Efficient Sailing: passage routing

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There’s a problem: many cruisers think that sailing performance isn’t important. Hey, cruising is about slowing down, right?! But dismissing performance is poor seamanship. Part two in a series.

Efficient sailing is partly about sail trim and sail handling (that’s covered here), and partly about routing. With a few rules, routing from A to B can be faster (and safer).

dsc_3791Big picture routing—should we take the northern or southern route across the Indian Ocean?—is fun and easy. String together an efficient and safe path to the places that you want to visit. Take into account big considerations: seasonal weather patterns, time limitations, access to fuel/food/etc. The scientific formula for big picture routing is: fun – harm = intentions. What you actually do depends on a millions variables that happen as you step along the path.

Zoom in on details of sailing to the next place and you’re into A to B routing. Sometimes this is easy; a straight path without complicating factors. Often subtle variables can cost you time or diesel, and elevate risk.

Going from Seattle to Friday Harbor, you look at the weather and the tide for when you expect to be at Cattle Pass. This is A to B routing. Practical experience from attempting Cattle Pass on the wrong tide (as we once did) indelibly marks this detail as one not to forget. There are many “Cattle Pass” lessons that you learn to incorporate in A to B routing. This is local knowledge and it saves time, money, and lowers risk. Venture to a new area and local knowledge is gone.

Fortunately, wherever you’re going, somebody went there and wrote about it. Many blue water cruisers reference Jimmy Cornell’s World Cruising Routes. It’s a fine book for big picture routing and guidance on A to B routing, but it’s not a roadmap.

Our passage in April from Ascension Island to Barbados was 3,100 miles long. The small group of boats doing this passage referenced Cornell, and set out with the author’s advice on crossing the equator between 28 and 30 degrees west longitude. Crossing further west into northeast trade winds can make the Caribbean upwind and hard to reach. This advice has the downside of being into a wider band of ITCZ, meaning more squalls. Off the boats went, one by one, aimed at 28 degrees west. We chose a different route.

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Landfall: Ascension Island

In A to B routing, the longer or more complicated the route, the more days in advance I study weather and variables. For weeks I studied several different GRIB models. Day after day, trade winds were not northeast as Cornell said, but east north east and just fine for getting to the Caribbean. Investigating a route along the coast of Brazil, 900 miles west of Cornell’s route, I found reference to a strong current flowing northward along the coast. Fine wind, less lightning (narrower band of ITCZ), and positive current was too good to ignore. PredictWind’s routing algorithms (that’s our track in their viewer below, automatically generated with pings from our Iridium GO underway) in the Offshore app concurred, and bingo, we were off to the Brazilian coast. It was beautiful sailing with very few squalls, averaging 180 NM per day over 17.2 days. The “book route” took boats 5 to 7 days longer, experienced more squalls, and burned a lot more diesel. Budget sailors can get similar routing through FastSeas, a free/donation tool based on NOAA data for GFS and ocean currents.

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After this passage I happened to reread Slocum’s Sailing Alone Around the World. In 1898, Slocum sailed Spray on the same route along the coast of Brazil to reach the Caribbean in good time, noting, “the current, now at its height, amounted to forty miles a day.” Eighty-nine years later, Jimmy Cornell missed or disregarded this current. His book is still a great resource, but scenarios like this are a good reminder that it’s only one static resource.

From this lesson and others, here are six rules for A to B routing.

  1. Use multiple data sources.
  2. Schedules are inconvenient.
  3. When weather sources disagree, don’t pick one as best.
  4. Consider tidal and current flow.
  5. “Group think” weather analysis is always one opinion to many.
  6. Forecast accuracy varies regionally; compare forecasted and actual weather over time.

Efficient sailing will get you there faster, safer, and with less wear and tear. Just don’t confuse it with performance sailing! That can lead to soggy spinnaker and sour party mood.

This post was contributed by Jamie, who shares his more technical sailing experience from time to time. It’s really two legs on a three-legged stool, because routing is as important to efficient passagemaking as sail trim and sail handling…that post will have to come later.

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Cruisers should care about performance sailing

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There’s a problem: many cruisers think that sailing performance isn’t important. Hey, cruising is about slowing down, right?! But dismissing performance is poor seamanship. After some years of listening to cruisers disregard performance and gripe about slow passages, it dawned on me that confusion is to blame.

Our good friend William demonstrated this last year during a fun race in Madagascar. William is a good sailor with much blue water cruising experience. He doesn’t race, but his competitive side, or maybe his social side, was piqued by party and prizes to follow the competition. With his racing cap on he chose a bold spinnaker start while single-handing. It didn’t go well. The gun cracked and his spinnaker tangled, slipped, and dipped…he did not have a good race. On passage William is slow and deliberate when setting a spinnaker, a pace that isn’t very racer-like but ends with a performance boost. Had he stuck with this instead of confusing performance and racing, he would’ve had more to celebrate at the party.

To clarify this issue, let’s forget all about performance; and instead, talk about “efficient sailing.” A rabbit in a bunny suit is still a rabbit, so what’s the point? Comfort and safety come with avoiding or minimizing bad weather, and stress comes from contemplating a three day passage when weather windows only last for two days. Efficient sailing is getting from A to B with minimal effort. What could be more appealing to a cruiser than minimal effort!

Making landfall in Comoros, Indian Ocean

Making landfall in Comoros, Indian Ocean

Racing sailors are pedantic about sail trim. Constant adjustments can yield subtle gains that show when measuring against competitors. We’re not interested in subtle gains. Reasonable sail trim takes no more time than bad sail trim, but yields better speed with less wear and tear to sails.

For example, when reaching and running, a boom vang locks the boom from lifting and dropping due to changing wind pressure on the mainsail. This may seem insignificant, but not using a vang slows you down and will cost you money in repairing a mainsail chafed by rubbing against rigging.

Another example is headsail trim. Sheet blocks are often set for reasonable trim going upwind, which fine, except that most of the time cruisers aren’t sailing upwind. When using an upwind sheeting point for reaching and running, the upper portion of a headsail twists to leeward, spilling wind causing the upper leech to flap. A barber hauler is an easy way to trim the headsail correctly for broader wind angles. This gives a considerable boat speed boost that can be 10 miles and more per day.

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Both barber hauler and sheet are used for max efficiency at the wind angle

Racing sailors are well practiced at sail handling for fast transitions. Fast is usually not important or practical for short-handed cruisers, like our friend above. Efficient sail handling from a well setup boat, practice, and good crew communication reduces crew risks and equipment breakages.

Step one is setting up the boat to make sail handling easier. Cruising boats are usually reasonably well set up, but it takes time on the water to learn what works well and what needs improvement. Friction causes the most trouble. Friction makes you weak, and swear like a sailor. I installed a Harken furling system for cruising friends in Singapore. The next day they had words with me because furling was harder than ever. I went back to their boat and tested each furling line guide blocks. Only one of them actually turned, and the rest were easily fixed with fresh water and silicone spray.

Keep winches, blocks, and sheaves in good order. Watch for line chafe and metal fatigue. And give thought to unplanned sail handling events – they happen. When Totem was ghosting along the Pacific ITCZ, the heavy duty stainless steel pad eye securing the mainsheet to the boom sheared off. The part was less than a year old, and failed from slatting force. By chance, I had installed a webbing strop around the boom just in case such a thing happened. The mainsheet was reattached in just a couple minutes.

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Pacific, between Mexico and Marquesas. Bonus squall. Rather undesirable twist in the mainsheet….

Step two of efficient sail handling is matching sails to the conditions. This may seem obvious, but it’s common to see people raise the anchor and hoist full sails; then outside of the protected anchorage, bigger wind hits and they scramble to reef the main. This is almost like sport in the eastern Caribbean this spring watching boats poke out from the lee and into the channel between islands. Start the day with a weather forecast and a few moments of observation before getting underway, and don’t forget the impact of geography.

Once underway, reducing sail area is all about observation and timing. In 20 knots of true wind, I can reef our mainsail on my own in 2 minutes –less if more motivated by approaching squall. In 30 knots it takes at least twice as long. Monitoring wind speed and watching for obvious changes (like squalls) and subtle changes (such as increasing gusts) gives you time to adjust sails when it’s still easy.

Approaching the South African coast last November, we expected landfall 6 to 12 hours ahead of forecasted bad weather. With 20 miles remaining of the 1,000 mile trip, we were sailing in gentle conditions with a perfect sunrise, and feeling good. Then I looked up. Above a thin layer of clouds going our way, clouds whipped along in the opposite direction. Bad news: the southerly buster came early! Engine on, we prepared for strong headwinds. At 7 miles to go, wind was 25 to 30 knots on the nose and against the strong Aghulas current. Waves piled up with no gap between them, and our speed dropped under two knots bashing into them. It was a tedious few hours getting in, but each additional hour out there would have been worse.

This post was contributed by Jamie, who shares his more technical sailing experience from time to time. It’s really two legs on a three-legged stool, because routing is as important to efficient passagemaking as sail trim and sail handling…that post will have to come later.