The unique properties of the Magnetic Compass

Why the magnetic compass is still of vital importance

When I joined John Lilley & Gillie in 2004, the company had recently bought a 50% shareholding in a software company with the intention of producing its own ECDIS – the Navmaster ECDIS. Then, I was very quickly introduced to a former owner and MD of the company, who gave me a copy of a report he had written, which demonstrated the importance and unique properties of the magnetic compass. It was a good lesson in understanding the importance and functionality of both electronic and traditional methods of navigation and one that continues to be relevant today.

Whilst this is now 16 years ago, the relevance is still valid.

The ancient explorers and sailors used the sun and the stars to navigate but had the obvious problems with cloudy skies. Eventually, the magnetic compass helped to solve that particular problem.  

But the relentless and inevitable progress made in electronic and digital navigation in recent years, together with a corresponding increase in functionality, accuracy and reliability, has meant that the safety benefits of the magnetic compass have been less and less appreciated.

The report referred to above, included the story of the Bermudan flagged vessel, the Empress des Mers. In the early hours of the morning, when transiting through the Singapore Straits (where else) there was sudden loss of the 240-volt single-phase supply and both gyro compasses failed simultaneously. In addition, both radars, the GPS and most of the other navigation equipment also lost power.

The vessel was travelling at 11 knots when the incident occurred but the experienced British Master, Captain Richard Pettersson, was able to utilise his Standard Magnetic Compass to steer the vessel away from any danger. The Master had ensured that his compass was properly adjusted and insisted that his officers took azimuth bearings every watch to check and record the compass error and deviation.

The Master was therefore able to rely on the course steered by the Standard Compass, which was essential in such a dramatic and potentially dangerous situation. As he says, this was not and is not an isolated incident and usually these types of failures go unreported unless an accident occurs.

The status of the magnetic compass has changed over the years from the primary heading reference to an independent back-up which is usually only required in emergency situations, as described above. As a consequence, the magnetic compass suffers from being “out of sight and out of mind”.  But especially in its role as an emergency back-up, it is still vital that the magnetic compass is kept in good working condition and always ready and available when required. Captain Pettersson had followed SOLAS regulation by ensuring his compass was subject to regular maintenance by a qualified compass adjuster. As a result, it was ready for use in that emergency.

At this point, it is probably worth reminding ourselves what SOLAS has to say about the magnetic compass.

SOLAS Chapter V, Regulation 19, 2.1 states that “All ships, irrespective of size, shall have, a properly adjusted standard magnetic compass, or other means, independent of any power supply, to determine the ship’s heading and display the reading at the main steering position;”

That seems very clear and unequivocal. It is the intention of the legislators that a magnetic compass should not only be fitted but should be fully compensated and in full working condition.

So why are some ship owners and more worryingly flag states, ignoring this and allowing equivalence arrangements that blatantly contravene the regulations as set out in SOLAS?

The Chart & Nautical Instrument Association (CNITA) counts amongst its membership, most of the MCA qualified compass adjusters in the UK together with other qualified adjusters throughout the world. They report an increase in requests for remote adjusting, by phone or email, in order to negate the need to have an adjuster attend on board. This alarming trend is full of dangers and potentially could result in those compasses affected not being fit for purpose as required by SOLAS. A quick trawl of the internet reveals a number of companies and individuals actively promoting this service including one here in the UK.

The MCA does provide for the adjustment of the Magnetic Compass by ship’s staff as laid down in its Guidance on Chapter V, Safety of Navigation, Annex 13. 

“If a qualified compass adjuster is unavailable and the Master considers it necessary, then adjustments may be made by a person holding a Certificate of Competency (Deck Officer) Class 1 (Master Mariner). The compass must then be re-adjusted by a qualified adjuster at the next available opportunity.” 

But this does not condone the practice of “remote adjusting”. And what reassurance can we get that all compasses adjusted “remotely” are then re-adjusted properly by a certified adjuster “at the next available opportunity”? And therefore, that the vessel has a “…properly adjusted standard magnetic compass…” as required?

Equally of concern is the idea that the magnetic compass can be completely disregarded despite SOLAS requirements referenced above. There is evidence that certain flag states have now decided to allow the fitting of two or three gyrocompasses in place of the magnetic compass.

There is provision in SOLAS for equivalent arrangements as described in Chapter 1, Regulation 5 (a) which says:

“Where the present regulations require that a particular fitting, material, appliance, or type thereof, shall be fitted or carried in a ship, or that any particular provision shall be made,  the Administration may allow any other fitting, material, appliance or apparatus or type thereof, to be fitted or carried, or any other provision to be made in that ship, if it is satisfied by trial thereof or otherwise that such fitting, material, appliance or apparatus, or type thereof, or provision, is at least as effective as that required by the present regulations”.

Whilst I am in no way trying to denigrate the effectiveness of the gyrocompass nor indeed any electronic aid to navigation, the acceptance of two or three gyrocompasses meeting the equivalence requirement is clearly contrary to SOLAS Chapter v, Regulation 19, 2.1 referenced above.

No matter how many gyrocompasses are available, whether it is two, three or twenty-three, surely there is no way they can meet the requirement of being “…independent of any power supply…”?

Any yet, this seems to have been overlooked.

Putting to one side the huge cost aspect of this equivalence option, does not the mere fact that it has been found convenient to ignore SOLAS, open the door for other transgressions to be allowed or ignored?

Whilst the meteorological clouds are no longer an inhibitor to exploration and shipping, the metaphorical clouds caused by catastrophic electronic failure, are still a danger. It would be ironic would it not, if the immense advances to the safety of life at sea, cause an apathy towards the one aid to navigation that was, is and always will be, independent of any power supply.

 It is clear, or at least it should be, common sense dictates that for maximum safety, modern electronic aids to navigation should be utilised together with the more traditional and time-tested magnetic compass, as demanded by SOLAS. 

In order to ensure that your magnetic compass is “properly adjusted”, you must use an MCA Certified Compass Adjuster.  

Details of all CNITA members who satisfy this requirement can be found on the Compass Adjusters page of the CNITA website.

Glenn Heathcote
CNITA Compass Committee

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