Formulas

Question 1

What is the formula for wind-force in pounds?

Answer 1

Wind force =.004 x W x v^2
W = windage in square feet
V= wind speed in knots
Wind-force is expressed in pounds

Question 2

Formula for windage on the beam? On the bow?

Answer 2

W(abeam) = LOA x D - LBP x mean draft
W(on the bow) = B x D - B x draft forward
LOA = Length overall
LBP = Length between perpendiculars
B = Breadth, molded
D = Depth, molded

Question 3

What is the formula for force of current on the beam?

Answer 3

C = f x L x d x v^2
C = current load in short tons
L = length in feet at waterline
D = mean draft
V = current speed in knots
Expressed in tons

Question 4

What is the equation for squat in meters? In feet?

Answer 4

S (meters) = Cb x V2/100
S (feet) = Cb x V2 / 30
Cb = block coefficient
S = squat
V = speed in knots
Pg 88 Shiphandling for the Mariner - Macelrevey

Question 5

What is the equation for blockage factor?

Answer 5

Blockage factor Fb = b x T / B x H
Where:
b = breadth of the ship
T = deep draft of the ship
H = Height of tide
B = breadth of the channel

Question 6

What is the standard formula for Squat

Answer 6

MacElrevey 87-88 S = Cb x V2 / 30 Where: S = Speed Cb = Block Coefficient V2 = Knots

Question 7

What is the formula for wind force per 1,000 m^2? How do you find wind in meters per second if you are given knots?

Answer 7

Force (tonnes) per 1,000 m^2 = V^2 / 18
V = wind speed in knots / 2

V = wind speed (meters / second)

Pg 43 Shiphandling for the Mariner - Rowe

Question 8

What is the formula to find approximate windage?

Answer 8

Windage (in m^2) = Length Overall x Max Freeboard

Pg 43 Shiphandling for the Mariner - Rowe