Design Report Guided Missile Submarine SSG(X) - AOE - Virginia ...

SSG(X) Design – VT Team 3 Page 59
4.3.3 Weights
Ship weights are grouped by SWBS. The components list was obtained from the Model Center optimization.
The weight for each component was compiled into an Excel spreadsheet. In addition to the weights, their centers of
gravity (vertical and longitudinal) were entered. These centers of gravity were estimated using the ship’s
arrangements. The weights and centers of gravity (CG) were used to find the lightship load and CG of the
submarine. To make sure that the submarine was balanced, the longitudinal CG (LCG) needed to be as close to the
longitudinal center of buoyancy (LCB) as possible. In order to facilitate this need, the centers of all of the
components were taken with reference to the LCB of the submarine. The LCB of the ship was taken to be at the
volumetric center of the buoyant volumes of the submarine. The LCB turned out to be 119 ft. from the bow. A
summary of the weights by SWBS code and the lightships weight are listed in table (insert ref). The complete
weights spreadsheet is provided in the appendix (whatever).
Table 38 - Lightship Weight Summary
SWBS Group Weight (lton) VCG (ft) LCG (ft)
100 1220.51 -0.29 3.66
200 334.58 -2.55 -50.05
300 44.59 -2.40 -33.40
400 159.74 1.52 76.46
500 178.12 1.09 -0.62
600 57.65 0.73 9.52
700 49.89 0.55 32.03
8 (Lead) 315.00 -15.00 26.98
Total (LS+8) 2360.08 -2.34 3.80
4.3.4 Load Conditions
The arrangements drawings, weights spreadsheet, and the variable loads are used in creating the extreme
loading conditions in the different water densities that the submarine will encounter. The loading conditions used
are the Normal Condition, Light #1, Heavy #1, Heavy #2 (mines), Heavy Forward #1, Heavy Forward #2, and
Heavy Aft. Table 39 illustrates each of the loading conditions and the water density used for each loading condition.
Once the loading conditions were positioned on the plot with the polygon, the next task was to get all of the points
inside of the polygon. To do this, ballast tanks were changed, components were moved, and lead was added and
taken away. Figure 92 shows the final equilibrium polygon with all of the loading conditions inside of it.
Table 39 - Variable Load Summary
Group Items Ship Normal Light Heavy Heavy Heavy Heavy Heavy
Synthesis Condtion (Diesel) (Diesel) (Mines) Fwd #1 Fwd #2 Aft
(N)
(Diesel) (Diesel) (Diesel)
No Arctic Water Density
(lbf/ft 3 )
64 64 64.3 63.6 63.6 64.3 64.3 64.3
Condition A A
Disp. Sub A’
MBT (ltons) MBT’
Weight to
Submerge
Ws’
1, 2, 3 Fixed Loads: WF10+
Normal
crew and effects, Wsew+
ballistic missiles,
sanitary, lube oil,
0.1·WF46
4 Gases: Nitrogen, dl WArgon+ Full None Full ½ to ¾ ½ to ¾
Oxygen,
Hydrogen, Argon
WO2+
WH2
full; max
fwd
moment
full; max
aft
moment
5 Torpedoes,
Wvp Full None Torpedoes Mines Aft Aft Fwd
Missiles, Mines,
and and Expended Expended Expended
Ammunition
Missiles Missiles