Williamson Turn explained in details, A Navigating officer on the bridge should be familiar with the the action to be taken in case of a man-overboard situation and initiate the maneuver to recover the person at the earliest. In total, we have three types of turn, out of which Williamson’s turn is the most preferred as we can use it in any situation.
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What is Williamson turn?
The Williamson Turn is one of the preferred maneuvers in case of a person falling overboard to bring the vessel or small boats to its reciprocal course she was doing.
It is named after John Williamson of USNR, who invented and used it first to recover a person who went overboard.
The best thing about Williamson’s turn is that it brings the vessel on an almost reciprocal course, making it more effective at night or in restricted visibility. However, it can be used in any condition. Still, if it is daytime and clear visibility, an Anderson turn (single turn) or a Scharnow turn would be the quickest to reach the casualty.
Read: Orals Notes on Ships Radar
Williamson Turn Procedure – How to Execute Williamson’s turn in rescuing persons overboard
Steps to be followed as below.
- As soon as you came to know on bridge of Man Overboard.
- Put the Rudder hard over to the side of a casualty.
- Once your heading deviate 60° from the orignal course, put the rudder hard over to the opposite side.
- When you are 20° from the reciprocal course, put rudder amidships and steady on reciprocal course.
Williamson’s turn advantages and disadvantages
Advantages:
- It can be used in any situation.
- it brings the vessel back on its own wake (on a reciprocal course which is 180° from its initial course)
- Preferred if the exact time of the person overboard is unknown.
Disadvantages:
- Not as quick as Anderson’s turn (single turn) in an immediate action situation.
Williamson turn vs Single turn vs Scharnow turn
| Situation | Williamson turn | Single turn | Scharnow turn |
|---|---|---|---|
| Immediate Action Situation | Not as quick as the single turn in an immediate action situation and take the ship further away from the casualty, but it is effective. | In an immediate action situation will bring the vessel round in the quickest time | Not appropriate in Immediate action situation. |
| Delayed Action | Mostly it will take the ship to the casualty | Not Recommended | Not Recommended |
| Person Missing Situation | Recommended | Not Recommended | Recommended |
Few Questions Related to the topic:
Q1. what is a sailboat “Williamson” turn
Ans: Sailboat “Williamson” turn is same as a merchant vessel and above procedures to be followed.
Q2. which is faster for man overboard, the round turn or Williamson turn?
Ans: Round turn (also called Anderson turn and single turn) is faster in a MOB situation, but you need to consider the state of visibility and weather conditions while taking action.
Q3. If in Orals, the Surveyor asks to describe the Williamson turn maneuver
Ans: Tell him the Procedures, advantages, and disadvantages.
In this post we have only discussed about Williamson’s turn, for Single Turn (also known as Anderson and Round turn) & Scharnow turn you can refer out seperate post by clicking the link.