WIDE BASED SEMI-SUBMERSIBLE VESSEL

Abstract: A wide based semi-submersible vessel comprising a watertight buoyant deck (52), a plurality of stability columns (20) extending downwardly and outwardly from the deck, means (30) connected to the lower ends of the stability col­ umns for providing a wide buoyant base, and means (64) for discharging and taking on ballast.

Description: WIDE BASED SEMI-SUBMERSIBLE VESSEL The present invention relates to a semi-submersible vessel having a novel arrangement of buoyancy pontoons or footings, stability columns and deck to provide a vessel with improved stability characteristics. A vessel constructed in accordance with the present invention is also particularly suitable for use in ice-infested waters. The conventional semi-submersible vessel is the product of an evolution in design. During the initial offshore exploration for and production of hydrocarbons, drilling technology was based on shore-side experience. The supporting offshore platforms were either fixed structures or towers built on pilings, or a barge or caison which was floated out to the offshore site and then flooded to rest on the subsea bottom. When further exploration placed wells farther offshore, the increasing water depth required improved structures. The barge or caison approach evolved into a floating structure having submerged buoyant pontoons or footings, stability columns extending upwardly through the water surface, and a non-buoyant deck on top of the stability columns. The deck supported a drilling rig and other exploration equipment. To minimize the vertical movement of the drilling rig, the cross-sectional area of the stability columns was minimized at the water-line level. The resulting vessels are collectively called semi-submersibles. While the configuration of offshore supporting structures was evolving to accommodate deeper water, the well locations were also extended into more hostile environments. The first offshore wells were drilled in protected waters close to shore. When storms threatened, personnel were evacuated until the danger passed. Today however the frontiers of offshore drillng are located in remote waters far from the shore. The distances from shore prohibit rapid evacuation in stormy weather, and the offshore platforms are exposed to increasingly severe storms since the waters are not protected by land masses. Because the conventional design of semi-submersibles is a product of evolution through conditions different than those experienced today at remote and often hostile sites, the stability characteristics of the offshore platform do not best accommodate the conditions imposed on the vessel by operation in such remote environments. Conventional semi-submersibles are deballasted when severe weather strikes to ensure a sufficient air-gap between large waves and the bottom of the deck structure, and to increase the height of the working platform. However, such deballasting has an undesirable effect of exposing more surface to the wind and waves while actually raising the center of gravity and reducing the metacentric height. There are three facets to the stability phenomenon; initial, large angle, and damaged. The initial stability of a vessel is the familiar concept of metracentric height (GM). It represents the vessel's resistance to heeling over small angles, up to 50 to 100, and is essentially a characteristic of the vessel's waterplane. The technique of quantifying large angle stability differs from measuring the GM. To measure the stability, the righting arms of the vessel are calculated over a range of heel angles. The area under the resulting curve represents the energy the vessel can absorb. Lastly, damaged stability measures the ability of the vessel to withstand tank or compartment flooding. Though more subjective then the other aspects of stability, a thorough analysis reveals the vessel's ability to survive within the design criteria. Conventional semi-submersibles lose initial stability when deballasting. Because ballast water is located low in the pontoons, the vertical center of gravity of the vessel (VCG) is raised when it is pumped out, and the GM is reduced. The present rational behind such procedure in adverse weather is that the large angle stability is improved by providing more reserve buoyancy to resist large angle heeling as well as increasing the angle to which the vessel may heel before downflooding occurs. Also, when the operators wish to move the semi-submersible, the draft is reduced until the pontoons surface. The intermediate condition before the waterplane is dramatically increased with the emergence of the pontoons often presents a situation with marginal stability. The simplistic answer to the problem would be to increase the beam of the vessel until the minimum GM was acceptable. Unfortunately, too much initial stability is also detrimental. The high accelerations resulting from extreme GM at the operational draft would both degrade the crew and require additional steel throughout the structure to handle the inertial loadings. Further, the entire deck structure itself would increase due to the larger spans encountered between the stability columns. Another problem occurs in exploiting offshore ice-infested areas where masses of ice continuously form during certain parts of the year. These ice masses may include sheets of ice having thicknesses of eight feet thick or more which may have substantially thicker "pressure ridges'. These ice masses are not stationary and may move several hundred feet per day under the influence of surface winds and currents. Obviously, these moving ice masses develop substantial forces which, in turn, may be destructive to objects lying in the path of the ice masses. In accordance with the present invention, there is provided a wide based semi-submersible vessel comprising a deck, a plurality of stability columns extending downwardly and outwardly from the deck, means connected to the lower ends of the stability columns for providing a wide buoyant base and means for taking on and discharging ballast to increase and decrease the draft of said vessel. The present invention solves the stability problem by angling the stability columns outboard from the deck structure to a wider supporting base, and by making the deck structure itself watertight and effective at large angles and when damaged. The wide effective beam at shallow drafts provides greater GM while the angularity of the columns limit the stability at deep drafts and does not require additional deck steel. The buoyant deck structure contributes to the large angle stability when immersed and provides reserve buoyancy in the event of catastrophic damage, i.e., the loss of a stability column. The resulting wide based semi-submersible vessel is superior to the conventional design of semi-submersibles. The GM over the range of drafts can be optimized such that the stability never degrades below minimum values. At the same time, the angularity of the columns prevents the CM from becoming excessive. In all cases, the large angle stability of the wide based semi-submersible vessel exceeds that of the conventional straight-legged configuration. When damaged, the wide based semi-submersible vessel better withstands flooding resulting in greater residual righting energy and less danger of downflooding. It is contemplated that the angularity of the columns with respect to the vertical can be within the range of greater than Do to less than 900. A semi-submersible vessel is particularly suitable for use in ice-infested waters. The strength of an ice mass in compression is substantially greater than in flexure or bending. In accordance with an aspect of the present invention ballast is discharged and taken on when desirable to bring the stability columns into contact with an ice mass. As the vessel rises the outboard surfaces of the downwardly and outwardly extending columns would exert an upward or bending force against an ice mass located outboard of the vessel to break such mass. Conversely, lowering the vessel causes the inboard surfaces of the columns to exert a downward bending force against ice located beneath the deck. Ballast may be continuously taken on and discharged to cyclically lower and raise the vessel when ice conditions are severe. FIG. 1 shows a side elevational view of a semi-submersible vessel constructed in accordance with the present invention; FIG. 2 shows a top plan view of the vessel of FIG. 1; FIG. 3 shows an end elevational view of the vessel of FIG. 1, with a drilling rig; FIG. 4 is a schematic side elevation view of a baseline vessel having vertical stability columns; FIG. 5 is an end elevational view of the vessel of FIG.. 4; FIG. 6 is a top plan view of the vessel of FIG. 4; FIG. 7 is an end elevational view of an embodiment of the present invention wherein the stability columns are angled 100; FIG. 8 is an end elevational view of an embodiment of the present invention wherein the stability columns are angled 150; ; FIG. 9 is an end elevational view of an embodiment of. the present invention wherein the stability columns are angled 200.; FIG. 10 is an end. elevational view of an embodiment of the present invention wherein the stability columns are angled 300; FIG. 11 shows curves representing characteristics of vessels with differing stability column angularity; FIGS. 12A-12F show curves of righting arm versus heel angle for the straight legged baseline vessel, and for the wide based semi-submersible vessel configurations in accordance with the instant invention; and FIGS. 13-23. show examples of typical semi-submersible vessel configurations which are modifiable in accordance with the present invention to provide a wide buoyant base and thereby improve stability of such vessels. With reference to FIGS. 1-3, there is shown a wide based semi-submersible vessel having a watertight buoyant deck 10 supported on three stability columns 20 which extend continuously downwardly and outwardly from the bottom of each outboard side of the deck 10. The three stability columns 20 on each side of the vessel are connected to a respective elongated pontoon 30 to provide a wide buoyant base for the vessel 30. As shown in FIG. 3, an example of a structural truss arrangement 40 is provided between each of the opposing three pairs of stability columns 20 and the bottom of the deck 10 to ensure structural integrity of the vessel. Each one of the three structural truss arrangements 40 has a transverse member 42 interconnecting an opposing respective pair of stability columns 20, a vertical member 44 extending upwardly from the center of the transverse member 42 to the bottom 46 of the deck 10, and a pair of diagonal members 48, 50 extending upwardly from the center of the transverse member 42 to the bottom 46 of the deck 10. The structural truss arrangements may take any form or shape so long as structural integrity of the vessel is maintained. The deck 10 has a transverse center portion 52, a sponson portion 54, 56 extending downwardly from each side of the center portion 52 of the deck 10. The inner surface 58, 60 of each of the sponson 54, 56 extends downwardly and outwardly from the center portion 52 of the deck 10 at an angle which may correspond to the downwardly and outwardly extending three stability columns 20 on each side of the vessel. The bottom 46 of the deck 10 is constructed to be structurally sufficient to withstand "wave-slap" loads from the sea, and the entire deck is constructed to be structurally watertight up to the level of the main or weather deck 62. Sea water ballast, fuel oil, and drilling water are suitably located in tanks 64 located in each of the buoyancy pontoons 30 and in tanks 66 located in each of the stability columns 20. Spaces for propulsion motors and shafting, thrusters, are located in the lower portions of the buoyant pontoon 30. Dry bulk storage for drilling mud and cement may be located in the upper tanks 68 of the stability columns 20 and in the deck 10. Machinery spaces, storage spaces, workshops and living accommodations are also located in the deck 10. The main or weather deck 62 may be used for additional storage space, pipe racks drilling rig and other drill equipment and machinery, additional accommodations, dedicated or specialized shops and equipment, such as fire fighting. The stability columns 20 are inclined away from the vertical at an angle specifically choosen to enhance the stability characteristics of the vessel, which can be in the range of greater than Do to less than 900. At the normal operational waterline 80, the effective beam of the vessel, and hence the stability of the vessel, is increased without increasing the span and weight of the deck structure, the increasing effective beam increases the stability of the vessel. When deeply ballasted, the low location of the ballast water in the ballast tanks 64 of the buoyancy pontoons 30 lowers the center of gravity ofthe vessel, and even though the effective beam of the vessel is reduced, the stability of the vessel is not impaired. As shown in FIG. 3, the twin-sponson 54, 56 arrangement forms with the bottom 46 of the deck 10 with an inverted "V" shape between the sponsons 54, 56. Such configuration of the bottom 46 of the deck 10 improves the vessels capacity to resist the impact of "wave-slap" when deeply ballasted while minimizing detrimental interference of the deck 10 at operational draft. Further, because the deck 10 is watertight throughout, the buoyancy of the deck 10 will prevent capsizing in the event-of catastrophic damage, flooding, or other accident. Following are the results of a study performed to demonstrate the advantages of the present invention: CONSTRAINTS The semi-submersible hull form used to study the effect of the proposed configuration was based on the MSV "IOLAIR". The "IOLAIR" consists of twin pontoons supporting six stability columns under a buoyant deck. The pontoons are "ship-shape" in that they have a faired bow forward and a ship-form stem supporting a ducted propeller. The stability columns are rectangular in cross-section with radiused corners. In order to highliqht the effect of wide based semi-submersible vessel configuration, several simplifications were applied to the "IOLAIR" form as shown in FIGS. 4-6. Primarily, all elements, pontoons 92 and stability columns 94, were regarded as rectangular in section without radiuses, and all six stability columns 94 were given the same dimensions. Further, the forward and aft ends of the pontoons 92 were considered blunt without any fairing. The forward columns were considered flush against the forward perpendicular and the aft columns similarly located against the after perpendicular. The dimensions of both the pontoons 92 and the stability columns 94 were chosen to be thirty-six feet by twenty-four feet. The columns 94 were oriented with the long dimension fore and aft, and the pontoons 92 with the short dimension vertically. The centerline of the columns 94 were aligned with the center of the respective pontoon. The buoyancy of trusses (not shown) between the columns 94 was ignored. Around the top of the stability columns 94 ran a tight box beam 90, of the same width as the columns and depth as the deck structure of the t'IOLAIR,'1 forming a ring of reserve buoyancy. Though not sufficient to support the entire weiqht of the vessel, this minimum of reserve buoyancy was purposefully chosen to conservatively represent the effect of a buoyant deck without overpowering the contribution of the angular columns. In the final design, the entire deck is to be watertight. The principal particulars of the baseline vessel of FIGS. 4-6 were adapted from the "IOLAIR" as well. The length of both the pontoons 92 and the main deck 90 (they are flush at each end) became 99.97m (328 feet) and the beam over the main deck 90 became 47.55m (156 feet). The depth of the vessel was held constant at 30.48m (100 feet) with the buoyant deck 90 occupying the top 4.88m (16 feet). From the straight-legged baseline vessel of FIGS. 4-6, the study varied the angularity of the stability columns over the range of 00 to 300 by rotating the columns outboard from the bottom of the buoyant deck l4.63m (84 feet) above the baseline. Thus, the deck width and all other principal dimensions were held constant. As the stability columns were angled outward, the offsets were adjusted to maintain a constant cross-section perpendicular to the axis of the column. Because the angularity increased the effective width of the column, the inboard offset was reduced keeping that outboard constant. The pontoons were not rotated with the stability columns but they were located further apart to preserve their orientation to the outboard edge of the columns. A design displacement of 20,000 mt was chosen for the straight-legged baseline vessel resulting in a nominal 15. 24m (50 feet) design draft. However, as the columns were angled outward, the displacement increased somewhat. In order to be consistent, the design displacement for the wide angled configurations was increased to maintain the design draft. The vessel 's VCG at the design displacement was held to be 13.71m (45 feet) above the baseline for all configurations studied. For the other drafts considered, the difference in displacement was attributed to the addition or removal of saltwater ballast. In all cases, the ballast was taken from-or added to the volume within the pontoons; at a VCG of 3.66m (12 feet). Therefore, the vessel's VCG at each draft considered was calculated and incorporated into the evaluation. The resultant shifts in VCG were large over the range considered and thus important. The effect of any consumption of stores and/or supplies would be to reduce the topside weight and thus improve the stability. Therefore, alternative loading conditions were not investigated. Consumption of fuel would either be compensated for by adding ballast within the pontoon, which would not change the stability, or by allowing the vessel to rise out of the water, which would be the same as the deballasting situations calculated. HULLFORM The wide based semi-submersible vessel configurations with stability columns angled 10 , 150, 200 and 300, are shown in FIGS. 7-9 and 10, respectively. The exact angle of the stability columns correspond with the nominal figure for the 30 wide based semi-submersible, however, for the case of the configurations with intermediate angles, the actual angle is slightly different than the nominal. Because the characteristics of vessels with columns closer to the anticipated optimum were of importance, the offsets chosen were selected as more realistic, i.e. even numbers. The resulting column angle was rounded-off to become the nominal angle. In any case the difference is quite small, less than one degree. The hydrostatics for the vessels with stability column angles of DO, 200 and 300 are presented in Appendix I. INITIAL STABILITY FIG. 11 presents the initial stability of the wide based semi-submersible vessel. The figure shows the GM along the horizontal axis corresponding to any draft along the vertical axis. The different curves represent the characteristics of vessels with differing stability column angularity; ranging from 00 to 300. As can be seen at the design draft of fifty feet, the stability increases rapidly for increasing column angularity from l.37m (4.5 feet) of GM with 00 to 9.45m (31 feet) with 30 . At lighter drafts, the stability varies over a greater range. For vessels with less than about 100 column angularity, the stability actually diminishes; whereas vessels with greater angularity, the stability increases. In the very light condition before pontoons surface, the straight-legged baseline vessel experiences a negative GM, but the 300 wide based semi-submersible vessel has a CM exceeding 30.48m (100 feet). The characteristics are less divergent at drafts deeper than 15.24 (50 feet). Because all the vessel configurations rotated the stability columns about the same point, the bottom of the buoyant deck, their waterplanes become more similar as the vessels ballast down. When the bottom of the buoyant deck is about to be immersed, the only differences in stability are due to the slight variations in ballast onboard giving slightly different VCGs. At these drafts, the GMs are about 4.57 to 5.18 (15 to 17 feet) for all configurations studied. The GM was calculated using the drawings of FIGS. 4-10 and hydrostatics presented in Appendix I hereof at the 7.32m (24 feet) and 25.6dim (84 feet) waterlines, the drafts just before the pontoon break the surface and just before the buoyant deck is immersed. At the other drafts calculated, the GM was obtained from the righting arm curves described in the next section for the vessels with column angles of 0 , 20 and 300. For the intermediate angles of 100 and 150, the GM was calculated using the drawings and hydrostatics at drafts of 7.62 and 15.24m (24 and 50 feet), and the balance of the curve was obtained by fairing the lines between the cases which were fully calculated. FIG. 11 does not present the GM for the conditions with the pontoons exposed or with the buoyant deck immersed. The stability in these situations so far exceeds that in the draft range presented as to make comparison meaningless. However, Appendix II does present the calculations of the righting arms from which the GM may be ascertained in these regions. The conclusion to be drawn from FIG. 11 is that judicious choice of stability column angularity will produce a wide based semi-submersible vessel with improved GM over the entire operating range of drafts. From this initial study, an angle of from about 10 to about 20 is preferable. LARGE ANGLE STABILITY The curves of righting arm (GZ) versus heel angle were calculated for the straight-legged baseline vessel and the wide based semi-submersible vessel configurations with the stability columns angled 200 and 30 . The details of the calculations are presented in Appendix II hereof. The results are presented in FIGS. 12A-12F. To aid the comparison of the different configurations considered, each of FIGS. 12A-12F presents the results for the three vessels at a particular draft. The drafts used vary from 24.1 feet, pontoons almost immerging, to eighty-four feet, buoyant deck almost awash. Each of FIGS. 12A-12F shows the CZ along the vertical axis corresponding to the vessel's heel angle along the horizontal axis. In each case studied, the large angle stability increased with increasing stability column angularity. Additionally, one should note that the maximum righting arm and the area under the curve, righting energy, varied inversely with draft. All configurations possessed greater righting energy at shallower draft than when deeply ballasted. From this portion of the study, one must conclude that any angularity of the stability columns is beneficial, and that the more angular they are, the more benefit derived. Another important observation to be gleaned from this portion of the study concerns heeling due to wind. Egon P.D. Bjerregaard, and Svem Belschov, "Wind Overturning Effect on a Semi-Submersible'l, OTC paper 3063, lDth Annual Offshore Technology Conference, Houston, Texas, May 8-11, 1978, presents the wind heel moments and levers for the MSV "IOLAIR" as calculated by the ABS method. The information given was used to develop approximate wind heel curves for the configurations of this study. The resulting heeling arms are plotted on FIGS. 12A-12F. They reveal that the straight-legged baseline vessel will heel as much as 170 under a 51.44 m/s (100 knot) wind when at the design draft of 15.24m (50 feet). However, the wide based semi-submersible vessel configurations studied will heel less than 30 under the same circumstances. The great difference reveals the sensitivity of vessel performance to small differences in GM and configuration, and is attributable to the relationship between the angle of the righting arms and the heeling arms. DAMAGED STABILITY The study included a brief review of the damaged stability of the straight-legged baseline vessel and a wide based semi-submersible vessel with stability columns angled 300. Two conditions were studied. The first, a flooding of one forward stability column between the top of the pontoon and the bottom of the buoyant deck; the second, the same column combined with the first 23.lem (76 feet) of its pontoon. The cases were chosen to represent catastrophic casualties and ignored the greater degree of subdivision actually expected in the final design. The analysis reveals that for both extents of damage, the wide based semi-submersible vessel retains greater righting energy, and suffers less immersion than the baseline vessel. For the purpose of this study, the relative performance of the two configurations considered and not the absolute nunbers are important. Because the simplified hullform chosen had only a watertight ring around the main deck instead of a fully buoyant structure, the final measurement of heel and trim are exaggerated. The final design would have a fully buoyant deck structure. For the purposes of comparison therefore, the following table presents the results of the two conditions studied. The details of the damaged stability calculation are presented in Appendix III. DAMAGE STABILITY RESULTS Baseline WBSS 300 Vessel Compartment Column & Column & BR< Flooded Column Pontoon Column Pontoon Heel 18.00 21.00 12.20 17.00 Trim (m/ft) 10.36/34.0 15.54/51.0 11.89/39.0 13.87/45.5 Draft (m/ft) 17.62/57.8 19.81/65.0 18.41/60.4 20.42/67.0 Height of corner above final WL -0.043/-0.14 -5.82/-19.1 0.96/3.16 -3.96/-13.0 (m/ft) CONCLUSIONS The proposed concept of a wide based semi-submersible vessel d does s produce a vessel with superior characteristics in all areas of stability. For the vessel size and proportions chosen as a baseline, a preferred angle for the stability column lies between 100 and 200, but superior characteristics were shown for angles of the stability columns of greater than 0 to 300. The exact configuration depends on the desired operational characteristics. A buoyant deck structure is beneficial at large angles of heel and in damaged conditions, and is preferably incorporated in the design. Although the foregoing description and study were specific to a semi-submersible vessel having an elongated deck and parallel pontoons connected to the deck by stability columns such as shown in FIG. 13, the present invention contemplates any number of stability columns, and angling the stability columns outboard from the deck structure of any of the many semi-submersible vessel configurations such as shown in FIGS. 14-23. FIG. 14 shows a pentagon arrangement of stability columns 96 and footings 97. Each of FIGS. 13 and 14 also show a drilling rig 100, 101 and means for propelling the respective vessels 102, 103. The present invention contemplates angling the stability columns 96 and footings 97 radially outwardly to improve the stability of the pentagon vessel shown. Similarly, FIG. 15 shows a delta arrangement of stability columns 104 and footings 105 with such stability columns and footings angled radially outwardly as shown by the dashed lines. The semi-submersible vessel configurations of FIGS. 16-23 are known as FIG. 16 Ring, FIG. 17 A-Type, FIG. 18 Y-Type, FIG. 19 V-Type, FIG. 20 Catamaran, FIG. 21 Angle Catamaran, FIG. 22 Trimaran and FIG. 23 Grid. A semi-submersible vessel constructed in accordance with the present invention is particularly suitable for operation in ice-infested waters. For example with reference to FIG. 3, the vessel is shown on station drilling a subsea borehole with a drilling rig 53 through a conduit or moonpool 55 through the deck 10. When it is desirable to break an outboard ice-mass such as shown at 61, seawater ballast in ballast tanks 66 is pumped overboard by pumps 57, 59 to raise the vessel such that the columns 20 exert an upward bending force on the mass 61 to break it. Conversely, when it is desirable to break an ice mass below the deck 10 such as the mass shown at 63, ballast is pumped by means of pumps 57, 59 from the surrounding water to ballast tanks 56 to deep ballast or settle the vessel in the water such that the stability columns 20 exert a downward bending force on the mass 63 to break it. A semi-submersible vessel such as those contemplated by the present invention find use not only in drilling as shown with respect to FIG. 3, but also in producing at offshore sites, and for general utility services at offshore facilities such as a rescue vessel. Thus, it is contemplated that a semi-submersible vessel used for utility purposes may serve as an ice breaker to protect offshore facilities. APPZNDZX I EYDROSTATICS 1 BASELINE CONFIGURATION it WBSS 20o CONFIGURATION iii WBSS 30 CONFIGURATION HYDROSTATICS BASELINE O DEG DATE UNITS ANC DEFINITIONS DISPLACEMENT CISMLACEMENT(LONG TONS) DRAFT HEIGHT ABOVE BASELINE(FEET) AT AMIDSHIPS KB HEIGHT OF CENTER OF BUOYANCY(FEET) ABOVE BASELINE LCB LONG. CENTER OF BUOYANCY(FEET) FORM AMIDSHIES (+ FWD) LCF LONG. CENTER OF FLOTATION(FEET) FROM AMIDSHIPS (+ FWD) LING KM LONGITODINAL METACENTRIC HEICHT(FEET) AROVE BASELINE MTI HOMENT TO CHANGE TRIM ONE INCH(FOOT-TOUS,GML=BML) TPI TOUS PER INCH IMMERSION TRANS KM TRANSVERSE METACENTRIC HEIGMT(FEET) ABOVE BASELINE VOLUME DISPLACED VOLUME(CUBIC FEET) WPLANE AREA AREA OF THE WATERPLANE(SQUARE FEET) VESSEL LENGTH = 328.00 FEET MAXIMUM BEAM @168.00 FEET VESSEL OFFSET FILE NAME MSV-A1 VESSEL OFFSET FILE CREATED 10/22/82 TRIM 0.00 FEET WATER DENSITY 35.0 CUBIC FEET/TCN DRAFT VOLUME DISPLACEMENT LCB KB WPLANE AREA 20.000 472320 13494.85 0.000 10.000 23616,00 23.999 566760 16193.15 0.000 11.999 23616,00 24.001 566789 16193.97 0.000 12.000 5184.00 30.000 597888 17082.51 0.000 12.780 5184.00 40.000 649728 18563.65 0.000 14.553 5184.00 50.000 701568 20044.80 0.000 16.802 5184.00 60.000 753408 21525.94 0.000 19.431 5184.00 70.000 805248 23007.08 0.000 22.364 5184.00 83.999 877818 25080.53 0.000 26.881 5184.00 84.001 877847 25081.35 0.000 26.883 23520.00 DPAFT LCF TPI LONG KM TRANS kM MT1 20.000 0.000 56.2 529.4 233.20 1780.9 23.999 0.000 56.3 444.8 198.00 1780.9 24.001 0.000 12.3 144.9 52.28 546.9 30.000 0.000 12.3 138,8 50.96 546.9 40.000 0.000 12.3 130.5 49.69 546.9 50.000 0.000 12.3 124.2 49.34 546.9 60.000 0.000 12.3 119.4 49.73 546.9 70.000 0.000 12.3 115.9 50.71 546.9 83.999 0.000 12.3 112.7 52.88 546.9 84.001 0.000 56.0 404.8 114.47 2408.8 HYDROSTATICS 20 DEG DATE UNITS AND DEFINITIONS DISPLACEMENT DISPLACEMENT(LONG TONS) DRAFT HEIGHT AGOUE GASELINE(FEET) AT AMIDSHIPS KB HEIGHT OF CEMTER OF BUOYANCY(FEET) ABOVE BASELINE LCB LONG. CENTER OF BUOYANCY(FEET) FROM AMIDSHIPS (+ FWD) LCF LOGN. CENTER OF FLOTATION(FEET) FROM AMIDSHIPS (+ FWD) LONG KM LONGITUDINAL METACENTRIC HEIGHT(FEET) ABOVE BASELINE MTI MOMENT TO CHANGE TRIM ONE INCH(FOOT-TONS,GML=DML) MPI TONS PER INCH IMMERSION TRANS KM TRANSVERSE METACENTRIC HEIGHT(FEET) ABOVE BASELINE VOLUME DISPLACED VOLUME(CUBIC FEET) WPLANE AREA AREA OF THE WATERPLANE(SQUARE FEET) VESSEL LENGTH 1 329.00 FEET MAXIMUM BEAM =212.00 FEET VESSEL OFFSET FILE NAME MSV-A7 VESSEL OFFSET FILE CREATED TRIM 0.00 FEET WATER DENSITY 35.0 CUBIC FEET/TON DRAFT VOLUME DISPLACEMENT LCB KB WPLANE AREA 20.000 472320 13494.85 0.000 10.000 23616.00 23.999 566760 16193.15 0.000 11.999 23616.00 24.001 566789 16193.98 0.000 12.000 5521.60 30.000 599913 17140.38 0.000 12.829 5521.60 40.000 655129 18717.89 -0.000 14.697 5521.60 50.000 710345 20295.59 0.000 17.052 5521.60 60.000 765561 21873.19 0.000 19.789 5521.60 70.000 820777 23450.79 0.000 22.830 5521.60 83.999 898074 25659.28 0.000 27.493 5521.60 84.001 898104 25660.13 0.000 27.495 24320.25 DARFT LCF TRI LONG KM TRANG KM MTI 20.000 0.000 56.2 529.4 402.60 1780.9 23.999 0.000 56.2 444.8 339.17 1780.9 24.001 0.000 13.1 153.5 86.63 582.5 30.000 0.000 13.1 146.6 79.85 582.5 40.000 0.000 13.1 137.1 70.93 582.5 50.000 0.000 13.1 130.0 64.38 582.5 60.000 0.000 13.1 124,6 59.69 582.5 70.000 0.000 13.1 120.6 59.69 582.5 83.999 0.000 13.1 116.8 53.97 582.5 84.001 0.000 57.9 403.4 115.63 2450.7 HYDROSTATICS 30 DEG DATE UNITS AND DEFINITIONS DISPLACEMENT DISPLACEMENT(LUNG @UNS) DRAFT HEIGHT ABOVE BASELING(FEET) AT AMIDSHIPS KB HEIGHT OF CENTER OF BUOVANCY(FEET) ABOVE BASELINE LCB LONG. CENTER OF BUOYANCY(FEET) FROM AMIDSHIPS (+ FWD) LCF LONG. CENTER OF FLOTATION(FEET) FROM ANIDSHIPS (+ FWD) LONG KM LONGITUDINAL METACENTRIC HEIGHT(FEET) ABOVE BASELINE MT1 MOMENT TO CHANGE TRIM ONE INCH(FOOT-TONS,GML-BML) TPI TONS PER INCH IMMERSION TRANS KM TRANSVERSE METACENTRIC HEIGHT(FEET) ABOVE BASELINE VOLUME DISPLACED VOLUME(CUBIC FEET) WPLANE AREA AREA OF THE WATERPLANE(SQUARE FEET) VESSEL LENGTH r 328.00 FEET MAXIMUM BEAM =237.26 FEET VESSEL OFFSET FILE NAME MSV-A5 vESSEL OFFSET FILE CREATED 10/15/82 TRIM 0.00 FEET WATER DENSITY 35.0 CUBIC FEET/TON DRAFT VOLUME DISPLACEMENT LCB KB WPLANE AREA 20.000 - 472320 13494.85 0.000 10.000 23616.00 23.999 566760 16193.15 0.000 11.999 23616.00 24.001 566789 16193.99 0.000 12.000 5985.36 30.000 602696 17219.89 0.000 12.893 5985,36 40.000 662549 18929.99 0.000 14.890 5985.36 50.000 722403 20640.09 0.000 17.383 5985.36 60.000 782256 22350.19 0.000 20.263 5985.36 70.000 842110 24060.30 0.000 23.443 5985.35 83.999 925899 26454.27 0.000 26.289 5985.36 8@.001 925931 26455.17 0.000 28.291 25419.52 DRAFT LCF TPI LONG KM TRANS KM MT1 20.000 0.000 56.2 529.4 521.82 1780.9 23.999 0.000 56.2 444.8 438.53 1780.9 24.001 0.000 14.2 165.4 115.72 631.4 30.000 0.000 14.2 157.2 103.76 631.4 40.000 0.000 14.2 146.1 87.90 631.4 50.000 0.000 14.2 137.8 76.06 631.4 60.000 0.000 14.2 131.4 67.30 631.4 70.000 0.000 14.2 126.7 60.97 631.4 83.999 0.000 14.2 122.2 55.3 431.4 84.001 0.000 60.5 401.4 116.91 2508.4 APPENDIX IS RIGHTING ARM CURVES i BASELINE CONFIGURATION ii WASS 20 CONFIGURATION iii WBSS 30 CONFIGURATION iv VCG BASELINE CONFIGURATION 9 VCG 200 CONFIGURATION vi VCG 300 CONFIGURATION i BASELINE CONFIGURATION DYNAMIC STABILITY VESSEL NAhE VASELINE DATE 11/9/82 UNITS AND DEFINITIONS DISPLACEMENT DISPLACEMENT(LONG TONS) DRAFT HEIGHT ABOVE BASELINE AT CENTERLINE AMIDSHIPS(FEET) KG HEIGHT OF CENTER OF GRAVITY ABOVE BASELINE(FEET) LCB LONG.CENTER OF BUOYANCY(FEET) FRON AMIDSHIPS(+=FWD) LCG LONG.POSITION OF CENTER OF GRAVITY(FEET) FROM AMIDSHIPS(+=FWD) TRIM TRIM(FEET)(+= AFT) RA RIGHTING ARM(FEET) OFFSET FILE NAME MSV-A1 DATE CREATED 10/22/82 VESSEL LENGTH r 328.00 FEET WATER DENSITY s 35.00 CUBIC FEET/TON DESIGN CONDITION 1 DRAFT 23.000 DISPLACEMENT 15,500.00 KG 54.580 LCG 0.000 HEEL ANGLE RA DISPLACEMENT LCB DRAFT TRIM ITERATIONS 0.00 0.0000 15,500.00 -0.000 22.971 0.000 2 0.5 1.5123 15,499.99 0.000 22.971 0.000 1 5.00 4.3=71 15,499.99 -0.000 26.009 0.000 2 10.00 6.8747 15,499.99 0.000 29.761 0.000 15.00 9.6708 15,500.00 0.000 33.631 0.000 20.00 12.8780 15,500.00 0.000 37.687 0.000 2 25.00 16.7029 15,500.00 0.000 42.010 0.000 3 30.00 23.5259 15,500.00 0.000 45.929 0.000 4 35.00 35.3163 15,500.00 0.000 46.228 0.000 40.00 40.3638 15,500.00 -0.000 43.347 0.000 3 DCSIGN CONDITION 2 DRAFT 23.900 DISPLACEMENT 16,000.00 KG 53.250 LCG 0.000 PEEL ANGLE RA DISPLACEMENT LCB DRAFT TRIM ITERATIONS 0.00 0.0000 16,000.00 0.000 23.712 0.000 2 0.57 0.7840 16,00.00 -0.000 23.951 0.000 2 5.00 2.9066 16,00.00 0.000 27.224 0.000 2 10.00 5.4191 15,999.99 -0.000 30.976 0.000 2 15.00 8.1817 15,999.99 0.000 34.847 0.000 2 20.00 11.3517 15,999.99 -0.000 38.902 0.000 2 25.00 15.1286 15,999.99 0.000 43,225 0.000 3 30.00 22.6365 16,000.00 -0.000 47.015 0.000 4 35.00 35.1556 16,000.00 0.000 47.529 0.000 3. 40.00 40.8842 16,000.00 0.000 46.190 0.000 3 DESIGN CONDITION 3 DRAFT 24.100 DISPLACEMENT 16,200.00 KG 52.740 LCG 0.000 HEEL ANGLE RA DISPLACEMENT LCB DRAFT TRIM ITERATIONS 0.00 0.0000 16,200.00 0.000 24.041 0.000 2 0.57 0.2544 16,200.00 0.000 24.437 0.000 2 5.00 2.3639 16,200.00 0.000 27.710 0.000 2 10.00 4.8640 16,199.99 -0.000 31.463 0.000 2 15.00 7.6148 16,200.00 0.000 35.333 0.000 2 20.00 10.7715 16,200.00 0.000 39.389 0.000 2 25.00 14.5310 16,199.99 0.000 43.711 0.000 2 30.00 22.2991 16,200.00 0.000 47.431 0.000 4 35.00 35.0381 16,200.00 0.000 48.045 0.000 3 40.00 40.8731 16,200.00 0.000 47.297 0.000 3 DESING CONDITION 4 DR-FT 30.000 DISPLACEMENT 17,000.00 KG SO. 820 LCG 0.000 HEEL ANGLE RA DISPLACEMENT LCB DRAFT TRIM ITERATIONS 0.00 0.0000 17,000.00 -0.000 29.442 0.000 2 0.57 0.0025 17,000.00 -0.000 29.442 0.000 1 5.00 0.4291 16,999.99 -0.000 30.011 0.000 4 10.00 2.7966 16,999.99 -0.000 33.473 0.000 4 15.00 5.4965 16,999.99 0.000 37.285 0.000 3 20.00 8.6067 16,999.99 0.000 41.333 0.000 2 25.00 12.3051 17,000.00 0.000 45.656 0.000 2 30.00 21.0474 17,000.00 0.000 49.011 0.000 4 35.00 34.2961 17,000.00 -0.000 50.091 0.000 3 40.00 39.8018 17,000.00 -0.000 51.568 0.000 3 DESIGN CONDITION 5 DRAFT 37.000 DISPLACEMENT 18,000.00 KG 48.670 LCG 0.000 HEEL ANGLE RA DISPLACEMENT LCB DRAFT TRIM ITERATIONS 0.00 0.0000 18,000.00 -0.000 36.194 0.000 2 0.57 0.0138 18,000.00 0.000 36.194 0.000 1 5.00 0.1327 17,999.99 -0.000 36.194 0.000 1 10.00 0.7730 17,999.99 -0.000 36.841 0.000 4 15.00 3.2345 17,999.99 0.000 40.121 0.000 4 20.00 6.2431 17,999.99 0.000 43.956 0.000 4 25.00 9.8762 17,999.99 0.000 48.159 0.000 4 30.00 19.8191 18,000.00 0.000 50.894 0.000 4 35.00 32.8419 18,000.00 0.000 52.606 0.000 3 40.00 36,7829 18,000.00 0.000 56.529 0.000 4 DESIGN CONDITION 6 DRAFT 44.000 DISPLACEMENT 19,000.00 KG 46.740 LCG 0.000 HEEL ANGLE RA DISPLACEMENT LCB DRAFT TRIM ITERATIONS 0.00 0.0000 19,000.00 0.000 42.945 0.000 2 0.57 0.0276 19,000.00 0.000 42.945 0.000 1 5.00 0.2522 18,999.99 0.000 4.945 0.000 1 10.00 0.5724 19,000.00 -0.000 42.945 0.000 1 15.00 1.5740 18,999.99 -0.000 ' 43.777 0.000 4 20.00 4.3235 18,999.99 -0.000 47.049 0.000 4 25,00 8.2735 19,000.00 0.000 50.808 0.000 3 30.00 18.9554 18,999.99 0.000 52.723 0.000 3 35.00 30.9297 19,000.00 0.000 55.075 0.000 3 40.00 33.4672 19,000.00 -0.000 60.633 0.000 4 DESIGN CONDITION 7 <RTI ID=24.1> DRAFT 50.000 DISPLACEMENT 20,000.00 KG 45.000 LCG 0.000 HEEL ANGLE RA DISPLACEHENT LCB DRAFT TRIM ITERATIONS 0.00 0.0000 20,000.00 0.000 49.697 0.000 2 0.57 0.0434 20,000.00 0.000 49.697 0.000 1 5.00 0.3894 19,999.99 -0.000 49.697 0.000 1 10.00 0.8423 20,000.00 0.000 49.697 0.000 1 15.00 1.4272 20,000.00 0.000 49.697 0.000 1 20.00 2.9469 19,999.99 0.000 50.840 0.000 4 25.00 7.5675 20,000.00 -0.000 53.467 0.000 2 30.00 18,4348 19,999.99 0.000 54.597 0.000 3 35.00 28.6557 20,000.00 -0.000 57.502 0.000 3 40.00 30.2853 20,000.00 -0.000 64.128 0.000 4 DESIGN CONDITION 9 DRAFT 70.000 DISPLACEMENT 23,000.00 KG 40.700 LCG 0.000 HEEL ANGLE RA DISPLACEMENT LCB DRAFT TRIM ITERATIONS 0.00 0.0000 22,999.99 0.000 69.952 0.000 2 0.57 0.1001 23,000.00 0.000 69.952 0.000 1 5.00 0.8819 23,000.00 0.000 69.952 0.000 1 10.00 1.8149 23,000.00 0.000 69.952 0.000 1 15.00 3,7678 23,000.00 0.000 68.028 0.000 4 20.00 6.4031 22,999.99 0.000 64.916 0.000 4 25.00 9.6097 22,999.99 0.000 61.545 0.000 4 30.00 17.1366 22,999.99 0.000 66,335 0.000 3 35.00 20.8969 22,999.99 0.000 66.217 0.000 4 40.00 21.7217 22,999.99 0.000 73.984 0.000 4 DESIGN CONDITION 9 DRAFT 83.900 DISPLACEMENT 25,000.00 KG 38.400 LCG 0.000 HEEL ANGLE RA DISPLACEMENT LCB DRAFT TRIM ITERATIONS 0.00 0.0000 25,000.00 0.000 83.455 0.000 0.5' 0.170e 25,000.00 0.000 83.392 0.000 3 5.00 2.3355 25,000.00 0.000 80.732 0.000 4 10.00 4.8455 25,000.00 0.000 77.660 0.000 4 15.00 7.4870 25,000.00 0.000 74.490 0.000 4 20.00 10.3425 25,000.00 0.000 71.168 0.000 4 25.00 13.1418 24,999.99 0.000 68.265 0.000 4 30.00 15.5236 24,999.99 0.000 68.411 0.000 3 35.00 15.7176 24,999.99 0.000 74.113 0.000 4 40.00 17.2840 24,999.99 0.000 81.793 0.000 4 DESIGN CONDITION 10 DRAFT 84.100 DISPLACEMENT 25,200.00 KG 38.190 LCG 0.000 HEEL ANGLE RA DISPLACEMENT LCB DRAFT TRIM ITERATICNS 0.00 0.0000 25,200.00 0.000 84.177 0.000 2 0.5 0.4420 25,200.00 0.000 83.974 0.000 3 5.00 2.6403 25,200.00 0.000 81.320 0.000 4 10.00 5.1769 25,200.00 0.000 78.249 0.000 4 15.00 7.8409 25,200.00 0.000 75.080 0.000 4 20.00 10.7137 25,199.99 0.000 71.759 0.000 4 25.00 13.3906 25,199.99 0.000 69.095 0.000 4 30.00 15.2796 25,199.99 0.000 69.470 0.000 3 35.00 16.3713 25,199.99 0.000 75.055 0.000 4 40.00 16.9045 25,199.99 0.000 82.688 0.000 4 ii WBSS 20 CONFIGURATION DYNAMIC STABILITY VESSEL NAME 200EG WIDE DATE 11/10/82 UNITS AND DEFiNITIONS DISPLACEMENT DISPLACEMENT 'LONG TONS) DRAFT HEIGHT ABOVE VASELINE AT CENTERLINE AMIDSHIPS(FEET) KG HEIGHT OF CENTER OF GRAVITY ABOVE BASELINE FEET) LCB LONG.CENTEP OF BUOYANCY(FEET) FROM AMIDSHIPS(+-FwD) LCC LONG. POSITION OF CENTER OF GRAVITY(FEET) FROM AMIDSHIPS(+=FWD@ TRIM TRIM(FEET) (+= AFT) RA RIGHTING ARM(FEET) OFFSET FILE NAME MSV-47 DATE CREATED VESSEL LENGTH 328.00 FEET WATER DENSITY t 35.00 CUBIC FEET/TON DESIGN CONDITION 1 DRAFT 23.000 DISPLACEMENT 15,000.00 KG 55.110 LCG 0.000 HEEL ANGLE RA DISPLACEMENT LCB DRAFT TRIM ITERATIONS- 0.00 0.000 14,999.99 0.000 22.230 0.000 5 0.57 3.092 15,000.00 0.000 22.230 0.000 r 5.00 11.891 15,000.00 0.000 25.982 0.000 2 10.00 18.75? 14,999.99 -0.000 31.052 0.000 2 15.00 25.179 14,999.99 0.000 36.421 0.000 20.00 31.351 14,999.99 -0.000 42.190 0.000 3 25.00 37.492 15,000.00 0.000 48.450 0.000 5 3C.00 50.626 15,000.00 0.000 51.266 0.000 4 35.00 56.157 14,999.99 0.000 47.519 0.000 3 40.00 50.624 14,999.99 0.000 38.708 0.000 4 DESING CONDITION DRAFT 23.900 DISPLACEMENT 16,000.00 KG 53.760 LCG 0.000 HEEL ANGLE RA DISPLACEMENT LCB DRAFT TRIM ITERATIONS 0.00 0.000 16,000.00 -0.009 23.712 0.000 2 0.57 1.493 15,999,99 -0.000 24.082 0.000 2 5.00 7.578 16,000.00 -0.000 28.399 0.000 2 10.00 13.897 16,000.00 -0.000 33.482 0.000 15.00 19.828 16,000.00 -0.000 38.865 0.000 20.00 25.555 15,999.99 0.000 44.647 0.000 2 25.00 31.944 16,000.00 0.000 50.780 0.000 4 30.00 47.899 16,000.00 -0.000 53.647 0.000 4 35.00 57.120 16,000.00 0.000 52.471 0.000 3 40.00 52.746 15,999.99 0.000 44.869 0.000 5 DESIGN CONDITION 3 DRAFT 24.100 DISPLACEMENT 16,200.00 KG 53.250 LCG 0.000 HEEL ANGLE RA DISPLACEMENT LCB DRAFT TRIM ITERATIONS 0.00 0.000 16,199.99 -0.000 24.039 0.000 2 0.5@ 0.@@@ 16,200.00 0.000 24.5@3 0.000 2 5.00 6.803 16,199.99 -0.000 28.882 0.000 2 10.00 13.044 16,200.00 0.000 33.968 0.000 2 15.00 18.908 16,200.00 -0.000 39.353 0.000 2 20.00 24.576 16,200.00 -0.000 45.138 0.000 2 25.00 31.101 16,200.00 -0.000 41.221 0.000 4 30.00 47.495 16,200.00 -0.000 54.083 0.000 4 35.00 57.081 16,200.00 -0.000 53.434 0.000 3 40.00 53.286 16,199.99 -0.000 46.414 0.000 5 DESIGN CONDITION 4 DRAFT 30.000 DISPLACEMENT 17,100.00 KG 51.080 LCG 0.000 HEEL ANGLE RA DISPLACEMENT LCB DRAFT TRIM ITERATIONS 0.00 0.000 17,100.00 0.000 29.743 0.000 2 0.57 0.290 17.099.99 0.000 29.747 0.000 2 5.00 3.592 17.099.99 -0.000 31.182 0.000 4 10.00 9.464 17,100.00 0.000 36.155 0.000 2 15.00 15.054 17,100.00 -0.000 41.553 0.000 2 20.00 20.481 17,100.00 0.000 47.350 0.000 2 25.00 27.834 17,100.00 0.000 53.134 0.000 4 30.00 45.607 17,100.00 0.000 55.970 0.000 4 35.00 55.582 17,100.00 0.000 57.617 0.000 3 40.00 55.307 17,100.00 0.000 59.126 0.000 3 DESIGN CONDITION 5 DRAFT 37.000 DISPLACEMENT 18,150.00 KG 48.820 LCG 0.000 HEEL ANGLE RA DISPLACEMENT LCB DRAFT TRI ITERATIONS 0.00 0.000 18,150.00 0.000 36.399 0.000 0.57 0.250 18,150.00 -0.000 36.402 0.000 2 5.00 2.200 18,149.99 -0.000 36.631 0.000 2 10.00 5.904 18,149.99 0.000 39.113 0.000 4 15.00 11.093 18,149.99 -0.000 44.208 0.000 4 20.00 16.257 18,149.99 0.000 49.937 0.000 3 25.00 24.8@4 18,150.00 -0.000 55.236 0.000 4 30.00 43.018 18,150.00 -0.000 58,123 0.000 3 35.00 51.704 19,150.00 0.000 62.220 0.000 4 40.00 51.614 18,150.00 0.000 69.481 0.000 5 DESIGN CONDITION 6 DRAFT 44.000 DISPLACEMENT 19,200.00 KG 46,800 LCG 0.000 HEEL ANGLE RA DISPLACEMENt LCB DRAFT TRIM ITERATIONS 0.00 0.000 19,200.00 0.000 43.055 0.000 0.57 0.219 19,200.00 0.000 43.058 0.000 : : 5.00 1.927 19,200.00 0.000 43.280 0.000 10.00 3.949 19,199.99 0.000 43,969 0.000 2 15.00 7.802 19,199.99 0.000 47.428 0.000 4 20.00 12.619 19,199.99 0.000 52.829 0.000 4 25.00 22.646 19;199.99 -0.000 57.227 0.000 4 30.00 40.070 19,200.00 0.000 60.243 0.000 3 35.00 46.662 19,200.00 0.000 66.371 0.000 4 40.00 46.837 19,200.00 0.000 75.005 0.000 5 DESIGN CONDITION 7 DRAFT 50.000 DISPLACEMENT 20,250.00 KG 45.000 LCG 0.000 HEEL ANGLE RA DISPLACEMENT LCB DRAFT TRIM ITERATIONS 0.00 0.000 20,250.00 0.000 49.710 0.000 2 0.57 0.195 20,250.00 -0.000 49.713 0.000 2 5.00 1.719 20,250.00 0.000 49.929 0.000 2 10.00 3.523 20,250.00 0.000 50.597 0.000 2 15.00 5.532 20,249.99 0.000 51.798 0.000 4 20.00 9.605 20,250.00 0.000 56.198 0.000 4 25.00 21.087 20,250.00 0.000 59.221 0.000 3 30.00 36.873 20,249.99 -0.000 62.353 0.000 3 35.00 41.772 20,250.00 0.000 69.842 0.000 4 40.00 42.165 20,250.00 0.000 79.293 0.000 5 DESIGN CONDITION 8 DRAFT 70.000 DISPLACEMENt 23,450.00 KG 40.500 LOG 0.000 HEEL ANGLE RA DISPLACEMENT LCB DRAFT TRIM ITERATIONS 0.00 -0.000 23,450.00 0.000 69.994 0.000 2 0.57 0.159 23,450.00 0.000 69.997 0.000 2 5.00 1.405 23.450.00 0.000 70.192 0.000 2 10.00 2.887 23,450.00 0.000 70.765 0.000 4 15.00 6.081 23,450.00 0.000 69.089 0.000 4 20.00 10.468 23,450.00 0.000 66.626 0.000 3 25.00 18,890 23,449.99 0.000 65.669 0.000 4 30.00 26.851 23,449.99 0.000 70.193 0.000 4 35.00 23.779 23,449.99 0.000 79.073 0.000 4 40.00 29.533 23,449.99 0.000 89.839 0.000 4 DESIGN CONDITION 9 DRAFT 83.900 DISPLACEMENT 25,600.00 KG 38.100 LCG 0.000 HEEL ANGLE RA DISFLACEMENT LCB DRAFT TRIM ITERATIONS 0.00 0.000 25,600.00 0.000 83.623 0.000 2 0.57 0.219 25,600.00 0.000 83.485 0.000 3 5.00 2.647 25,600.00 0.000 80.922 0.000 4 10.00 5,733 25,600.00 0.000 78.103 0.000 4 15.00 9.318 25,599.99 0.000 75.349 0.000 4 20.00 13,574 25,599.99 0.000 72.683 0.000 4 25.00 17.709 25,599.99 0.000 71.795 0.000 4 30.00 20.609 25,599.99 0.000 77.685 0.000 4 35.00 22.059 25,599.99 0.000 86.399 0.000 4 40.00 22.711 25,599.99 0.000 97.157 0.000 4 DESIGN CONDITION 10 DRAFT 84.100 DISPLACEMENT 26,00.00 KG 37.700 LCG 0.000 HEEL ANGLE RA DISPLACEMENT LCB DRAFT TRIM ITERATIONS 0.00 0.000 26,000.00 0.000 84.490 0.000 2 0.57 0.685 26,000.t00 0.000 84.440 0.000 3 5.00 3.201 26,000.00 0.000 82.005 0.000 4 10.00 6.307 26,000.00 0.000 79.186 0.000 4 15.00 9.894 26,000.00 0.000 76.422 0.000 4 20.00 14.031 25,999.99 0.000 73.878 0.000 4 25.00 17.520 25,999.99 0.000 73.566 0.000 3 30.00 19.642 25,999.99 0.000 79.325 0.000 4 35.00 20.983 25,999.99 0.000 87.934 0.000 4 40.00 21.612 25,999.99 0.000 98.650 0.000 4 iii WBSS 30 CONFIGURATION DYNAMIC STABILITY VESSEL NAME 30DEG+39.20B WID DATE 11/10/82 UNITS AND DEFINITIONS DISPLACEMENT DISPLACEHENT(LONG TONS) DRAFT HEIGHT ABOVE BASELINE AT CENTERLINE AMIDSHIPS(FEET) KG HEIGHT OF CENTER OF GRAVITY ABOVE BASELINE(FEET) LCB LONG.CENTER OF BUOYANCY(FEET) FROM AMIDSHIPS(+=FWD) LCG LONG.POSITION OF CENTER OF CRAVITY(FEET) FROM AMIDSHI@S(+=FWD) TRIM TRIM(FEET)(+=FEET) RA RICHTING ARM(FEET) OFFSET FILE NAME MSV-AS DATE CREATED 10/15/82 VESSEL LENGTH = 328.00 FEET WATER DENSITY = 35.00 CUBIC FEET/TON DESIGN CONDITION 1 DRAFT 22.000 DISPLACEMENT 15,500.00 KG 55.860 LCG 0.000 HEEL ANGLE RA DISPLACEHENT LCB DRAFT TRIM ITERATIONS 0.00 0.000 15,499.99 -0.000 22.971 0.000 2 0.57 3,920 15,499.99 0.000 22.990 0.000 3 5.00 13,624 15,500.00 0.000 27,756 0.000 2 10.00 23.140 15,500.00 0.000 33.497 0.000 2 15.00 31.602 15,499.99 0.000 39.662 0.000 2 20.00 39.292 15,500.00 -0.000 46.360 0.000 3 25.00 48.591 15,500.00 0.000 53.066 0.000 5 30.00 64.239 15,500.00 0.000 54,337 0.000 4 35.00 62.815 15,499.99 0.000 48.001 0.000 4 40.00 56.858 15,499.99 0.000 39.311 0.000 4 DESIGN CONDITION DRAFT 23.900 DISPLACEMENT 16,000.00 Kt 54.490 LCG 0.000 HEEL ANGLE RA DISPLACEMENT LCB DRAFT TRIM ITERATIONS 0.00 0.000 16,000.00 0.000 23.712 0.000 2 0.57 2.018 16,000.00 0.000 24.146 0.000 2 5.00 11.258 15,999.99 0.000 28.950 0.000 2 10.00 20.441 15,999.99 -0.000 34.702 0.000 2 15.00 28.624 16,000.00 0.000 40.877 0.000 2 20.00 36.077 15,999.99 0.000 47.585 0.000 3 25.00 46.182 16,000.00 0.000 54.154 0.000 5 30.00 63.466 15.999.99 -0.000 55.674 0.000 4 35.00 68.861 15.999.99 0.000 50.395 0.000 4 40.00 58.146 16,000.00 0.000 42.068 0.000 5 DESIGN CONDITION 3 DRAFT 24.100 DISPLACEMENT 16,200.00 KG 53.960 LCG 0.000 HEEL ANGLE RA DISPLACEMENT LCB DRAFT TRIM ITERATIONS 0.00 -0.000 16,200.00 0.000 24.036 0.000 0.57 1.246 16,199.99 0.000 24.619 0.000 5.00 10.353 16.200.00 0.000 29.428 0.000 10.00 19.410 16,199.99 0.000 35.184 0.000 2 15.00 27.487 16,199.99 0.000 41.363 0.000 2 20.00 34.852 16,200.00 0.000 48.075 0.000 3 25.00 45.268 16,200.00 0.000 54.566 0.000 5 30.00 63.092 16,200.00 0.000 56.199 0.000 3 35.00 64.253 16,199.99 0.000 51.437 0.000 4 40.00 58.629 16,199.99 0.000 43.236 0.000 5 DESIGN CONDITION 4 DRAFT 30.000 DISPLACEMENT 17,300.00 KG 51.290 LCG 0.000 HEEL ANGLE RA DISPLACEMENT LCB DRAFT TRIM ITERATIDNS 0.00 -0.000 17,299.99 0.000 30.468 0.000 2 0.57 0.516 17,299.99 -0.000 30.473 0.000 2 5.00 5.789 17,299.99 0.000 32.138 0.000 4 10.00 14.168 17,299.99 0.000 37.835 0.000 2 15.00 21.715 17,299.99 -0.000 44.037 0.000 2 20.00 28.634 17,299.99 0.000 50.771 0.000 2 25.00 40.732 17,300.00 -0.000 56.67 0.000 30.00 60.376 17,300.00 0.000 59.042 0.000 3 35.00 66.013 17.300.00 0.000 58.837 0.000 3 40.00 60.954 17,299.99 0.000 51.761 0.000 5 DESIGN CONDITION S DRAFT 37.000 DISPLACEMENT 18,400.00 KG 48.950 LCG 0.000 HEEL ANGLE RA DISPLACEMENT LCB DRAFT TRIM ITERATIONS 0.00 -0.000 18,400.00 0.000 36.900 0.000 2 0.57 0.433 18,400.00 -0.000 36.906 0.000 2 5.00 3.808 18,399.99 0.000 37.304 0.000 10.00 9.662 18,399.99 -0.000 40.707 0.000 4 15.00 16.662 18,399.99 -0.000 46.725 0.000 3 20.00 23.197 18,400.00 0.000 53,467 0.000 25.00 37.117 18,400.00 0.000 58.662 0.000 4 30.00 56.769 18,400.00 0.000 61.814 0.000 3 35.00 62.407 18,400.00 0.000 66.877 0.000 4 40.00 61.386 18,400.00 0.000 73.403 0.000 5 DESIGN CONDITION 6 DRAFT 44.000 DISPLACEMENT 19,500.00 KG 46.860 LCG 0.000 HEEL ANGLE RA DISPLACEMENT LCB DRAFT TRIM ITERATIONS 0.00 -0.000 19,500.00 0.000 43.333 0.000 0.57 0.367 19,499.99 0.000 43.338 0.000 2 5.00 3.222 19,499.99 0.000 43.720 0.000 2 10.00 6.559 19,499.99 0.000 44.906 0.000 4 15.00 12.360 19,499.99 -0.000 49.799 0.000 4 20.00 18.488 19,500.00 0.000 56.281 0.000 4 25.00 34.237 19,500.00 0.000 60.549 0.000 4 30.00 52.513 19,500.00 0.000 64.519 0.000 3 35.00 56.438 19,500.00 0.000 72.276 0.000 5 40.00 56.157 19,500.00 0.000 81.778 c.000 5 <RTI ID=36.1> DESIGN CONDITION 7 DRAFT 50.000 DISPLACEMENT 20,600.00 KG 45.000 LCG 0.000 HEEL ANGLE RA DISPLACEMENT LCB DRAFT TRIM ITERATIONS 0.00 0.000 20.600.00 0.000 49.765 0.000 2 0.57 0.313 20.600.00 -0.000 49.770 0.000 2 5.00 2.748 20.600.00 0.000 50.136 0.000 2 10.00 5.596 20.599.99 0.000 51.271 0.000 2 15.00 9.001 20.599.99 0.000 53.678 0.000 4 20.00 15.259 20.600.00 0.000 59.146 0.000 4 25.00 31.848 20.599.99 0.000 62.379 0.000 4 30.00 47.767 20.600.00 0.000 67.162 0.000 4 35.00 50.548 20,600.00 0.000 76.389 0.000 5 40.00 50.580 20,600.00 0.000 87.075 0.000 5 DESIGN CONDITION 8 DRAFT 70.00C DISPLACEMENT 24,000.00 KG 40.330 LCG 0.000 HEEL ANGLE RA DISPLACEMENT LCE DRAFT TRIM ITERATIONS 0.00 0.000 24,000.00 0.000 69.647 0.000 2 0.57 0.208 24,000.00 0.000 69.651 0.000 2 5.00 1.828 23,999.99 0.000 69.967 0.000 2 10.00 3.752 24,000.00 0.000 70.901 0.000 4 15.00 7.859 24,000.00 0.000 69.618 0.000 4 20.00 13.762 24,000.00 0.000 67.689 0.000 3 25.00 25.944 24,000.00 0.000 68.721 0.000 4 30.00 32.592 23,999.99 0.000 75.860 0.000 4 35.00 34.506 23,999.99 0.000 86.275 0.000 4 40.00 35.177 23,999.99 0.000 98.716 0.000 5 DESIGN CONDITION 9 DRAFT 83.900 DISPLACEMENT 26,200.00 KG 37.950 LCG 0.000 HEEL ANGLE RA DISPLACEMENT LCB DRAFT TRIM ITERATIONS 0.00 0.000 26,199.99 0.000 82.@12 0.000 2 0.57 0.178 26,199.99 0.000 82.@1@ 1.000 2 5.00 2.657 26,200.00 0.000 80.@21 0.000 4 10.00 0.202 26,200.00 0.000 77.913 0.000 4 15.00 10.55@ 26,199.99 0.000 75.4@2 0.000 4 20.00 16.000 26,199.99 0.000 73.35@ 0.000 4 25.00 21.673 26,199.99 0.000 74.601 0.000 4 30.00 24.812 26,199.99 0.000 81.701 0.000 4 35.00 26.374 26,199.99 0.000 93.02@ 0.000 4 40.00 27.062 26,199.99 0.000 105.44@ 0.000 4 DESIGN CONDITION 10 DRAFT @4.100 DISPLACEMENT 26,700.00 KG 37.400 LCG 0.000 HEEL ANGLE RA DISPIACEMENT LCB DRAFT TRIM ITERATIONS 0.00 -0.000 26,700.00 0.000 84.338 0.000 2 0.57 0.603 26,700.00 0.000 84.228 0.000 3 5.00 3.296 26,700.00 0.000 8@.815 0.000 4 10.00 6.819 26,700.00 0.000 79.18@ 0.000 4 15.00 11.160 26,700.00 0.000 76.72@ 0.000 3 20.00 16.337 26,699.99 0.000 74.77@ 0.000 4 25.00 20.789 26,699.99 0.000 76.44@ 0.000 4 30.00 23.298 26,699.99 0.000 84.44@ 0.000 4 35.00 24.774 26,699.99 0.000 84.688 0.000 4 40.00 26.468 26,699.99 0.000 10@.0@1 0.000 4 iv VCG BASELINE CONFIGURATION VCG = 45' @ 20,000 LT DESIGN DISPLACEMENT DISP. dBALLAST dBALL MOM TOTAL MOM KG LT LT ft-LT ft-LT ft 25000 5000 60000 960000 38.40 23000 3000 36000 936000 40.70 20000 0 0 900000 45.00 19000 -1000 -12000 888000 46.76 18000 -2000 -24o00 876000 48.67 17000 -3000 -36000 864000 50.82 16200 -3800 -45000 854400 52.74 16400 -4000 -48: :Q0 852000 53.25 15500 -45000 -54000 846000 54.58 v VCG 20 CONFIGURATION VCG a 45' @ 20,250 LT DESIGN DISPLACEMENT DISP. dBALLAST dBALL MOM TOTAL MOM KG LT LT ft-LT ft-LT ft 26000 5750 69000 980250 37.70 25600 5350 64200 975450 38.10 23430 3200 38400 949650 40.50 20250 0 0 911250 45.00 19200 -1050 -12600 898650 46.80 18130 -2100 -2520O 886050 48.82 17100 -3130 -37800 873450 S1.08 16200 -40 0 -48600 862650 53.25 16000 -4250 -51000 860250 53.76 15500 -4750 -57000 854250 55.11 @ vi VCG 30 CONFIGURATION VCG = 45' @ 20,000 LT DESIGN DISPLACEMENT DISP. dBALLAST dBALL MOM TOTAL MOM KG LT LT ft-LT ft-LT ft 26700 6100 73200 1000200 37.46 26200 5600 67200 994200 37.95 24000 3400 40800 967800 40.33 20600 0 0 927000 45.00 19500 -1100 -13200 913800 46.86 18400 -2200 -2640: 900604 48.95 17300 -3300 -39600 887400 51.29 16200 -4400 -52800 874200 53.96 16000 -4600 -55200 871800 54.49 15500 -5100 -61200 865800 55.86 APPENDIX III DEMAGED STABILITY i BASELINE CONFIGURATION iii WBSS 30 CONFIGURATION VESSEL NAME BASELINE DATE DAmAGED CONDITION 2 DRAFT 50.00 FEET DISPLACEMENT 20,000.00 TONS @CG 45.00 FEET(ABOVE BASELINE) LCG 0.00 FEET(+= FWD AMIDSHIPS) DAMAGED COMPARTMENTS ID NO. COMPARTMENT PERMEABILITY TANK OUTFLOW DATA FILL DEPTH DENSITY FREE SURFACE (FEET) (FT#/TON) (FT-TONS) 1 COLUMN 1-5 1.00 24.00 35.00 0.0 3 PONTOON 1-S 1.00 0.00 35.00 0.0 DAMAGED SHIP PROPERTIES AFTER OUTFLOW DISPLACEMENT = 19,999.90 TONS LCG = -0.00 FEET VCG = 45.00 FEET TCG = -0.00 FEET TRANSVERSE METACENTER (ZERO DEGREES) = 78.55 FEET METACENTRIC HEIGHT URRIGHT (ZERO DEGREES) = 33.55 FEET HEEL ANGLE RIGHTING ARM DISPLACEMENT LCB DRAFT TRIM ITERATION 0.000 -10.524 19,999.90 3.55 68.14 -55.98 26 10.000 -5.754 19,999.90 6.64 63.29 -59.75 11 20.000 -0.495 19,999.90 5.55 64.39 -53.42 7 30.000 8.749 19,999.90 4.18 66.10 -46.01 12 40.000 14.749 19,999.90 4.07 76.55 -58.02 10 DAMAGED STABILITY VESSEL NAME BASELINE DATE VESSEL OFFSET FILE NAME MSV-A1 DAMAGED COMPARTMENT FILE MSV-D1 DAMAGED CONDITION 1 DRAFT 50.00 FEET DISPLACEMENT 20,000.00 TONS VCG 45.00 FEET(ABOVE BASELINE) LCG 0.00 FEET(+= FWD AMIDSHIPS) DAMAGED COMPARTMENTS ID NO. COMPARTMENT PERMEABILITY TANK OUTFLOW DATA FILL DEPTH DENSITY FREE SURFACE (FEET) (FT@/TON) (FT-TONS) 1 COLUMN 1-5 1.00 24.00 35.00 0.0 DAMAGED SHIP PROPERTIES AFTER OUTFLOW DISPLACEMENT = 19,999.97 TONS LCG = -0.00 FEET VCG = 45.00 FEET TOG s -0.00 FEET TRANSVERSE METACENTER (ZERO DEGREES) = 45.05 FEET METACENTRIC HEIGHT UPRIGHT (ZERO DEGREES) = 0.05 FEET HEEL ANGLE RIGHTING ARM DISPLACEMENT LCS DRAFT TRIM ITERATION 0.000 -3.748 19,999.97 2.80 57.36 -33.86 19 10.000 -3.044 19,999.97 5.08 58.21 -43.46 9 20.000 0.408 19,999.97 3.22 57.66 -28.99 7 30.000 13.630 19,999.97 1.57 57.91 -15.93 9 40.000 22.241 19,999.97 1.71 68.69 -22.49 10 DAMAGED STABILITY VESSEL NAME 30DEG WIDE DATE VES@EL OFFSET FILE NAME MSV-A5 DAMAGED COMPARTMENT FILE MSV-D@ DAMAGED COMDITION 1 DRAFT 50.00 FEET DISPLACEMENT 20,600.00 TONS VCG 45.00 FEET(ABOVE BASELINE) LCG 0.00 FEET(+= FWD AMIDSHIPS) DAMAGED COMPARTMENTS ID NO. COMPARTMENT PERMEABILITY TANK OUTFOLW DATA FILL DEPTH DENSITY FREE SURFACE (FEET) (FT3/TON) (FT-TONS) 1 COLU@@ 1-@ 1.00 24.00 35.00 0.0 DAMAGED SHIP PROPERTIES AFTER OUTFLOW DISPLACEMENT = 20,599.97 TONS LCG = -0.00 FEET VCG = 45.00 FEET TCG = -0.00 FEET TRANSVERSE HETACENTE@ (ZERO DEGREES) = 64.93 FEET METACENTRIC HEIGHT UPRIGHT (ZERO DEGREES) = 19.93 FEET HEEL ANGLE RIGHTING ARM DISPLACEMENT LC8 DRAFT TRIM ITERATION 0.000 -5.301 20,599.97 2.57 57.27 -31.76 18 10.000 -0.@71 20,599.97 4.76 59.77 -40.39 8 20.000 @.578 20,599.97 2.34 63.08 -20.50 7 30.000 25.501 20,599.97 1.92 71.28 -19.73 6 40.000 38.704 20,599.97 2.06 91.99 -27.35 14 VE@SEL NAME 30DEG WIDE DATE CAMAGED CONDITION 2 DRAFT 50.00 FEET DISPLACEMENT 20,600.00 TONS VCG 45.00 FEET(ABOVE BASELINE) LCG 0.00 FEET(+= FWD AMIDSHIPS) DAMAGED COMPARTMENTS ID NO. COMPARTMENT PERMEABILITY TANK OUTFLOW DATA FILL DEPTH DENSITY FREE SURFACE (FEET) (FT3/TON) (FT-TONS) 1 COLUMN 1-S 1.00 24.00 35.00 0.0 3 PONTOON 1-S 1.00 0.00 35.00 0.0 DAMAGED SHIP PROPERTIES AFTER OUTFLOW DISPLACEMENT = 20,599.89 TONS LCG = -0.00 FEET VCG = 45.00 FEET TCG = -0.00 FEET TRANSVERSE METACENTER (ZERO DEGREES) = 95.75 FEET METACENTRIC HEIGHT URRIGHT (ZERO DEGREES) = 50.75 FEET HEE@ ANGLE RIGHTING ARM DISPLACEMENT LCB DRAFT TRIM ITERATION 0.000 -15.131 20,599.89 3.41 65.08 -54.84 23 10.000 -6.888 20,599.89 6.21 64.49 -55.04 7 20.000 4.832 20,599.89 4.46 68.09 -41.49 10 30.000 22.156 20,599.89 3.91 77.10 -42.71 9 40.000 26.938 20,599.89 3.73 96.54 -52.33 16

Claims: CLAIMS: 1. A wide based semi-submersible vessel comprising a deck, a plurality of stability columns extending downwardly and outwardly from the deck, means connected to the lower ends of the stability columns for providing a wide buoyant base, and means for discharging and taking on ballast. 2. The vessel of claim 1 wherein the base-providing means comprises a pair of longitudinally elongated pontoons connected to the lower ends of the stability columns on each side of the vessel. 3. The vessel of claim 1 or 2 wherein the base-providing means comprises a footing connected to the lower end of each one of the stability columns. 4. The vessel of claim 2 wherein the deck is includes longitudinally extending sponsons extending downwardly from each of the port and starbord sides of the deck, the inner surface of each of the sponsons extending downwardly and outwardly from the bottom of the deck. 5. The vessel of claim 4 wherein the inner surface of each of the sponsons extends downwardly and outwardly from the bottom of the deck at the same angle as the columns extend downwardly and 'outwardly. 6. The vessel of claim 1 wherein the columns extend downwardly and outwardly at an angle of greater than Do to less than 900. 7. The vessel of claim 6 wherein said columns extend downwardly and outwardly at an angle of greater than Do to about 300 from vertical. 8. A method of breaking an ice mass with a wide based semi-submersible vessel comprising a deck, a plurality of stability columns extending downwardly and outwardly from the deck, and means connected to the lower ends of the stability columns for providing a wide buoyant base, the method including the step of discharging and taking on ballast for the vessel to bring the stability columns into contact with the ice mass. 9. The method of claim 8 wherein the buoyancy of said vessel is continuously changed to have the vessel rise and settle.

Inventors: DAHAN, PAUL CHRISTIAN
Applicants: MOBIL OIL CORPORATION
Application year: 1984
Main classification: B63B35
IPC codes: B63B35, B63B43