I find it always informative, often inspiring, and sometimes very entertaining
And like a lot of us, I visit it almost daily, and contribute a post here and there when I think I can add value to the topic. But .. I have one Pet Peeve that I need to get off my chest, so please indulge my following rant.
NOT using KNOTS!
We are sailors, and sailors use the Nautical System for expressing “Speed and Distance” when on the water.
- We do not use the Imperial or Metric systems, or any other.
- We express: Boat Speed, Wind Speed, and Tidal Current Speed … in Knots.
- We express: Distance in … Nautical Miles.
So many people use MPH or KPH. This drives me nuts!
1) I would expect this from fisherman, but not from us sailors
I can say that because I am a recreational fisherman and my ocean-going fast-boat fishin’ buddies wouldn’t know how fast a knot was if it was stuck up their transom. When I asked how fast his new boat goes he said “80 KPH”. I said “how many knots”, he said “with an engine this big I don’t need to know that stuff”. He’s been on the water a lot longer than I have, and we catch lots of big Pacific Salmon, but I always wear my PFD done up a little tighter when onboard with that skipper.2) I can also see why boat manufacturers like MacGregor express their top speed as 24 MPH. I sounds faster than 21 knots, and their biggest buying demographic is new boaters who probably do not know how fast 21 knots is.
3) I can also see why people who do not know the Nautical System would use their Native System. It’s their natural reference. I am Canadian, and was raised in the 60’s on the Imperial System, then in the 70’s I had to convert to the Metric System. But when I started sailing, I learned the Nautical System.
Why Use Knots?
1) First and foremost: it’s just plain Good Seamanship.
As skippers, we are responsible for the safety or our vessel and crew (friends and family). This nautical system form of measuring speed and distance is universal. Regardless of what system you use on land, Sailors (boaters) have a common language on the water.
2) Second: All Nautical Charts are measured in Nautical Miles, for a reason. And that reason is because the world is round. If you want specific details of the why, see this website http://www.onlineconversion.com/faq_07.htm
3) Third: All Tide Charts express tidal current speed in Knots for a reason). I sail in the Pacific Northwest were tides can be up to 14 feet, and tidal current run to 7 knots in tide-gates. Knowing how many knots the current is verse how many knots my boat can go is extremely important to passage planning and safety.
4) Fourth: In order to do any proper passage planning you need to be comparing apples with apples. By that I mean nautical miles verses knots of boat speed. If your planned trip is 30 nautical miles, and you cruise at 10 knots, it will take you 3 hours. It’s simple, and easy math. Is that not easier than trying to figure out how far it will take you to go 30 nautical miles on the chart at a speed of 11.5 mph. (hint: 11.5 mph is 10 knots). If you do not know how to calculate Distance/Speed/Time, use the “60-D-STreet” rule. See this website: http://www.boatsafe.com/nauticalknowhow/eta.htm.
5) Fifth: Fuel consumption/distance calculations: Using Nautical Miles and Knot Speed is more accurate and safer. I know that on average we use 1 litre of fuel for every 1 nautical mile traveled (cruising at 4800rpm making 8-10 knots over ground). We have 2x34 litre tanks on board for a total of 68 liters of fuel, so our onboard range is about 70+ nautical miles. I need to switch fuel tanks at the 35 nautical mile mark. So in my passage planning, I will see where that is on the chart and ensure it is a safe place to switch tanks, if not I will make a note to change tanks earlier. * I also understand the benefit of calculating fuel consumption per hour based on rpm. Especially where tidal current has a strong effect on consumption and speed.
6) Chart Water Depths are different. Some are Meters, some Fathoms, some Feet.
Final thoughts:
If you are NOT using the Nautical System because:
- you don’t know how. Please learn. Take a navigation course. It will pay off for you and your family.
If you are NOT using the Nautical System because:
- you don’t want to. Then stop it! We are sailors, use the on the water nautical language so we all can communicate better.
Wow, I feel better now I got that off my chest. Thanks for letting me rant
Darry
