Monday, February 19, 2018

Managing heavy weather at sea

Yesterday, we addressed a conference of about 100 cruisers at the Irish Sailing Cruising Conference. In 2008, on a crossing of the north Atlantic, we encountered six gales and managed to avoid one strong storm. What we learned then, we were here to share about our experience with storm management. The conference was summarized overall in Afloat magazine.

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Following is an overview of our talk:


Managing Offshore Storms

by Alex and Daria Blackwell

In 2008, Alex and Daria Blackwell left their jobs, loaded up their boat and sailed across the Atlantic. They cruised Maine and Nova Scotia in Aleria, their Bowman 57 cutter rigged ketch, before heading out to sea.  Alex, a master mariner and Daria, a licensed captain, had never crossed an ocean before but had been sailing for many years, including weeklong coastal passages, and did a great deal of preparation in advance.
But 2008 was an unusual year. Not only did the markets collapse around the world while they were out at sea, the North Atlantic had more heavy weather that year than would typically be expected. In the three weeks it took them to sail across from Halifax to Westport, they experienced six gales and managed to avoid one strong storm with potentially life threatening conditions. They gained a good deal of experience on that crossing and have since crossed the Atlantic twice more as well as having sailed to Scotland and Spain and along the west coast of Ireland many times, never again seeing the type of weather the North Atlantic had served up that year.
Since they survived, they were at the Irish Sailing Cruising Conference to share what they had learned.
Daria first gave a general overview of how to think about the factors that affect weather in the Atlantic. The ocean, being a conveyor belt for water, has currents circulating around it. The Gulf Stream brings warm water up the coast of the US that mixes with the cold Labrador current which brings cold water and ice down from the Arctic. That continues to Ireland as the North Atlantic Drift and then completes the loop with the Canary Current and North Equatorial current.
Above the Atlantic sits the Azores High, a stable bubble of airmass. Lows swoop down from North America and cyclones swoop up from tropical regions where they form to circle around the Azores High. Of course Hurricane Ophelia this year formed off the coast of Africa and headed directly North to Ireland reminding us that climate change is making weather events less predictable and more extreme.  The trade winds also circulate around this high pressure system creating the trade routes that, together with the currents, enable ocean crossings.
Despite being an oversimplification, understanding weather patterns during passage planning is essential. Many resources, like Passage Weather, are available today to assist with planning a passage in advance. After departure, however, other tactics are necessary.
It helps to develop a “weather eye” and keeping a log is important if something untoward happens but is also vital to forcing awareness of changing conditions. Timely response to changing conditions can mean the difference between safety and comfort or survival management.
The Blackwells worked with the legendary Herb Hilgenberg, now retired, who provided weather routing via SSB radio while they were underway. Herb helped them interpret the forecasts for their region and provided suggestions for the best routes to take advantage of the conditions and avoid undesirable ones. It pays to enlist the help of shore-based experts to help interpret the weather files, called GRIBS, one can download via SAT phone and SSB radio. There are many services available.
aleria message8When a weather window opened up, the Blackwells left Nova Scotia under thick fog in about 15 knots of breeze. The fog persisted along the entire coast of Newfoundland, which they never saw, until they crossed the Labrador Current. Until then, they had sailed under full sail. Afterwards, the wind started to build.

They have several rules they go by:
1.      Stay on the boat – that means never leaving the companionway to go on deck without being tethered to the boat. Sailing short-handed means that if someone goes overboard, the likelihood of recovery would be slim.
2.      The time to reef is when you first think about it. Often people make the mistake of waiting until conditions deteriorate when it becomes dangerous.
3.      Prepare in advance. Lack of preparation is an underlying factor in disaster.

When the squalls started, they followed their direction and speed on radar, but always made preparations in advance. Wind can go from 5 knots to 30 knots in seconds, and being caught unaware can result in a knockdown.

As the first gale approached, they had the following choices:
1.      Sail on
2.      Deploy a sea anchor or drogue
3.      Run with the wind
4.      Lie a-hull
5.      Heave to

As every boat is different, the Blackwells had experimented with various methods and determined that heaving to in a storm situation to let the storm pass over more quickly was their best bet on Aleria.  Sailing on in a storm is what racers do. This can cause a lot of stress on rig and crew. As cruisers the Blackwells don’t subscribe to such discomfort.
Deploying a sea anchor puts great stress on deck hardware and can be dangerous to deploy on a pitching deck and difficult to retrieve afterwards. In addition, there is evidence that the stretching and contracting of the rode in these extreme circumstances will cause internal abrasion in the fibres of the rope, potentially leading to catastrophic failure.
Running with the wind under bare poles or storm sails would require hand steering to manage the mountainous seas, and that would be difficult with only two people. The motion of the wave cause the boat to yaw severely from side to side. If the boat tends to surf down the waves it is possible that the bow will become buried in the wave trough which would cause the boat to pitch-pole.
Lying ahull in which all sail is removed and the boat is left to its own defences was deemed most at risk of the vessel broaching and getting swamped in massive seas.
They had experimented with heaving to under benign conditions and decided that this would be their best option.
Heaving to on many boats is achieved by tacking after reducing sail and not releasing the headsail sheet. The headsail is therefore backed and counteracting the force of the main sail. The helm is lashed or locked to windward. The boat settles down on an angle of about 60 degrees off the wind sailing at about 1-2 knots, slipping sideways, creating a slick upwind and smoothing the seas. When hove to, a degree of stability and calm is achieved that is astounding.
The Blackwells sailed on through the first gale in which wind was in the range of 35 knots gusting over 40. Their boat did well under staysail and mizzen alone. When the wind built to more than 40 knots and the sea state built to 30 feet with cresting waves and foam in the second gale, they opted to heave to. For 36 hours, the gale raged overhead while they read books. After the gale, they released the headsail sheet and then tacked through to get back on course. The key here was to time manoeuvres with the seas. “We noted that waves in this gale were coming in sets of 3 of about 20 feet and the 4th would be an outlier of 30 to 40 feet. So we timed our tack for just after the fourth wave to give us the best chance of not broaching if caught beam on.”
But the gales were unrelenting. They sailed through another and then opted to heave to again. Half way through that gale Daria called out “I can’t take it anymore, let me off at the next stop.” When Alex remarked that they had forgotten to bring cookies along, Daria took to baking peanut butter cookies, it was that calm aboard.
Daria explained that a quote by Donald Hamilton summed it up for her, “Being hove to in a long gale is the most boring way of being terrified I know.” Having a good library aboard made all the difference in the world.
On yet another occasion, heaving to may not have sufficed. Herb advised the Blackwells to turn back and sail west for a day to allow a strong storm to pass their track. With yet another gale approaching Alex being frustrated did not heed the warning and sailed into the worst conditions they had experienced yet, confirming that indeed the weather routers know what they are doing. Aleria hove to for a third time before finally heading into Clew Bay.
The Blackwells explained that heaving to is not just useful in storm situations. Heaving to can also assist with:
·         Reefing or dropping the mainsail
·         Making repairs in less challenging conditions
·         Adding fuel to the tanks
·         Having lunch in more peaceful conditions
·         Rendezvousing with a dingy
·         As a viable MOB manoeuvre

The most important consideration is to practice under benign conditions to determine how your boat responds. Some vessels, like catamarans, heave to best with one sail alone.
Several members of the audience confirmed the effectiveness of heaving to. One experienced sailor told a story of being caught in a storm on a delivery where the owner refused to heave to. He finally relented when conditions became unbearable and now swears that it was the best thing he’s ever learned.
An RNLI lifeboat crew member informed the group that he had just been at a seminar in which the rescue helicopter service now request sailboats to heave to on port tack if a rescue is underway because their equipment is deployed from the starboard door. They have determined that heaving to is the most effective means by which to stabilise the vessel and keep the mast from getting caught up with their gear.
Participants were left thinking about their options and planning their next opportunity to practice heaving to.

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Alex is Rear Commodore for Ireland of the Ocean Cruising Club, a Committee member and newsletter editor of the Irish Cruising Club and Committee member of Mayo Sailing Club. Daria is Rear Commodore of the Ocean Cruising Club. Alex and Daria are co-authors of Happy Hooking the Art of Anchoring and Cruising the Wild Atlantic Way.



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