Friesland wartime history     by Willem de Jong    <   page 11   > 

Texel & Den Helder




Leeuwarden Airfield


Harlingen & Harderwijk

Occupied Harlingen

German Radar




St. Jacobparochie

Rottum Island

     Sink the Scharnhorst!
     12 Squadron Losses
     Runnymede Memorial 


Deanweb - the Forest of Dean Directory

Artillery and Radar Installations on Schiermonnikoog and Terschelling



A navy air defence battery was built west of the lighthouse in 1941. Four artillery emplacements contained a 10.5-cm anti-aircraft gun each. A fire control post was centrally located and it was supported by a FuMO 214 ‘Würzburg Riese’ operating as a Seetakt radar. The complex also contained a FuMO 2 radar, and a pair of 2-cm guns located on the east and the west side of the site provided the anti-air defense. Some of the complex is still intact.This long chain of defences included Schiermonnikoog as a link. An entire concrete bunker complex was created, manned by 200 German soldiers, tasked with both air defence and information gathering through specialised listening equipment.

On Schiermonnikoog a complete blockhouse village was constructed with the purpose of air defence, including radar and listening equipment. The blockhouse Wassermann has been developed to serve as the basis for a huge radar antenna. Next to that there was capacity for an electricity generator and data translation/interpretation. 

The standard for this type of the blockhouse construction has become known as L480. The radar antenna consisted of a 40 meters tall steel cylinder with mounted antennae. This type of radar carried the name “Wassermann-S(chwer)” [Schwer = heavy]. This enabled the management of approaching airplanes in the airspace within a range of 300 kilometers [over 186 miles]. 



 German war-time emplacements





Some photos now of the "Luftwaffe-eyes" on Schiermonnikoog island (Stellung Schlei)


Left - a combination of a single Freya - antenna (below) and a Köthen - antenna (above); the last one was in particular for the "free waves", without British jamming.

Right - a Wasserman - "tower" (a series of Freya - antennas, forming together one "long range eye"). Standing there is Ab. A Jansen the well-informed author of "Gevleugeld Verleden" (History with Wings)

Such a Wasserman-tower was also build in West-Terschelling / Terschelling isle, on one of the highest sand dunes of the island, between the village and the beach on the Westpoint (Groene Strand). RAF bombers or fighters never destroyed these radar - equipments. This the people of Terschelling etc. didn't understand... these things were so deadly for Bomber Command planes !!!

First series of new radar FreyaLZ (FuMG-42G) was produced by GEMA Germany in November 1941. The base of radar was designed as standardised construction for frequent change of location in battle area. Radar station was powered by external generator (380V).

Later versions of Freya-LZ were named FuMG-401. They were redesigned for longer distance. Willem




Wassermann Tower at Schiermonnkoog.  A German soldier climbing to the top of the tower. See the triangle construction, built up from aluminium parts / profiles etc.  





Photo 1 - a "knocked down" Freija-antenna, after liberation in 1945 (?).


Photo 2 - a Würzburg (Riese) - Funkmessgerät on S'-oog island (as far as I know type FuMG 62 - 560 MHz - max. 29 kilometres / 18 mi.); it was a "target-following-radar", for the short range, for only 1 airplane per turn (!). 2 of them were used in combination with that Freya-Gerät: one was following the own fighter, the other the enemy bomber.

Photo 3 - a German radar-antenna (Freya ?) under camouflage.

Of course, I don't know all the (technical) details - like many people of Schiermonnikoog for most of the islanders the beach and the dunes were "no-go-zone" in those years - but the older, still living people can appear as a witness: "it was really all there, standing in "Skys" beautiful sandy landscape, between marrum, heather and buckthorn"





On the left a camouflaged bunker for an electric power Diesel-aggregate on Schiermonnikoog; which the Germans needed for their searchlights for example, while most of the island didn't have power at all.


Right photo shows one of the searchlights, of the Flak-battery in the dunes near the water reservoir tower, Schiermonnikoog isle. 





On the left the installation in March 1941 of one of the "Flakgeschütze" in a so called "open formation bed" ("im offene Bettung"); the crane they are using for this  heavy work could lift 4000 Kilograms, as you can see above. 


The right hand photo shows daylight training of "Marine-Flak-mannschaft" on their Flakgeschütz in the dunes, on Schiermonnikoog (2-cm-Flak 38 ?).





Construction work of the Wassermann-bunker (1942) and segments of a Wassermann-S(chwer) pylon, yes or no?




One of these mails came in from Mr. Rene Voulon ( He was sending me a photo about the Wassermann-bunker on Schiermonnikoog Island; it's showing us today's "antenna-location" on the rooftop of the bunker.

From his writing I learn there is a lot of discussions going on in the "Fortificatie Forum" ( about sabotage yes or no (?). We spoke about earlier, as you know, and our website (text and photos on page 11) is part in this discussions also !

By the way, he was praising our site, saying: " Mooie site van je " (= nice site of you --> read "you people"). And he was also talking about a photo, I send you now (in 2 parts); showing the construction work and the segments of the never erected Wassermann-S pylon. 

Willem - April 16th 2012



The Luftwaffe successfully used FREYAs in colaboration with Wurtzburg-Riese and before end of WW2. got cca 400 units of all versions of FREYAs. Special version of Freya was FuSAn 730 FREYA EGON I. 

This radar was used specially for navigation of fighters and bombers. Distance: 30-200Km

Freya was a metric rotating search radar with a range of 125 miles. It operated on a 2.5 metre wavelength with a power of 20 Kw. PRF was 500 and pulse length 3 microseconds. It had "bed spring" dipole array aerials, the one for receiving being mounted above the transmitter array and the whole thing was originally designed to be trailer mounted. 

During the first winter of the war Freya radars on the German islands caused severe losses to our bomber formations. Its precision was such that in May 1940 at Essen-Frintrop a flak battery shot down a bomber that could not be discerned visually.


"On the island of Schiermonnikoog they built a radar installation of the Wassermann type. (location above). This enabled the detection of approaching airplanes in the airspace within a range of 300 kilometers (over 186 miles).   

According to some sources, sabotage was the cause that an antenna was never installed, and therefore this Wasserman was never put into use.

“The steel mast had never been placed. The reason is probably due to the fact that, at the laying of the foundation for the mast, this was sabotaged. By the incorrect application of measurements the 40 meters high cylinder could not be placed. This Wassermann blockhouse on Schiermonnikoog is not only a rarity as far as its type is concerned, but is at the same time possibly a symbol for a memorable act of resistance."

Myth or reality? I would like to know more about this story. Willem's photos at the top of this page show a working Wassermann tower on the island.  Tom

And about that sabotage ? I do not know all in detail of course, but I think it's more a myth than a reality; the German "war machine", in this cause the building division "Organisation Todt", was a high tech, experienced and perfect run organisation, controlling every minute (check and double check ! ) the construction activities of the (Dutch) workers in the field. It would be suicide.......  Willem

Radar Equipment

The night-fighter battle against the RAF night-bombers, who were on their way to Germany most of the time, was an ultra-modern and secret battle for those times, certainly after 1942, using ground-radar, board-radar and wireless communication equipment, increasingly better and better every time (thus it was also an electronics war).

To give an impression of all these systems that the Germans were using, below are some photos of their equipment. By seeing this, we may now understand, that it was not only the "damned good pilot", and the victories claimed by aces of the Luftwaffe, who were important for the success of this type of warfare; but his radar and radio man in the background, and even the radar-post controller on the ground, who played a very important part in the success of the resulting battles.

The Schlei-stellung on Schiermonnikoog of course, was important in the same way as the Tiger-stellung on Terschelling ("brother and sister you could say"). It was the same too for Löwe (Lion) near Marum-Trimunt, and Eisbär (Polar bear) near Sondel, both on the mainland/South and East of Leeuwarden

In the dunes of the tiny island of Schiermonnikoog was the communications post. Construction of the complex was started in 1941 with a type 424 Küver bunker that was combined with a (similar) 431 and a 409 bunker. The complex included at least two FuMO 214 , Würzburg Riese and other radars.

At Terschelling, 'Tiger' consisted of some heavily fortified radar bunkers, including the impressive L487 'Bertha' bunker. This command centre collected data from the Flagrukostand in Den Helder, Salzhering, Schlei and other surrounding complexes.

In the bunker on the top floor were two Seeburgtisches. These consisted of a transparent frosted glass plate of 2.5 by 2.5 meters, which on the first was drawn a map of the combat section with the night hunting program it was responsible for and the second equipment displayed the 300 kilometers range of the Wasserman radar.

Altogether the Tiger complex included two FuM0 214 'Würzburg Riese' radars, two FuMG 402 'Wassermann' (large) and also a FuMG 39 G "Freya."



Designation Cross-Reference List














Photo 1 : Birds-eye-view from the top of the Wassermann-pillar. The photo is showing us the dune landscape around the "Seinpaalduin" and the radar-tower, and for the guys with "good eyes": they can see the concrete bunkers of the (German) West-battery on the island (Flak etc.).


Photo 2 : The entrance of the habour of West-Terschelling anno 1946 (photo taken from the upper-deck of the arriving ferry-boat). In the middle of the picture you see the little bell-tower on the roof of the church, and right there is the (very old) lighthouse "Brandaris", and before that, you see the life-boat-station (NZHRM-station); but for us, for our story, the left side of the picture is important: there is still standing, on the high "Seinpaalduin", the Wassermann-"tower".




Photo 3 : The foundation / underconstruction of the radar-pillar; this whole pillar with all the antennas fitted on it, could turn around, while "searching the best echoes of the planes" (in the background you see the "Brandaris" lighthouse, which the Germans also were using for a "look-out-post").  

This Wassermann 'S' was built up from a steel-cylinder, and this construction had no rigging / steel cables to hold it up. It was built a distance from the camouflaged Wassermann-bunker because of the "noisy construction" (singing in the seawinds) as I told you before; even German soldiers wanted to sleep from time to time..... and that wasn't so easy, with all these "flieger-alarms",  and Flak-batteries firing etc. 





Parts of the "knocked down" pillar. In the background of the photo on the left you can see the entrance of West-Terschelling habour.

In 1948 the Dutch were blowing up the under-construction of the system. The first time they didn't succeed (not enough explosives!) - results: steel parts of the tower were falling down in West-Terschelling village, in one of the streets below the "Seinpaalduin" (no one was wounded / some little damage). The second time the whole pillar was cracking / falling down, in a "beautiful sandblast".



Mrs. Attje Lak of West-Terschelling, who is caring for the war grave of F/O Maurice Gordon Sheerman (Longway Cemetery - grave 108), was mailing me last week 2 photos, on which a member of her husband's family as far as I understand (she will give me more details about him later on she wrote). These photos are really beautiful and very interesting for us, because...... they are taken on top of that Wassermann - S radar tower (!), thus about 60 meters above sea level, ± 40 meters above the ground (on high sand-dune) and taken after the war of course (somewhere between 1945 - 1948, after liberation and before demolition. Looking at these pictures, one thing is very clear: this young man, as well as the photographer, were two 'climbing billies' without fear! They were looking down over the village, over the harbour, over the lighthouse too, and even almost over the entire island and the surrounding waters.  Willem




Major General John Dutton (Johnny) Frost CB, DSO & Bar, MC, DL (31 December 1912 – 21 May 1993) was a British airborne officer best known for being the leader of the small group of airborne forces that actually got to Arnhem bridge during the Battle of Arnhem. He was one of the first to join the newly formed Parachute Regiment and served with distinction in many wartime airborne operations until he was injured and captured at Arnhem. His army career continued until his retirement in 1968.

Frost distinguished himself in Operation Biting. On 27 February 1942 C Company, led by Frost, dropped into Bruneval in France to dismantle and steal the radar dish and components of the German Würzburg radar. After a short fight they captured the components of a vital radar unit and a German expert before being picked up by the Navy. The operation had lost three men killed and seven were badly wounded.

It was a short, sharp, highly successful operation for which C Company received a hero's welcome in the Solent with Spitfires dipping their wings overhead and naval vessels playing 'Rule Britannia'. The raid had been carried out when the country's fortunes had been at a low ebb. Singapore had recently fallen and the beleaguered German battleships had escaped up the Channel.

The site from an aerial photograph

On 3 March the Prime Minister assembled the War Cabinet to hear the full story from those who had taken part in the raid. Afterwards he finally established - as a result of this action - his firm belief in the future of airborne forces. From this, the decision was made to go ahead with the establishment of an airborne division. Bruneval was the beginning.  Frost was awarded the Military Cross.

see   youTube film about the raid





The John Frost bridge at Arnhem






Willem's Introduction


Ameland in war-time


Wartime Texel  & Den Helder 


Friesland War-time Crashes


Ameland,166 & 75 Squadron




Friesland Cemeteries


Ameland Graves


Destroy the Scharnhorst!


Leeuwarden area




Destroy the Scharnhorst! 2


Wirdum Remembers


Terschelling 2


Destroy the Scharnhorst! 3




Sage War Cemetery


12 Squadron in World War 2


Schiermonnikoog  part 2


RAF Topcliffe & 424 Squadron


The Runnymede Memorial




Vlieland Cemetery


Vuren at war


Kallenkote Cemetery




Makkum Cemetery


Wartime Occupied Harlingen


Hampden AE 428, & Koudum


A Fatal collision?


RCAF 428 Ghost Squadron


Willem's War-time photos


Hudson & Ventura losses


Zwolle's ' De Groene ' group


Shipdham Airfield & the 44th




408 Squadron's Leipzig raid


68th Squadron's Casualties


101 Squadron


Friesland radar


Rottum Island


Lancasters DS776  & JA921


Bergen General Cemetery










back to 626 Squadron







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