When circumnavigating in a power boat, does it matter if you go east or
west around?
Do the winds or the currents make one direction favorable to another?
I'm talking about a voyage in a boat such as Idlewild's.
When I leave from Seattle, I need to know if I should take a right at San
Fran and head to Honolulu, or keep going south towards the canal...
thanks!
Mel
When circumnavigating in a power boat, does it
matter if you go east or
west around?
A quick Google search found the following list of solo
circumnavigators Sail) showing most go westward toward
the setting sun:
http://www.joshuaslocumsocietyintl.org/solo/solotable.htm
Why? Currents and winds. The Willard Boat Owner's
Group
(http://groups.yahoo.com/group/WillardBoatOwners/)
recently discussed the 1987 journey of a Willard 36
from San Diego to Hawaii (2275 nms). An archived 1987
letter from the boat's owner to Willard Marine
explained he averaged 6 knots and burned under 350
gallons at 0.9 gph. This was difficult to believe -
the W36 would have to do around 5.5 knots to burn
under 1 gph.
However, after consulting Visual Passage Planner
software (www.digwave.com), the owner's claim is
credible (VPP is an electronic version of the Pilot
Charts with historical wind/current/storm patterns for
all oceans, all months. This is the same information
Jimmy Cornell based much of his World Cruising Routes
book upon). Assuming a 5.5 knot boat at 0.9 gph, the
August weather patterns predict a bump in speed to
just under 6 knots - and burn 389 gallons, very close
to the owner's 1987 claim.
Going the opposite direction - Hawaii to San Diego -
is a different matter. The VPP model estimates the
trip takes 2-days longer, average speed drops to 5.1
knots and total fuel burn increases ~15%.
Bottom line: time of year is important as Scott Bulger
suggests, and for equatorial circumnavigations,
westward appears to be the better direction.
Peter
www.SeaSkills.com