How far you can sail in 24 hours? If you want to go on a sailing cruise, you need this sailing skill so that you can carry enough food, water, fuel, and sailing gear for your sailing crew. Use these simple sailing tips.
What type of sailboat do you sail?
Sailing speed depends on factors like weight (displacement), type of hull configuration (single or multi-hull), sailing ability of the boat in flat or choppy water, and how well the boat treats her crew (pitching like a bronco, or slicing through the water like a hot knife through butter?). Use this guide to estimate you expected speed over a day to help provision your small sailboat for cruising.
Displacement Cruising Sailboat Speed
Single hull, heavy cruising sailboats “displace” a certain amount of water. Imagine that you picked up a sailboat out of the water and the “water hole” the boat was in did not fill back in with water. The amount of water contained in that hole would about equal the advertised displacement of the sailboat.
For example, If a cruising sailboat has an advertised displacement of 28,000 pounds, then when in the water, she displaces that same amount of water. When sailing, she must push this amount of water out of the way. That creates a lot of friction and restricts the maximum speed that can be achieved.
To figure the maximum theoretical speed of a displacement sailboat, use this formula: 1.34 times the square root of the waterline. Multiply the result by 24 hours. This gives you the theoretical distance a displacement sailboat can cover each day.
First, locate the specifications for your sailboat or any other sailboat you are interested in. Look in the specification sheet, online, or in an advertisement. Here’s an example:
Oubound 44 Cruising Sailboat:
LOA 44’9″; DWL 40’3″, Beam 13’6″;
Draft 6’6″/5’6″; Displacement 28,000 lbs.;
Ballast 10,000 lbs.; Sail Area 1,083 sq, ft.
From the advertisement, you see that this Outbound sailboat has a displacement of 28,000 pounds. Determine her approximate maximum sailing speed with the formula for displacement sailboats. Follow these steps:
Find the square root of the Design Water Line (DWL) 40’03” = 40.25′. Square root of 40.25′ = 6.34 x 1.34 = 8.5 knots. Multiply 8.5 X 24 hours = 204 miles per day.
Remember this will always be just theory. Plan for those days when the winds are super light and your speed will be slower than the theoretical displacement speed. On the other hand, you will have days when you run downwind where you will exceed hull speed. The wise skipper will be ultra-conservative in his or her estimates. Some skippers of larger cruising boats would use a conservative estimate–like 150 miles per day–for sailing safety. That way, they can provision the boat with enough food, water, fuel, and sailing supplies for their crew. This covers unexpected events such as extra light or heavy sailing weather or crew emergencies.
Catamaran and Trimaran Sailboat Speed
Multi-hull (more than one hull) sailboats–called catamarans if they have two hulls, or trimarans if they have three hulls–have most of their hulls above the water. These boats are not slowed down as much by friction like their heavier displacement cruising cousins.
Big catamarans and trimarans can often exceed hull speed. Their speed over a sailing day depends on the sailing winds and seas. The sailing skipper may decide to slow the boat down while at sea (reefing or reducing sail) to avoid crew fatigue and boost crew comfort.
As recommended above, be conservative in your estimates–even in super fast cruising sailboats. Just because a boat can go fast all day long does not mean that her crew can. It’s a lot of wear and tear on a short-handed sailing crew to sail fast hour after hour. Some sailors of fast cruising boats like to plan for a maximum of 150 nautical miles per day for provisioning and arrival time estimates.
Other Sailing Speed Averages
Dinghy sailboats and small catamarans (i.e. Hobie Cat) skim across the water and have just a small amount of their hull beneath the water. This avoids most of the friction that heavy displacement cruising boats face. But, unlike cruising sailboats, dinghies have no room for lot of provisions–food, fuel, sailing gear, emergency sailing equipment–that you will need for sailing day after day when cruising.
So, unless you are that rare sailor who likes the smallest of accommodations, you will want to reserve sailing dinghies for day sailing trips. Day sailors go out for the day and return in the late afternoon or early evening. Plan you sailing so that you have plenty of time to make it back before darkness (unless you like sailing after dark–nothing quite like it!).
One plan would be to sail upwind or up current, beating or close reaching through most of the day. When it’s time to head back, you can then fall off to a comfortable broad reach or run. back to your marina or boat ramp. That way, you avoid a lot of hard tacking against the wind to make it back home.
Learn to sail with confidence when you know how to estimate how far you can sail in a day. Use these simple sailing tips to help plan and provision your next sailboat cruise–wherever in the world you choose to go sailing!