NavList:
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Re: Silicon Sea: Leg 76
From: Dan Hogan
Date: 2001 Jul 10, 7:56 AM
From: Dan Hogan
Date: 2001 Jul 10, 7:56 AM
On 9 Jul 2001, at 14:06, Michael Wescott wrote: > > We then motor to the Isla Flamenco and anchor at(08d 55.2'N 79d 31.6'W) to > > do the final trip planning, servicing, and provisioning the boat. We will > > motor from our anchorage to abeam the Light at Isla San Jose(08d 10.5'N 079d > > 15.0'W). Speed 8.3 Kts. Our departure is planned for sunrise on 24/06/2001. > > > > 1) What is the Zone Time(ZT) of sunrise at our anchorage? > > What is the UT/GMT time of Sunrise? > > -- ------------------------------------------------------ > > Anchorage at 08d 55.2'N 79d 31.6'W. Sunrise on 24-Jun-2001 will be > shortly after 0541 LMT. LMT is 4d 31.6' West so we add about 18 min to > get ZT. And for GMT we add 5 hours. A close enough answer is > > 0600 ZT (GMT+5) > 1100 GMT > > Wow, sitting in the Pacific further east than where I'm sitting now > (Columbia, SC). Correct to both :^) > > 2) What is the TC and Distance from Our anchorage(08d 55.2'N 079d 31.6'W) > > to abeam of Isla San Jose Light(08d 10.5'N 079d 15.0'W)? > > -- ----------------------------------------------------------------------- > > Reading directly from the chart (or plotting sheet, in this case) > > C = 160T D = 47.6 YEP. > > It is late in the season and the North Pacific storms are beginning so we > > elect to bypass the Galapagos Islands. We will follow the recommendations in > > Ocean Passages For The World and in World Cruising Routes and on departing > > Isla San Jose Light(08d 10.5'N 79d 15.0'W) we will head for a Mid-Ocean > > Point(MOP) at (03d 00.0'N 110d 00.0'W). > > Why so far south? To avoid the storms? Don't we risk light winds so far > south? Avoid the North Equatorial Counter Current, also follow and favorable winds. > > 3) What is the TC and Distance to the MOP at (03d 00.0'N 110d 00.0'W) > > from Isla San Jose Light(08d 10.5'N 79d 15.0'W)? > > -- ------------------------------------------------------------------ > > Using M.P.: C = 260.4T D = 1861.9 > Using M.L. (5d30'): C = 260.4T D = 1862.6 > Using GC: IC = 262.1T D = 1861.5 OK > > From the MOP(03d 00.0'N 110d 00.0'W) we head to make landfall on the > > Southwest coast of Hawaii(19d 30.0'N 154d 45.0'W). We have two alteratives > > depending on current and weather, either a Great Circle Course or the Rhumb- > > Line course. > > > > 4) Calculate the Rhumb Line TC and Distance to landfall. > > Calculate the Great Circle initial course and Distance to landfall. > > -- ------------------------------------------------------------------- > > Rhumb Line (M.P.): C = 290.5 D = 2820.2 > Great Circle: IC = 294.2T D = 2801.1 > > > 5) To the nearest tenth of a day, what are the total days enroute from our > > anchorage at Isla Flamenco to the Southwest coast of Hawaii as our plan > > is layed out? Sailing Speed 9.5 Kts, motoring Speed is 8.3 Kts: > > > > Isla Flamenco (08d 55.2'N 79d 31.6'W) > > Isla San Jose Light(08d 10.5'N 079d 15.0'W) > > Mid-Ocean Point(MOP) at (03d 00.0'N 110d 00.0'W) > > Southwest coast of Hawaii(19d 30.0'N 154d 45.0'W) > > -- ------------------------------------------------------------------------ > > For planning purposes we'll use the longest (Rhumb Line) and slowest (8.3 > knot, 199.2 nmi/day). > > Leg 1: 47.7 > Leg 2: 1861.9 > Leg 3: 2820.2 > ============= > Total 4729.8 which is 23.7 days Planning wise OK. Q5 asked for 9.5 Kts. > > Having a 6 person crew and water consumption at 1.5 US Gal/day per person. > > > > 6) What is the expected water consumption for the trip to Hawaii? > > -- -------------------------------------------------------------- > > 213.3 gal OK, for your planning. > > 7) Estimating 3lbs of food per day per person what is the total weight > > in food for the trip? > > -- ------------------------------------------------------------------- > > Twice the water. 426.6 lbs. Ditto as above. > > -- > Mike Wescott > Wescott_Mike@EMC.COM Dan Hogan WA6PBY C27 "Gacha" dhhogan@verimail.com Nav-L Page: http://www.wa6pby.com