WHAT'S A VPIRB?

A VPIRB (VHF Position Indicating Radio Beacon) is a Maritime Survivor Locating Device (MSLD), specifically designed to alert the parent vessel that they have lost one of their crew overboard.

In most man overboard (MOB) situations, the vessel from which the person came from is in the best position to render immediate assistance.

A VPIRB is equipped with an internal GPS receiver, and uses VHF DSC (Digital Selective Calling) and synthesised radiotelephone (voice) transmissions to broadcast this GPS position to all vessels and shore stations in range.



DSC is a very suitable technology for a MSLD, as it allows alerting of both the parent vessel, and all other DSC-equipped vessels in the immediate vicinity.

Personal Emergency Position Indicating Radio Beacons (EPIRBs) have saved many thousands of lives over the years; however they rely on shore infrastructure to process and then re-broadcast an alert message to ships in the vicinity of the person in distress. Depending on the location of the EPIRB, this could involve delays in the order of hours.

A VPIRB activates automatically on contact with water, or it can be manually switched on. It will provide alerting ranges in the order of 2 nautical miles from a typical small boat. Larger vessels and shore stations with higher antennas will receive the distress signal over longer ranges.

At present, there is only one VPIRB model available, the Mobilarm V100 VPIRB.
HOW DOES A VPIRB WORK?

The VPIRB can be automatically activated from the 'armed' position when the device is immersed in water. Manual activation is also possible.

The VPIRB transmits an alert, a unique identity number and the MOB's exact GPS coordinates to all vessels in the vicinity, including the distressed mariner's vessel, as well as to any land-based VHF receivers in range.

The VPIRB automatically sends an initial "Mayday - man overboard" alarm in DSC data message format, using VHF DSC (channel 70), to alert the parent vessel and other vessels that the MOB event has occurred.

As soon as a GPS lock is obtained, typically in under 30 seconds, the distress call is transmitted again with latitude and longitude coordinates, using VHF DSC and in a synthesized voice format on VHF marine channel 16. This is repeated at regular intervals to update rescue personnel with the MOB's current position.
Overview of the VPIRB Rescue Anatomy
Overview of the VPIRB Rescue Anatomy
NOT JUST ANOTHER EPIRB

Conventional marine personal locating beacons such as personal EPIRBs must be manually activated to send any signal - as mandated by regulatory authorities. This may be difficult or impossible to do if a MOB is injured or unconscious. Personal EPIRBs transmit an emergency signal to a remote onshore location, which can introduce unnecessary delay in the recovery of an MOB - greatly reducing their chances of survival.

VPIRBs provide instant notification to a mariner's vessel that a MOB event has occurred, alerting the people who are in the best position to rescue the MOB and ensuring they are deployed as soon as possible.

VPIRBs do not require any additional dedicated receiving base stations, 121.5 MHz directional finding equipment or satellite rental time. With a VPIRB, as long as a VHF radio is onboard, no other equipment need be installed; the VPIRB uses only existing industry-standard VHF marine radio networks.

source

GMDSS - A WAY AHEAD

The following is a summary of a presentation made to the 2010 RTCM conference in San Diego, USA.

GMDSS - A WAY AHEAD

What’s wrong with DSC?

 These days, the GMDSS is all about Satcoms, and the drive for more and more bandwidth to ships. No one uses the GMDSS HF gear…it sits in the corner of the bridge, gathering dust….right?

  
Wrong.

A typical GMDSS HF Coast Radio Station receives, on average, 6000 DSC calls per day. 6000 calls, distributed over 2 – 16 MHz….Even using a modest antenna system, you can hear calls on the 12 and 8 MHz DSC channels at least every minute, all day.

 

What’s the problem?

 The system is clearly being used and is working well technically – ships are communicating with coast stations and other ships.   DSC was originally designed to automate radiotelephone calls between ships at sea and telephone subscribers ashore.  However, satellite/cellular communications have replaced HF radio-based telephone systems for merchant ships. The result is that DSC is effectively designed around a function that no longer exists. This is evident in the number of redundant tele-commands incorporated in the DSC standard.

 

Confusion….it need not be so…

One of the great advantages of using a PC for coast station DSC software is that the operator interface can be easily modified or redesigned.  We can change labels, we can alter the layout and we can hide the more baffling DSC tele-commands to make the system operator friendly.   Alas, ships can’t do that...  They are faced with a myriad of menus, containing many superfluous commands, all which are never used. 

The DSC technical specification, ITU Resolution –M.493, has been revised 13 times since it was first published.    Many of the revisions incorporate very important operational and technical updates, which make the system much more efficient and easier to use.  Equipment performance standards are updated as a result of the revisions, and DSC manufacturers dutifully incorporate these updates into their latest products. 

However, where the good ship DSC hits the proverbial iceberg is real-world implementation - the revised performance standards apply only to new equipment…

There is no requirement for ships to update their DSC equipment to comply with new specification.

So, as a result, ships are sailing around with 1^st   and 2^nd generation DSC systems….old and clunky, full of redundant tele-commands, and thus a nightmare to use….

To their credit, the USCG has identified this problem. 

They put a paper to the recent IMO COMSAR meeting proposing that SOLAS Chapter 4 be modified to require the latest DSC software version to be used. This issue is moving forward through IMO, but it will take time to implement…

 

Oversight…

Despite all the DSC traffic, many ships are still making fundamental mistakes with the system. 

Using the latest software will go some way to fixing the problem – but, what is really needed is for some central body to take charge of DSC, and conduct an active monitoring and education campaign.   

 Internet technology allows remote control of DSC shore stations from anywhere in the world. 

 A number of DSC HF monitoring stations could easily be controlled from a central point, to provide world-wide coverage.    It would be a simple matter to match a ship’s DSC identity number (MMSI) to her Inmarsat number.   Ships which regularly breach DSC operational standards could be sent a polite reminder (or even an operational guide) via Inmarsat….. 

 

Don’t let small craft near DSC…!

 Many SAR agencies are reluctant to promote VHF DSC to recreational users because of a fear of false alerts. Any automated distress system will suffer a certain percentage of false alerts, either malicious or inadvertent.  Training, education and equipment design will address the majority of these problems - but there is one solution that would really solve the DSC false alert issue…Mandate that all DSC equipment is to be fitted with an inbuilt GPS/GNSS receiver.

• 
  
  
  Every distress call will contain a real position.
• 
  
  
  This will all but eliminate malicious false alerts.
• 
  
  
  Inadvertent alerts will be identified and localised.

 GPS receivers are small and cheap – they could be easily integrated into a VHF radio.

  

In summary - Fixing DSC…

• 
  
  
  Remove the remainder of superfluous tele-commands from the standard, to simplify the system as much as possible…DSC isn’t going to be used for setting up phone or fax calls……
• 
  
  
   Mandate updating of ship equipment to comply with the latest standards.
• 
  
  
   Become pro-active with monitoring and real time education/mentoring.
• 
  
  
   Fit an integrated GPS receiver to all new DSC radios.

 

 

UPDATING THE GMDSS

Let’s get rid of DSC….it is all too hard…

There has been ‘corridor discussion’ at IMO of removing MF DSC from Sea Area A2 and possibly A3 – this smacks of the ‘turn it off and ignore it’ philosophy demonstrated by some ships.  Abandoning DSC would be a serious mistake.   The inherent strength of the GMDSS is the multiplicity of communication links it provides over different satellite and terrestrial bearers.   If one system is down, you always have an alternative. 

 MF DSC provides ship-ship and ship-shore alerting in Sea Area A2 and ship-ship alerting in Sea Area A3. 

 What do we replace it with?  Satcom systems can not provide direct ship-ship alerting to all other vessels in the area of the ship in distress. Inmarsat C has demonstrated its worth time and time again for ship-shore alerting – it is one of the GMDSS’ standout sub-systems.  However, it can not replace DSC.

Yes, DSC has problems – but we must fix them, not just give up and say it is all too hard…..

 

NBDP?  Ditch it…

NBDP (aka radio telex) is a clunky old system that (to my knowledge) has never been used in anger for distress traffic.  A3 ships already have an option to dispense with it – this should logically be extended to all A3 ships. I know if the water was coming in the bridge wing door, I would rather be talking into a microphone than trying to type on a keyboard…

 

A truly global system?

Australia is still effectively running 2 distress systems in parallel – GMDSS and pre-GMDSS.  Australia is not alone in this – many developed nations still run old and new marine radio networks.

 Many areas of the world have no GMDSS infrastructure at all…

 Why? The GMDSS has been in place for more than 10 years….

 If we are going to modernise the system, then surely we need to start with making it universal.

 

Way ahead……it isn’t rocket science….

 

·         GMDSS shore infrastructure needs to be installed in the Pacific.

 

·         Marine Radio equipment standards for smaller, non-SOLAS vessels need to be modified to include DSC. 

 

·         Governments need to amend their marine legislation to require DSC equipment to be fitted to all ships - large and small.

 

·        GMDSS Sea Area A1 needs to be declared in areas of high shipping activity.

 

·       Governments need to develop a transition plan to eventually phase out voice watchkeeping and replace it with automated DSC watches.

Source here

Maritime Communications

Shore side Communications technology has improved dramatically in the last 20 years but maritime Communications has always struggled to keep up with the changes at the same pace.  This is due to a number of factors, from cost of the systems to amount of work required to refit a ship with a new communications system.  Work that can only been completed when a ship is available to go into an extended period alongside, ie drydock.

Though Communications at sea has evolved (albeit a few years behind land based systems) it still catches people out when they first go to sea, that they cannot just take out their mobile phone & ring their contacts for a chat in the middle of the Atlantic..

I do remember an incident at sea in 2004, when a Cadet, sitting in the Mess complained to the Radio Officer because the quality of his phone call to his mum made from his cabin left a lot to be desired…

The Radio Officer with over 15 years of seagoing experience at that time, slowly folded up his 2 week old newspaper & “gently” put him in the picture as to how Radio Communications were when he first went to sea & that he should be amazed that he could just pick up his own phone in his cabin & directly dial his parents home in England….sighting CW telegrams & very crackly Rad-Telephone calls via Portishead with your parents having to say “over” before you could speak….The young cadet went away with a lesson well learnt.

Which brings me on to the serious bit of the article, whilst Telecommunications at sea have been improving quickly, it must be realized that most crew members do not have access to the same telecommunications infrastructure as people ashore, although it really is obvious that the most pressing community who require great communications would be the Seafarers who spent 80 percent of the year away from their families & loved ones.  Seafarers also need to have access to more Marine specific Communications, such as :-

·         Being able to send & receive Distress Alerts or safety information.

·         Being able to communicate with other ships.

·         Being able to communicate with shore side Maritime agencies.

Due to the International nature of shipping, these Communications systems must be internationally interoperable & this is where the delay in having upto date Communications systems on ships stems from.  As the new systems must be interoperable, affordable & acceptable to the majority of Maritime Nations.

All Maritime Agencies do not advocate Mobile Phones as a substitute for Maritime Radio Distress & Safety Systems.  Although Mobile Phones do have their place onboard as an added measure of safety & with the advent of mobile Satellite Phones there is even more Communications available to the Master in the event of an emergency at sea.

Mobile phones generally cannot provide ship to ship safety communications or communications nor provide the ability to make a distress call on a Mobile phone, as only the one party you call will be able to hear you.   Most Mobile phones are designed for a land-based service. Their coverage offshore is limited, and may change without notice.  Locating a Mobile caller, if calling from sea, is almost impossible.  Even with the global phenomenon of Mobile Phones, the humble Radio Transmission still plays a vital part in Maritime Safety.  It is a vital message to pass along to others who think that the Satellite Telephone is a suitable / viable alternative.

Two United Nations-chartered organizations, the International Maritime Organization and the International Telecommunications Union, are responsible for defining and regulating maritime telecommunications systems. The most current system adopted by these two organizations is the Global Maritime Distress and Safety System, or GMDSS.  Morse wireless telegraphy, used by ships for distress and safety communications since the beginning of the century ceased worldwide on February 1, 1999. 
This Radio Operator still remembers making his last CW (Morse) Transmission to a Coastal Radio Station in the afternoon 31^st of January 1999, logging it into the CW transmission log.  Ceasing watch on the circuit.  Closing the logbook & sending off to be archived for records.  A sad day.

Some more informaion on the AIS SART.

JOTRON



Tron AIS-SART - Approved by BSH
GMDSS SEARCH AND RESCUE TRANSMITTER


• Adopted by IMO RES MSC. 256 (84) as an alternative to 9GHz SART

Proved performance:
• Up to 10 nm from a SOLAS ship with AIS class A transponder
• Up to 40 nm from a SAR helicopter (altitude 1000 ft)
• Up to 130 nm from a SAR aircraft (altitude 20000 ft)

• Unique AIS technology contribute to a more effective and less time
consuming SAR operation, due to superior position accuracy
• The AIS-SART is detected on both AIS Class A and B and AIS Receivers
• Small and compact
• Jotron Tron AIS-SART use the same acessories as the Tron SART20 Bulkhead
bracket, pole, life-boat bracket and neoprene protection bag)

Will be shown on ECDIS or Chart plotters as a RED Circle with a cross inside.

AIS SART – New Technology And The Sharing Critical Information

---

AIS has been a revolutionary product and, regardless of your opinion on its use, has changed the way mates handle heavy traffic situations. Jotron, makers of various SOLAS compliant marine safety electronics, is looking to bring this revolution to Search And Rescue operations with the introduction of an AIS enabled Search And Rescue Transponder (SART).
The device will work similar to traditional SARTs but, rather than show the position of a lifeboat on your 3cm radar, will transmit the exact GPS coordinates to all AIS enabled devices within VHF range.

2010 Maritime Radio Day

Maritime Radio Day is held annually to commemorate to the era of nearly 90 years of manual maritime radio.

It does only work in wireless telegraphy (wt).
All radio amateurs are invited to take part and work especially with former radio officers of the merchant marine and navy.

See page Rules for detailed information and take part in this CW-only event.

This year's event will be held from 12h00 UTC 10th April to 12h00 UTC 11th April 2010.

Frequencies: 1854, 3520, 7020, 14052, 21052 and 28052 kHz.

Complete information and rules can be found at: www.doese-apprt.de/mrd/index.html


More here