Displaying speed/distance in Knots/MPH and miles ?

[baz]

Subject: Displaying speed/distance in Knots/MPH and miles ?

I suspect people/boaters/sailers all have a different perspective on displaying data such as Knots, Nautical miles, Statute miles and MPH.

Personally I like (after many years) to favor the Statute miles and MPH data to view when underway, even though I've grown up sailing and motoring for many years and love the nautical terminologies.

When passengers (adults and kids) who don't have a nautical background ask me "How much further to go" or "What's the speed" or "How fast can the boat go" they much prefer and understand more fully if I reply with Statute miles and MPH. They look kind of puzzled if I respond with Knots or Nautical miles.

For these reasons I configure my Garmin devices and Engine displays to display miles, GPH, MPG and MPH data.

How do others deal with communicating the above data to their passengers, and what really is being 'missed' by not using the Nautical data such as Knots and Nautical miles etc ?

 

[bill46]

We use statute miles as we cruise the Intercoastal and St. Johns, both of which are marked in Statute.
Knots are OK for open ocean, and 60 nautical miles is a minute of latitude.

 

[mjq1987]

In terms of purely using electronic navigation I don't think you lose anything, but if you enjoy doing the mental gym outside of the electronic systems you can't use nautical thumb rules like the 3 Minute Rule or 1 deg at 1 nm = 35 yds x-track, etc.

 

[Red Raven]

I know it’s weird but I configure the engine display to show knots and the Garmin to show mph. Then both are available all times.

Curt

 

[Chimo]

I know it’s weird but I configure the engine display to show knots and the Garmin to show mph. Then both are available all times.

Curt

I do the same and I configure my plotter depths in feet even though Canadian charts are in meters. When I was trained in open ocean navigation it was obvious to use knots because, as already stated, 1’ of latitude is equal to one nautical mile and one could always scale distances from latitude at the side of a Mercator chart using dividers. Brings back memories of shooting the midday sun with a sextant and correcting compass readings. I must admit I still have my hand bearing compass left over from the days of boating on the Chesapeake Bay when it was easier to fix a position with sightings rather than using Loran.

Apologies for drifting off topic.............

 

[NorthernFocus]

Nowadays with electronic navigation and most people never seeing/touching a paper chart, much less plotting on one, it really doesn't matter. They each have advantages depending on one's perspective. When on the water most people convert everything into time anyway. As others have pointed out the traditional nautical system does relate to the degree system on the chart but nowadays that is no real advantage as many people, including the USCG, use the decimal system rather than minutes/seconds anyhow. There is the convenience of quickly calculating/estimating short range time of travel, i.e. knots x 100 = feet traveled per minute. More useful for sailors or hull speed cruisers.

And regardless of one's preference, it doesn't exactly take higher math skills to do the conversion from one to the other.

 

[Pilotnavigator]

Dont you mean one minute of latitude is one nautical mile?

 

[Navigator's Son]

How do others deal with communicating the above data to their passenger?

Easy. I boat alone :lol: