Date: Mar 2008
Posts: 2,125
Images: 1
Quote:
Originally Posted by capt_douglas View Post
A prudent and prepared sailor never relies on one source of information for their position. DR, celestial, or range and bearings should be used in conjunction with common sense and eyesight to make sure the gizmo is telling you the truth based on the view from the cockpit.

Amen to that!
__________________
Capt. Mike
mbianka is offline   Reply With Quote
Old 24-11-2010, 08:20   #14
Senior Cruiser
 
bstreep's Avatar

Cruisers Forum Supporter

Join Date: Oct 2007
Location: San Antonio, TX/Port Aransas, TX
Boat: 1990 Macintosh 47, "Merlin"
Posts: 2,274
I"m a real estate appraiser. All of us now use GPS units in our jobs - it just makes sense. However, when we discuss it, we ALL lament how it has degraded our mapping skills AND our ability to recognize where we are (what part of town, what's nearby, etc.). I've made an effort to continue to use map books ("paper charts"), to keep my skills up.
__________________
Bill Streep
San Antonio/Port Aransas, TX
bstreep is offline   Reply With Quote
Old 24-11-2010, 08:46   #15
Senior Cruiser
 
osirissail's Avatar

Cruisers Forum Supporter

Join Date: Feb 2009
Location: A real life Zombie from FL
Boat: Gulfstar 53 - Osiris
Posts: 5,416
Images: 2
Quote:
Originally Posted by capt_douglas View Post
A prudent and prepared sailor never relies on one source of information for their position. DR, celestial, or range and bearings should be used in conjunction with common sense and eyesight to make sure the gizmo is telling you the truth based on the view from the cockpit.
For anybody sailing out of sight of land and not heeding the above - you are really inviting your early demise.

- - On forums like this and other "specialized" forums there is a tendency to think that we are the only users of a specific service - like GPS in this case. Fact is, the whole world and world economy is tied into GPS and shutting it down is politically impossible short off Global Nuclear War - and probably not even then as it is needed to guide the H-bombs/bombers.
- - Every aspect of local transportation from cars, trucking, trains, airlines and private aircraft are all completely enmeshed in GPS location. Add in International commerce from airlines to super tankers who all rely on GPS for tracking and position reporting.
- - Simply put GPS is here to stay and will not be "turned off" in any way, shape, or form short of humans wiping themselves off the planet or Mother Nature doing the job for us.
__________________

__________________
osirissail is offline   Reply With Quote
Reply

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
GPS Not Seen glenn.225 OpenCPN 42 16-06-2010 07:07
Furuno GPS - 'GPS Week Number Rollover' bitman Navigation 0 25-11-2009 04:53
GPS $65 Jmolan Navigation 2 09-11-2009 17:28
New GPS? Zach Marine Electronics 0 22-07-2007 20:29



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 23:20.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.