Knots vs. MPH

I think not. Airplanes, yes. Boats, usually, at least in salt water. Probably not as often on inland lakes and rivers. Car navigation, no. Backpacking, camping, hiking, no.

A lot of this is done in kilometers in other countries.

Back when we boaters mostly used paper charts, it was convenient to have the latitude scales handy for caliper measurements. It's still nice to know how to do that stuff.

However, chartplotters and GPS units will work in any scale you choose and the latitude idea is mostly worthless any more. It's useful to know the conversions because when you're planning a trip or reading an article, some of the information will be in one set of units and some other information will be in others. Crazy mixed up world. Deal with it.

One man's opinion.

Jeff Lastofka
 
The observation re the Corps of Engineers is correct. The mile markers were already in place when the Army changed to metric to meet NATO standards. It is also a fact that the Corps of Engineers is not interested in maintaining the ICW in any respect, including the mile markers, which are not replaced when they deteriorate. As a system for location, the milemarker/statute mile stuff is destined to disappear.

I guess that if you never get out of the Ditch, it doen't matter. Otherwise, the 1' of Lat=1 NM is a fundamental concept of all navigational skills. Should someone report an emergency position to the CG in something other than LAT/LON and NM, delays will result while the Watchstander tries to find somebody who can translate.

I am not a big fan of chartplotters because (1) they can fail; and (2) other than deleting and replacing the application with a complete update, there is no way to incorporate changes from the NtoM and LNM. If you are going to maintain paper charts, as I feel I must, why bother with a big tv set that mainly just blocks my vision.

Finally, I would recommend Bill Brogden's book, Boat Navigation for the Rest of Us, in particular the many sections that focus on Seaman's Eye and formulae for making approximate calculations with minimal distraction.
 
The observation re the Corps of Engineers is correct. The mile markers were already in place when the Army changed to metric to meet NATO standards. It is also a fact that the Corps of Engineers is not interested in maintaining the ICW in any respect, including the mile markers, which are not replaced when they deteriorate. As a system for location, the milemarker/statute mile stuff is destined to disappear.

I guess that if you never get out of the Ditch, it doen't matter. Otherwise, the 1' of Lat=1 NM is a fundamental concept of all navigational skills. Should someone report an emergency position to the CG in something other than LAT/LON and NM, delays will result while the Watchstander tries to find somebody who can translate.

I am not a big fan of chartplotters because (1) they can fail; and (2) other than deleting and replacing the application with a complete update, there is no way to incorporate changes from the NtoM and LNM. If you are going to maintain paper charts, as I feel I must, why bother with a big tv set that mainly just blocks my vision.

Finally, I would recommend Bill Brogden's book, Boat Navigation for the Rest of Us, in particular the many sections that focus on Seaman's Eye and formulae for making approximate calculations with minimal distraction.
 
In our area, the aids to navigation (marked in statuate miles) are maintained by the ATN Coast Guard team. The positions for distress in inland waters are given in Statuate mile marker--and at sea by lat and long.

The Corp is "responsiable" for dredging--and the budget is very limited. That is why "maintance" is limited--especially in the East Coast ICW where there is frequent shoaling. There are also a number of environmental and political issues involved in dredging. I am not appologizing for the Corp, but explaining why. There is a lobby group, and joining that helps: Atlantic Intracoastal Waterway Association.

The Corp of engineers involvement in maintance of the ICW (and probably most waterways) started in 1923, after a yacht which President Harding was aboard ran agound twice (Harding went ashore and played golf), and Harding directed the Corp to conduct "economic assesments" of the canals, and this morfed into the ICW. I suspect that certainly this event was key in keeping the measurement in statute miles, but also suspect that canals, such as the Erie, were already measured in miles long before the Corp was involved. I suspect that the Mississippi river (and others) which were the backbone of the developement of mid America were also measured in statute miles early in the history. I have an 1867 US map (the origional one my great grandfather carried across the US after being appointed the first Federal Land attorney in S. Calif.) It shows distances on the Rivers in statute miles.

It is interesting that up in your neck of the woods, that ATN are not maintained. They are carefully maintained in the Gulf Coast ICW. We have a lot of commerace on the GCICW. I suspect that the Atlantic ICW is mostly pleasure boats, and as such we "don't count".
 
Sorry for the double post. I did not say nor mean to imply that ATON's in Sector NC are not maintained. Our three CG ANT's do a superb job. Not maintained are the CoE St. Mi. markers, many of which are bare pilings now, if that. Those locations are identified on the "small craft" charts, and the Coast Pilot (AICWW chapter) locates all manner of infrastructure by tenths of St Mi. My point is that without the mile markers and without an odometer, all this is less useful than if lat/lon were used, as is the case in all other Coast Pilot chapters, the Light List, etc.
IMNSHO, the CoE has a huge budget, but they prefer to build gradiose projects no one wants, so that Congress will provide the additional $ for what folks really need. This has worked until now, when massive deficits leave no $ for anything. Commercial traffic on the AICWW diminishes each year due to a lack of dredging, which the CoE then cites to justify even less dredging=self-fulfilling prophecy.
 
Billwoodhouse, You make some excellent points. It is interesting that ATN Coast Guard appears to maintain all of the ATN in the Gulf Coast ICW, at least as depicted in the NOAA charts. (Which we all know are often out of date, and unreliable as far as shoaling). Some of the ATN are privately placed and maintained; mentioned in the light list, but not on charts. I put in 4 ATN on Bayou Chico--and the process took a year to get CG blessing and get them on the light list.

I'll have to disagree slightly about the chart plotter (and I am an old fashioned guy who does use his paper charts or chart books). You can put in annotations in many of them, by placing a mark. I always plan my route using paper charts, and Marie checks off the mile markers. I have yet to have a chart plotter fail--and I currently own 9 (including hand helds, car/RV and back ups).

I wonder how many keep their charts updated with LNM? I used to at one point on the West coast--but there are so many changes on the ICW, I don't any more. The chart chip manufactuers are getting a bit better about updates (at least some are--not sure with companies being sold recently). There are chip exchange programs, which are every 6 months to a year--and that is far more frequently than NOAA charts are updated--unless you go to Print on Demand. Many years ago, when you purchased a NOAA or DMA chart from a chart company, it was hand updated thru the most recent LNM as you waited. Sometimes a chartlet was pasted over the old chart.

When I was using sailboats, I felt no real need for a chartplotter (but the last of that was over 10 years ago--and there were not many in-expensive chart plotters). Today, at the speeds our CD boats travel, the chart plotter is a Godsend. It allows one to "see" the route ahead, especially in areas where the ICW and local channels merge and there is easy convusion by just looking at charts. The alternative is to slow down, and get the binoculars out to check the bouy numbers.

As far as distress: the point is well taken that lat long is a universal way to give a location. However, I suspect that 90% of the recreational boaters and probably almost as many commercial operators in our area don't know what the lat lon is at their current position, but do know where mile mark 275 is. We had one commercial operator (49 passanger charter boat skipper) misplace reef material in the aircraft carrier channel because they were unable to distinguish Lat from Lon in measurements. If I wanted help on the Gulf Coast ICW, I would give a mile marker position, rather than Lat long (unless the CG requested it)--and lat lon is available right on my GPS and radio, because the chance of a recreational or commercial boater comming to my rescue is far better (again, this is just in this specific area--and does not hold true for many other areas). This re-inforces that one should do what is the accepted practice in their area, but be prepared to give information in a universal format also.

I don't know if you are aware of Salty Southeast Cruisers net:
http://www.cruisersnet.net/index.php
(warning Watermark publications advertises their books on this site). There are up to date cruising notes which are passed on a regular basis to the local cruising notes--and in many ways more helpful than LNT. There were 36 posts about North Carolina ICW and cruising areas on July 9th alone..On the other land LNT covering a large area(District 5) for the same date is 27 PDF pages, and I have difficulty scraping the pertent information out of this.

Regards,

Bob
 
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