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Maritime Safety Nets and Unmanned Ships


Robert Connolly surveys the current state of maritime safety and environmental technologies and looks into their future



Robert Connolly surveys the current state of maritime safety and environmental technologies and looks into their future, before detailing Australian maritime communications and coping with the recent stormy weather.


The development and use of maritime electronic navigation and communications are constantly undergoing improvement. Over the last few years, we have seen the introduction of Class A Automatic Identification System (AIS) for commercial shipping over 300 Gross Registered Tonnes (GRT) and for all passenger-carrying vessels.

Furthermore, a lower-specification Class B AIS system was developed for use by smaller vessels, for example, fishing vessels and leisure craft. These technologies greatly added to the safety of vessels on the water, compared to just having radar. This is because much more information on vessels that may create a navigation hazard is now displayed using AIS. Details include the vessel’s name, size, course and speed, making it much easier to avoid a potential collision, particularly in busy waters close to ports.

AIS was further developed to display navigation aids and potential hazards to vessels.

In addition, some of these technologies provide real-time data on weather and tidal state at some ports.

We have also witnessed the comprehensive implementation of Digital Selective Calling (DSC) on MF, HF and VHF marine bands. One of its main functions is to quickly transmit a distress message at the push of a button, providing data, not only the distress vessel’s name, callsign, position (when linked to GPS navigation), but also on the nature of the distress situation.

From a mariner’s point of view, this is a much quicker way to send an emergency signal, especially when a vessel is on fire or rapidly sinking.

For quite a few years, there have also been NAVTEX Maritime Safety Information (MSI) transmissions, using 518kHz for international English and 490kHz for local language broadcasts. MSI broadcasts, transmitted in a similar fashion to MF NAVTEX, are also available on several HF frequencies.

On top of this, satellite communications systems have been developed for shipping, delivering, not only up-to-date MSI information but also a platform for the provision of internet and mobile phone communications for passengers and crew.

Passengers on cruise ships and ferries often complain that onboard internet access is slow, compared to the speeds available on land. However, many are forgetting that they do not have a fibre-optic phone cable trailing behind the vessel.

Certainly, there is much ongoing development, to increase the speed of satellite communication; but, in my personal opinion, speeds will not become the same as land-based, high-speed, internet and will not be as fast as the new mobile 5G speeds that are being developed and are due to be rolled out on land during 2020.

This is due to the nature of satellite communications using uplinks and downlinks to a satellite in space.

Another major development a few years ago was the introduction of the use of electronic charts for navigation, consigning the days of calculating manual position plots to the maritime history books.

These developments have upgraded maritime safety, and, it seems safe to say, other advances will appear in years to come.


Vessels, Cleaner and Unmanned

The maritime industry is currently developing cleaner fuel systems to reduce atmospheric pollution from their engine exhaust gases. They do this by applying a variety of methods, from fitting exhaust scrubbers, or using alternative fuels that cause less pollution, to the deployment of electric or wind power.

In some cases, a combination of methods is being used.

Another current change in the maritime industry is the use of ships that do not need any onboard crew. Some successful trials have already been carried out in this area. Most of you are probably aware that, for a number of years, the technology required to fly an aircraft without a crew has been available and is being used to control Unmanned Aerial Vehicles (UAV).

Recently, a UAV even flew successfully across the Atlantic Ocean. Now, the plan is to have unmanned vessels on the high seas, on the basis that, without the requirement for crew accommodation, there would be more cargo space available, hence potential greater profits for shipping companies, while at the same time lowering the cost of goods for the consumer.

Obviously, control of such ships would be maintained from shore-based location, by means of satellite communications between the controller and the ships being controlled. I suspect that this would not only include data communications used for steering the vessel but also extend to live video feeds from the vessel coupled with AIS information, transmitted to avoid possible collisions.

For a number of years, aircraft have been capable of flying automatically, but this has never been attempted on a commercial passenger aircraft, due to the lack of confidence in such automation by fare-paying passengers, who would have serious concerns regarding something going wrong and nobody there to intervene. I also think that this would apply to passenger ships if there was an attempt to control them remotely. For that reason, I think automatic control would be confined to cargo vessels.

However, there are also some other problems to resolve. Currently, ships are carrying engineering staff to look after the engines. When a fault occurs, maintenance crew can normally repair it using replacement parts, or they can make a new part in their workshop if required.

I cannot help wondering how an engine failure of an automatically controlled ship, located in the middle of the ocean, would be dealt with if there were no crew onboard.

Another question concerns the use of pilotage. Many ports require the use of a pilot for vessels to safely enter and exit ports. Pilots are located at or close to ports so would they also have to use virtual reality?

[see our feature by John Periam, on the Solent Pilots, in this issue of RadioUser – Ed.].


Security and Communications

In this context, the biggest ‘headache’ of all is the question of how to ensure the total security of the system, in order to prevent a major disaster involving environmental and/or human lives, by persons with ill intentions.

While satellite communications can be used for controlling speed and course, there is a risk of, whatever secure system is used, being compromised by either a foreign power or other persons with criminal intentions.

Many maritime authorities already have worries regarding the possibility of GPS navigation being interfered with, either intentionally or unintentionally; this is something I have mentioned in previous columns.

I think that automatic control of small cargo coasting vessels, using ports that do not require pilotage, may be safely possible in the next few years, but I cannot foresee such technology being used for larger ocean-going vessels in the near future.

Just like the situation with driverless vehicles, there is still a long way to go before ship automation is proven to be safe. Having said that, some small-scale trials have been successful, but these have always been carried out with a crew onboard, ready to take over if something went wrong.

Whatever happens, I do foresee an increase in the use of both terrestrial and satellite marine communications in the coming years, especially in the area of data transmissions.


Maritime CB, Down Under

The majority of countries worldwide rely on marine radio communications – either through DSC or by voice – for small craft, to call for assistance when they find themselves in difficulties.

Interestingly, Australia not only uses normal MF/HF and VHF marine communications but also an extension of their 27MHz Citizens Band radio, reserved for maritime use.

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The 27MHz Service is not monitored by larger ships, as it is designed for recreational craft users. However, most Australian coastal volunteer rescue stations monitor transmissions on Channels 86 and 88 in that band.

This is a low-cost, license free, option, compared to traditional marine VHF radio. It has the further benefit that no formal qualifications are required to use this band, making it popular with recreational users.

The 27MHz transceivers are capable of sending distress alerts, receiving weather forecasts and marine safety information. In addition, the equipment is cheaper than ‘normal’ marine VHF radios.

The standard working range on 27MHz is indicated as being ten to 15nm.

Table 1 details the frequencies available for maritime use in Australia.

These coastal rescue stations form part of the Australian Volunteer Marine Rescue (VMR) coastal radio network and similar services. Much of their role would seem to be similar to the UK Coastwatch Organisation, with their primary function of logging vessel movement, providing weather and safety message reports, and receiving distress and emergency transmissions.

The VMR stations Down Under also provide maritime rescue, using their own state-of-the-art craft. In addition to the 27MHz Channels 86 and 88 distress and calling channels, the VMR service also monitors ‘normal’ VHF marine transmissions on Channels 16 (156.800MHz) and 70 (156.525MHz) DSC, along with either Channel 80 (157.025/161.625MHz), 81 (157.075/161.675MHz), and 82 (157.125/161.725MHz).

In Australia, marine VHF Channels 80, 81 & 82 are repeater channels, used for passing on information on ship movements and on the safety of vessels and persons.

A number of VMR stations also monitor some selected HF frequencies and have a transmit facility on 2154kHz. Moreover, some stations possess a VHF DSC facility.

Each Australian VMR station is allocated a Maritime Mobile Service Identity (MMSI) number for VHF DSC calls. From time to time, when monitoring DSC MF/HF traffic, some of these MMSI numbers have appeared in HF DSC test acknowledgement signals.

I carried out extensive research into these several years ago and established that these stations are not equipped with HF DSC transmitters. It would, therefore, seem that the Australian Maritime Rescue Co-ordination Centre in Melbourne, which is responsible for HF and HF DSC communications, retain these MMSI numbers in their ‘auto-DSC’ (test acknowledgement) database. As long as that MMSI number is valid, the test acknowledgement is transmitted using that VMR MMSI.

In the UK, we sometimes see MF DSC test acknowledgements coming from Coastguard stations, which were closed several years ago. This is for the same reason: The correct MMSI number for a closed station remains logged in the database.


The Impact of Storm Ali

September saw the arrival of Storm Ali in the British Isles. Some parts of Ireland were hit hard, with winds of up to 90mph, as recorded a few miles from here.

Close to my location, the RNLI All-Weather Lifeboat at Newcastle, Co. Down, was launched, at the height of the storm, to go to Newtownards Sailing Club in Strangford Lough, to attend a weather-beaten yacht that was believed to have somebody on board. The sea passage to Strangford Lough was described as challenging, with a Force 8 gale blowing.

On arrival, the lifeboat crew confirmed that there was nobody on the yacht. It was then tasked to go the aid of another yacht several miles away, which was found to be drifting. Unfortunately, by the time the lifeboat reached the vessel, there was nothing the crew could do, as the vessel was on the rocks, on an ebbing tide. It also had nobody on board.

The crew commenced its return to the station, only to receive a third tasking from a yacht in difficulties. The lifeboat crew established a tow line and successfully towed the yacht to the safety of a nearby marina. On leaving the relatively sheltered waters of Strangford Lough to return to the station, the lifeboat crew once again faced mountainous seas and the Coxswain decided to stop in a coastal fishing port for an hour to allow conditions to improve. The lifeboat and its battered crew returned to station after seven gruelling hours at sea.

Unfortunately, Storm Ali also damaged my main MF/HF receiving aerial, a Datong AD370 outdoor active aerial, blowing a piece of debris from a neighbour’s shed roof. This piece seems to have hit the upper-element mounting post, which comes through the plastic case of the head unit.

My photograph (Fig. 1) shows the Datong AD370, offset from the main mast. I suspect the weather has also allowed rainwater to penetrate the case, as we had heavy rain during the storm. The active aerial carries power from the DC power supply up to the coax feed cable, and to a circuit inside the head unit.

As a result, my general coverage receiver is currently as deaf as the proverbial door post. Until I drop the aerial array, I will not know if the AD370 is repairable.

Meanwhile, I have purchased a new mini-whip active aerial to either replace it or, if I can repair the AD370, supplement it.

I would like to have the new mini-whip ready to attach to the mast in one operation when it is down.

Finally, my thanks to Kev Hewitt for this month’s picture, in Fig. 2. It shows the submarine HMS Talent in Gibraltar.

Until the next time, Fair Winds.


Table 1: VMR Frequencies for Maritime Use in Australia


Station                                                MF / HF Frequencies Monitored

Adelaide West Beach                         2032, 2182, 2524, 4125, 6215, 6227, 8291

Adelaide North Haven                        2182, 2524, 4483

Edithburgh                                          2032, 2182, 2524, 4125, 6215, 6227, 8291

VMTR Port Lincoln                            2524

Seaton                                                 2182, 2524, 4125, 6215, 8291

VMT Tumby Bay                                 2524

Wallaroo Base                                    2032, 2182, 2524, 4125, 4535, 6215, 6227, 8291


This article was featured in the December 2018 issue of Radio User