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19th May 2017 at 6:57 pm #2301
Is there any way to find out how long left of your Journey?
19th May 2017 at 10:26 pm #2303Theoretically, there is no way, because you don’t know what the winds have in store for you. But you can estimate. As a math guy here’s how I’d do it:
Calculate three numbers, your fastest time, your slowest time, and your expected time. You’ll have to make some assumptions:
1. Using the 38 footer, the hull speed (max speed) is 8.2 kts; for the Rose, let me guesstimate 9 kts, and transat, let’s say maybe 10 kts because it can get up on plane. (Folks, correct me if I’m wrong.)
2. You know the distance remaining. The game provides you with this data.
3. However, if the winds cooperate you might take a shortcut, or if they are adverse, you might have to go “the long way around.” Let’s assume you can use the distance given by the game.– For fastest time, divide the total remaining distance by your fastest possible speed.
– For slowest time, divide the total remaining distance by your slowest “believable” sustained velocity made good. Let me arbitrarily set this at 2 kts.
– For expected time, watch what speeds you’ve been able to achieve on the journey thus far, and use that for your speed. Then divide the total remaining distance by this speed to get remaining time.Example: I’m at the mouth of the strait of Juan de Fuca (close to Neah bay) and have laid out a course, with waypoints, up to Anchorage, AK. The remaining distance is 1350 nautical miles (nm).
Fastest time: 1350/8.2 kts = 164.6 hours, or 6.86 days.
Slowest time: 1350/2 = 675 hours or 28.13 days.
Expected time: I’ve managed only 2 kts so far, but that’s with light, contrary winds. Out in the pacific I expect to do more like 56 kts in the right direction at any time. So: 1350/5.5 = 245 hours, or 10.2 days.I’m an optimist, but this journey is very likely going to take me on the order of 10 days. THEN I can join in the racing action!
19th May 2017 at 10:31 pm #2304FWIW the formula for hull speed, in knots, is:
1.34*(square root of waterline length in feet)
I estimated the waterline length for the 38 footer to be about 37 feet. Plugging that in got me 8.2 kts.
The Rose has a similar waterline so I guesstimated its max speed at 8 kts
Transat is smaller…hence a smaller hull speed…but it goes up on plane so probably uses a different speed formula. I didn’t bother looking it up. ðŸ˜‰ This reply was modified 3 months ago by Puffin.
19th May 2017 at 10:47 pm #2306Thanks a lot for the Reply, do you only do one journey at a time?
19th May 2017 at 10:48 pm #2307Well, so far yes, but I’m gradually trying more and more stuff. TBH I’m waiting for the chance to have multiple instances of the same boat type for multiple journeys, that would be nice.

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