Items Affecting the Grounding of Ever Given

Question 1

What is Squat?

Answer 1

A decrease in under Keel Clearance with an Increase in Speed.

Question 2

When does Squat occur and HOW?

Answer 2

Occurs where the depth is less than twice the draft.

High Speeds.
Trim by the Head.

Worse in a Narrow Channel.

Question 3

How does squat impact?

Answer 3

Steerage.

In Fine line vessels - the stern goes down
In High Block Coefficient Vessels - head goes down.

High Block Coef is great than .7 Cb

Question 4

How can it be readily reduced?

Answer 4

By reducing speed.

Question 5

What should you take into account when calculating under keel clearance?

Answer 5

Height of Tide
Dynamic draft (taking into account vessels motions)
Heel
Squat (10% of Static Draft)
Margin of safety.

Question 6

How do you recognise Squat?

Answer 6

Increase Bow Wave.
Increase of Wake
Vibration.

Question 7

What effect does wind have on the ship?

Answer 7

Windage.

Affects the above water area of the ship. The centre of this point is known as W

The Centre of of rotation is the Pivot Point.

The difference determine how the vessel is affect by the Wind.