NavList:
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Re: Silicon Sea: Leg 75
From: Dan Hogan
Date: 2001 Jun 21, 10:02 PM
From: Dan Hogan
Date: 2001 Jun 21, 10:02 PM
On 21 Jun 2001, at 9:57, Michael Wescott wrote: > > Our last position FIX was (10d 30.0'N 78d 30.0'W) at 10:16:28UT @ > > 04/06/2001. We are bound for Cristobal, Panama(09d 23.0'N 79d 55.0'W). Our > > Estimated Time of Arrival(ETA) at Cristobal is 16:34:28ZT @ 04/06/2001. > > > > 1) What day of the week of our arrival? > > -- ------------------------------------ > > Monday (4 Jun 2001) OK > > On VHF we call the Panama Canal Transit Authority on Channel 16 for > > instructions. We are required to fly the Panamainian Courtesy Flag from the > > Starboard spreader and the quarantine flag from the port spreader. > > > 2) What color is the quarantine flag? > > -- ---------------------------------- > > Yellow or "Q" Right > > We anchor overnight, since the Panama Canal Authority requires 24 hours > > notice. We are anchored in an area known as the "Flats" until we can > > approach for inspection. > > > After our approach approval and customs clearance on the next day we begin > > the process of making the preparations for transiting the Panama Canal. The > > mooring fee is $00.50 per foot to each greater foot per night. > > > 3) What is the mooring fee for Silicon Sea per night? > > -- -------------------------------------------------- > > $24.50 (based on a 49' LOA). OK. They actually charge the next foot greater, I'm told. > > We are required to have 4 dock lines 125 feet long with a three foot eye on > > one end. And strong attach points. > > > 4) Can we make these lines from a 500 foot roll of 3/4' line? > > -- ---------------------------------------------------------- > > Nope. Aside from the fact I always mess up the first eye, cut it off > and throw it away, a 3' eye adds at least 4' to 5' so each line would > require about 130' of rope. Right > > The actual canal transit takes about 12 hours to complete. However, > > completing the Admeasure, getting Cruising Permits, clearing Customs and > > Immigration inspections can take 3 to 14 days for a small boat. It will take > > Silicon Sea until June 14 to complete the transit she is on the Pacific side > > of the Panama Canal. > > What's the toll these days? I'd heard somewhere that they were going > to increase it for yachts. As of my last check, the transit fee for boats 50' and under is $500.00 plus a buffer fee of $700.00 that is returned after the completion of the transit, if you don't damage the canal. Plus the charges for the various inspections. > > 5) In what direction does the Panama Canal run from the Atlantic Side to > > the Pacific side? > > -- --------------------------------------------------------------------- > > South East. Right > > While moored and waiting to complete the required inspections before > > transit. The Skipper worked the following two celestial problems. > > > DR position(09d 24.6'N 79d 56.7'W) on 11/06/2001. > > > No. 1 UT/GMT Body Hs > > > 23:41:30 Arcturus 51d 58.7' > > 23:42:10 Procyon 29d 24.3' > > 23:43:05 Spica 57d 44.3' > > > 6) What is the FIX position for SR No. 1? > > -- -------------------------------------- > > The LOP's form a nice triangle with the DR position in the center and > about 1.0 nmi from each LOP. > > Did you mean for the IC to be -2.5' rather than the -1.5 given? Yes. I forgot to change it in the problem Note. > > Fix: 9d 24.6'N 79d 56.7'W > > > These are the same sights as listed in Q6. But this time all numbers are to > > be ROUNDED to the nearest whole number. If you are using a calculator or > > Computer program round any numbers that are accessible, ie. Lat, Lon, Hs, > > GHA and Dec, to work the sight reduction and plot both FIXes. DO NOT ROUND > > TIME. > > > UT/GMT Body Hs > > > 23:41:30 Arcturus 51d 59.0' > > 23:42:10 Procyon 29d 24.0' > > 23:43:05 Spica 57d 44.0' > ` > > 7) What is the FIX position for SR No. 2? > > -- -------------------------------------- > > This set of LOP's gives a slightly larger triangle. The fix shifts > north and east. > > Fix 9d 26'N 79d 56'W > > > Now compare the two FIXes. > > The fixes are close together, about a 1.5 miles apart. The biggest > difference is in the LOP's for Arcturus. Rounding errors accumulated > to another mile, whereas the differences in the LOP's for the other > sights was due almost entirely to the change in DR. > > On the whole the second fix was easier to calculate and lost little > in the way of accuracy. The calculations that contributed most to > the difference was the rounding of Ha. My point. For sailboats traveling at the speeds we do. it it a waste of effort and time to do SR to greater than the nearest minute. > > > -- > Mike Wescott > Wescott_Mike@EMC.COM Dan Hogan dhhogan@verionmail.com