Trim and stability/USR Flashcards
What is a vessel called that if it is loaded top heavy
Cranky or tender
What is a vessel called if she is loaded bottom heavy
Stiff
What is center of gravity G
point at which all the vertical downward forces of the weight of the vessel can be considered to act, or center of mass
What is center buoyancy B
point at which all the vertical upward forces of support (buoyancy) can be considered to act, or center of volume of the immersed portion of the vessel
What force causes a ship to move back to its original position
Movement of B
Define stability
The tendency for a ship to return to an upright position
What does a couple require
Two equal forces acting on a body in opposite directions and along parallel lines
The couple formed by G and B is?
Righting moment
Righting Arm is a?
Distance
If KG is less than KM what is ship
Stable
What is d
the vertical distance between initial location of G and and the position of the loaded or discharged weight.
What are you in danger of if the period of ocean waves and apparient rolling period are the same and how to fix
danger of capsizing
Change course or speed, or ballasting/ de-ballasting
What is the difference between + and - stability factors
Net stability factor
What are the 4 areas that are assessed on a USR
Personnel
S equipment and supplies on hand
R Equipment readiness
T Unit training level proficiency
What is GM
Metacentric height
What is KG
Keel to center of gravity
What is KM
Keel to height of the metacenter of transverse metacenter
VCG
Vertical center of gravity
What is GZ
righting arm
Who has exemption authority for USR
HQDA
How soon do you have to submit a report once on ground during a deployment
24 hours
How often do you have to submit a USR and what date is it due by.
Monthly and on the 15th
If a unit UIC ends if FF what report do they submit
Type 2
If a unit UIC ends if AA what report do they submit
Type I
USR’s are classified as?
Secret
what two points on a vessel almost wholly account for her stability
Center of G
Center of B
If KG is less then KM what does the ship have
Stable equilibrium
Another expression for height of the transverse metacenter is?
KM
BM is?
distance from center of buoyancy to transverse metacenter
What is synchronous rolling
how do you stop it
When period of ocean wave and apparent rolling period of the ship are the same
Change course, speed or both, ballasting/deballasting
If a ship has a negative GM what do you expect (G above M)
Able to list to either side
