NavList:
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Re: Silicon Sea: Leg 74
From: Dan Hogan
Date: 2001 Jun 17, 09:54 EDT
From: Dan Hogan
Date: 2001 Jun 17, 09:54 EDT
On 16 Jun 2001, at 17:01, Michael Wescott wrote: > > Our last Running FIX(13d 37.8'N 68d 10.5'W) 16:30:29UT @XXX.XXX > > We were headed for Aruba Gap(13d 50.0'N 70d 00.0'W). > > > On 02/06/2001 @XXX.XXX7 Nmi from our RFIX we made a course > > change at the Aruba Gap (13d 50.0'N 70d 00.0'W) waypoint. Our destination is > > Cristobal, Panama(09d 23.0'N 79d 55.0'W). We are anticipating a transit of > > the Panama Canal. > > > Var 8.0dW, Dev 1.0dE . Current Set 275.0d Drift 1.5 Kts. Speed 10.4Kts. > > > > 1) What is the the TC and Distance from Aruba Gap(13d 50.0'N 70d 00.0'W) > > to Cristobal, Panama(09d 23.0'N 79d 55.0'W)? > > -- --------------------------------------------------------------------- > > dLat = 9d23.0' - 13d50.0' = -4d27.0' = -267.0 > dLo = -(79d55.0 - 70d00.0') = -9d55.0' = -595' > dep = -595 * cos 12 = 582.0 > TC = 270.0 - atan(267/582) = 245.4 OK > > 2) What is the Compass Course(CC)/Course-to-Steer? > > -- ----------------------------------------------- > > CC = 245.4 + 8.0 - 1.0 = 252.4 > Correcting for current (on plotting sheet) gives > course 242.5T or 249.5C > > > Since our turn at Aruba Gap(13d 50.0'N 70d 00.0'W)We have been sailing in a > > steady wind and clear skys. > > > At 05:16:28ZT @XXX.XXX > > Speed 10.4 Kts, TC 245.5d. > > > 3) What is the 05:16:28ZT DR position? > > -- ----------------------------------- > > We're in the GMT-5 zone centered at 75d W > > 04-06-2001 10:16:28UT > -02-06-2001 06:46:28UT > ====================== > 2 days 03:30:00 = 51.5 hr > D = 51.5 * 10.4 = 535.6 > dLat = 535.6 * cos 245.5 = -222.1 = -3d42.1' > Lat = 13d 50.0'N - 3d 42.1' = 10d 07.9'N > > dep = 535.6 * sin 245.5 = -487.4 > dLo = -487.4/cos 12 = 498.3' = -8d 18.3' > Lon = 70d 00.0'W + 8d 18.3' = 78d 18.3'W > > DR: 10d 07.9'N 78d 18.3'W OK > > > We take the following sights: > > > Body UT/GMT Hs > > > Fomalhaut 10:17:22 47d 14.7' > > Deneb 10:17:56 51d 52.0' > > Altair 10:18:00 59d 18.2' > > Wow! only 4 seconds between sights. :-) Thanks for commenting ;^) > > > Vega 10:18:46 37d 34.3' > > Venus 10:19:33 33d 20.0' > > > > 4) What is the position FIX? > > -- ------------------------- > > Using NAO sight reduction table and plotting sheet > about > > 10d 29.0 N 78d 30.5W OK. > > > Speed 10.0 Kts. Var 5dW, Dev 1.5dE. Current Set 100.0d Drift 0.7 Kts. > > > 5) What is the TC and Distance to Cristobal(09d 23.0'N 79d 55.0'W) > > from the FIX position? > > -- ---------------------------------------------------------------- > > Using plotting sheet TC = 232 D = 106 OK > > 6) What is the ZT and Date of our ETA at the Cristobal waypoint > > (09d 23.0'N 079d 55.0'W)? > > -- ------------------------------------------------------------ > > Allowing for current, SOG is about 9.5 which is about > 11:03 sailing time. That's 21:21 UT or 16:21 ZT same day > 4-Jun-2001 OK > -- > Mike Wescott > Wescott_Mike@XXX.XXX Dan Hogan dhhogan@XXX.XXX