<i>Leading Aircraftman G Bidwell (left) and Corporal W Jones carry out maintenance work on an RAF mobile lighthouse at Mull of Oa, Islay, September 1945.</i><br>
Leading Aircraftman G Bidwell (left) and Corporal W Jones carry out maintenance work on one of two mobile lighthouses installed on the hilltops at Mull of Oa, Islay, as part of the 'Occult' Scheme.  This was an scheme to delineate the coastline of the British Isles to aircraft by a series of aerial lighthouses operating from a number of fixed sites no more than 15 miles inland.  They flashed letters in morse code which were changed periodically and were intended to be visible to aircraft approaching the coast.  The airmens' tour of duty at the site was two or three months, during which time they lived in a small cottage and maintained contact with their base using a wireless set.
Royal Air Force official photographer, Wilson J G (Plt Off)
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<td>This photograph <a rel="nofollow" class="external text" href="https://www.iwm.org.uk/collections/item/object/205212756">CH 16506</a> comes from the collections of the <a rel="nofollow" class="external text" href="https://www.iwm.org.uk/">Imperial War Museums</a>.
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