Marine Courses Center

⚓ OOW ORALS SERIES — LSA SAFETY ⚓
🚨 FPD & Liferaft Container Markings

Two questions that come very often in OOW Orals:

1️⃣ What is the use of FPD?

FPD = Fall Preventer Device

It is used with an on-load release system to prevent the lifeboat from being released unintentionally.

In simple words:

✅ It gives extra safety
✅ It prevents accidental release
✅ It protects the lifeboat crew during drills or launching
✅ It reduces the risk of failure or misuse of the main connection to the fall wire

⚠️ Important Oral Point:
FPD is not the main release system.
It is an additional safety device to prevent accidental lifeboat release.

2️⃣ Markings on a Liferaft Container

Every liferaft container must show important information such as:

✅ Maker’s name
✅ Serial number
✅ Length of painter
✅ Launching instructions
✅ SOLAS marking
✅ Date of last service
✅ Number of persons permitted
✅ Maximum permitted stowage height
✅ Name of approving authority
✅ Type of emergency pack enclosed

🧠 Exam Tip:
When the examiner asks about liferaft markings, don’t just say “SOLAS and capacity.”
Mention service date, painter length, emergency pack type, and approving authority — these details show strong preparation.

🔥 Memory Trick:
“Maker, Serial, Painter, Launch, SOLAS, Service, Persons, Height, Authority, Pack.”

💬 Engagement Question:
Deck Cadets & OOW candidates —
Which one is more commonly missed in oral exams?

A) Length of painter
B) Date of last service
C) Type of emergency pack
D) Approving authority

Write your answer in the comments 👇

⚓ OOW ORALS SERIES — LSA & FFA SAFETY ⚓
🚨 Launching Procedure of an Enclosed Lifeboat

For every OOW, lifeboat launching is not just an exam question — it is a real emergency responsibility.

Before launching, always remember:

✅ Carry out risk assessment
✅ Raise the alarm
✅ Muster crew and take head count
✅ Check PPE and assign duties
✅ Secure painters forward and aft
✅ Check drain plug
✅ Test engine ahead and astern
✅ Check rudder movement
✅ Remove gripes and harbour safety pins
✅ Look overside before lowering
✅ Report to Master: All Clear
✅ Keep vessel speed maximum 5 knots
✅ Lower by gravity
✅ Embark safely by ladder
✅ Ensure all crew are seated and belted
✅ Remove FPD
✅ Start engine and re-check movement
✅ Lower the boat into water
✅ Release hooks and painter
✅ Close hatches and drive away safely

🔥 OOW Oral Tip:
Never answer lifeboat launching as a simple list only. Examiners want to hear safety, communication, control, and sequence.

Your answer must show that you understand:
Risk Assessment → Muster → Preparation → Confirmation → Lowering → Release → Clear the Ship

🧠 Exam Memory Line:
“Assess, Alarm, Muster, Check, Lower, Release, Drive Away.”

Safe launching saves lives.
Wrong sequence can create a second emergency.

🚨 GMDSS EQUIPMENT SERIES 🚨

# SART

# # Search and Rescue Radar Transponder

Imagine abandoning ship in a liferaft during rough weather...

How will rescuers find you on their RADAR?

The answer is:

🟡 SART

One of the most important survival craft locating devices carried onboard.

---

# # 📡 What is a SART?

A Search and Rescue Radar Transponder (SART) is a GMDSS device used to help rescuers locate survival craft using RADAR.

When interrogated by an X-Band RADAR, the SART automatically responds and creates a distinctive pattern on the rescuer's RADAR display.

---

# # 📶 Operating Frequency

SART responds only to:

# # # X-BAND RADAR

📡 Frequency: 9 GHz

📏 Wavelength: 3 cm

---

# # ⚠ Important Oral Exam Question

❓ Will a SART respond to an S-Band RADAR?

# # # Answer:

❌ No

A SART responds only to X-Band RADAR.

---

# # 🔧 How to Activate a SART

1️⃣ Remove SART from bracket.

2️⃣ Lift protective cover.

3️⃣ Turn switch to ON.

4️⃣ Flashing RED light indicates:

✅ SART activated and standing by.

5️⃣ When detected by X-Band RADAR:

🟢 GREEN light flashes

🔊 Audible tone sounds

indicating successful detection.

---

# # 🛰 How Does a SART Appear on RADAR?

# # # More Than 5 NM Away

🔹 12 equally spaced dots (blips)

The last dot represents the SART position.

---

# # # Between 1–5 NM

🔹 12 arcs

pointing towards the SART.

---

# # # Less Than 1 NM

🔹 12 concentric circles

indicating the rescue vessel is very close.

---

# # 📍 Best Position for a SART

Always mount the SART:

# # # AS HIGH AS POSSIBLE

Examples:

🚤 Lifeboat Canopy

⛵ Liferaft Mast

🛟 Elevated Survival Craft Position

Higher antenna height = Greater detection range.

---

# # 🔋 Battery Endurance

# # # Standby Mode

⏳ 96 Hours Minimum

---

# # # Operating Mode

⏳ At Least 8 Hours

after radar interrogation.

---

# # 📋 Monthly Checks

✔ Physical Condition

✔ Battery Expiry Date

✔ Self-Test Function

✔ Mounting Arrangement

✔ External Damage

✔ Correct Installation

---

# # 🎓 Common Oral Exam Questions

❓ What does SART stand for?

❓ What radar responds to a SART?

❓ What frequency does SART operate on?

❓ What appears on radar when SART is more than 5 NM away?

❓ What appears between 1–5 NM?

❓ What appears within 1 NM?

❓ What is the battery endurance of a SART?

---

# # 🧠 Easy Memory Trick

# # # FAR

🔹 12 Dots

---

# # # CLOSER

🔹 12 Arcs

---

# # # VERY CLOSE

🔹 12 Concentric Circles

---

⚓ A SART does not send a distress alert.

📡 It helps rescuers find survivors after a distress situation has already been reported.

🚁 Faster Detection
➕

📡 Clear Radar Target
➕

⚓ Proper Survival Craft Procedures

🟰

🚨 BETTER CHANCE OF RESCUE 🚨

🧠⚓ MARITIME QUIZ SERIES ⚓🧠

Knowledge is one of the most important tools a seafarer can carry on board.

Our Maritime Quiz Series is designed to help maritime students, deck cadets, and future officers strengthen their understanding of navigation, COLREGs, seamanship, cargo operations, meteorology, and shipboard safety.

Every quiz is an opportunity to learn, improve, and prepare for your maritime career.

📚 Learn More.
⚓ Train Smarter.
🚢 Sail Safer.

Follow Marine Courses Center for more maritime quizzes, interview preparation, and professional maritime training content.

🚨 GMDSS EQUIPMENT SERIES 🚨

EPIRB
Emergency Position Indicating Radio Beacon

Imagine your vessel is sinking and all communications are lost...

How will Search and Rescue authorities know your position?

The answer is:

🟡 EPIRB

One of the most important life-saving devices carried onboard.

📡 What is an EPIRB?

An EPIRB is a distress alerting beacon designed to automatically notify Search and Rescue (SAR) authorities when a vessel is in grave and imminent danger.

It forms a vital part of the GMDSS system.

📶 EPIRB Frequencies
406 MHz

Used for:

✅ Distress Alert Transmission

✅ COSPAS-SARSAT Satellite System

The transmitted message may include:

✔ Beacon ID

✔ MMSI

✔ Vessel Identification

✔ GPS Position (if fitted)

✔ Country Code

121.5 MHz

Used for:

🚁 Homing Signal

Allows rescue aircraft and rescue vessels to locate the beacon during the final stage of a rescue operation.

⚙️ How Does EPIRB Activate?
Manual Activation

The crew manually switches ON the EPIRB.

Automatic Activation

When the vessel sinks:

🌊 Water pressure activates the HRU

🔓 HRU releases the EPIRB

🟡 EPIRB floats free

📡 Distress transmission begins automatically

🌊 Hydrostatic Release Unit (HRU)

The HRU automatically releases the EPIRB when submerged.

📏 Release Depth:

1.5 – 4 metres

below the water surface.

🚨 Distress Alert Chain

EPIRB

⬇

COSPAS-SARSAT Satellite

⬇

Mission Control Centre (MCC)

⬇

Rescue Coordination Centre (RCC)

⬇

Search and Rescue Units

🚁 🚢

📋 Monthly EPIRB Checks

✔ Physical Condition

✔ Battery Expiry Date

✔ HRU Expiry Date

✔ Mounting Bracket

✔ Self-Test Function

✔ External Damage

✔ Correct Installation

🎓 Common Oral Exam Questions

❓ What does EPIRB stand for?

❓ What frequency does EPIRB transmit on?

❓ What is the homing frequency?

❓ How is EPIRB activated?

❓ At what depth does the HRU release the EPIRB?

❓ Who receives the distress alert?

🧠 Cadet Memory Trick
EPIRB

E ➜ Emergency

P ➜ Position

I ➜ Indicating

R ➜ Radio

B ➜ Beacon

Remember:

📡 406 MHz = Distress Alert

🚁 121.5 MHz = Homing Signal

⚓ EPIRB doesn't save the ship...

🚁 It saves the people on it.

🚢 NAVIGATIONAL EQUIPMENTS ON BOARD 🚢

🔊 ECHO SOUNDER

One of the most important navigational instruments used on board to determine the depth of water beneath the ship and ensure safe navigation in coastal waters, channels, and restricted areas.

📖 What is an Echo Sounder?

An Echo Sounder measures the depth of water beneath a vessel by:

📡 Transmitting a sound pulse

🌊 Receiving the echo reflected from the seabed

⏱ Measuring the time taken for the echo to return

The depth is then automatically calculated and displayed.

⚙️ Main Components

🔹 Transducer

🔹 Pulse Generator

🔹 Amplifier

🔹 Recorder / Display Unit

🎛 Common Controls

✔ Range Selector

✔ Gain Control

✔ Unit Selector (m / ft / fathoms)

✔ Draft / Keel Offset Adjustment

✔ Transducer Changeover

⚠️ Limitations of Echo Sounder

❌ Shallow Water Effects

❌ Different Water Layers (Thermocline)

❌ Pythagoras Error

❌ Electrical Noise

❌ Mechanical Noise

❌ Biological Noise (Fish & Plankton)

❌ Wrong Range Selection

❌ Sound Velocity Errors

❌ Cavitation (Propeller Bubbles)

❌ Air Bubbles Around Transducer

❌ Sloping Seabed

❌ Soft Mud Bottom

🌡 Factors Affecting Speed of Sound in Water
Temperature

Higher Temperature ➜ Higher Sound Speed

Salinity

Higher Salinity ➜ Higher Sound Speed

Pressure (Depth)

Greater Depth ➜ Higher Sound Speed

🎓 Common Oral Exam Question

❓ What factors affect the speed of sound in water?

✅ Temperature

✅ Salinity

✅ Pressure (Depth)

🧠 Cadet Memory Trick
TSP

🌡 Temperature

🧂 Salinity

🌊 Pressure

These are the three main factors affecting sound velocity in water.

📐 Echo Sounder Formula

Depth = (Speed of Sound × Time) ÷ 2

The division by 2 is because the sound pulse travels:

⬇️ To the seabed

⬆️ Back to the transducer

⚓ Important Reminder

Always cross-check Echo Sounder readings with:

✔ Nautical Charts

✔ Tide Information

✔ UKC Calculations

✔ Other Navigational Aids

Never rely on a single instrument for safe navigation.

🚢 Accurate Depth Information
➕

⚓ Proper Interpretation
➕

🗺 Good Seamanship

🟰

🌊 SAFE NAVIGATION

🚢 GMDSS DAILY CHECKS & SEA AREAS 🚢

📡 Global Maritime Distress and Safety System (GMDSS)

Every Officer of the Watch must be familiar with GMDSS equipment checks and the different GMDSS Sea Areas. Regular testing ensures that distress alerts can be transmitted and received when lives depend on it.

✅ DAILY CHECKS

🔹 VHF DSC Internal Test

🔹 Emergency Battery Status

🔹 Printer Paper & Ink Check

🔹 UTC Clock Verification

🔹 Radio Log Properly Maintained

✅ WEEKLY CHECKS

🔹 MF DSC Test on 2187.5 kHz

🔹 VHF Operational Test

🔹 Verify Transmitter & Receiver Performance

✅ MONTHLY CHECKS

🔹 Antenna Inspection

🔹 EPIRB Inspection & Self-Test

🔹 SART Inspection & Self-Test

🔹 Emergency Battery Check

🔹 NAVTEX Operational Check

🔹 Inmarsat-C Operational Check

🌍 GMDSS SEA AREAS
🟢 Sea Area A1

Within VHF DSC coverage of a coast station.

📡 Distress Watch:

Channel 70

🟡 Sea Area A2

Outside A1 but within MF DSC coverage.

📡 Distress Watch:

2187.5 kHz

🔵 Sea Area A3

Outside A1 & A2 but within Inmarsat coverage.

Coverage:

Approximately 70°N to 70°S

📡 Distress Watch:

HF DSC

4, 6, 8, 12 & 16 MHz Bands

and/or Inmarsat Services

⚪ Sea Area A4

Polar Regions

Outside A1, A2 and A3

📡 Distress Watch:

HF DSC

4, 6, 8, 12 & 16 MHz Bands

(No Inmarsat Coverage)

🎯 Most Common Oral Exam Questions

❓ What are the four GMDSS Sea Areas?

❓ What is the MF DSC distress frequency?

❓ What channel is used for VHF DSC distress alerts?

❓ What monthly checks are carried out on an EPIRB?

❓ What is checked during a SART inspection?

🧠 Easy Memory Trick
DAILY

📡 DSC

🔋 Battery

🖨 Printer

🕒 Clocks

📖 Radio Log

WEEKLY

📡 MF Test

📻 VHF Test

MONTHLY

📡 Antenna

🚨 EPIRB

📡 SART

🔋 Batteries

📰 NAVTEX

🛰 Inmarsat-C

⚓ Communication failures can cost lives.

Check your equipment.

Know your Sea Area.

Be ready before the emergency happens.

🚢 NAVIGATIONAL EQUIPMENTS ON BOARD 🚢

📡 AIS (Automatic Identification System)

AIS is one of the most important bridge systems for situational awareness, traffic monitoring, and collision avoidance. It automatically exchanges vessel information with nearby ships and shore stations using VHF radio communication.

📋 Information Provided by AIS
1️⃣ Static Information

✔ MMSI

✔ IMO Number (where available)

✔ Call Sign

✔ Ship Name

✔ Length and Beam

✔ Ship Type

✔ Position of GNSS Antenna

2️⃣ Dynamic Information

✔ Ship Position

✔ Position Accuracy

✔ UTC Time Stamp

✔ Course Over Ground (COG)

✔ Speed Over Ground (SOG)

✔ Heading

✔ Navigational Status

✔ Rate of Turn (if available)

3️⃣ Voyage Related Information

✔ Ship's Draft

✔ Hazardous Cargo Information

✔ Destination

✔ ETA

4️⃣ Safety Related Messages

✔ Free-format safety messages

✔ Short Safety-Related Messages (SRM)

⚠️ Limitations of AIS

❌ Information may be outdated.

❌ Incorrect manual inputs may be entered.

❌ CPA/TCPA is based on COG and SOG.

❌ Sensor failures affect AIS data.

❌ Antenna offsets may be set incorrectly.

❌ Not all vessels carry AIS.

❌ Coding and decoding incompatibilities may occur.

❌ Human error remains a major limitation.

⚖️ AIS Carriage Requirements (SOLAS)

AIS is mandatory for:

🚢 All Passenger Ships

🚢 Cargo Ships ≥ 300 GT on International Voyages

🚢 Cargo Ships ≥ 500 GT not engaged on International Voyages

🛡 Master's Authority

The Master may switch off or restrict AIS transmission if the security of the ship is threatened, such as:

⚠ Piracy Risk

⚠ Armed Robbery Risk

⚠ Security Threats

🎯 Important Reminder

AIS is an AID to navigation.

It is NOT a substitute for:

👀 Proper Lookout

📡 RADAR

🗺 ECDIS

⚓ Good Seamanship

Always cross-check AIS information with other navigational aids.

🧠 Cadet Memory Trick
AIS Information

🔹 Static → Who the ship is

🔹 Dynamic → Where the ship is now

🔹 Voyage → Where the ship is going

🔹 Safety → Messages and warnings

⚓ Good AIS Interpretation
➕

📡 RADAR Cross-Checking
➕

👀 Effective Lookout

🟰

🚢 SAFE NAVIGATION

🚢 NAVIGATIONAL EQUIPMENTS ON BOARD 🚢

📡 RADAR (Radio Detection And Ranging)

PART 3 – ERRORS, LIMITATIONS & PERFORMANCE MONITORING

A RADAR is only as good as the navigator's understanding of its limitations. Knowing RADAR errors can prevent misinterpretation and improve collision avoidance decisions.

⚠️ Common RADAR Errors & Limitations
1️⃣ Side Lobe Error

Strong targets may produce:

❌ False echoes

❌ Multiple echoes

appearing on either side of the true target.

2️⃣ Minimum Range Limitation

Very close targets may not be detected because of:

Pulse length
Antenna height
Vertical beam width
Receiver recovery time

This creates a blind area around own ship.

3️⃣ Blind / Shadow Sector

Targets may not be detected behind:

⚓ Funnel

⚓ Mast

⚓ Crane

⚓ Superstructure

4️⃣ Range Discrimination

Two targets:

📍 Same Bearing

📍 Different Ranges

➡ RADAR may display them as one target.

5️⃣ Bearing Discrimination

Two targets:

📍 Same Range

📍 Different Bearings

➡ RADAR may display them as one target.

6️⃣ Target Swap

When targets are close together:

🔄 ARPA target information may interchange.

Tracks and data may be assigned incorrectly.

7️⃣ Multipath Error

RADAR signals may reflect from:

🏗 Cranes

🏗 Large Structures

🏗 Superstructure

Creating false echoes.

8️⃣ Second Trace Echo

A distant target may appear:

❌ Closer than its actual position.

Always verify suspicious contacts.

🔍 How To Check RADAR Performance?

Use the Performance Monitor function.

Procedure:

1️⃣ Press the Performance Monitor button.

2️⃣ Select 12 NM range scale.

3️⃣ Allow the RADAR to run the test.

4️⃣ Check:

✅ Magnetron Condition

✅ Transmitter Performance

✅ Receiver Performance

5️⃣ Compare results with manufacturer's limits.

📡 Why Is Performance Monitoring Important?

Because it verifies that:

✔ Transmitter is operating correctly

✔ Receiver sensitivity is acceptable

✔ Magnetron performance is satisfactory

✔ RADAR picture can be trusted

🎓 Common Oral Exam Questions

❓ Difference between X-Band and S-Band?

❓ Sea Stabilized vs Ground Stabilized?

❓ Short Pulse vs Long Pulse?

❓ Name common RADAR errors.

❓ How do you check RADAR performance?

🧠 Memory Trick
RADAR ERRORS

S M B R B T M S

🔹 Side Lobe

🔹 Minimum Range

🔹 Blind Sector

🔹 Range Discrimination

🔹 Bearing Discrimination

🔹 Target Swap

🔹 Multipath Error

🔹 Second Trace Echo

⚓ Remember:

A RADAR never replaces a proper lookout.

Always cross-check RADAR information with:

👀 Visual Observations

📡 AIS

🗺 ECDIS

⚓ Other Navigational Aids

🚢 Good RADAR Setup
➕

🎯 Correct Interpretation

🟰

⚓ SAFE NAVIGATION ⚓

🚢 NAVIGATIONAL EQUIPMENTS ON BOARD 🚢

📡 RADAR (Radio Detection And Ranging)

PART 2 – MODES & APPLICATIONS

Understanding RADAR modes and settings is essential for every Deck Cadet and Officer of the Watch.

📡 X-BAND vs S-BAND
X-BAND

📏 Wavelength: 3 cm
📡 Frequency: 9 GHz

Best for:

❄ Ice Navigation

🚨 Search & Rescue (SAR)

⚓ Coastal Navigation

🎯 Detecting Small Targets

🔍 Better Target Definition

S-BAND

📏 Wavelength: 10 cm
📡 Frequency: 3 GHz

Best for:

🌧 Heavy Rain

🌊 Adverse Weather

🎯 Long-Range Detection

💡 Less affected by rain clutter

🌊 Sea Stabilized vs 🌍 Ground Stabilized
Sea Stabilized

⚓ Connected to Ship's Log

📈 Provides Speed Through Water (STW)

🌊 Motion referenced to water

Ground Stabilized

📡 Connected to Doppler Log or GPS

📈 Provides Speed Over Ground (SOG)

🌍 Motion referenced to earth

📶 Short Pulse vs Long Pulse
Short Pulse

✅ Better target separation

✅ Better close-range detection

✅ Harbour Navigation

✅ Coastal Navigation

✅ Dense Traffic Areas

Long Pulse

✅ Better long-range detection

✅ Greater transmitted energy

✅ Better pe*******on through rain

✅ Open Sea Navigation

🖥 Common RADAR Display Modes
Head Up (HU)

🧭 Ship's heading always at the top of the display.

Most intuitive for watchkeeping.

North Up (NU)

🧭 True North always at the top.

Preferred for navigation and chart comparison.

🚢 Motion Modes
Relative Motion (RM)

Own ship remains fixed.

Targets move relative to own ship.

True Motion (TM)

All targets move according to their true course and speed.

Useful for overall traffic assessment.

🛠 Useful RADAR Tools

📍 EBL (Electronic Bearing Line)

Used to measure bearing of a target.

⭕ VRM (Variable Range Marker)

Used to measure range of a target.

📈 Trails

Show previous target positions.

➡ Vectors

Show predicted target movement.

🧠 Cadet Memory Tricks

X-BAND

❄ Ice

🚨 SAR

⚓ Coastal

🎯 Small Targets

S-BAND

🌧 Storms

🌊 Heavy Rain

Sea Stabilized

⚓ Log → STW

Ground Stabilized

📡 GPS/Doppler → SOG

⚓ Good RADAR setup + Correct interpretation = Safe Navigation