Bobbing Along and Fuel Range

Crossing big oceans is rather monotonous so for some of you this post will capture the monotony of what a captain does on watch.

We left Valdviia April 1st and it’s now the 14th and we’re at S 29 05.741 W 98 42.000 which is I believe pretty much the middle of nowhere. If you’ve been following our app on the where we are page you can see several arcs and straight lines. Right now we are on a prolonged straight line heading at about 275 degrees true or almost due West. We plan to continue this heading due to favorable forecasted winds over the next several days and then race north west to Easter island (Isla De Pascue as the Chileans call it or Rapa Nui as the Islanders do) during the last day.

In our case we’ve been motoring at about 2,500 RPM’s, making a little over 5Kts and heading into about 10 Kts of wind on the nose. We could motor sail but we’d have to crack off at least 30 degrees and with the light winds we wouldn’t really be getting to our destination any faster (Velocity made good – VMG) even if we were sailing faster so we’re just taking our medicine and motoring directly into the wind. Our fuel gauge isn’t the most accurate but it says that we’ve used about 1 gallon per hour for the last 24 hours. Given our 210 gallon fuel tank capacity and our 5 – 5 gallon fuel jugs we can motor for (235 gal/24 hours a day or 9.8 days at 5kt’s per hour) 1,140 Kmiles without using the sails heading into a headwind in relatively calm South Pacific seas. So with just our main fuel tanks we have a conservative range of more than 1,000 Kmiles. I hope we never experience the monotony of motoring for 10 straight days but good to know we could if we were becalmed. If we were in no wind at all, we could likely make considerable better performance (fuel efficiency and speed) and if we had any favorable wind we could motor sail on a much more efficient heading.

However the goal is to sail and if the weather forecast holds today sometime we will be able to sail on a gentleman’s point of sail, broad reach, and turn the engines off and be one with wind and sea. If that works out we will have used about 50 gallons of fuel to go from Valdivia, Chile to Easter Island or about 2,000 miles albeit not a direct route. So the average fuel consumption on the passage will be about (2,000/50) 40 Kmiles per gallon. That would be a range of over 10,000 Kmiles for full tanks of gas plus jugs. Not bad mileage given we are transporting our home with all the conveniences of a top of the line rock star motor home which has I assume less than 1/10 the mileage.

If we do get good winds we can travel 175 Kmiles per day towards our destination which is about 7.5 Knots per hour. One a good day we should be able to get 200 Kmile of progress towards our destination or 8.3 Knots on average.

Given where we are now, assuming 150 Kmiles per day we should arrive at Easter island Sunday night at 8:30PM. If we do better and make 175 Kmiles per day we’ll be there by 7:15AM. My best guess is that we’ll drop anchor around noon on Sunday. Let’s hope we can make it sometime earlier so that we have the full day Sunday on Easter Island.