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Show the full working of all calculations including the formulae used and logarithm calculations. Illustrate where appropriate with a diagram.

225. A yacht sails due W. for 200 nm. from position Lat. 40º 30.0 N., Long. 009º 00.0 W.  Calculate what Long. she should reach.

 

∴ Position of Yacht after 200 nm due West = LAT. 40º 30.0’ N Long. 13º 23.0’ W

 

226. Calculate how many miles there are in 1º of Long. in Lat. 42º 00.0 N.

227. Calculate the length of the parallel of Lat. 35º around the Earth.

228. If a yacht sailed 250 nm. due E. and changed her Long. 8º, calculate Parallel of Lat. she sailed a Long.

229. Find Courses and Distances by Mid. Lat. Sailing calculation (not by Traverse Table): –

a. Venice in Lat. 45º 22.0N Long. 012º 30.0 E. to Corfu in Lat. 39º 50.0 N. Long. 19º 50.0E.

      To find Distance:               Formula: Distance = d.lat x sec.Co.

∴ Distance = 464.41 nm.

b. Majorca in Lat. 39º 30.0 N. Long 02º 45.0 E. to Oran Lat. 35º 45.0 N. Long. 00º 37.0 W

∴ Distance = 276.4nm.

 

c. Nassau: Lat. 25º 08.0 N. Long. 77º 30.0 W. Bermuda Lat. 32º 34.0 N. Long. 64º 50.0 W.

= Course 056º 30’ (T)

        To find the Distance:           Formula: Distance = d.lat x sec Co.

∴ Distance = 803.5 nm.

230. Calculate by Mid. Lat. Sailing (not by Traverse- Table) the D.R. Position after sailing: –

a. 400nm. Cse 127º T. Rhodes (Lat. 36º 07 N., Longitude 28º 10 E.) to Israel

b. 500nm. Cse 226º T. St. Maarten (Lat. 18º N., Long 63º 05 W.) to Curacao.

c. 1000 nm. Cse 300º T. Cape Farewell-New Zealand (Lat.40º30.0S., Long 172º 50.0 E.) to Australia.

231. Find the Course and Distance by Traverse Table only between the following places:-

a. Fishguard Lat. 52º 01.0 N. Long. 04º 58.0 W. Dublin Lat. 53º 21.0 N. Long. 06º 04.0 W.

b. Bridlington Lat. 54º 05.0 N. Long. 00º 10.0 W. Cromer Lat. 52º 56.0 N. Long. 01º 18.0 E.

c. Needles L/Ho. Lat. 50º 40.0 N. Long 01º 36.0 W. Guernsey Lat. 49º 28.0 N. Long 02º 30.0 W.

232. Find the D.R. Position by Traverse Table only, after sailing: –

a. 380 nm. on Course 087º T. Malta (Lat. 35º 54.0N., Long 14º 30.0 E.) to Greece.

∴ Position of Yacht after 380 nm = Lat 36º 13.9’N Long 22º 19.4’ E

b. 150 nm. on Course 200º T. Naples (Lat. 40º 48.0 N., Long 14º 15.0 E.) to Sicily.

∴ Position of Yacht after 150 nm = Lat 36º 13.9’N Long 13º 08.4’ E

c. 500nm. on Course 145º T. Hong Kong (Lat. 22º 10.0 N., Long. 114º 20.0 E.) to Manila.

233. By Traverse Table – Course to Steer from Falmouth;Lat. 50º 08.0N., Longitude 05º 00.0 W. to Jersey in Lat. 49º 10.0 N., Longitude 02º 12.0 W., allow estimatedset and drift of the tidal stream over the run of 250º @ 18 miles.

234. A Motor yacht sailed from Dover (Lat. 51º 06.0 N., Long. 001º 18.0 E.) with her log set at Zero, on Course of 210º T., When her log read 18.0, off Dungeness, she altered course to 250º T., and when the log read 49.0, off Beachy-Head, she altered course to 280º T. Find by Traverse Table the yacht’s D.R. Position when the log read 66.0’.

Vessel D.R. Position @ Log 66.0’ = Lat 50º 42.8’ N Long 00º 08.8’ W

What would her E.P. (E.P.) be at this time if the set and drift of the tidal stream over the run was 235º, at 10 miles.

Vessels E.P. @ Log 66.0’ = Lat 50º 37.1’N Long 00º 21.7’W with allowance for Tidal Stream 235 (T) @ 10.0 nm.