ARC Report - Backup Systems
08/01/13 09:04 Filed in: Offshore sailing | Maintenance | Electrical
Atlantic Rally for Cruisers (ARC 2014 edition) is getting underway tomorrow Sunday November 23) and I know everyone there will be scurrying around with last minute jobs, enjoying the last parties and getting ready for the start line tomorrow morning. It is a VERY exciting time and Sheryl & I wish all the participants Fair Winds and Smooth Seas. We did the ARC in 2012 and thought it would be worth republishing summary of how systems worked for the boat in our “quite windy” running of the Atlantic Rally for Cruisers.
Before the start of the ARC in Las Palmas everyone was working on their boats and getting them ready - trying to prepare for all the conditions we would encounter in the 3000 mile crossing. Getting all the boats systems up and in top condition and preparing for all the contingencies. Trying to anticipate what could go wrong and how would we deal with the problems?
Here is a very un-scientific summary of how well systems, and backup systems, worked for boats on the ARC 2012.
Electrical Power systems
On this year’s ARC many boats reported problems with their electrical power. A number of boats had a malfunction with the main generator but were able to recharge the batteries from the engine. However most engine alternators produce less than you hope. The modern yacht does consume a lot of power. Similarly wind generators often do not work well when sailing downwind. And even the biggest solar array produces less than the typical modern boat uses on a passage. People with power problems had to turn off fridges, turn off autopilots (so crews were exhausting themselves hand-steering for thousands of miles !!!) and otherwise conserve power. The worst cases were boats that lost their engines and had no other way to generate power. In this case they finished the passage with no power left, in the dark!
What is your primary method of generating electrical power? Most of the larger ARC boats have a separate diesel generator, and many of the yachts less than 45 feet rely on the engine’s alternator to recharge the batteries. Some also have a reasonable capacity to generate electricity from Solar panels or Wind generators.
A number of people I spoke with did not know how much power they use. Many boats do not have a decent way to calculate how much they are adding/subtracting from their batteries. A quality power monitoring system is a must! Its essential to know how much power your boat uses on a passage. Refrigeration, autopilot, lighting, Nav instruments are all big users on passage and running 24-7 adds up! Some of the boats had left the cold northern European waters and were surprised how much more power the fridge consumed in a hot climate. Others just hadn’t done the math or worked out what they would need.
If you have a quality amp-hour meter such as Mastervolt’s Mastershunt - it will show what power you are using at any moment, total used since last full charge and other info such as the percentage of charge you have left in the batteries. You can use this to help estimate the power you will need for a passage. For more information on how to calculate an electrical budget click here.
On Distant Shores II we are using almost 300 amp-hours per day on passage. This mean we need to run the generator 3 hours per day to put it back in. If the generator quit we would need to run the engine 4-5 hours a day for the equivalent power. We could also cut back by shutting down our freezer and/or fridge, turning off our plotter etc and would reduce power use by probably 50%.
If your backup power is solar panels, you may find it will not cover typical power requirements while on passage. But it is a great backup system with the main drawback being much lower production on the cloudy days we had, especially at the beginning of the crossing this year.
Whatever you do - consider your power requirements carefully, and plan a backup strategy to generate power in the event your main system goes down.
Self-steering systems and autopilots were another area where ARC boats had a number of issues. Heavy conditions in the first week broke quite a few wind-vane steering systems. Quite a few boats found themselves hand-steering when they had an electrical problem and had to save power. On Distant Shores II we have a Raymarine autopilot connected to a robust Lewmar drive unit. It steered flawlessly the whole way right up to the finish line! The boat, a Southerly 49, is quite easy to steer with her twin rudders and has a well balanced helm so the motor isn’t straining and doesn’t draw very much power.
Here is a video showing the Raymarine Autopilot steering in some pretty big seas.
Sails, masts, downwind poles and other sailing systems were perhaps the area where most ARC boats had done the most thorough preparation and had thought out what to do in the event of problems. Only one boat I know of lost their mast and had to divert to the Cape Verde Islands for repairs. Although we saw many broken boomvangs, torn sails, and other rig problems on the dock in St Lucia, everyone seemed to have had a strategy and was able to continue on without too much difficulty. For more info on rigs and rigging see my previous blog below...
Many ARC boats were relying on water-makers to provide water for the crew. Compared to the average cruising boat with 2-3 crew onboard for an ocean crossing, the ARC boats had 5 or more - and this means providing more water for the crossing. A 37-footer with 7 crew, and a 40-footer with 9 on board will need quite a lot of water.
On board Distant Shores II we carry 545 litres of water, and had just the three of us (me, Sheryl and friend, Matt Heron) on the passage. I have installed manual foot-pumps at the galley and in the aft-heads, which we use at sea, and turned off the pressure water system for the crossing. This helped us easily conserve water, and also meant that if a leak developed in the system we wouldn’t dump all our fresh water! In the event, it was great having the foot-pumps. We did save water without feeling constrained and arrived at the finish with more than a third of a tank remaining. We switched the pressure system on whenever we needed it (when having showers for example) but mainly left it off for the passage.
A number of boats had engine problems - the most major issue being a propellor drop off, to simply being unable to get the motor started. But everyone with this problem was able to sail right up to the finish line and then accept a tow into the marina.
Many boats had problems with various communications systems - but since everybody had backups of some form, no one was seriously inconvenienced. For example, our SatPhone stopped receiving EMail for 4 days, but we were still in touch with nearby boats over the radio and we could also make phone calls so reports could still be filed, and the Yellowbrick tracker kept on working fine.
Communications upgrades! Probably nothing has changed so much in the last two years since our ARC 2012 as communications. New Satellite phones, the Iridium Go, Inreach and other devices have all come online. If anyone has tested these out please chime in with your thoughts and experiences.
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