These are rough numbers, but it will give you a general sense of the different distances;
Downwind run: 100 NM
Long passages: 80 NM
Short passage: 60 NM
Engine use: 130 NM
Large yachts (over 60') in good conditions: 140 NM
1 NM is roughly 1.15 miles or 1.85 km.
Passages of multiple days allow you to sail non-stop, which increases the average distance per day. Shorter passages tend to result in lower averages. If the engine is used, sailors could increase their sailing distance by 20-40%. Larger yachts are able to cover up to 50% more distance per day, thanks to their length.
Of course it depends on many factors.
Your average sailing distance depends on your speed.
The average small sailboat (under 32') cruises at roughly 5 knots. A knot is the number of nautical miles per hour, so it's difficult to calculate the distance. 5 knots = 5 nautical miles per hour.
if you sail for 24 hours, that means you cover roughly 120 NM
if you use the tides and sail for 8 hours, you cover roughly 40 NM
The average mid-sized sailboat (32' - 48') cruises at roughly 6 knots.
if you sail for 24 hours, you cover on average 144 NM
if you sail for 8 hours, you cover roughly 50 NM
The average large yachts (over 50') cruises at about 7.5 knots.
if you sail for 24 hours, you cover on average 180 NM
if you sail for 8 hours, you cover roughly 60 NM
These are pretty optimistic estimates for optimal conditions, so let's take a look at all the things that can affect speed...
Hull length of the boat - The length of your boat is directly related to her cruising speed. A good rule of thumb is: the longer the boat, the faster she goes. On average, the following hull lengths cruise at roughly the following speeds:
24' - 5 knots
32' - 5.5 knots
40' - 6.5 knots
48' - 7 knots
54' - 7.5 knots
Hull type - Multihulls are considerably faster than monohulls because they displace a lot less water. With high speeds, they lift out of the water and start planing. They're also more buoyant than monohulls. This allows for much higher speeds.
Wind conditions - An upwind tack will be much slower than a downwind run. Picking the right course is very important for a good average sailing distance.
Tidal conditions - You can get a tidal advantage by sailing with the tide under you. The tide can carry you and increase your speed.
Engine use - If you use the engine every time you find yourself in light air, it's a lot easier to get a 5+ knot speed average. Using the engine increases the average sailing distance a lot.
Sail surface - If you have a large sail surface, for example by using your spinnaker a lot, you gain some speed, which increases the sailing distance.
Gear condition - The condition of your gear does affect the sailing speed. In fact, old, worn sails can reduce your cruising speed with 1 knot on average, maybe more. So if you're planning a long distance passage, be sure your sails are in good order. Same goes for the hull. If it's clean and smooth, it will create less friction, allowing it to go faster.
Sailing times - Sailboats can travel 24/7 on open seas, so they can cover a lot more miles than most people think.
How To Calculate the Average Sailing Distance
There are a couple of good ways to estimate the average sailing distance for your trip.
An old sailor's trick is to take the square root of the waterline (LWL) in feet. This actually gives you a surprising solid estimate for your boat.
If you want to calculate the maximum hull speed, the formula adds 34% to the square root of the LWL. That gives you an estimated maximum hull speed.
Another way is to keep a captain's log of your travel and calculate a real-world average for your boat and sailing skills. Simply divide your distance by sailing time. This gives you the average speed (in knots) or distance (in NM).
I also recommend asking sailors with experience on that particular passage what their average sailing distance was. Each passage is different and has specific conditions that you only get to know by actually going there.
In planning your trips, you should always be very conservative.
There will be days when there's no wind whatsoever, or days when you have to deal with wind shifts. Or something breaks.
And you never sail in a straight line, so be sure to add another 30% simply to account for drifting off course, making a navigational error, and so on.
Happy sailing!
Ross
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Passages of multiple days allow you to sail non-stop, which increases the average distance per day. Shorter passages tend to result in lower averages. If the engine is used, sailors could increase their sailing distance by 20-40%. Larger yachts are able to cover up to 50% more distance per day, thanks to their length.
