Teacher’s Manual - Old Dominion Universityaverma/nsf/Marine Kits/Ship... · 2014-05-18 · Keel...

Ship Disaster Investigation

Teacher’s ManualContents

• Teacher’s Instructions

• Check Sheet for

Investigation

• Assessment Sheet

• Agent’s Manual

• Ship Disaster Cases

• Answer Key

Marine Kit – 4

This activity was developed under a grant from the National Shipbuilding Research Program (NSRP)

MarineTech Project Ship Disaster Investigation Lean Institute, ODU May 2011

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)


• 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.

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) =


Group No:

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

Date(mm/dd/yy):

Ship Disaster Investigation Assessment Sheet

This assessment sheet is to be used by the teacher to evaluate

MarineTech Project Ship Disaster Investigation Lean Institute,ODU May 2011

Total Points

the Ship Disaster Investigation Activity

Includes Basic ship Terminologies and Investigation Check list

Sail Smooth, Sail Safe

Marine Kit – 4 Marine Kit – 4

MarineTech Project, Lean Institute ODU, May 2011

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

Index

2MarineTech Project, Lean Institute ODU, May 2011

1. Ship Terminology

Starboard

Port

Stern

Bow

Bow : Front part of the ship

Stern : Rear part of the ship

Starboard : Right side of the ship

Port : Left side of the ship3


Hull

•Most of the modern vessels have

double hull to prevent flooding in

case of accidents.

•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.

Ship Hull

Hull is a body of a ship

Double Hull4


Keel

http://web.nps.navy.mil/~me/tsse/NavArchWeb/1/module2/introductio

n.htm#

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.

Various terms used to define hull cross section

“fore” is the front part

“aft” is the rear part


Cross section of ship

Draft of a ship is the vertical distance between the waterline and the bottom

of the hull

Draft

FreeboardWaterline

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

Beam


Deadrise: Deadrise is an angle measured upward from a horizontal plane at

the keel level.

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

Deadrise


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)

Bulkheads

Bulkheads


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. 9MarineTech Project, Lean Institute ODU, May 2011

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.


http://en.wikipedia.org/wiki/Center_of_gravity

http://en.wikipedia.org/wiki/Volume

http://en.wikipedia.org/wiki/Water

http://en.wikipedia.org/wiki/Hull_%28ship%29

http://en.wikipedia.org/wiki/Displacement_%28fluid%29

http://en.wikipedia.org/wiki/Naval_architecture

http://en.wikipedia.org/wiki/Naval_architecture

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

G

M

B

M

G

B

Stable Unstable11MarineTech Project, Lean Institute ODU, May 2011

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.

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.

What is stable equilibrium?


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.

4. What is the free surface effect?

This effect proves fatal in partially filled ocean going vessels in the

heavy seas.


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.

How to minimize the free surface effect?

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 14MarineTech Project, Lean Institute ODU, May 2011

5. Effect of change in density of water on

the draft of a ship

Density of Fresh Water = 1000 kg / m3

Average Density of Sea Water = 1030 kg / m3

Draft of ship changes with the change in density of water

NewDensity

OldDensity

OldDraft

Draft New

Keeping the load same, change in the draft can be calculated

by following equation

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 aground15


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

6. Displacement of ship

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)


Lightship weight is the

displacement of the ship

only with no fuel,

passengers, cargo, water,

etc. on board.

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

Full Load Displacement:

Displacement when ship is

loaded with cargo or

people to the point that it is

submerged to its load line

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.


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)

cargoofMass

cargoofVolumeStowage Factor =

Proper care should be taken to distribute the load evenly

when carrying high density cargo with stowage factor above

0.56


8. Tanker Ships

Slop tanks are provided for storage of dirty ballast residue and tank

washings from the cargo tanks

General Arrangement of Cargo and Ballast Tanks for Tankers

•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


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

Propellers

Propeller

shaft

Power

Source

(Diesel

Engine /

Steam

Turbine/

Nuclear

power)

Loss of propulsion system can prove fatal, especially in heavy

seas as ship loses control over direction20


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

Propeller shaft

Power Plant

(Engine/ turbine)


• 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


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


24

• 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

• Using the formula Speed = we can calculate the distance of

the object from the source of the pulse (transmitter)Time

ceDistan

SEA BED

Distance “d”

Time “t”


Speed of sound in water is calculated using following equation

4388 + (11.25 × temperature (in °F))

+ (0.0182 × depth (in feet)

+ salinity (in parts-per-thousand)).

Speed of Sound

(feet /s)=

1 foot = 0.3048 meters

Distance from the object is calculated using formula

Distance =Speed of sound x time between transmission and reception

2


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




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




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.


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




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.


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




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: 450

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 Disaster Investigation Report

Write N.A. if data is not given

Ship Specifications:

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:



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


6) Cargo carrying capacity (in tons) = 9500


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 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.




a) safety in ship operations and

b) ship design and


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:



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


6) Cargo carrying capacity (in tons) = 220,966


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 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.





b) ship design and


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:



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


6) Cargo carrying capacity (in tons) = Not mentioned


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 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 =


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.




b) ship design and


Tanker ships should have double hull design.

Special care should be taken during loading 2 or more cargos having

different densities.

Prepared by:

1) Agent 1 _________________________________

2) Agent 2 ________________________________

3) Agent 3 ________________________________

4) Agent 4 ________________________________

Date:



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


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 1: Mistake in the calculation

The operating conditions at the time of incidence were reported in the log book.

Water temperature – 450

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


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.




b) ship design and


Prepared by:

1) Agent 1 _________________________________

2) Agent 2 ________________________________

3) Agent 3 ________________________________

4) Agent 4 ________________________________

Date:

Teacher’s Manual - Old Dominion Universityaverma/nsf/Marine Kits/Ship... · 2014-05-18 · Keel...

Documents

Transcript of Teacher’s Manual - Old Dominion Universityaverma/nsf/Marine Kits/Ship... · 2014-05-18 · Keel...