If you’ve always loved the idea of getting your own boat, the complicated jargon used by boatmakers can be frustrating.
You might reasonably wonder why one wouldn't use simpler terms for something as important as the boat's speed. What even is a knot?
25 knots on a boat equals 25 nautical miles per hour on the water. Such a boat travels at 28.8 miles per hour in a low resistance environment. The difference between road miles and nautical/maritime miles makes the use of 'knots' important when describing a boat's speed.
This post will cover everything you need to know about maritime vessel speed to make sure you not only understand what a knot means but also get the boat with the right knot coverage for your needs.
By the end, you’ll know more about the ideal knots on different types of boats and how you can measure the speed of a boat. But before we can have an insightful look at that, we need to establish what a knot is.
What Is a Knot, and How Are Knots Measured?
In the context of boats, the word 'knot' refers to a nautical mile. One knot is the number of maritime miles that the boat can cover in one hour. It doesn't translate to our understanding of land miles per hour, as there is a difference of about 15.1% between a knot and standard miles per hour. This is because the miles are measured differently in water and on land.
The knots on a boat can be measured in semi-controlled conditions testing where the knots are marked, and the boat speed is tested with a standard stopwatch. The knots are often decided by the kind of propeller the boat has and what its design predicts regarding its maritime speed. The quality control department checks whether the knot-predication is 'close enough to the practical speed of the boat. The speed is usually within a single knot margin of error.
One knot equals 1 mile on the waves and 1.151 miles on land. A propeller capable of moving a vehicle of weight X at 1.151 road miles an hour moves it at 1 mile per hour in maritime miles because of the difference in measurement. This difference makes the use of 'nautical mile' essential. A knot is a handy contraction of the term. That said, the example of a 1 knot per hour boat is a reductionist one, and most boats have far higher speed.
How Many Knots Is the Average Boat?
The average boat has 20 knots, with 12 knots being the lowest speed tier and 30 knots being the maximum speed ceiling for most boats. When getting a boat, one must opt for a vessel that has the broadest knot coverage capacity, even if speed isn't the buyer's primary preference.
You should opt for a boat with above-average maximum speed even if you like to sail at lower speed because this makes the boat easier to sell or trade. The boat's knot coverage can drive up its price, so ultimately, you have to make a choice based on whether you want a vessel that fits comfortably in your budget but leaves you illiquid or one that might stretch your expenses but will give you room to upgrade when needed.
The table below covers some knot-specific purchasing recommendations.
This is an ideal upper limit for knots on a central console boat. You can get her to be sold later or maintained as an investment.
How Many Knots Is a Fast Boat?
A fast boat is 60 knots, which means she travels at 69 miles per hour. The minimum speed of such a boat can be higher than small turnaround boats and fishing trawlers, which might make sailing in certain waters problematic.
However, getting such a boat means you have higher chances of reselling her whenever you like. She is ideal for non-congested waters and should be captained by someone with experience. A boat that has a 25-knot coverage is far better for the average hobbyist sailor.
Three Ways to Find Out Knots on a Boat
If you're interested in independently calculating the knots on a boat, there are three ways to find out a potential acquisition's nautical speed.
In the Product Prospectus
Most boats are custom-made to fit a model and make with predictable specs. These include the knot coverage, which is often listed on the product prospectus of a boatmaker. If making a secondary market purchase, you can ask the previous owner about its knots.
From Maritime Forums
You need to verify information about the boat regardless of whether you learn about the specs from a prospectus or a previous owner. Maritime forums like The Hull Truth and Band of Boaters can be used to get this information.
Calculate the Knot Coverage Yourself
Finally, for the uber skeptical, it is possible to triple-check a boat's knot coverage by doing a simple speed test with a standard stopwatch and using an mph to knot formula.
How to Convert Knots to Miles per Hour?
Whether you plan to do your own boat speed tests or simply want to be able to figure out a boat's speed in standard miles per hour, you can use the following method.
To convert knots to miles per hour, you need to multiply the number of knots by 1.151. The answer is the exact standard mile coverage of a boat. A 1-knot margin of error must be considered, so the speed might be 1.151 miles higher or lower than the result.
25 knots on a boat equal to 28.8 miles per hour in a statute equivalent. Such a boat is considered an average-speed vessel and can be used for low-impact maritime leisure. Her maximum speed of 25 knots predicts a low-end speed of 10 knots which is ideal for casual sailing.
About THE AUTHOR
I have a deep love of houseboating and the life-changing experiences houseboating has brought into my life. I’ve been going to Lake Powell on our family’s houseboat for over 30 years and have made many great memories, first as a child and now as a parent. My family has a passion for helping others have similar fun, safe experiences on their houseboat.Read More About Brian Samson