STABILITY Flashcards
Stability criteria for all ships?
- initial GM NLT 0.15m
- Area under GZ curve NLT 0.055 m-r up to 30 degrees, 0.09m-r up to an angle of 40 degrees or angle of flooding whichever is lower.
- 0.03 m-r between 30 and 40 degrees or angle of flooding whichever is lower.
- Max GZ to occur NLT 30 degrees and be at least 0.2m in height (tankers prefer excess 30 degrees but more than 25)
Stability Criteria for timber deck cargo?
- Initial GM NLT 0.05m (alternative criteria states 0.1m)
- Area under the curve NLT 0.08m-r up to 40 deg or angle of flooding.
- Righting lever GZ NLT 0.25m at 30 deg or greater
- GM should be positive after correcting for FSE (tanks, absorption of water ice accretion)
Stability criteria for grain ships?
- List due to grain shift NMT 12 deg
- Area between heeling arm curve and righting arm curve upto 40 deg or angle of flooding NLT 0.075 m-r
- Initial GM 0.30m
- Void average depth 15cm
- grain is assumed to move in a pattern such that the voids change shape and the grain surface moves 15 degrees to the horizontal.
Freeboard assignment
What is in your damage stability booklet
What is GT, DWT, NT, LT SHIP
GT. Moulded volume of enclosed spaces of the vessel used to calculate manning, safety rules, reg fees, port dues. Total internal volume of the vessel
NT. moulded volume for revenue earning spaces (cargo). Used to calculate port dues.
DWT. Difference between displacement and light ship. How. Ich weight a ship can carry safely. Including everything.
LT SHIP. weight of ship when complete including perm ballast spares lube oil and working stores but not cargo crew fw bunkers or boiler water
Displacement. Weight x density
Inclining experiment why is it’s required and how will you do it?
Find the initial KG and create the vessels stability booklet, using the vessel CoG and hydrostatic details. Lightest condition, vessel secure for sea as if going out, including crane etc. approved weight moved t9 9ne side check list and same for other side and check the weight. Even keel.
