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Gross Tonnage Formula:
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Gross Tonnage (GT) is a dimensionless index calculated from the total enclosed volume of a ship. It represents the overall size of a vessel and is used for regulations, safety rules, and registration fees rather than actual weight.
The calculator uses the Gross Tonnage formula:
Where:
Explanation: The formula calculates a vessel's gross tonnage based on its total enclosed volume, with the K coefficient adjusting for the logarithmic relationship between volume and tonnage measurement.
Details: Gross Tonnage is crucial for ship classification, determining port dues, safety regulations, manning requirements, and maritime insurance. It provides a standardized measure of ship size that's recognized internationally.
Tips: Enter the total enclosed volume in cubic meters. The volume must be a positive value greater than zero for accurate calculation.
Q1: What's the difference between gross tonnage and deadweight tonnage?
A: Gross tonnage measures total enclosed volume, while deadweight tonnage measures carrying capacity (weight of cargo, fuel, etc.) a ship can safely carry.
Q2: Why is there a logarithmic component in the formula?
A: The logarithmic term accounts for the fact that larger ships have relatively less tonnage per unit volume than smaller ships due to structural efficiency.
Q3: How is gross tonnage used in maritime regulations?
A: It determines safety equipment requirements, minimum crew size, port fees, canal transit charges, and compliance with international maritime conventions.
Q4: Does gross tonnage represent actual weight?
A: No, gross tonnage is a measure of volume, not weight. One gross ton equals 100 cubic feet (2.83 cubic meters) of enclosed space.
Q5: Are there different tonnage measurement systems?
A: Yes, the International Tonnage Convention (ITC) of 1969 standardized gross and net tonnage calculations, replacing older systems that varied by country.