Daily, Monthly And Weekly Tests Of GMDSS Equipment On Board Ships

 development of GMDSS (Global Maritime Distress And Safety System) for the shipping industry has come a long way. The GMDSS system was established with an objective to improve distress and safety radio communications and procedures at sea.

The greatest benefit of the GMDSS equipment is that it vastly reduces the chances of ships disappearing without a trace, and enables search and rescue (SAR) operations to be launched without delay and directed to the exact site of a maritime disaster.

Gone are the days when ships were required to have dedicated radio officers to operate radio equipment. With the implementation of GMDSS every deck officer with a General Operator Certificate (GOC) and license is entitled to use the GMDSS equipment and make radio communications when needed.

For the GMDSS equipment to function properly and effectively in the event of an emergency, it is critical that mariners understand its purpose and do the required maintenance on board the vessel to keep it in a working condition and make the best use of GMDSS equipment.

The daily, weekly and monthly tests of all the GMDSS equipment should be done by every navigating officer responsible for it without any compromise. We must not forget that it is our only best friend in a distress situation at sea.

Ships at sea must be capable of performing the nine functional GMDSS requirements. They are:

1. Ship-to-shore distress alerting
2. Shore-to-ship distress alerting
3. Ship-to-ship distress alerting
4. SAR coordination
5. On-scene communications
6. Transmission and receipt of emergency locating signals
7. Transmission and receipt of MSI
8. General radio communications
9. Bridge-to-bridge communications

This can be ensured by testing the GMDSS equipment at regular intervals.

The GMDSS equipment and systems include the VHF DSC/RT, MF/HF DSC/RT, INMARSAT, SART, EPIRB, NAVTEX, and SURVIVAL CRAFT TWO WAY VHF.

Daily Tests On GMDSS Equipment

The proper functioning of the Digital Selective Calling (DSC) facilities shall be tested at least once each day, without radiation of signals, by the use of the equipment’s Internal test facility. The daily test checks the internal connection, transmitting output power and the display. The process can differ from equipment to equipment based on the make.

The daily test of the FURUNO model of the VHF equipment can be executed as below:

1.At the standby display press the SHIFT key followed by the TEST key. The “TEST IN PROGRESS” pop up window appears momentarily and distress alarm both visual and audible occurs.

The display shows the TEST screen. If everything is okay with the set and is functioning properly, the results show OK as below. However, in some situation or if it’s a faulty equipment, ‘NG’ may be displayed. In this case the daily test should be repeated a couple of times. If the problem persists, it should be immediately brought to the notice of a shore based service engineer.

2. Press the CANCEL key to stop the alarm. To stop the daily test, press the CANCEL key again.

Daily test also needs to be performed on the MF/HF equipment to ensure it will function properly in the event of distress.

1.  Press the [3/TEST] key to start the test. Select the Daily Test by rotating the knob and push to enter. After several seconds the display shows the test results; OK for normal operation. The audio alarm also sounds after the test results are displayed and the alarm lamp flashes several times.

2. The CANCEL key should be pressed to quit the test and return to the normal screen.

Batteries providing reserve source of energy should also be checked daily. Mainly the battery ON LOAD and OFF LOAD voltages are checked by a volt meter connected to the charger.

OFF LOAD: when no equipment are connected, the battery should read 24 V or slightly more.

ON LOAD: switch off the AC power and note the voltage of the battery. Press the PTT on MF/HF transceiver on a non-distress and idle R/T frequency. Voltage will fall depending upon the load. If the voltage falls more than 10% it indicates that the battery is either weak or not charged fully. In this case batteries should be recharged.

It is also important to check that all printers are in a working condition and there is sufficient supply of paper.

Weekly Tests On GMDSS Equipment

It is necessary to test the proper operation of the DSC facilities at least once a week by means of a test call over one of the six distress and safety frequencies, when within the communication range of a coast station fitted with a DSC equipment. A test call to the coast station can be sent in the following ways:

MF/HF DSC:

1.  Press the [2/DSC] key at the DSC standby screen and then push the [ENTER] knob to open the CALL TYPE menu.

2. Rotate the [ENTER] knob to choose TEST CALL and then push the [ENTER] knob. Push the [ENTER] knob again to open the COAST ID menu.

3. Using the numeric keys, key in the ID of the coast station ID (seven digits) where you want to send the call depending upon the area you are navigating in and then push the [ENTER] knob. The coast station ID can be found from the Admiralty List of Radio Signals Volume 1- Maritime Radio Stations.

4.Now push the [ENTER] knob to open the DSC FREQ menu. (Note that here the PRIORITY is automatically selected to SAFETY.)

5. Rotate the [ENTER] knob to choose an appropriate frequency and then push the [ENTER] knob.

6.Now press the [CALL] key to send the TEST call to the respective shore station.

After the test call has been sent successfully the acknowledgement is received from the shore station. The audio alarm sounds on receiving the acknowledgement.

Many a times it often happens that the officer do not receive any acknowledgment from the shore station. In such cases we often take it for granted that the shore station is not sending the acknowledgement. However, in reality this might not be the case. The problem could be with our equipment too. To make sure that the MF/HF equipment is in order, it is better we try sending the test call using other frequencies and to other stations. Even if then we fail to receive any acknowledgement, a test call can be sent to a passing ship if possible. Instead of keying the coast ID, key in the MMSI of the passing ship. It is better to call the ship and confirm if they have received the test call. We can also request them to send us a test call to ensure that the equipment receiving facility is functioning properly.

It is also recommended that a station to station test takes place using VHF DSC.

1. Press the CALL key. This will open the compose message screen where the call type can be selected. Rotate the channel knob to select TEST call.

2.Enter the Station ID, in this case the MMSI of your own ship and then press the CALL key for it to be transmitted.

The audio and visual alarm is generated and test call is received on the other VHF station. Press cancel to terminate the test call.

Monthly Tests On GMDSS Equipment

EPIRB: The Emergency Position Indicating Radio Beacon should be examined by carrying out a self test function without using the satellite system. No emergency signal is transmitted during the self test. During the self test the battery voltage, output power and frequency is checked. The EPIRB should also be checked for any physical damage. The expiry date of the battery unit and that of the hydrostatic release unit should be checked. Also check that the safety clip is properly attached and in place.

To perform the self test on the JOTRON EPIRB:

1. The EPIRB should be removed from the bracket first.

2. The spring loaded switch on top of the EPIRB is then lifted to the TEST position.

A successful test will consist of a series of blinks on the LED test-indicator, followed by a continuous light and a strobe flash after approximately 15 seconds. The last green led indicates a successful test.

3. After the successful completion of the test the switch is released and the EPIRB is put back into the bracket.

SART: The Search and Rescue Transponder is also equipped with a self test mechanism to test the operational function of the beacon. The SART is tested using the ship’s X band radar. The test should preferably be done in open seas to avoid interference on the radar display.

1. Remove the SART from the mounting bracket.
2. The SART should be held by one person in view of the radar scanner. This could be done from the bridge wings. The SART should then be put on the TEST mode by rotating it to the left to the TESTPREVUE position for a brief period.

Visual lights operate and bleeps are heard indicating that the SART has been triggered.

3. Simultaneously a person should observe the radar display for the correct pattern. At least 11 concentric circles appear on the radar display if kept on a 12 M range scale. The distance between two rings is approximately 0.64 NM.

4. The SART should also be visually inspected for any signs of physical damage. The battery expiry date should also be noted. The safety clip should be in place.

SURVIVAL CRAFT TWO WAY PORTABLE VHF EQUIPMENT

Each survival craft two way VHF equipment should be tested at least once a month to ensure proper operation in case of a distress situation. It should be tested on a frequency other than vhf channel 16 (156.8 MHz). The expiry date of the battery needs to be checked and changed when required.

1.  Press the power key to switch on or off.

2.  To select a different channel, press the CH key and use the arrow keys to select the required channel. The selected channel is indicated with channel number and frequency on the screen.

3.  Press the PTT (Push to talk) to communicate with another radio telephone to test receive and transmit functions. One person can stand near the VHF receiver to receive a test call from the handheld radio.

The symbol ‘TX’ is shown when the PTT is pressed and transmission takes place. The TX indicator indicates that carrier is produced at the antenna output.

When it receives a signal the symbol ‘RX’ is indicated on the display.

NAVTEX :

The Navtex is an equally important GMDSS equipment and is the source of maritime safety information. It is also equipped with a test function that can test the battery, keyboard, LCD, ROM and RAM. It is a good practice to test the Navtex and detect error if any. The Furuno model of Navtex can be tested as follows:

1. Press the MENU/ESC key to open the main menu.

2. Now use the navigating arrows to choose SERVICE and then hit ENT. The SERVICE sub menu contains the TEST option. Use the down arrow key to select TEST and press ENT key. Choose YES and press the ENT key again. The TEST will start and the results will be displayed on the screen after few seconds.

If the test is successful the results show OK otherwise it will show NG meaning – No Good.

It also tests each key for proper functioning.

The Rx test screen shows as follows:

The test results can be printed and filed in the GMDSS log book.

INMARSAT: The INMARSAT is also equipped with a diagnostic test which checks it for proper operation. The steps to perform a Diagnostic Test on FURUNO INMARSAT are given below;

1. On the keyboard press the F7 key to display the ‘OPTIONS’ menu.
2. Use the down arrow to open the TEST menu and then select the DIAGNOSTIC TEST. Select YES to begin the test.

On completion of the test, the results are shown on the screen as below. The ESC key is used to return to the main menu.

A PV test or Performance Verification test can be performed every month. This test consists of receiving a test message from an LES (Local Earth Station), transmitting a message to an LES and a distress alert test. The PV TEST can be opened from the TEST menu under OPTIONS as mentioned above.

The status shows ‘TESTING’ when the test is in process.

The status changes to IDLE on completion of the PV Test.

The test results can be seen from the option ‘PV Test Result’ under the TEST menu. The test results can be printed and logged. BBER denotes the bulletin board error rate. Pass appears for no error. “PASS” appears for satisfactory completion of the test.

BATTERY: The battery connections and compartment should also be checked. The level of the electrolyte and the specific gravity of each cell should be checked and recorded. Sulfation can reduce the specific gravity thereby reducing the battery capacity. Maintenance free batteries on board however do not require any such checks.

It is recommended every month to visually check all antennas for security of mounting and visible damage to the cables. The antennas are located on the monkey island. Any deposit of dirt and salt should be removed. It is also important to check the condition of the aerials and insulators along with the help of an electrical officer. Ensure that the equipment is switched off and isolated before carrying out any work on the antenna.

GMDSS enables a ship in distress to send an alert using various radio systems. It is therefore important that all the GMDSS equipment are maintained in a state of readiness and working condition. To achieve this it is mandatory to perform the daily, weekly and monthly tests. Only then can we ensure the safety of the ship and its crew.

Different Types of alarms on Ships

An emergency does not come with an alarm but an alarm can definitely help us to tackle an emergency or to avoid an emergency situation efficiently and in the right way. Alarm systems are installed all over the ship’s systems and machinery to notify the crew on board about the dangerous situation that can arise on the ship.

Alarm on board ships are audible as well as visual to ensure that a person can at least listen to the audible alarm when working in a area where seeing a visual alarm is not possible and vice versa.

It is a normal practice in the international maritime industry to have alarm signal for a particular warning similar in all the ships, no matter in which seas they are sailing or to which company they belongs to. This commonness clearly helps the seafarer to know and understand the type of warning or emergency well and help to tackle the situation faster.

The main alarms that are installed in the ship to give audio-visual warnings are as follows:

1) General Alarm: The general alarm on the ship is recognized by 7 short ringing of bell followed by a long ring or 7 short blasts on the ship’s horn followed by one long blast. The general alarm is sounded to make aware the crew on board that an emergency has occurred.

Credits: Todd Lappin/flikr.com

2) Fire Alarm: A fire alarm is sounded as continuous ringing of ship’s electrical bell or continuous sounding of ship’s horn.

3) Man Overboard Alarm: When a man falls overboard, the ship internal alarm bell sounds 3 long rings and ship whistle will blow 3 long blasts to notify the crew on board and the other ships in nearby vicinity.

4) Navigational Alarm: In the navigation bridge, most of the navigational equipments and navigation lights are fitted with failure alarm. If any of these malfunctions, an alarm will be sounded in an alarm panel displaying which system is malfunctioning.

5) Machinery space Alarm: The machinery in the engine room has various safety devices and alarms fitted for safe operation. If any one of these malfunctions, a common engine room alarm is operated and the problem can be seen in the engine control room control panel which will display the alarm.

6) Machinery Space CO2 Alarm: The machinery space is fitted with CO2 fixed with fire extinguishing system whose audible and visual alarm is entirely different from machinery space alarm and other alarm for easy reorganization.

7) Cargo Space CO2 Alarm: The cargo spaces of the ship are also fitted with fixed fire fighting system which has a different alarm when operated.

8) Abandon Ship Alarm: When the emergency situation on board ship goes out of hands and ship is no longer safe for crew on board ship. The master of the ship can give a verbal Abandon ship order, but this alarm is never given in ship’s bell or whistle. The general alarm is sounded and every body comes to the emergency muster station where the master or his substitute (chief Officer) gives a verbal order to abandon ship.

9) Ship Security Alarm System: Most of the ocean going vessels are fitted with security alert alarm system, which is a silent alarm system sounded in a pirate attack emergency. This signal is connected with different coastal authorities all over the world via a global satellite system to inform about the piracy.

Different Alarm signals of the vessel are clearly described in the muster listalong with the action to be carried out so that all the crew member can perform there duties within no time in actual emergency.

#Ship Squad Formula

Ship Squqt formula

Find the approximate calculated squat of your vessel is proceeding to a channel #not enclosed with a width of 90 meters deep and dredge surrounding depths of 20 meters. Your vessel's draft is 11 meters and beam of 27 meters, speed 7 knots and block coefficient is 0.8 

Given:

Speed = 7 knots

Block Coefficient = 0.8

What is asked?

Ship's squat

Solution:

This is the ship's squat formula on open waters and the unit of the answer will be meter.

  Squat = Block Coefficient x Speed² /100

                                 = (0.8 x 7²)/100

                                 = (0.8 x 49)/100

                                 = 39.2 / 100

                       #Squat = 0.392 m      

Again, the example above is that we get  the value of the ship's squat in open waters. You might asked then, if there's a formula for squat on open waters, what will be the formula for squat on #enclosed water?

To get the value of squat on enclosed water is to multiply block coefficient by the square of speed, and then times 2, then divide the product by 100.

Here is the problem for squat on closed water. 

A container vessel of 12,000 tons displacement is approaching her berth at speed of 4 knots. Its block coefficient is 0.78. Calculate the value of squat.

Answer: 0.25 meters

  Squat = (Block Coefficient x Speed²)×2 /100

                                 = (0.78 x 4²) × 2 /100

                                 = (0.78 x 16) × 2 /100

                                 = 24.96 / 100

                       #Squat = 0.25 m  

#Draft_Survey_Procedures_and_Calculation ...

#Draft_Survey_Procedures_and_Calculation ...           

The Draft Survey procedures and calculation ascertained as the following series :

01. Reading the draftmark of the ship, which consist of six (6) points of draftmarks, i.e.; Fore, Midship, and After at both sides of the ship,

02. Sampling and testing the sea water or dock water density at the place where the vessel floats,

03. Determining of deductible weights by measuring and sounding of ballast tanks, fuel oil, fresh water that existing onboard at the time of survey,

04. Using Hydrostatic Table provided onboard to calculation.

#Reading_the_Draftmark_of_the_ship 👇

Commonly, all ship are designed with draftmark for working with Draft Survey to determined their actual weight. 

The draftmark could be find at six (6) points on the below places:

●Forward Port Side (FP),

●Forward Starboard Side (FS),

●Midship Port Side (MP),

●Midship Starboard Side (MS),

●Aftward Port Side (AP),

●Aftward Starboard Side (AS),

Use the small boat to go around the ship and get as near as possible to the draft mark for best viewing. The surveyor should be read all above marks clearly, because reading the draftmark is the first and most essential process. I am not saying that other processses is not essensial, but this process is hard to do and involves many rules of conduct to gain the correctness and accuracy of Draft Survey itself (I will post it later). The draftmark read is recorded on the surveyor notebook, do not try to remember it or write down in your palm hand. Its useless and un-professional.

#Sampling_and_testing_the_sea_water_or_dock_water_density 👇

After reading the draftmark, directly engage with the sampling of sea water or river water around the ship’s dock.  Why? 

Because the ship draft will not be the same at different water densities (at the lower density means the ship more sink and at the higher density means the ship more float).  

Where as the water density is subject to changes which follow with water tide that carrying different water salinity and temperature on to the ship dock. 

The sea water density is indeed at density 1.025 and the fresh water at density 1.000. 

To determine the density of water, we need the instrument named Hydrometer or Density Meter. Inserted the Hygrometer on to the water sample on the Sampling Can or Tube, then we could check the scale pointed on the surface of the sampling water. Records the water dock density as survey data.

#Determining_of_deductible_weights_by_measuring_and_sounding 👇

Deductible Weight could measure by sounding  the tanks which used the Sounding Tape or gauging the tank level by visual inspection. 

Any deductible weight such as Ballast Water, Fresh Water, Fuel and Diesel Oil, and Bilges is notify to check. 

Records all in the survey book includes with the density for Ballast and Bilges, and for Oil complete it with density and temperature . The Fresh Water was at density 1.000.

#Using_Hydrostatic_Table_provided_onboard_to_begin_calculation 👇

I think all necessary data was completed, so we could do calculation. 

The calculation is uses Displacement Table or usually called Hydrostatic Table. This table is included all data that we need to complete the calculation.

●Raw Draft Calculation; 

Fore Mean or Fm = (FP+FS)/2, 

Mid Mean or Mm = (MP+MS)/2, and Fore Mean or Am = (AP+AS)/2. 

while Apparent Trim  or AT = Am – Fm. 

the Apparent Trim is the Trim that visually find.

●Draftmark posision and correction to perpendicular. 

As the ship draftmark is not placed at the perpendicular, the Fore and After draft should be corrected with distance from the draftmark to perpendicular. 

The correction rules is: if the Trim by Stern, the Fore correction should be minus and After correction plus, and if the Trim by Head (stem), the Fore correction should be plus and After correction minus. 

The Midship correction is parallel with the fore correction with the same pattern. 

Some Hydrostatic table provided with these correction result. 

But if not the reference pattern is  for 

Fore Correction or Fc = (Fd x AT) : LBM and After Correction or Ac = (Ad x AT) / LBM. Where Fd = Fore distance to perpendicular, 

Ad = After distance to perpendicular, and LBM = Length Between Mark or Length between Fore and After draftmarks  or 

LBM = LBP – (Fd + Ad).

●True Draft Calculation / Draft Corrected; 

Fore draft corrected or Fcd = Fm + Fc, 

Mid draft corrected or Mcd = Mm + Mc, 

and After draft corrected or Acd = Am + Ac.

●True Trim or TT : Actual  Ship Trim after draft corrected or  TT = Acd – Fcd.

●Fore and After Mean Draft or FAm = (Fcd + Acd)/2, Mean of Mean Draft or MM = (FAm + Mcd)/2, and Mean of Mean of Mean Draft  or MMM or Quarter Mean = (MM + Mcd)/2.

●The above calculation is similar with : 

MMM = {(Fcd x 1) + (Acd x 1) + (Mcd x 6)}/8.

●Coresponding to the MMM or Quarter Mean result, the surveyor could check the value of needed parameters on Hysdrostatic table like; Displacement, TPC, LCF, and MTC. Records them accurately.

●Get the Displacement or Disp.

●First Trim Correction or 

FTc = (TT x LCF x TPC x 100) / LBP. 

Could be plus or minus depend on LCF.

●Second Trim Correction 

STc = (TT x TT x MTC x 50) / LBP. 

The result always plus (+).

●Displacement corrected by Trim or 

DispT = D – (FTc + STc).

●Density Correction or 

Denc = DispT x {(Aden – 1.025) / 1.025}. 

where the Aden is Actual Density that surveyor has taken sampling and testing previously. 

The density correction commonly in minus (-), due to the Actual Density is usually lower than 1.025 (fresh sea water). 

In case of at some port where the water salinity is high, the density correction could be plus (+).

●And we have got the Displacement corrected by Density or 

DispDenc = DispT + Denc. (after corrected by density we will get the actual ship weight as per shown by Draft Survey)

●Deductible Calculation. The same as draft, the deductible also need to corresponding to the table that named Tank Table / Tank Capacity Table. 

Refer to the sounding records that done before, the surveyor could be calculate the total deductbile existing onboard. 

Total Deductible or Deduct =  Ballast Water + Fresh Water + Bilges + Fuel Oil + Diesel Oil,  this total should be minus to the Displacement corected by Density.

●The Net Displacement or 

NDisp = DispDenc – Deduct.

●The Net Displacement is the actual ship weight after minus with deductible weight. For Unloading, to estimate the quantity of cargo onboard, the Net displacement should be minus with Light Ship and Constant.👌

#Ship Captain

The_Captain  

The captain studies chemistry, physics, mathematics, engineering, medicine, and ample medicine if anyone is sick, climate science, meteorology, management science, and law.

   To be familiar with everything, they are all sciences that are not in his major specialization, and a guest of this nautical marine sciences is his primary specialization and many branches.

  He must pass all of this by 70%.

  The captain studies certificates, marine courses, and other courses in various sciences that may exceed 30 certificates, in contrast to the basic marine subjects that the article cannot mention

  As he is the first responsible for the ship that raises the flag of the state in the seas, oceans, channels and international shipping lanes

  And on it some other responsibilities that the article cannot mention ....

  The certificates of the captain, engineers, marine officers and sailors are renewed every 5 years, and all his inevitable certificates, marine passports and educational courses are revoked, he returns to the zero point and begins his studies again. Compulsory academic system in all parts of the world belong to the International Maritime Organization of the United Nations as the certificates are international certificates.

  It is the only field in the world from which graduates remain associated with studying at the college or academy for the last practical and scientific life of which is (a mandatory global system is mandatory)

  Plus, as the ship's maneuvering in the water is more difficult to maneuver and more difficult than maneuvering the aircraft and more difficult than any maneuver for any machine to march or otherwise (according to an article from the UKHO office in 2017)

  The work of the sailor is classified as one of the most dangerous, most difficult and dangerous jobs, and the error in it has great harm on the human and economic side, according to (the BBC) documentary film. The sailors November 2017)