Marine Kit 4 Ship Disaster Investigation Teacher s Manual Contents Teacher s Instructions Check Sheet for Investigation Assessment Sheet Agent s Manual Ship Disaster Cases Answer Key This activity was developed under a grant from the National Shipbuilding Research Program (NSRP)
SHIP DISASTER INVESTIGATION Teacher s Instructions This activity deals with the ship disaster case studies. Hypothetical ship disaster case studies are given to the students. Though the cases are hypothetical, causes behind the disasters are real. Students will play the role of Ship Disaster Investigation Agency s (SDIA) agents, analyze the case, find out the causes behind the disaster and give their suggestions for improvement. In this way they learn about the terminology used in the industry, some ship design and construction fundamentals, and right practices followed in the shipbuilding and shipping industry. Kit Contents Activity kit contains Ship Disaster Investigation Agency s agent guide, check sheet, ship disaster cases and model solutions to the cases. Students need to bring calculator The kit contains material for one group (4-5 students). For additional groups, please make copies of all documents. Set Up This activity requires two class periods. (Day 1 and Day 2) Make copies of check sheets (1 for each group) and disaster case (1 for each group) before starting the activity Ship Disaster cases recommendations Use cases 1 and 2 for Middle School Use cases 3 and 4 for High School Answer key (model solutions) is included in the kit for the teacher. Day 1 Please use the power point presentation for day -1 activity. (10 to 15 min) MarineTech Project Ship Disaster Investigation Lean Institute, ODU May 2011
Form investigation teams with 4-5 students in each. Day-1 activity involves analyzing the case and finding out the reasons behind the ship disaster. (40 45 min) Each Investigation team gets one check sheet and one ship disaster case. Students should start filling the information in the check sheet after reading the case carefully. Students will refer to the agent s guide and identify the possible reasons for the disaster. Students can use calculators if necessary. Please collect all the agent guides and keep them in the kit at the end of the activity. Day 2 All the investigation teams present their findings to the class. Compare the findings with the model answers given in the kit. Explain the real reasons behind the disaster to the class. Use the assessment sheets to assess performance of each group, the group with maximum number of points wins. Check the kit contents for any missing document and place the contents back in the box. General Both the activities can be completed in a block schedule. MarineTech Project Ship Disaster Investigation Lean Institute, ODU May 2011
Check sheet for Investigation 1. Type of ship cargo / container / oil tanker / cruise / chemical tanker ship 2. Length of ship (in meters) = 3. Height of ship (in meters) = 4. Beam of ship (in meters) = 5. Designed draft (in meters) = 6. Number of transverse bulkheads (if applicable) = 7. Number of longitudinal bulkheads (if applicable) = 8. Cargo carrying capacity = 9. Actual cargo at the time of disaster = 10. Type of cargo = 11. Density of cargo (if applicable) = MarineTech Project Ship Disaster Investigation Lean Institute, ODU May 2011
This assessment sheet is to be used by the teacher to evaluate the Ship Disaster Investigation Activity Ship Disaster Investigation Assessment Sheet Group No: Date(mm/dd/yy): Names 1) 2) 3) 4) Poor Fair Good Very Good Excellent Quality Characteristics 1 2 3 4 5 Understanding the nature of the disaster Ability of students to find the clues Ability of students to find the reasons for the disaster Group activity involvement Presenting the findings of the analysis Total Points MarineTech Project Ship Disaster Investigation Lean Institute,ODU May 2011
Marine Kit 4 Marine Kit 4 Sail Smooth, Sail Safe Includes Basic ship Terminologies and Investigation Check list
Index 1. Ship Terminology 03 2. Motions of a Floating Body...09 3. Ship Stability.10 4. Free Surface Effect..13 5. Effect of Water Density on the Draft 15 6. Displacement of Ship..16 7. Loading of Ship...17 8. Tanker Ships....19 9. Speed of Ship....20 10.Ship Power Plant..21 11.SONAR 23 12.Unit Conversions.26 2
1. Ship Terminology Starboard Stern Bow Port Bow : Front part of the ship Stern : Rear part of the ship Starboard : Right side of the ship Port : Left side of the ship 3
Hull Hull is a body of a ship Most of the modern vessels have double hull to prevent flooding in case of accidents. Ship Hull Tankers have double hull to prevent oil spilling in case of hull damage. Double hull also serves as ballast tanks in the partial loaded or unloaded condition to keep the center of gravity as low as possible for stability. Double Hull 4
Various terms used to define hull cross section fore is the front part aft is the rear part Keel Keel of the ship is the principal structural member of a ship running lengthwise along the center line from bow to stern, to which the frames are attached. http://web.nps.navy.mil/~me/tsse/navarchweb/1/module2/introductio n.htm# 5
Cross section of ship Beam Waterline Freeboard Draft Draft of a ship is the vertical distance between the waterline and the bottom of the hull Freeboard of a ship is the vertical distance above the waterline Beam of a ship is the width of a ship at any cross section 6
Deadrise: Deadrise is an angle measured upward from a horizontal plane at the keel level. Deadrise Flat bottomed vessels have 0 (zero) deadrise. Deadrise for V shaped hull varies from bow to stern. Deadrise is very important feature in the stability of the vessel. A flat bottomed boat rises on a plane quickly and provides a stable comfortable ride in calm water but will pound heavily in rough water. A vessel with deadrise provides greater stability and comfort in rough conditions. Ocean going big ships are never flat bottomed in the fore and aft hull sections, may be almost flat bottomed in the mid ship section. Ocean going vessel with full flat bottomed hull may capsize easily in the heavy seas 7
Bulkheads Bulkheads Bulkhead: Bulkhead is a upright wall like structure within the hull of a ship. Bulkheads increase structural rigidity of the vessel Bulkheads create watertight compartments to prevent flooding in case of hull breach or leak. Longitudinal Bulkheads are used to create watertight compartments in case of ship capsize. It also divides cargo into different sections and thus helps improve stability of ship by creating different center of gravities for different sections. (More on this in free surface effect) 8
2. Motions of a floating body Any floating body has three motions namely Roll, Pitch and Yaw Roll: Rolling is the motion of a floating body about the longitudinal axis ( axis along the length of the body) Pitch: Pitching is the motion about the transverse axis of the body (i.e axis along the width of the ship. Yaw: Yawing is the motion of a floating body about the vertical axis. Control of all the three motions is very important for ship stability and ride comfort. 9
3. Ship Stability Center of Gravity (G), Center of Buoyancy (B), and Metacenter (M) play very important role in stability of the ship. The center of buoyancy, is the center of gravity of the volume of water which the hull displaces. This point is referred to as B in naval architecture. The center of gravity of the ship itself is known as G in naval architecture. When a ship is upright, the center of buoyancy is directly below the center of gravity of the ship. 10
Center of Gravity is the point where all the weight of the object can be considered to be concentrated Center of Buoyancy is the center of mass of the immersed part of ship or floating object Metacenter is the point where lines of action of upward buoyancy force intersect When the ship is vertical, it lies above the center of gravity and so moves in the opposite direction of the heel as ship rolls Relationship between G and M G under M: ship is stable G = M: ship neutral G over M: ship unstable M G G B M B Stable Unstable 11
When the cargo in the ship are evenly distributed, the ship will be upright. The sum of the gravity forces of cargo and the ship will be acting at one point - the Center of Gravity, G, acting downwards. Similarly, the Center of Buoyancy of the ship will be acting at one point B, acting upwards. What is stable equilibrium? A ship is said to be in Stable Equilibrium if on being slightly inclined, tends to return back to the original position. However, a ship will be in Unstable Equilibrium when she tends to move further from that original position on being tilted slightly. A ship in Neutral Equilibrium will tend to neither return nor move further from that position. 12
4. What is the free surface effect? This effect proves fatal in partially filled ocean going vessels in the heavy seas. Wave Force of wave heels the ship to the starboard. Center of gravity of oil shifts. Oil acts as a single mass, hence the change in the center of gravity is drastic Force of wave and change in the center of gravity heels the ship more and more without giving it a chance to come to its upright position. As the ultimate effect of wave force and big change in center of gravity ship capsizes. 13
How to minimize the free surface effect? Ship is fitted with compartments, i.e. (longitudinal bulkheads) Now the liquid in the tank acts as different masses and center of gravity of individual mass changes. But effect of changing all the center of gravities does not shift the center of gravity of the ship as significantly as before. The other way to minimize the free surface effect is to fill the tanks nearly full. This does not give the liquid room and hence minimizes the free surface effect. Tanker ships never sail partially filled 14
5. Effect of change in density of water on the draft of a ship Density of Fresh Water = 1000 kg / m 3 Average Density of Sea Water = 1030 kg / m 3 Draft of ship changes with the change in density of water Keeping the load same, change in the draft can be calculated by following equation New Draft OldDraft OldDensity NewDensity Fresh water draft is more than salt water draft Ships transiting between sea water and fresh water have to consider this change in draft to avoid a danger of running aground 15
6. Displacement of ship The word "displacement" arises from the basic physical law, discovered by Archimedes, that the weight of a floating object equates exactly to that of the water displaced Displacement = actual total weight of the vessel Unit of Displacement = long ton or metric ton How to calculate Displacement of ship? 1. Volume of submerged part (cu. Feet) = length * Beam * Draft 2. Multiply this by block coefficient of hull 3. Multiply this figure by 64 to get weight of ship in pounds or divide by 35 to calculate weight in long tons 4. Using SI or metric system: displacement (in tons) is volume (in cubic meters) multiplied by the specific gravity of sea water (nominally 1.025) 16
Plimsoll line or International Load Line the mark on the hull of a ship that shows where the waterline is when the ship is loaded to full capacity according to the condition of the water at the point of loading. Lightship weight is the displacement of the ship only with no fuel, passengers, cargo, water, etc. on board. Full Load Displacement: Displacement when ship is loaded with cargo or people to the point that it is submerged to its load line Deadweight Tonnage (DWT) is full load displacement minus the lightship weight. It includes the crew, passengers, cargo, fuel, water and stores etc. A ship can carry cargo weighing roughly 90% of its deadweight tonnage 17
7. Loading of Ship Cargo should be always evenly distributed Uneven distribution makes ship unstable Uneven distribution also creates stresses on the ship structure Cargo should be properly secured (e.g.in case of cargo like cars) Stowage Factor = Volume of cargo Mass of cargo Proper care should be taken to distribute the load evenly when carrying high density cargo with stowage factor above 0.56 18
8. Tanker Ships Tankers are used to carry liquid and gaseous cargo All the tanker ships have double hull in order to prevent oil leakage Partially filled tankers are highly unstable in heavy seas because of the free surface effect General Arrangement of Cargo and Ballast Tanks for Tankers Slop tanks are provided for storage of dirty ballast residue and tank washings from the cargo tanks 19
9. Speed of ship Speed of a ship is measured in knots Modern ships are powered by diesel engines Some ships are powered by steam turbines also Nuclear power is used in defense naval ships Propeller shaft Propellers Power Source (Diesel Engine / Steam Turbine/ Nuclear power) Loss of propulsion system can prove fatal, especially in heavy seas as ship loses control over direction 20
10. Ship Power Plant Most new ships today are powered by diesel engines, though a few older ships are still powered by steam turbines and reciprocating steam engines Propeller shaft Power Plant (Engine/ turbine) Propeller 21
Power plant and propulsion system are the most critical systems in any ship It gives the ship the force required to move Failure of power plant or propulsion system could be fatal as ship loses control on the direction Loss of power or propulsion in heavy seas or near the shore is very dangerous since ship may stray with the direction of winds and waves and may run aground 22
11. SONAR SONAR (Sound Navigation and Ranging) SONAR is a technique that uses sound propagation under water (primarily) to navigate, communicate or detect other vessels Principle of SONAR: Reflection of sound waves 23
A transmitter is used to transmit the signal A receiver is used to catch the reflection (echo) The time from transmission of a pulse to reception is measured Speed of sound in water is known Distance Using the formula Speed = Time we can calculate the distance of the object from the source of the pulse (transmitter) Distance d Time t SEA BED 24
Speed of sound in water is calculated using following equation Speed of Sound (feet /s) = 4388 + (11.25 temperature (in F)) + (0.0182 depth (in feet) + salinity (in parts-per-thousand)). 1 foot = 0.3048 meters Distance from the object is calculated using formula Distance = Speed of sound x time between transmission and reception 2 25
12. Unit Conversions 1 Metric ton = 2204.62 pounds = 1000 kilogram 1 long ton = 2240 pounds = 1016.05 kilogram 1 meter = 3.281 feet 1 knot = 1.151 miles / hour = 1.852 kilometer / hour 1 nautical mile = 1.151 miles = 1.852 kilometer 746 horsepower = 1 Watt = 1 Joule / second 26
Ship Disaster Investigation Ship Disaster Case 1 MV Safesail, a 199 meter 9500 ton DWT cargo ship sank on its maiden voyage across Atlantic, 130 miles off the Virginia coast on June 25. Three out of 25 crew members were rescued, who witnessed the sinking of the ship. They told that the ship encountered heavy seas, listed dangerously to starboard and capsized. Seaworthy shipping company, owner of the MV Safesail issued a press release saying that apart from the 5267 tons of trash for recycling, the ship was carrying 60 trailer-trucks and 3000 cars across the Atlantic. Rescued crew members were quoted saying that the cars were loaded on the top 3 decks and were not secured with the chains to the deck. Many questions are being raised on the tragic disaster by the families of the deceased crew members. Preliminary reports said that the vessel had faulty design; it was overloaded and improperly loaded. Specifications of the ill-fated vessel: Length: 199 meter Width: 32 meter Draft: 9 meter Cargo carrying capacity: 9500 ton Standard tractor-trailer weight: 8 ton Standard car weight: 1.5 ton MarineTech Project Ship Disaster Investigation Lean Institute, ODU May 2011
Ship Disaster Investigation Ship Disaster Case 2 220,966 DWT oil tanker ship MV Ölsee en-route to Japan sank 250 miles off the Alaskan coast on June 6 after colliding with iceberg causing major threat to flora and fauna in the surrounding region because of the oil spread. According to the initial information received, the tanker was carrying 90,000 tons of crude oil. The heavy Alaskan seas caused excessive rolling due to which the vessel lost control and collided with the iceberg. An inquiry has been ordered into the disaster. SDIA agents will investigate the disaster and submit the report to the Seaworthy shipping company, the owner of the ill-fated ship. Specifications of the ill-fated vessel: Length: 287.25 meter Width: 50 meter Draft: 28 meter Cargo carrying capacity: 220,966 ton Hull Type: single hull (Mono-hull) Longitudinal Bulkheads (along the length of ship) = 0 Transverse Bulkheads (along the width of ship) = 10 MarineTech Project Ship Disaster Investigation Lean Institute, ODU May 2011
Ship Disaster Investigation Ship Disaster Case 3 MV Chemstar, 182.9 meter single hull chemical tanker ship broke apart southeast of Nantucket Island, Massachusetts on December 15, causing one of the largest chemical spills in the history. She was carrying Trochlorotrifluoroethane in the first three tanks and petroleum ether in the tank number 5, 6 and 7. The ship reported excessive rolling and pitching due to heavy seas. Distress call also reported cracks developed in the hull near tank number 4. Specifications of the ill-fated vessel: Length: 182.9 meter Width: 32.2 meter Depth: 20 meter Draft: 12.18 meter Total volume of chemical tanks: 52,969 cubic meters Density of Trochlorotrifluoroethane: 1564 kg / cubic meter Density of Petroleum ether: 640 kg / cubic meter The above figure shows layout of MV Chemstar MarineTech Project Ship Disaster Investigation Lean Institute, ODU May 2011
Ship Disaster Investigation Ship Disaster Case 4 On 8 January 2005, a submarine Deep Blue Ocean, while on its way to a deep sea research mission in the North Pacific Ocean, ran aground, approximately 350 nautical miles South of Guam in the middle of the East Marianas Basin. This submarine is owned by amateur oceanographers in the U.S. The incident reportedly caused death of one sailor and critical injuries to 23 of the submarines crew and oceanographers. Deep Blue Ocean, while transiting at the flank (maximum) speed of 35 knots and submerged to 525 feet, hit a seamount. Primary information reveals that the navigation officer made a serious mistake in the calculation of position of the seamount. An inquiry has been ordered to investigate the incidence. SDIA agents will find the causes behind the incidence. The operating conditions at the time of incidence were reported in the log book. Water temperature: 45 0 F Salinity of water: 34 parts per thousand SONAR log showed that the time between transmission and reception of signal before an accident was 2 seconds. The orders for changing the path of the vessels were given 10 seconds after the detection of seamount. This submarine requires 150 seconds to change its path. The last entry in the SONAR log for the distance of seamount was 3023 meters. MarineTech Project Ship Disaster Investigation Lean Institute, ODU May 2011
Ship Specifications: Ship Disaster Investigation Report Write N.A. if data is not given 1) Length of ship (in meters) = 2) Height of ship (in meters) = 3) Beam of ship (in meters) = 4) Type of ship Cargo / Container / Oil tanker / Cruise / Chemical Tanker Ship 5) Cargo carrying capacity (in tons) = Real Time Data (at the time of disaster): 1) Date of the disaster: 2) Actual cargo weight at the time of disaster (in tons) = 3) Type of cargo the ship was loaded with = 4) Weather conditions = Reason/s for the disaster (one or more reasons may be present): Reason 1: Reason 2: MarineTech Project Ship Disaster Investigation Lean Institute ODU May 2011
Reason 3: Any other factors (if any) that contributed to the disaster: Any suggestions for improvement a) safety in ship operations and / or b) ship design and / or c) ship construction Prepared by: 1) Agent 2) Agent 3) Agent 4) Agent Date: MarineTech Project Ship Disaster Investigation Lean Institute ODU May 2011
Ship Specifications: Ship Disaster Investigation Report Answer Key MV Safesail (Case 1) 1) Length of ship (in meters) = 199 2) Height of ship (in meters) = Not mentioned 3) Beam of ship (in meters) = 32 (width) 4) Draft (in meters) = 9 5) Type of ship Cargo / Container / Oil tanker / Cruise / Chemical Tanker Ship 6) Cargo carrying capacity (in tons) = 9500 Real Time Data (at the time of disaster): 1) Date of the disaster: June 25 2) Actual cargo weight at the time of disaster (in tons) = 5267+60*8 + 3000*1.5= 10247 3) Type of cargo the ship was loaded with = cars, tractor-trailers, trash 4) Weather conditions = heavy seas Reason/s for the disaster (one or more reasons may be present): Reason 1: Overloading The ship was carrying 3000 cars, 60 tractor-trailers, and trash for recycling at the time of disaster. Each car weighs 1.5 tons and a tractor-trailer weighs 8 tons. In addition to this she was carrying 5267 tons of trash for recycling. The total weight of cargo at the time of disaster was 10,247 tons. This is 747 tons more than the cargo carrying capacity of the ship. This overloading contributed to the sinking of MV Safesail. Reason 2: The cars on the top 3 decks were not secured properly to the decks. The excessive rolling due to the heavy seas caused these cars move toward starboard. This changed the position of center of gravity substantially to the right side of the ship. Eventually ship lost control and capsized. MarineTech Project Ship Disaster Investigation Lean Institute, ODU May 2011
Any other factors (if any) that contributed to the disaster: Any suggestions for improvement a) safety in ship operations and b) ship design and c) ship construction The cargo should be properly secured on the deck. A ship should not be overloaded. Prepared by: 1) Agent 2) Agent 3) Agent 4) Agent Date: MarineTech Project Ship Disaster Investigation Lean Institute, ODU May 2011
Ship Specifications: Ship Disaster Investigation Report Answer Key MV Ölsee (Case 2) 1) Length of ship (in meters) = 287.25 2) Height of ship (in meters) = Not mentioned 3) Beam of ship (in meters) = 50 (width) 4) Draft (in meter) = 28 5) Type of ship Cargo / Container / Oil tanker / Cruise / Chemical Tanker Ship 6) Cargo carrying capacity (in tons) = 220,966 Real Time Data (at the time of disaster): 1) Date of the disaster: June 6 2) Actual cargo weight at the time of disaster (in tons) = 90000 3) Type of cargo the ship was loaded with = Crude Oil 4) Weather conditions = heavy seas, iceberg Reason/s for the disaster (one or more reasons may be present): Reason 1: Partially loaded ship The ship was carrying 90,000 tons of oil. The cargo carrying capacity of the ship was 220,966 tons. So the oil tanker was partially loaded. Free surface comes into picture in case of partially filled tanker ships. The ship did not have longitudinal bulkheads. (Longitudinal bulkheads are used to reduce free surface effect). Absence of longitudinal bulkheads and partial loading of the ship caused excessive rolling in heavy Alaskan seas, ship lost control over its direction and collided with an iceberg. Reason 2: The ship had a mono-hull (single hull) design. The ship could have survived, if had a double hull. Double hull increases damage stability and also prevents oil spillages. MarineTech Project Ship Disaster Investigation Lean Institute, ODU May 2011
Any other factors (if any) that contributed to the disaster: Any suggestions for improvement a) safety in ship operations and b) ship design and c) ship construction Tanker ships should have double hull. Tanker ships never sail partially filled, if so proper ballasting should be done. Prepared by: 1) Agent 2) Agent 3) Agent 4) Agent Date: MarineTech Project Ship Disaster Investigation Lean Institute, ODU May 2011
Ship Specifications: Ship Disaster Investigation Report Answer Key MV Chemstar (Case 3) 1) Length of ship (in meters) = 182.9 2) Height of ship (in meters) = 20 (depth) 3) Beam of ship (in meters) = 32.2 (width) 4) Draft (in meters) = 12.18 5) Type of ship Cargo / Container / Oil tanker / Cruise / Chemical Tanker Ship 6) Cargo carrying capacity (in tons) = Not mentioned Real Time Data (at the time of disaster): 1) Date of the disaster: December 15 2) Actual cargo weight at the time of disaster (in tons) = 50033.004 3) Type of cargo the ship was loaded with = Chemicals 4) Weather conditions = heavy seas Reason/s for the disaster (one or more reasons may be present): Reason 1: Improper Loading The ship was carrying trichlorotrifluoroethane and petroleum ether at the time of the disaster. Petroleum ether was loaded in tank numbers 5, 6 and 7. Trichlorotrifluoroethane was loaded in tanks 1, 2 and 3. This means tank number 4 was empty. Total volume of chemical tanks was 52,969 cubic meters, so volume of each tank comes out to be 7567 cubic meters. Total volume of trichlorofluoroethane was 7567*3 = 22701 cubic meters. Density of this chemical is 1564 kg / cubic meter. We can calculate weight by using formula Density = MarineTech Project Ship Disaster Investigation Lean Institute, ODU May 2011
Mass = Density * Volume. So mass of trichlorotrifluoroethane was 35,504,364 kilogram. Using same equation, mass of petroleum ether comes out to be 14,528,640 kilograms. This clearly indicates that there was weight imbalance in the ship. The ship was loaded heavily in the front half. This weight imbalance caused excessive pitching in heavy seas conditions. Excessive stresses were developed in the mid hull section near tank number 4. Reason 2: Single Hull The ship had single hull (mono-hull) design. Tanker ships have double hull design to prevent spillages in case of accidents. But MV Chemstar had a single hull which failed in heavy weather due to excessive stresses. Any other factors (if any) that contributed to the disaster: Any suggestions for improvement a) safety in ship operations and b) ship design and c) ship construction Prepared by: Date: Tanker ships should have double hull design. Special care should be taken during loading 2 or more cargos having different densities. 1) Agent 1 2) Agent 2 3) Agent 3 4) Agent 4 MarineTech Project Ship Disaster Investigation Lean Institute, ODU May 2011
Ship Specifications: Ship Disaster Investigation Report Answer Key Deep Blue Ocean (Case 4) 1) Length of ship (in meters) = Not Mentioned 2) Height of ship (in meters) = Not Mentioned 3) Beam of ship (in meters) = Not Mentioned 4) Draft (in meters) = Not Mentioned 5) Type of ship Submarine 6) Cargo carrying capacity (in tons) = Not mentioned Real Time Data (at the time of disaster): 1) Date of the disaster: January 8, 2005 2) Actual cargo weight at the time of disaster (in tons) = NA 3) Type of cargo the ship was loaded with = NA 4) Weather conditions = Not Mentioned Reason/s for the disaster (one or more reasons may be present): Reason 1: Mistake in the calculation The operating conditions at the time of incidence were reported in the log book. Water temperature 45 0 F Salinity of water 34 parts per thousand SONAR log showed that the time between transmission and reception of signal before an accident was 2 seconds. The navigation officer made a mistake in the distance calculation. Using following formula we calculate the speed of the sound at the depth of 525 feet (operating depth of the submarine) Speed of sound = 4388 + (11.25 temperature (in F)) + (0.0182 depth (in feet) + salinity (in parts-per-thousand)). Speed of sound at 525 meters and at given water conditions is 4959.6 feet per second (1511.61 meters per second) Taking the time between transmission and reception of the SONAR signal into consideration the MarineTech Project Ship Disaster Investigation Lean Institute, ODU May 2011
distance of the seamount from the submarine can be calculated by the following formula. Distance = We have 2 in the denominator because, the time between transmission and reception is the total time taken by sound waves to reach object and come back. Distance of seamount = 1511.61 meters. But the navigation officer calculated the distance wrongly. His answer was double that of the actual distance, which proved fatal. At the time of detection of Seamount Actual distance from Seamount = 1511.61 m (navigation officer calculated 3023 m) Speed of Deep Blue Ocean = 18 m/s At the time of detection of Seamount Actual distance from Seamount = 1511.61-10 x 18 = 1331.61 m (since order for the direction change was given 10 seconds after the detection of Seamount, submarine had traveled 180 meters in the mean time) Deep Blue Ocean required 150 seconds to change its course completely. So in terms of distance it required minimum 150 x 18 = 2700 meters to change its course; but actual distance available was 1331.61 meters only. Serious error in calculation led Deep Blue Ocean to disaster. Any other factors (if any) that contributed to the disaster: Any suggestions for improvement a) safety in ship operations and b) ship design and c) ship construction Prepared by: 1) Agent 1 2) Agent 2 3) Agent 3 4) Agent 4 Date: MarineTech Project Ship Disaster Investigation Lean Institute, ODU May 2011