This is a small part of the story of the indicator loop station built during WW2 as part of the Royal Navy's anti-submarine harbour defences of The Schelde River, Netherlands. It is located between Walcheren Island and Nieuwe Sluis, 3 km west of the village of Breskens. Six Indicator Loops were laid in 1945 to detect German U-Boats. After the war the number of loops were increased to twelve.

If you have any feedback please email me:

Dr Richard Walding  
Research Fellow - School of Science
Griffith University
Brisbane, Australia
Email: waldingr49@yahoo.com.au

- or better still, contact the researcher who provided all of the information on this page:
Paul Crucq, Veerseweg 110, 4332 BJ Middelburg, The Netherlands. Phone +31 118 414402.

  • Indicator Loops around the World (Home Page)
  • How an indicator loop works

  • The photos below were taken by Paul Crucq author of Code-Name 'Nelly', the story of British Radar Units on Walcheren and in Flanders, Defence of the Scheldt Estuary, December 1944-1945.

    With the surrender of the German garrison on Walcheren Island, early November 1944, the operations to clear the Germans from the riverbanks of the Scheldt were completed.  Minesweeping commenced but it was not until the end of the month that the first allied supply convoy eneterd the port of Antwerp. The Germans understood the importance of Antwerp and ordered their navy and airforce to bring the Thames-Scheldt convoy route to a standstill.  The German Navy made use of E-boats, the midget submarines Biber, Molch and Seehund and a small surface vessel Linsen.  The Luftwaffe operated with Junker 88 aircraft to lay mines in the convoy channel. The battle dragged on until the end of the war.

    To counter this threat, RAF 85 Group, 2nd Tactical Airforce set up mobile radar stations along the Belgian coast and on flooded Walchered.  The Royal Navy patrolled the river mouth with ASDIC (sonar) and depth charged where necessary.  On the seabed between Flushing and Breskens high lighthouse (pictured below), six anti-submarine indicator loops were laid to detect passing underwater craft.

    The lighthouse at Nieuwe Sluis, looking East. This was the site of the Royal Navy antisubmarine Indicator Loop Control Hut. A wider view showing Flushing. In the centre are some cranes which mark the location of the "De Schelde" shipyard which was there in WW2.

    Taken from the front door of the lighthouse with Flushing in the background (looking northeast). Looking west in the direction of the North Sea.

    Looking west with the lighthouse in the background. Taken from the pedestrian/bicycle ferry departing Breskens harbour back to Flushing.


    Royal Navy sailors off Breskens in January 1945 at the time when the loop station became operational. These men were responsible for laying the indicator loop cables and operating the control station. Sailor Charles Moulder is on the right (with his hands on the shoulders of the man in front). See below.

    Charles Moulder (left) on a gun at Breskens in 1945. Photos supplied by his daughter Pam Rider.

    Charles Moulder was born on the 28th November 1924 and joined the Royal Navy on 1st June 1943 under the NSAF Act 1939. He did his initial 3 week training on HMS Bristol and then on HMS Victory (22.6.1943 to 4.11.1943). He was sent to HMS Curlew between 5.11.1943 and 24.8.1944 where he undertook training in December 1943 as a Harbour Defence Operator and passed exams in Electrics Testing & I.C.E. [Institution of Civil Engineers accreditation probably] and also in Loops and R/T. His record continues:  HMS Claverhouse (Ubiquity) 25.8.1944 - 26.2.1945 and back to HMS Curlew 27.2.1945 until he was discharged. During his years of service, he undertook minesweeping training at HMS Lochinvar, sited at Port Edgar on the Firth of Forth. In 1943 Port Edgar had become a training centre for the Normandy Landings. The Royal Naval shore establishment transferred to Granton Harbour.

    Code-name Nelly

    The operations which ensued between December 1944 and May 1945 in the Scheldt Estuary are described in Code-name Nelly. The author Paul Crucq made use of the official records such as squadron Operation Record Books, debriefing reports, Navy records as well as documents from the Royal Artillery.

    Specifications: 80 pages, 24cm x 33cm, hardcover, satin gloss paper, 45 recollections of radar technicians, pilots, anti-aircraft personnel and civilians, 100 illustrations (photos and maps).
    Chapter 1: Westkapelle Lighthouse & 'Nelly', December 1944.
    Chapter 2: Operation Bodenplatte, January 1, 1945.
    Chapter 3: The Midget Grows, 'Seehunde', January 1945.
    Chapter 4: A New Radar at Oostkapelle 'Paddy', February 1945.
    Chapter 5: UFOs and U-Boats over the Scheldt, March 1945.
    Chapter 6: The Last Departures, April 1945.
    Chapter 7: Goodbye to 'Nelly', 'Paddy' and 15081, May-July 1945.

    It was a limited edition of 150 copies (English version), sold on a non-profit base. For the local market I produced a Dutch translation, mainly for the people in the village of Westkapelle where the RAF radar with the code-name 'Nelly' was set up on top of Westkapelle lighthouse. Paul still has copies of the Dutch translation in stock. Write to Paul Crucq, Veerseweg 110, 4332 BJ Middelburg, The Netherlands, or email pmcrucq@zeelandnet.nl