NAVIGATION FORMULAES BY AMIT K SEN

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NAVIGATION FORMULAES BY AMIT K SEN

G R E AT C I R C L E S A I L I N G CALCULATING DISTANCE: Cosine AB = Cosine PA Cosine PB + Sin PA Sin PB Cosine P

CALCULATING INITIAL COURSE: Cosine A = Cosine PB Cosine PA Cosine AB Sin PA Sin AB

FINDING THE POSITION OF VERTEX: LATITUDE OF VERTEX: Cosine (Latitude) = Sin PA Sin A

LONGITUDE OF VERTEX: Tangent (D'long) = Cot A Sec PA …apply the d’long to initial longitude

FINDING THE LATITUDE OF A GIVEN POINT: Page 2 of 6

NAVIGATION FORMULAES BY AMIT K SEN

Tangent (Latitude) = Cosine (D’long) x Tangent (Lat. of vertex)

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C O M P O S I T E G R E AT C I R C L E SAILING CALCULATING DISTANCES USING NAPIER’S RULE

i)

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A V1

NAVIGATION FORMULAES BY AMIT K SEN

ii)

BV2

Sin (Middle Part) = Product of Cosine of Opposite Parts Sin (Middle Part) = Product of Tangent of Adjacent Parts

DISTANCE FOR V1 V2 (See Parallel Sailing)

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PA R A L L E L S A I L I N G

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NAVIGATION FORMULAES BY AMIT K SEN

Departure = D’long Cosine ( Latitude )

PLANE SAILING Sin

( Course ) = Departure Distance

Cosine ( Course ) =

D’lat Distance

Tangent ( Course ) = Departure D’lat

RHUMB LINE SAILING

CALCULATING INITIAL COURSE: Tan ( Course ) = D’long D.M.P

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NAVIGATION FORMULAES BY AMIT K SEN

CALCULATING DISTANCE: Cos ( Course ) =

D’lat Distance

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