Advanced Piloting Course (Coastal Navigation) Chapter 10 Review Educational Officer – Dave West Assistant Educational Officer – David Moberg – Instructor – Art Mollica United States Power Squadrons ®

2 APPENDIX A - WEEKEND CRUISE PART 5

3 x x x x x 1101 M0M GPS x 1151 GPS C 129M S D GPS 1300 C 020M S GPS Set 253M Dft 2.1 COG 009M SOG ) At 1400 you decide not to raft up with your friend. You leave “1” BELL at the entrance to Menemsha Basin and lay a course for BR C southwest of Lucas Shoal. Your speed is 10kn. Your GPS indicates a bearing of 020ºM. The wind has changed direction and is coming from the northeast and has increased in strength causing whitecaps in Vineyard Sound. You are having trouble holding the course. You suspect there is a current causing your boat to drift towards the southwest. At 1420 you can see the BR C to the northeast and you decide to stop and get a GPS Fix and calculate your set and drift. The 1420 GPS Fix position is L 41º24.3’N and Lo 70º46.7’W WptPan DBG29 VSRWNA QKHG1 VSBR MPG1 BBRR SPRR2

4 x x x x x 1101 M0M GPS x 1151 GPS C 129M S D GPS 1300 C 020M S GPS Set 253M Dft 2.1 COG 009M SOG ) At 1400 you decide not to raft up with your friend. You leave “1” BELL at the entrance to Menemsha Basin and lay a course for BR C southwest of Lucas Shoal. Your speed is 10kn. Your GPS indicates a bearing of 020ºM. The wind has changed direction and is coming from the northeast and has increased in strength causing whitecaps in Vineyard Sound. You are having trouble holding the course. You suspect there is a current causing your boat to drift towards the southwest. At 1420 you can see the BR C to the northeast and you decide to stop and get a GPS Fix and calculate your set and drift. The 1420 GPS Fix position is L 41º24.3’N and Lo 70º46.7’W a) Calculate the set and drift at b) Why is your drift more than calculated? 25c) What is your speed over ground? 25d) What is your course over ground? VSBR QKHG1 VSRWNA DBG29 1

5 x x x x x 1101 M0M0 x 1151 GPS C 129M S D GPS 1300 C 020M S GPS Set 253M Dft 2.1 COG 009M SOG C 018M S 10.0 XTE GPS 1447 Visual 1447 Course T = 256ºW V = 015ºW M = 271º 26) You take another GPS fix at 1435 L 41º 24.2’ N and Lo 70º 47.0’ W and continue towards R “28” Fl R 4sec BELL from the 1435 fix. Using the GPS cross track error (XTE) feature you stay within 0.25nm of your course. When you arrive at buoy R “28” Fl R 4sec BELL at your planned time of 1447 you make a decision to go to Buzzards Bay through Quicks Hole. You continue on a course to the buoy south of Quicks Hole and arrive at G “1” Fl G 4sec BELL at Speed is 10kn. What is the set and current strength at the middle portion of Quicks Hole at 1503? Use reference station Cape Cod Canal. C 271M S 10.0 WptPan 1106 GPS 1435 Course T = 003ºW V = 015ºW M = 018º QKHG1 BBRR VSRWNA MPG1 SPRR2 BBG7 VSBR VSR Visual

6 x x x x x 1101 M0M GPS x 1151 GPS C 129M S D GPS 1300 C 020M S GPS Set 253M Dft 2.1 COG 009M SOG C 018M S 10.0 XTE GPS 1447 Visual C 271M S Visual VSRWNA QKHG1 VSR28 VSBR MPG1 DBG29

7 C 271M S 10.0 C 066M S a) T = 051ºW V = 015ºW M = 066º 27b) T= 60D/S T= 60x6.4/13 T= 384/13 T= 29.5/30 min ETA c) T= 60D/S T= 60x3.5/13 T= 210/13 T= 16.2/16 min ETA c) Course T = 077ºW V = 015ºW M = 092º C 092M S 13.0 D C 252M S C 272M S M 1027 QKHG1 BBR8 BBBB BBR8 BBG13 QHR Visual 1521 BBG7 QKHBR C 000M S ) You arrive at Lone Rock BR 1 Qk Fl G at 1521 and change your course to a pre-determined GPS position of L 41º 31.8’ N and Lo 70º 44.5’ W northwest of Weepecket Island in 45’ of water. Speed is 13kn. 27a) What is the True course to the GPS WPT? 051º 27b) What is your ETA at the GPS WPT? c) Plot and label final leg of cruise to R “2” Fl R 4sec at entrance to Quissett Harbor. ETA at R “2” 1607

8 APPENDIX A - WEEKEND CRUISE FINISHED

Slide 9

Slide 10 Questions ? … Comments

Vectors have both speed and direction C105M S DR Course = course steered & boat speed At 1000 you depart position A on a true course of 090º with a boat speed of 5.0 knots. T-V-M = = 105ºM At 1050 your GPS position is B vs. DR position of C D = ST/60 = D = 5.0 x 50 / 60 = 4.16 = 4.2nm A GPS B Current = direction of flow (set) & speed of current (drift) Distance from C to B divided by lapsed time is drift Dft = 60D/T = Dft = 60 x 2.0 / 50 = 2.4kts and direction from C to B is set. C Actual Course = course over ground and speed over ground Distance from A to B divided by lapsed time is speed over ground SOG=60D/T = SOG = 60 x 3.1 / 50 = 3.72 = 3.7kts and direction from A to B is course over ground Set 240M Dft 2.4 COG131M SOG nm 3.1nm

Using known set & drift to determine compass course/course to steer At 1050 you depart position A for buoy at B with speed of 8.0 knots. Plot know Current effect = 2.4nm in 1 hour at 225º = starting point C Swing arc 8.0nm long from C to cross DR course line at D Direction from C to D is course to steer T – V – M = = 159ºM Replot & label this line from A to determine course is safe should current/drift change. Distance from A to D is speed = 8.9nm = 8.9kts ETA at B T=60D/S = T = 60 x 7 / 8.9 = = 47min = 1137 AB C105M S GPS Set 240M Dft 2.4 COG131M SOG 3.7 COG175M SOG 8.9 Set 240M Dft 2.4 CD C159M S 8.0

WP01 – buoy R N “2” near entrance to Blackfish CreekWP02 – buoy R N “2” near entrance to Shark River WP03 – Latitude N41º 44.0’; Longitude W71º 51.0’WP04 – buoy RG “D” Fl (2+1) R GONG WP05 – buoy R N “2” near entrance to Perkings Cove WP06 – center of compass rose WP07 – Latitude N41º 38.3’, Longitude W71º 46.5’ WP01 WP02 WP03 WP04 WP05 WP06 WP07

Plot and label your intended route, Leg 1 WP01 to WP02; Leg 2 WP02 to WP03; Leg 3 WP03 to WP04; and Leg 4 WP04 to WP05. 1) What is the total distance of your intended route? 2) What will be the initial compass heading from WP01 to WP02? WP01 WP02 WP03 WP04 WP05 WP06 WP07 C 355M C 102M C 061M C 174M D 10.9 D 6.3 D 3.5 D 8.9

Using WP07, what is the distance for the danger circle that will encompass the rocks near buoy G “5” Fl G 4sec GONG? Plot and label a crosstrack error along the first leg that will keep you clear of the rocks southwest of Channel Island. WP01 WP02 WP03 WP04 WP05 WP06 WP07 C 355M C 102M C 061M C 174M D 10.9 D 6.3 D 3.5 D 8.9 NLT 0.8 XTE 1.1 Stbd

Your intentions are to met friends for a raft-up and lunch at WP02. You need to determine the latest time on Saturday you can transit beneath the Tarr Bridge, a fixed span with a charted clearance of 35 feet above MHW and a charted depth of 10 feet at MLLW. For safety reasons, you want at least 38 foot of clearance. You will use the enclosed excerpts from the Bowditch Bay Tide & Current Tables for these calculations. Reference station is Perkins Cove West Jetty.

Tarr Bridge 3 Perkins Cove West Jetty 4 Jul 0548 H 1148 L H 0005 L H 1153 L L L L

You set your sails and at 0830 you pass close-abeam of WP01 on a starboard tack at 4.0kn. As is your practice, you plot your GPS position approximate every hour. Your times and positions along Leg 1 are: 09:27:40 L 41º ’N Lo 71º ’W; 10:30:15 L 41º ’N Lo 71º ’W; 11:30:12 L 41º ’N Lo 71º ’W; 12:26:18 L 41º ’N Lo 71º ’W. Plot and label each position. WP01 WP02 WP03 WP04 WP05 WP06 WP07 C 355M C 102M C 061M C 174M D 10.9 D 6.3 D 3.5 D 8.9 NLT 0.8 XTE 1.1 Stbd 0928 GPS 1030 GPS 1130 GPS 1226 GPS 0830 Visual

At 1230 you receive a VHF call from your friends advising you that they have anchored at position N41º ’, W71º ’. You start your auxiliary engine and make preparation to change course to join your friends. Remembering that practice is the only way to maintain your skills, you decide to plot your position using your radar. You note two distinctive radar returns at 1235 and identify them as buoys R N “2” at a range of 1.3nm and G C “1” at a range of 1.2nm. Plot your position and course to your friends. WP01 WP02 WP03 WP04 WP05 WP06 WP07 C 355M C 102M C 061M C 174M D 10.9 D 6.3 D 3.5 D 8.9 NLT 0.8 XTE 1.1 Stbd 0928 GPS 1030 GPS 1130 GPS 1226 GPS 0830 Visual WP Radar D 1.3 D 1.2 C 012M

You arrive at 1310 and raft-up. While discussing the morning’s cruise, you decide to determine your course and speed made good to your 1235 fix. What is your course made good? What is your speed made good? WP01 WP02 WP03 WP04 WP05 WP06 WP07 C 355M C 102M C 061M C 174M D 10.9 D 6.3 D 3.5 D 8.9 NLT 0.8 XTE 1.1 Stbd 0928 GPS 1030 GPS 1130 GPS 1226 GPS 0830 Visual WP Radar D 1.3 D 1.2 C 012M 1310 D = 7.8nm, T = 245minS = (60 x 7.8) / 245S = 1.91 = 1.9

You depart at 1400 for WP08 using your auxiliary engine at a speed of 6.0 kn. At 1445 you note the beacon on Channel Island abeam to starboard. Plot and label this position. You continue to WP03, arriving at As the predicted rain clouds are beginning to form you decide to abandon your plan and head directly for Perkins Cove. From past experience, you know the current along the intended route can greatly affect your course. You cut your engine and drift while you determine the new course. WP01 WP02 WP03 WP04 WP05 WP06 WP07 C 355M C 102M C 061M C 174M D 10.9 D 6.3 D 3.5 D 8.9 NLT 0.8 XTE 1.1 Stbd 0928 GPS 1030 GPS 1130 GPS 1226 GPS 0830 Visual WP Radar D 1.3 D 1.2 C 012M C 113M S M

You will use the enclosed excerpts from the Bowditch Bay Tide & Current Tables for these calculations. Reference station is Perkins Cove. What is the current set & drift at 1545?

Tarr Bridge 3 Perkins Cove West Jetty 4 Jul F F

Assume your speed made good from your 1400 position to WP03 will be your speed to WP05. From your 1530 position, what is your course to steer for WP05, taking into account your predicted current. WP01 WP02 WP03 WP04 WP05 WP06 WP07 C 355M C 102M C 061M C 174M D 10.9 D 6.3 D 3.5 D 8.9 NLT 0.8 XTE 1.1 Stbd 0928 GPS 1030 GPS 1130 GPS 1226 GPS 0830 Visual WP Radar D 1.3 D 1.2 C 012M C 113M S M COG 155M SOG 5.0 D = 6.7, T = 90min S = (60x6.7) / 90 S = 4.46 = 4.5 kn C 147M S 4.5 Set 2.0 Drf199M