NAVIGATION FORMULAES BY AMIT K SEN

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GREAT CIRCLE SAILING

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 dlong to initial longitude

FINDING THE LATITUDE OF A GIVEN POINT:

Tangent (Latitude) = Cosine (Dlong) x Tangent (Lat. of vertex)

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COMPOSITE GREAT CIRCLE SAILING

CALCULATING DISTANCES

USING NAPIERS RULE

i)A V1

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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PARALLEL SAILING

Departure = Dlong Cosine ( Latitude )

PLANE SAILING

Sin ( Course ) = Departure

Distance

Cosine ( Course ) = Dlat

Distance

Tangent ( Course ) = Departure

Dlat

RHUMB LINE SAILING

CALCULATING INITIAL COURSE:

Tan ( Course ) = Dlong

D.M.P

CALCULATING DISTANCE:

Cos ( Course ) = Dlat

Distance

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