6.7 Stability and WT Integrity - 6.7 Stability and WT Integrity

Question 1

Stability Reference Points

Answer 1

Picture

Question 2

Center of Buoyancy

Answer 2

Follows the waterline
picture

Question 3

Center of Gravity

Answer 3

Point at which all weights could be concentrated

COG moves towards a weight addition

COG moves away from a weight removal

Question 4

Righting Arm

Answer 4

Distance between the forces of buoyancy and gravity

Question 5

When is stability always reduced?

Answer 5

Gravity is high
Gravity is off centerline

Question 6

Danger Angle

Answer 6

One-half the angle of heel corresponding to the maximum righting arm value

Question 7

Free Surface Effect

Answer 7

Occurs when a compartment or tank is only partially flooded/filled
When the ship rocks due to the gravity of the liquid shifting constantly

Question 8

Free Communication Effect

Answer 8

Compartments must…
be open to the sea
be partially flooded
be off centerline

Question 9

X-RAY/ YOKE /ZEBRA Fittings

Answer 9

Special permission required, must be logged in the DC Closure Log if opened during the corresponding Condition of Readiness

Question 10

CIRCLE X-RAY / CIRCLE YOKE / CIRCLE ZEBRA Fittings

Answer 10

May be opened with out special permission to transit, inspect, and access vital spaces

Question 11

Dog ZEBRA Fittings

Answer 11

Set for Darken ship

Question 12

WILLIAM Fittings

Answer 12

Vital sea suctions, ventilation, and maintenance fittings for mobility

Question 13

CIRCLE WILLIAM Fittings

Answer 13

Access and ventilation fittings

Question 14

X-RAY Condition of Readiness

Answer 14

In homeport, in fair weather, normal working hours

Question 15

YOKE Condition of Readiness

Answer 15

At sea / inport during peacetime, outside of normal working hours

Question 16

MODIFIED YOKE Condition of Readiness

Answer 16

Fittings below the waterline are closed, above the waterline may be left open to improve accessibility and habitability

Question 17

ZEBRA Condition of Readiness

Answer 17

Set during General Quarters, entering and leaving during wartime, when in danger

Question 18

MODIFIED ZEBRA Condition of Readiness

Answer 18

CO may wish to set a modified material condition ZEBRA to provide higher survivability stance than condition YOKE but less restrictive than ZEBRA

Question 19

CIRCLE WILLIAM Condition of Readiness

Answer 19

Set to prevent contamination in a CBR environment

Question 20

Metacentric Height (GM)

Answer 20

Distance between the COG and the meta center.

Prime determiner for stability

Large GM = Fast roll period
Small GM = Slow roll period

Question 21

Righting Arm

Answer 21

The distance between the forces of buoyancy and gravity

Perpendicular line drawn from the COG to the point of intersection on the force of buoyancy line

Question 22

How to we utilize Compartmentalization on ships?

Answer 22

• Decks
• Platforms
• Levels
• Bulkheads