Here is the Mid Latitude formulae that I use occasionally
Note the dots are just to line everything up as it should be.
Mid Latitude Sailing Format
L1 . . . . . . . . . . . . . . . . , λ¹
L2_____________________ λ²____________________
L°’. . . . . . . . . . . . N/S . . DLO°’ . . . . . . . . . .E/W
L’ . . . . . . . . . . . . . . . . . DLO’
½L . . . . . . . . . . . . . . . . . P
LM . . . . . . . . . . . . . . . . . C
Dist . . . . . . . . . . . . . . . . CN
P = DLO’ X Cos LM
C = Tan¹(P/L’)
D = L’ / Cos C
L’ = D X Cos C
P = D X sin C
DLO = P / Cos LM
Your Course (CN) use the following Direction determined by the difference in latitude & Longitude.
N/E; Cn = 000+C
N/W;Cn = 360-C
S/E; Cn = 180-C
S/W;Cn = 180+C
Six easy formulae to use in mid Latitude sailing Have fun with this format.
And many times you will be faster than the dude plotting the positions on the chart to measure dist. and determine direction. That is if you practice with them.
P = Departure, C = Direction, D = Distance, L’ = Latitude in minutes,
LM = Mid Latitude, DLO = Difference in Longitude, CN = Your Course.