Seven knots? Yeah, it works. Summer? Check back later.
Quadra has been at sea nearly two weeks, and several days have been spent in marinas and protected harbors while gale-force northwesterlies roared out of the Pacific Ocean and smacked wetly into Vancouver Island and the mainland coast of British Columbia.
Rain is dripping generously as I write this morning, and more wet and wind are in the newest Canadian forecast.
There seem to be fewer boats along the Inside Passage than in previous years, but it is too early to know if it is the result of bad weather, the high price of fuel or because the cruising season along the passage usually comes to life in July.
One thing is certain: Pulling back the throttles pays dividends.
I began my test of speed reduction in Friday Harbor, Washington, the first stop on a planned six-week trip, where we filled the tanks carefully to the top with diesel costing $4.85. I then trimmed engine speed from 1800rpm to 1600rpm with a goal of maintaining 7 knots over the summer.
After35 hours and 240 miles I topped the tanks at the marina in Lagoon Cove, British Columbia. They took 115 gallons. After wearing out several pencil points and dozens of scraps of paper, I calculated that Quadra averaged 2.08mpg during the test period, burning 3.2 gallons an hour.
In the good old days – before we worried about the price of diesel – Quadra’s twin Ford Lehman engines together burned about 4½ gallons an hour, running at 1800rpm. Occasional use of the generator and diesel-fired furnace pushed the total to about 4.8gph. And the miles-per-gallon count would have been 1.45.
Had I operated at 1800 during the past two weeks it would have taken about 165 gallons to fill the tanks. I used 50 fewer gallons by slowing the engines to 1600! It appears fuel consumption has declined about 30 percent.
We’re about a quarter of the way along our planned route into northern B.C. So, there seems to be a chance Quadra will burn perhaps 200 fewer gallons of fuel as the result of 7-knot cruising. And that’s a savings of about $1,000.
The incentive to conserve is even greater in B.C. After converting liters to gallons and considering the U.S.-Canadian dollar exchange rate, the price of diesel in Lagoon Cove was a horrifying $5.80 a gallon.
Our average speed so far is 6.8 knots, a bit less than the 7 knots over- the- ground that was my target. I have exceeded the 1600rpm limit only once, when I was forced to crank the diesels to 1800 to avoid going backward in a rapids we reached a few minutes early.
Traveling at slower speeds is not a hardship in central British Columbia. The scenery is spectacular, with some of the mainland mountains still topped with snow. It was delightful to sit on the tall pier at the Shoal Bay marina at sunset. Several boaters gathered to watch the setting sun light up snowy, forested hills at the far end of Phillips Arm. I took some excellent photos and planned to include one with this report, but internet connections here at Lagoon Cove are DSL (darned slow and lethargic) and that can’t be done.
One wins this kind of testing by careful attention to tides and currents. We awoke at 0530 at Shoal Harbor a couple days ago and were underway at 0550 to take advantage of a north-flowing ebb. With the throttles at 1600, we enjoyed prolonged speeds of more than 9 knots for much of the six-hour trip, and the slowest noted was 7.2 knots at the conversion of Sunderland Channel and Johnstone Strait. Quadra ripped through Greene Point Rapids at 13 knots. Fortunately, it’s a laminar flow with few whirlpools and none of the overfalls found at Dent Rapids a few miles to the south. The express ride lasted only minutes.
There are other issues involved in running diesel engines at less than normal cruise speed. I’ll visit them later on.