Specimen examination papers 409 Present displacement 5400 t, which includes the following: Inclining weight 25 t, Kg 7.94 m. Fuel oil 50 t, Kg 2.30 m, FSM 640 t m. The inclining weight is moved 14.0 m transversely producing a de¯ection of 27 cm in a plumbline of length 9.0 m. (20) DATASHEET Q.1 (This Datasheet must be returned with your answer book). Note `foap' denotes for'd of AP Hydrostatic Particulars `A' Draught Displacement TPC MCTC KM T KB LCB LCF m t t t m foap foap SW FW SW FW SW FW RD 1.025 RD 1.000 RD 1.025 RD 1.000 RD 1.025 RD 1.000 m m m m 7.00 14 576 14 220 23.13 22.57 184.6 180.1 8.34 3.64 70.03 67.35 6.90 14 345 13 996 23.06 22.50 183.0 178.5 8.35 3.58 70.08 67.46 6.80 14 115 13 771 22.99 22.43 181.4 177.0 8.36 3.53 70.12 67.57 6.70 13 886 13 548 22.92 22.36 179.9 175.5 8.37 3.48 70.16 67.68 6.60 13 657 13 324 22.85 22.29 178.3 174.0 8.38 3.43 70.20 67.79 6.50 13 429 13 102 22.78 22.23 176.8 172.5 8.39 3.38 70.24 67.90 6.40 13 201 12 879 22.72 22.17 175.3 171.0 8.41 3.33 70.28 68.00 6.30 12 975 12 658 22.66 22.11 173.9 169.6 8.43 3.28 70.32 68.10 6.20 12 748 12 437 22.60 22.05 172.5 168.3 8.46 3.22 70.35 68.20 6.10 12 523 12 217 22.54 21.99 171.1 167.0 8.49 3.17 70.38 68.30 6.00 12 297 11 997 22.48 21.93 169.8 165.7 8.52 3.11 70.42 68.39 5.90 12 073 11 778 22.43 21.87 168.5 164.4 8.55 3.06 70.46 68.48 5.80 11 848 11 559 22.37 21.82 167.3 163.2 8.59 3.01 70.50 68.57 5.70 11 625 11 342 22.32 21.77 166.1 162.1 8.63 2.95 70.53 68.65 5.60 11 402 11 124 22.26 21.72 165.0 161.0 8.67 2.90 70.57 68.73 5.50 11 180 10 908 22.21 21.66 163.9 160.0 8.71 2.85 70.60 68.80 5.40 10 958 10 691 22.15 21.61 162.9 158.9 8.76 2.80 70.64 68.88 5.30 10 737 10 476 22.10 21.56 161.8 157.9 8.81 2.74 70.68 68.95 5.20 10 516 10 260 22.05 21.51 160.8 156.9 8.86 2.69 70.72 69.02 5.10 10 296 10 045 22.00 21.46 159.8 155.9 8.92 2.63 70.75 69.09 5.00 10 076 9830 21.95 21.41 158.8 154.9 8.98 2.58 70.79 69.16 4.90 9857 9616 21.90 21.36 157.9 154.0 9.06 2.53 70.82 69.23 4.80 9638 9403 21.85 21.32 156.9 153.1 9.13 2.48 70.86 69.29 4.70 9420 9190 21.80 21.27 156.0 152.2 9.22 2.43 70.90 69.35 4.60 9202 8978 21.75 21.22 155.1 151.3 9.30 2.38 70.93 69.42 4.50 8985 8766 21.70 21.17 154.2 150.5 9.40 2.32 70.96 69.48 4.40 8768 8554 21.65 21.12 153.3 149.6 9.49 2.27 71.00 69.55 4.30 8552 8344 21.60 21.07 152.4 148.7 9.60 2.22 71.04 69.62 4.20 8336 8133 21.55 21.02 151.5 147.8 9.71 2.17 71.08 69.68 4.10 8121 7923 21.50 20.97 150.6 146.9 9.83 2.12 71.12 69.74 4.00 7906 7713 21.45 20.93 149.7 146.0 9.96 2.07 71.15 69.81 3.90 7692 7505 21.40 20.88 148.7 145.1 10.11 2.01 71.18 69.88 3.80 7478 7296 21.35 20.83 147.8 144.2 10.25 1.96 71.22 69.94 3.70 7265 7088 21.30 20.78 146.8 143.3 10.41 1.91 71.25 70.00 3.60 7052 6880 21.24 20.72 145.9 142.3 10.57 1.86 71.29 70.07 3.50 6840 6673 21.19 20.67 144.9 141.3 10.76 1.81 71.33 70.14 THESE HYDROSTATIC PARTICULARS HAVE BEEN DEVELOPED WITH THE VESSEL FLOATING ON EVEN KEEL 412 Ship Stability for Masters and Mates DATASHEET Q.1 (N.B. This Datasheet must be returned with your examination answer book) TABULATED KN VALUES `A' KN values in metres KN values calculated for vessel on an Even Keel and ®xed trim. Displacement Angle of Heel (Degrees) (tonne) 12 20 30 40 50 60 75 15 000 1.72 2.98 4.48 5.72 6.48 6.91 7.05 14 500 1.73 2.98 4.51 5.79 6.58 6.95 7.08 14 000 1.74 2.98 4.55 5.85 6.68 7.00 7.10 13 500 1.75 2.99 4.58 5.90 6.73 7.08 7.13 13 000 1.77 3.00 4.62 5.93 6.78 7.14 7.16 12 500 1.78 3.03 4.63 5.98 6.83 7.18 7.18 12 000 1.78 3.05 4.65 6.04 6.88 7.20 7.20 11 500 1.80 3.12 4.70 6.10 6.93 7.25 7.22 11 000 1.82 3.15 4.75 6.15 6.98 7.30 7.24 10 500 1.83 3.19 4.79 6.18 7.02 7.35 7.27 10 000 1.86 3.23 4.83 6.22 7.07 7.40 7.30 9500 1.93 3.28 4.91 6.25 7.11 7.45 7.35 9000 2.00 3.36 5.00 6.28 7.18 7.50 7.40 8500 2.05 3.43 5.04 6.32 7.20 7.55 7.41 8000 2.10 3.52 5.10 6.36 7.22 7.60 7.42 7500 2.17 3.62 5.18 6.38 7.24 7.65 7.46 7000 2.22 3.70 5.25 6.40 7.26 7.70 7.50 6500 2.32 3.85 5.35 6.43 7.27 7.70 7.51 6000 2.42 4.00 5.45 6.48 7.28 7.70 7.52 5500 2.57 4.15 5.55 6.53 7.29 7.68 7.51 5000 2.72 4.32 5.65 6.58 7.30 7.66 7.50 KN values are for hull and forecastle only. Specimen examination papers 413 SHIP STABILITY Attempt ALL questions Marks for each question are shown in brackets 1. Ship `A' has a displacement of 14 000 tonne and a KG of 8.20 m. Using Datasheets Q.1 Tabulated KN Values and Hydrostatic Particulars, determine whether the vessel complies with the stability requirements of the current Load Line Rules. (35) 2. A box shaped vessel ¯oating at an even keel in salt water has the following particulars: Length 75.00 m Breadth 18.00 m Depth 11.0 m Draft 6.00 m KG 6.80 m An empty midship watertight compartment 15.00 m long is bilged. Calculate EACH of the following: (a) the new draft; (8) (b) the GM in the ¯ooded condition; (12) (c) the righti ng moment at an angle of 16 degrees. (15) 3. (a) Describe, with the aid of a sketch, the forces that cause a vessel to heel when turning. (12) (b) A vessel turns in a circle of diameter 200 m at a speed of 16 knots. GM 0.78 m. BG 0.88 m. g  9.81 m/sec 2 (Assume 1 knot  1.8532 km/hr). Calculate the angle of heel due to turning. (18) 4. (a) Describe the hydrostatic, stability and stress data required to be supplied to ships. (30) (b) A maximum draft forward is sometimes stated in the above data when supplied to the ship under the Load Line Rules. State the reason for this limitation. (5) 5. A vessel with a high deck cargo will experience adverse effects on its stability due to strong beam winds on lateral windage areas. With the aid of a sketch, show the minimum stability requirements, with respect to wind heeling, under current regulations. (35) 6. With regard to the inclining experiment: (a) state its purpose; (5) (b) describe the precautions to be taken before and during the experiment; (16) (c) list the circumstances when the experiment is required to take place. (9) COMMAND ENDORSEMENT (LIMITED EUROPEAN) Ship Construction and Stability 2 hours. Attempt all questions. Marks for each question are shown in brackets. 1. A ship has a light displacement 435 tonnes with KG 3.25 m. On board this ship there are 40 tonnes of fuel, water, stores and crew effects at Kg 3.80 m with a free surface moment of 35 t m. The single hold is rectangular of length 40 m, width 9.4 m and depth 5.1 m and is to be ®lled with a bulk cargo (stowage factor 1.4 m 3 /tonne). When ®lled the Kg of the hold is 3.34 m. Calculate the GM of the ship in its loaded condition if the loaded KM is 4.05 m (30) 2. A ship is at displacement 1700 tonnes with draughts 3.20 m forward 4.05 m aft. The following is the appropriate hydrostatic data: Length BP: 55 m TPC: 5.2 MCTC: 22.8 Centre of Flotation 2.5 m abaft amidship. Calculate: (a) the drafts forward and aft produced by loading 100 tonnes 40 m forward of the aft perpendicular; (20) (b) from the initial condition, the weight to load 37 m forward of the aft perpendicular to bring the ship to a trim of 0.6 m by the stern. 3. Use Worksheet Q.3: Simpli®ed Stability ± Deadweight Moment Curve. (Ensure that all points plotted on the diagram can be identi®ed in the working). The load displacement is 1175 tonnes. The ships present condition: displacement 800 tonnes. Deadweight moment 600 t m. Cargo to be loaded: 250 tonnes at Kg 2.8 m. From the above condition: (a) Determine the maximum weight of cargo that can be taken at Kg 4.5 m so that stability is adequate. (10) (b) It is anticipated that 30 tonnes of fuel and water at Kg 1.6 m will be used on passage producing a free surface moment of 100 t m. Determine the maximum weight of cargo that can be loaded at Kg 4.5 m so that stability is adequate on arrival at the discharge port. (20) 4. (a) Explain clearly the meaning of the term `reserve buoyancy'. (15) (b) Describe the items that maintain the integrity of reserve buoyancy giving a brief indication of any maintenance that may be required. (15) 5. (a) (i) Sketch a typical GZ curve for a stable ship and indicate the features that may be found from it. (15) (ii) The ship in (a) (i) is now further loaded with deck cargo. Show on the same curve how the GZ might change due to this. (7) 414 Ship Stability for Masters and Mates (b) A ship is at a certain draught and displacement. Sketch two GZ curves on the same axes to show this ship in a stiff and a tender condition. (8) WORKSHEET Q.3 (N.B. The Worksheet must be returned with your examination answer book. Ensure that all points plotted on the diagram can be identi®ed in the working) COMMAND ENDORSEMENT (EXTENDED EUROPEANS) Ship Construction and Stability 3 hours. Attempt all questions. Marks for each question are shown in brackets. 1. A ship has a light displacement of 2700 tonnes and KG 6.50 m. The load displacement of 11 800 tonnes has an associated KM 6.60 m. The following are to be taken on board: Fuel and FW: 520 tonnes at Kg 0.60 m Stores: 100 tonnes at Kg 4.50 m A full cargo is then to be loaded in the tween deck at Kg 8.20 m and hold at Kg 5.00 m to give a sailing GM of 1.00 m. Specimen examination papers 415 Calculate how much of the cargo should be loaded in the: (i) tween deck; (ii) hold (35) 2. The GZ values of a vessel at a certain displacement are as shown: Heel (y  ) 0 15 30 45 60 75 GZ (m) 0 0.27 0.73 0.95 0.61 0.06 KM: 9.00 m KG 8.20 m (a) Plot the GZ curve on the graph paper provided. (10) (b) Calculate the area under the curve between 0  and 30  using Simpson's Rules. (15) (c) Show that the curve satis®es the stability criteria required by the Load Line Rules 1968. (10) 3. MV Mexna (2) is ¯oa ting at draughts 6.40 m forward and 7.60 m aft. Using the hydrostatic data provided (Worksheet Q.3) calculate: (a) the amount of ballast to load into the forepeak tank (c.g. 60 m forward of amid-ships) so that the draught aft is 7.30 m; (25) (b) the ®nal draught forward. (10) 4. Explain with reference to a well labelled sketch, how the effect of free surface can be considered as a reduction in a vessel's metacentric height. (35) 5. (a) List the requirements of the Load Line Rules 1968, relating to weathertight doors. (10) (b) Describe the maintenance and testing of a superstructure door in order to ensure weathertightness. (20) 6. Illustrate by means of labelled half mid-section sketches each of the following framing systems: (i) Transverse; (10) (ii) Longitudinal; (10) (iii) Combination. (10) 416 Ship Stability for Masters and Mates WORKSHEET Q.3 Hydrostatic Curves for Mexna (2) (N.B. This worksheet must be returned with your answer book) COMMAND ENDORSEMENT (EXTENDED EUROPEAN) DATASHEET Q.5 This Datasheet must be returned with your answer book HYDROSTATIC PARTICULARS `B' (in salt water R.D. 1.025) The hydrostatic particulars have been calculated for the vessel on Even Keel. Draught (m) Displacement (t) TPC (t) MCTC (tm) LCB from LCF from KB (m) KM T (m) amidships (m) amidships (m) 4.00 1888.8 5.20 23.30 1.45 A 2.39 A 2.09 4.05 3.90 1836.8 5.20 23.20 1.42 A 2.43 A 2.04 4.05 3.80 1784.8 5.19 23.10 1.39 A 2.46 A 1.99 4.05 3.70 1733.0 5.18 22.99 1.36 A 2.49 A 1.93 4.06 3.60 1681.2 5.17 22.89 1.32 A 2.52 A 1.88 4.06 3.50 1629.5 5.16 22.77 1.29 A 2.55 A 1.83 4.07 3.40 1577.9 5.16 22.65 1.24 A 2.57 A 1.78 4.09 3.30 1526.4 5.15 22.52 1.20 A 2.59 A 1.72 4.11 3.20 1475.1 5.13 22.39 1.15 A 2.61 A 1.67 4.13 3.10 1423.8 5.12 22.25 1.10 A 2.62 A 1.62 4.15 3.00 1372.6 5.11 22.11 1.04 A 2.63 A 1.56 4.19 2.90 1321.5 5.10 21.96 0.98 A 2.64 A 1.51 4.22 2.80 1270.6 5.09 21.80 0.91 A 2.64 A 1.46 4.27 2.70 1211.4 5.07 21.64 0.84 A 2.64 A 1.40 4.32 2.60 1169.1 5.06 21.47 0.76 A 2.63 A 1.35 4.37 2.50 1118.6 5.05 21.30 0.68 A 2.63 A 1.30 4.44 2.40 1068.4 5.01 20.87 0.59 A 2.51 A 1.24 4.51 [...]... 3 .52 3.62 3.70 3. 85 4.00 4. 15 4.32 4.48 4 .51 4 .55 4 .58 4.62 4.63 4. 65 4.70 4. 75 4.79 4.83 4.91 5. 00 5. 04 5. 10 5. 18 5. 25 5. 35 5. 45 5 .55 5. 65 5.72 5. 79 5. 85 5.90 5. 93 5. 98 6.04 6.10 6. 15 6.18 6.22 6. 25 6.28 6.32 6.36 6.38 6.40 6.43 6.48 6 .53 6 .58 6.48 6 .58 6.68 6.73 6.78 6.83 6.88 6.93 6.98 7.02 7.07 7.11 7.18 7.20 7.22 7.24 7.26 7.27 7.28 7.29 7.30 6.91 6. 95 7.00 7.08 7.14 7.18 7.20 7. 25 7.30 7. 35 7.40... 1733.0 1681.2 1629 .5 157 7.9 152 6.4 14 75. 1 1423.8 137 2.6 132 1 .5 1270.6 1211.4 1169.1 1118.6 1068.4 5. 20 5. 20 5. 19 5. 18 5. 17 5. 16 5. 16 5. 15 5 .13 5. 12 5. 11 5. 10 5. 09 5. 07 5. 06 5. 05 5.01 23.30 23.20 23.10 22.99 22.89 22.77 22. 65 22 .52 22.39 22. 25 22.11 21.96 21.80 21.64 21.47 21.30 20.87 LCB from amidships (m) 1. 45 1.42 1.39 1.36 1.32 1.29 1.24 1.20 1. 15 1.10 1.04 0.98 0.91 0.84 0.76 0.68 0 .59 A A A A A A... 162.9 161.8 160.8 159 .8 158 .8 157 .9 156 .9 156 .0 155 .1 154 .2 153 .3 152 .4 151 .5 150 .6 149.7 148.7 147.8 146.8 1 45. 9 144.9 160.0 158 .9 157 .9 156 .9 155 .9 154 .9 154 .0 153 .1 152 .2 151 .3 150 .5 149.6 148.7 147.8 146.9 146.0 1 45. 1 144.2 143.3 142.3 141.3 8.71 8.76 8.81 8.86 8.92 8.98 9.06 9 .13 9.22 9.30 9.40 9.49 9.60 9.71 9.83 9.96 10.11 10. 25 10.41 10 .57 10.76 2. 85 2.80 2.74 2.69 2.63 2 .58 2 .53 2.48 2.43 2.38... 6 .50 6.40 6.30 6.20 6.10 6.00 5. 90 5. 80 5. 70 5. 60 14 57 6 14 3 45 14 1 15 13 886 13 657 13 429 13 201 12 9 75 12 748 12 52 3 12 297 12 073 11 848 11 6 25 11 402 14 220 13 996 13 771 13 54 8 13 324 13 102 12 879 12 658 12 437 12 217 11 997 11 778 11 55 9 11 342 11 124 TPC t SW RD 1.0 25 23 .13 23.06 22.99 22.92 22. 85 22.78 22.72 22.66 22.60 22 .54 22.48 22.43 22.37 22.32 22.26 MCTC tm FW SW RD 1.000 RD 1.0 25 22 .57 ... 70.32 70. 35 70.38 70.42 70.46 70 .50 70 .53 70 .57 67. 35 67.46 67 .57 67.68 67.79 67.90 68.00 68.10 68.20 68.30 68.39 68.48 68 .57 68. 65 68.73 8.34 8. 35 8.36 8.37 8.38 8.39 8.41 8.43 8.46 8.49 8 .52 8 .55 8 .59 8.63 8.67 5. 50 5. 40 5. 30 5. 20 5. 10 5. 00 4.90 4.80 4.70 4.60 4 .50 4.40 4.30 4.20 4.10 4.00 3.90 3.80 3.70 3.60 3 .50 11 180 10 958 10 737 10 51 6 10 296 10 076 9 857 9638 9420 9202 89 85 8768 855 2 8336 8121... calculated for vessel on an Even Keel and ®xed trim Displacement (tonne) 15 000 14 50 0 14 000 13 50 0 13 000 12 50 0 12 000 11 50 0 11 000 10 50 0 10 000 950 0 9000 850 0 8000 750 0 7000 650 0 6000 55 00 50 00 Angle of Heel (Degrees) 12 20 30 40 50 60 75 1.72 1.73 1.74 1. 75 1.77 1.78 1.78 1.80 1.82 1.83 1.86 1.93 2.00 2. 05 2.10 2.17 2.22 2.32 2.42 2 .57 2.72 2.98 2.98 2.98 2.99 3.00 3.03 3. 05 3.12 3. 15 3.19 3.23... 1 and 47.9 tonnes from No 4 11 3.118 m F 4.340 m A 12 5. 50 m F 5. 56 m A 13 5. 679 m F 5. 901 m A 14 4 metres aft 15 3.78 metres aft 16 4.44 metres aft 17 55 .55 6 metres forward 18 276. 75 tonnes; 13. 6 metres forward 19 300 tonnes; 6.3 m 20 200 tonnes; 7.6 m 21 4 05 tonnes in No 1 and 1 95 tonnes in No 4 22 214.3 tonnes 23 2 15. 4 tonnes; 5. 96 m F 24 200 metres 25 240 metres 26 Draft aft is 8.23 m Draft forward... A A A LCF from amidships (m) 2.39 2.43 2.46 2.49 2 .52 2 .55 2 .57 2 .59 2.61 2.62 2.63 2.64 2.64 2.64 2.63 2.63 2 .51 A A A A A A A A A A A A A A A A A KB (m) KMT (m) 2.09 2.04 1.99 1.93 1.88 1.83 1.78 1.72 1.67 1.62 1 .56 1 .51 1.46 1.40 1. 35 1.30 1.24 4. 05 4. 05 4. 05 4.06 4.06 4.07 4.09 4.11 4 .13 4. 15 4.19 4.22 4.27 4.32 4.37 4.44 4 .51 426 Ship Stability for Masters and Mates GENERAL SHIP KNOWLEDGE Attempt... GM ˆ 0.842 m, Arr GM ˆ 0 .58 7 m 7 112.4 tonnes 8 6. 15 m ‡ 0.27 m 6 3 0 H Exercise 21 1 5. 12 m 2 0.222 m 3 0.2 25 m 4 0 .55 8 m 5 0.1 05 m 6 0.109 m 7 0.129 m 8 3 .55 m F 2.01 m A 9 7 .52 9 m F 5. 267 m A 10 6. 25 m F 2.96 m A 11 5. 598 m F 3. 251 m A 12 5. 3 05 m F 4. 859 m A Exercise 22 1 134 4 m tonnes 2 2038.4 m tonnes 4 13. 67 m tonnes 5 107.2 m tonnes 3 1424 m tonnes Exercise 24 1 No; 35 49 H 2 39 14 H 3 Probable... 9 857 9638 9420 9202 89 85 8768 855 2 8336 8121 7906 7692 7478 72 65 7 052 6840 10 908 10 691 10 476 10 260 10 0 45 9830 9616 9403 9190 8978 8766 855 4 8344 8133 7923 7 713 750 5 7296 7088 6880 6673 22.21 22. 15 22.10 22. 05 22.00 21. 95 21.90 21. 85 21.80 21. 75 21.70 21. 65 21.60 21 .55 21 .50 21. 45 21.40 21. 35 21.30 21.24 21.19 21.66 21.61 21 .56 21 .51 21.46 21.41 21.36 21.32 21.27 21.22 21.17 21.12 21.07 21.02 20.97 . 7 .50 650 0 2.32 3. 85 5. 35 6.43 7.27 7.70 7 .51 6000 2.42 4.00 5. 45 6.48 7.28 7.70 7 .52 55 00 2 .57 4. 15 5 .55 6 .53 7.29 7.68 7 .51 50 00 2.72 4.32 5. 65 6 .58 7.30 7.66 7 .50 KN values are for hull and forecastle. 7 .50 650 0 2.32 3. 85 5. 35 6.43 7.27 7.70 7 .51 6000 2.42 4.00 5. 45 6.48 7.28 7.70 7 .52 55 00 2 .57 4. 15 5 .55 6 .53 7.29 7.68 7 .51 50 00 2.72 4.32 5. 65 6 .58 7.30 7.66 7 .50 KN values are for hull and forecastle. 5. 17 22.89 1.32 A 2 .52 A 1.88 4.06 3 .50 1629 .5 5.16 22.77 1.29 A 2 .55 A 1.83 4.07 3.40 157 7.9 5. 16 22. 65 1.24 A 2 .57 A 1.78 4.09 3.30 152 6.4 5. 15 22 .52 1.20 A 2 .59 A 1.72 4.11 3.20 14 75. 1 5. 13