The COASTAL DRILLER has a trim of 2.13 feet by the stern. The draft at the forward draft marks is observed to be 8.0 feet. The draft at the center of flotation is __________.
• Trim is the difference between the draft forward and the draft aft • The center of flotation (LCF) is the point about which the vessel trims • Only a portion of the total trim will appear at the forward draft marks and a portion at the aft draft marks
• Think about whether the draft at the LCF will be closer to the forward draft, closer to the aft draft, or somewhere between them when the vessel is trimmed by the stern • Ask yourself: if the vessel has 2.13 feet more draft aft than forward, what does that say about the average draft around the LCF? • Consider whether the LCF is usually nearer to the middle of the vessel or at one end, and what that implies for the draft reading there
• Be clear that trim by the stern means the aft draft is greater than the forward draft by 2.13 feet • Remember that the draft at the LCF is related to the mean draft (average of forward and aft drafts) when trim is small and LCF is near midships • Check which answer choice is a reasonable draft value between a plausible forward and aft draft that differ by 2.13 feet
No comments yet
Be the first to share your thoughts!