GPS Warning - Ches Bay Sailors

[Warren Milberg]

The USCG Nav Center has posted this notice, which centers around the Pax River Naval Station and Solomons Island:GPS NAVIGATIONAL SIGNAL UNRELIABLETHE GPS NAVIGATION SIGNAL MAY BE UNRELIABLE FROM 01 APR 08 - 31 OCT 08 DUE TO INTERFERENCE TESTING ON GPS FREQUENCIESUSED IN SHIPBOARD NAVIGATION AND HANDHELD SYSTEMS. SYSTEMS THAT RELY ON GPS, SUCH AS E-911, AIS AND DSC, MAY BE AFFECTEDWITHIN A 35 NM RADIUS OF POSITION 38-15-41N ,076-26-01W DURING THIS PERIOD. GPS USERS ARE ENCOURAGED TO REPORT ANY GPSSERVICE OUTAGES THAT THEY MAY EXPERIENCE DURING THIS TESTING VIA THE NAVIGATION INFORMATION SERVICE (NIS) BY CALLING(703)313-5900 OR BY USING THE NAVCEN'S WEB SITE'S 'GPS REPORT A PROBLEM WORKSHEET' AT WWW.NAVCEN.USCG.GOV"The United States Coast Guard Navigational Information Service (NIS), operated by the USCG Navigation Center, is staffed 24/7.

 

[Jim Seamans]

Damn thats almost the entire middle bay and Potomac

I show it going north to Herring Bay, West to Colonial Beach on the Potomac and south to Tangier Island. That could affect a lot of people.

 

[John24107]

Try this

Beginners Celestial Navigation Kit

 

[Ross]

What a wonderful opportunity to practice our coastal piloting

skills. I am afraid that Celestial is not very useful in The Bay.

 

[MafaldaII]

I can't find that notice

It gets me really worried, thats my sailing area. Here is what I found for inteference tests for 2008

 

[s sauer]

Visibility?

Unless it's foggy, raining or we are far south in the middle of the Bay, can't we usually see both shores? A compass, a chart and the depth sounder, plus hundreds of navigation aids... what's to worry about?I do use my handheld to find unlighted day marks marking Swan Point bar at night... I used to use a 1,000 candlepower hand held search light many years ago... still have it aboard as a back-up.

 

[Jim Seamans]

I think that losing the signal

at the wrong time would be a little uncomfortable. I would hate to out somewhere in very reduced visibility trying to navigate to a entrance fix.

 

[RichH]

Coastal piloting in the Chesapeake Bay ....

The Chesapeake is approx. 200 miles long by 6-7 miles wide (at its 'fattest').Simple Chesapeake Navigation: when lost go either W or E until close to or hitting land, then turn to port or starboard and follow until you find 'something'. BIG buoys are where the ships go, BIG ships dont usually hit things so stay close to the BIG thingys in the middle. If your depth sounder beeps turn to the 'middle'. The only way to get OUT of the bay is to go under the BIG bridge at Norfolk ... or the little canal at the top of the bay, that's it. Coastal piloting will never work (again), as its a totally lost art, forever gone. I keep my boat on the Upper Chesapeake, and almost EVERY late Sunday night there will be at least ONE lost and totally bewildered powerboater drawn by the bright light of my marina. The usual 'discussion' goes like this: "Where am I? "I want to go to XXXX (holds up Exxon Road Map showing where he/she wants to go). Without breaking a smile I simply tell them "Oh, thats over on the Chesapeake Bay. How did you get over here?" .... and I turn and walk away. (the Delaware Bay is fairly close so the inference is quite obvious) ..... then, when they regain composure, stop fighting / abusing one another or start to breathe again, I tell them. .... and they always have absolutely NO idea. This occurs just about EVERY damn Sunday night on Worton Creek.Usually - no charts (sometimes maybe a placemat from a bayside restaurant), no idea, out of beer, porta-potty is full, grumpy wife/SO, no gas, .... but they DO have a GPS or an Exxon Road Map !!!!! O Come on Ross, you want these Eloi folks to Coastal Navigate? - hardly; at least not until "Watermans Restaurant" puts a north south 'arrow' on their dining room placements. Sometimes I think they put that large bridge/tunnel at Norfolk and the little canal at the 'top' ..... just to keep the idiots IN the Chesapeake. .... ;-) ... with MD boat registration they probably work for the 'gummint' .... and they vote. I just cant wait until the local GPS get scrambled by the PAX Naval Station .... going to be FUN for Towboat/US !!!!!!

 

[Jim Seamans]

love it Rich

A few years ago we were headed home during some nasty rain storms. Several power boats passed up headed river. Then here comes another boat who passes then stops and turns and comes up behind us. "Is it ok if we follow you we can't see to well."They didn't even use their radio, the wife was hollering out from the bimini.They didn't follow us after we told them we were turning into the island in about a mile. We laughed all the way to the dock.

 

[Ross]

There was a bass fishing tournament up here a few years ago

Nancy and I were returning from somewhere when we were hailed by a young couple in a bass boat. You know the type real pretty paint job and real pretty girl. Did I know where Elkneck state park was? I told him I knew and pointed. There are five rivers that converg at Turkey point Elk Neck. This day was foggy with visibility only about three miles. The man didn't have charts, compass, VHF, or GPS. So I pulled my charts and showed him where we were and where he needed to go. He Thanked me kindly at took off at about forty mile per hour into the fog in the direction of Turkey Point. I didn't read about a missing fisherman and his girlfriend so I suppose they made it..Rich. You know the ADC book maps aren't too bad a substitute for a bay chart. ;D

 

[RichH]

I find the ADC chart book ...

as accurate as govt. charts, better colors, are based on WGS84 datums, foldable, waterproof, pencil courses are easily erasable, reasonably priced, covers the WHOLE bay and most of the Atlantic Coast of VA/MD ... did I say 'love' that chart book. Too damn bad that batteries are not included. D'ya think the ADC will be OK to use near PAX this summer?. The official MD guide chart book is based on old NAD1927 datum, isnt waterproof, only covers MD, yet still better than a bundle of 'gummint' charts. BTW many of the 'tournament' participants, sneak in weeks beforehand & build underwater 'brush piles' accurately GPS plotted ... have their 'time' at each pile 'optimized' (unless the pile is 'active') ..... and usually catch a BIG ONE just about 'every early Saturday morning' under the catwalk to my slip. Every week a 'NEW' BIG ONE replaces the one that was caught .... sometimes there will be 3 or 4 tournamenteers fighting to get under 'my' dock at the 'bulkhead' catwalk. These tournament folks travel over several states each weekend .... the payout must be that good.

 

[Ross]

Rich, I was refering to the county road map books

They don't tell you how much water you have but they get the shoreline in the right places. I use the ADC Chart books. I haven't ever found any errors in them.

 

[Buck2796]

Well,

Let's see, based on all this information;From now thru Oct, within 35mi of Pax River, occasionally, the sailboaters will just go back to their paper charts, rulers, and pointy things; and yell "Martha, what the H--- is the # on that green thingy over there?". The power boaters will never know anything is different, (nor would they care).The real problem will come when people driving their cars get lost because their computer nav. maps send them off in the wrong direction. Irate drivers will call the Solomans Is. newspaper. Horrible newpaper stories will appear about the crisis in public safety caused by Gov'ment testing at Pax River. Senator Warner will be contacted. He will contact the Sec. of the Navy and order the GPS testing to stop, (or only take place between 02:00 and 04:00). The sailboaters will go back to using their GPS chartplotters w/o interruptions. The powerboaters will continue to never know (nor care) anything happened.Problem solvedOh Rich,Down here at the South end, the Bay is about 20mi wide; and we don't have any BIG bridges. Smart engineers (like yourself) built funny tubes under the BIG channels so we (and the BIG ships) can get in and out, (and try to stay clear of the powerboaters). You guys way up there in the North should come down sometime and enjoy the Big end of the Bay... if you can get past the treacherous navigation Blackhole thought to possibly exist on or near Pax River.

 

[Warren Milberg]

While I agree with most posters

here that navigation on the Chesapeake is generally an easy eye-ball affair, if you've ever been caught in a fog or you sail at night, the use of a an accurate GPS is pretty helpful. The problem this notice brings to mind is the potential for not knowing when your GPS is being "dithered" with or has become "inaccurate" for reasons you don't know about. Recognizing that has happened, and taking corrective action, could be critical. What I take from this warning from USCG is the old and true message about never depending on a single form of navigation.

 

[GuyT]

LORAN to the rescue

Can't throw mine away cause it still works great and it is a great backup.Does anyone else still use theirs?

 

[Buck2796]

Warren,

In all seriousness,(if we have to be serious), I, of course, agree w/ you.Does anyone (like "Boat US", ?) have the clout to ask the USCG to make "Pan-Pan", VHF announcements when the GPS signal is being degraded due to "interference testing"? They routinely broadcast VHF warnings of other hazzards to navigation. Shouldn't this also be considered a hazzard to navigation for commerical as well as pleasure craft?

 

[Ross]

I suspect that the navy wants those reports

of GPS interference to enhance their own data collection. If they announced the operations, the reports of GPS aberations would be biased.

 

[RichH]

You can bet your bippy ....

that the Russians or the Chinese would love to get such broadcast advisories. Would save time and travel distance for those who most probably would be monitoring the magnitude of the 'dithering'.I also note that the 35 mile radius affected area is conveniently omitting the Russian Embassy Summer Residence on the Chester River / Corsica River. Think about the direction control of 'smart weapons' depending on "GPS", Now all we need to figure out is mirrors to reflect back the laser spotting. ;-o

 

[elle]

GPS accuracy

This testing situation will not be constant; rather, it will be intermittent. Check your GPS for a function that allows you to check its accuracy. Get a feel for the margin or error (mine is anywhere from @10-30 or so feet.)If you check it on occasion while out and notice that the error is not within the usual range, that may be an indicator that they're playing with it again.Then again, we could always look out the window.....elle

 

[Benny17441]

To purposely degrade the GPS signal in

heavily transited US waterways is irresposible at best. I think testing can be conducted in other areas under a controlled environment. I'm sure exceptions to the order to stop the differential degradation of the GPS signal does not include using pleasure boaters as guinea pigs.