News Item

RIN SCG Lighthouse and MOD facility visit to Portland Bill

The RIN Small Craft Group Lighthouse and MOD facility visit to Portland Bill took place on Saturday 25 October 2015.

The weather was mainly dry but cloudy, so the views from the top of Portland Bill Lighthouse were better than expected. The Portland Race brought back memories to one RIN member of watch keeping in a tiny "S" class submarine in the cold and wet during one January, many moons ago. The Tour Guides at the Lighthouse gave the RIN SCG a detailed informative explanation of the workings of the Lighthouse optic and the old diaphone fog signal (no longer in use) and the modern electric fog signal.

After a welcoming lunch at the nearby Lobster Pot, 27 RIN members and their guests spent a couple of fascinating hours in the afternoon at the MOD facility.

The Site Manager, Barry Joplin, and his team, took us through the history of, not only the Portland site and their work but also the history of the development and use of magnetic compasses. We then visited the test site building designed to test for magnetism of all the equipment used on RN Mine hunters, as well as that used by the EOD bomb disposal team. We watched as they turned off the Earth's magnetic field to demonstrate the effect of a magnetic object on a compass needle aligned to True North. Even equipment that is supposedly non-magnetic has been proved to have some magnetism and failed their tests. Equipment they test can range in size from personal equipment used or worn by the bomb disposal teams to boats carried aboard the mine hunters and helicopters. We then moved on to the compass test centre, where we able to experience at first hand, the tests tat were carried out. So sensitive is the equipment that staff who need glasses have to wear special non-magnetic ones and ensure they have no loose change in their pockets that can impact on the results - even supposedly "copper" coinage nowadays is magnetic, as none of it is made from pure copper.

Our thanks go to both the Lighthouse Tour Guides and the QinetiQ staff at Portland Bill who came in on a weekend to show us round the sites.

Photo courtesy of QinetiQ.

  • 25 October 2015
  • SCG

Contact Us

The Royal Institute of Navigation
1 Kensington Gore

+44 (0)20 7591 3134

E-Mail Communication

The Royal Institute of Navigation periodically sends out email updates to its membership and those who have subscribed to events and conferences run by the RIN. In doing so, the RIN takes all reasonable precautions to ensure that the emails are only sent to those who have requested them, and that no third party can make unauthorised use of any email address to send out mailings.If you receive unsolicited mail from any address then please inform us at and we will take appropriate action.

Join the RIN

You can apply for any category of RIN membership by completing the online membership application form and paying using our secure credit/debit card payment system.

Join Now