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16th April 1976

16th April 1976

Cargo vessel 0455 GMT41 52N144 14WPass vessel0455 GMT42 25N147 40W Co. 075T, Spd 24ktsCargo vessel to rendezvous with passenger vessel at sunrise.

Calculate GMT of sunrise, Rendezvous position and Course and speed required to steer by Cargo vessel.LMT 40 05212 25 - 03

SRise LMT 0518

LIT 0951

GMT 1509

Start 0455

Diff 1014

Speed x 24

Distance 245.6 nmLMT 40 05213 28.6 - 05

SRise LMT 0516

LIT 0929

GMT 1445

Start 0455

Diff 0950

Speed x 24

Distance 236.0 nm

DLat = Dist x Cos Co = 245.6 x Cos 75 = 63.56596 = 1 3.6 N

M. Lat = 42 56.8

Dep = DLat x Tan Co = 63.3 x Tan 75 = 237.23139DLong = Dep / Cos M Lat = 237.23139/ Cos 42 56.8 = 324.09181 = 5 24.1 E

Start 42 25.0N 147 40.0 W

DLat 1 03.6N DLong 5 24.1 E

1st Approx 43 28.6N 142 15.9WDLat = Dist x Cos Co = 236 x Cos 75 = 61.08129 = 1 1.1 N

M. Lat = 42 55.5

Dep = DLat x Tan Co = 61.08129 x Tan 75 = 227.95848DLong = Dep / Cos M Lat = 227.95848 / Cos 42 55.5

= 311.31415 = 5 11.3 E

Start 42 25.0N 147 40.0 W

DLat 1 01.1N DLong 5 11.3 E

2nd Approx 43 26.1N 142 28.7W

Cargo vessel

41 52.0N

144 14.0WRV Position43 26.1N

142 28.6W

01 34.1N

001 45.4E

DLat94.1 N

DLong 105.4 E

M Lat42 39.05

Dep= DLong x Cos M Lat

= 105.4 x Cos 42 39.05

Dep= 77.52131

Tan Co= Dep / DLat

= 77.52131/ 94.1 = 39.48232Course= N 39.5 EDist = DLat / Cos Co.

= 94.1 / Cos 39.48232Dist= 121.9 nm

Speed= 121.9 / 9h50m

Speed = 12.4 kts


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