Light Ship Survey
A ship changes and grows, much like a living organism. If you aren’t careful, that ship can get overweight. Small changes to the light ship weight add up and eventually compromise your stability. This limits cargo capacity, tank capacity, and your vessel’s range. A light ship survey checks the current light ship weight and center of gravity for your ship.
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A light weight survey is typically required by your regulatory authority. It provides a lower cost alternative to a full stability test with incline experiment. The light weight survey determines three specific items:
- Light ship weight
- Longitudinal center of gravity (LCG)
- Transverse center of gravity (TCG)
The survey cannot calculate the vertical center of gravity (VCG). That requires an incline experiment. Light ship surveys normally require 2 – 3 days, depending on the ship size. A light ship survey should be a regular part of your occasional vessel maintenance. Think of it as a health check on your vessel stability. Large changes here signal the need for an incline experiment and further stability analysis. Best to learn about it now, when you can set the schedule for future changes.
DMS utilizes computer systems to log our light ship survey. This allows us to perform the calculations as we go. You get preliminary results on the day of the survey. We then perform quality control back at our office. Final results from the deadweight survey arrive a few days after the survey. No waiting for people to transcribe paper into computers. At DMS, we work fast.
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