FURTHER GERMAN COUNTERMEASURES.  
         
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  Part 4.  
         
 
         
  Reduced reflection (Rückstrahlverminderung).  
  The radar reflection of an object can be reduced by absorption or diffraction.  Absorption entails that the incoming radar energy is absorbed by a suitable material.  Diffraction results in the incoming energy being diverted in a direction away from the receiver.  The Germans were well aware about the theory, the mathematics and the practical application of what to-day has become known as Stealth technology.  On 9 - 10 Marts 1944 the Kriegsmarine held a conference (minutes in author collection) on radar technology, practical application and developments.  Agenda item nr. IX and X deals with the creation of false echoes and the absorption of radar energy.  The conference proceedings describes a material which can absorb 98 - 99 % of the energy from a 10 cm (3 Mhz) radar, which was the H2S frequency band.  The German name translates into an Electrical Swamp.  The Kriegsmarine applied Stealth technology to submarine coning towers and Schnorkels (Schornsteinfeger) in order to make them hard to detect on the ASV radar, which was nothing but a H2S adopted for maritime use.  One technique was the application of a rubber like material called Buna. In "Die deutschen Funkstörverfahren bis 1945" p. 142, Fritz Trenkle describes 5 absorption and 3 diffraction techniques known during the war.  Additionally one technique, where the radar energy is directed around the target, is described.  Was Lockheed aware of all of this when they designed the F-117 ?  
     
     
 

 
 

Picture - from the minutes of the above mentioned Kriegsmarine conference - of Radar Absorbing Material able to absorb 98 -99 % of the incoming radar energy in the 3 Ghz band (H2S).  It consist of several layers of di-electric material embedded in a foam like material.

 
     
  Returning to the KTB note above, pictures of radar reflectors have been found in the Esbjerg area and the foundations are still there.  What is inexplicable is their location on land.  Reflectors increasing an echo in the Hansted (Hanstholm) area makes no sense.  There are no lakes in the area to camouflage, and the prevailing wind and consequent sea state, makes mooring at sea an impossibility.  
         
  In the beginning of AUG 1944 a Danish agent reports that he has gained access to Verteidigungsbereich Hansted one of the heavyliest fortified and armed place in Denmark.  He observes that 350 "devices" have been positioned in the area.  He manages to engage in conversation with a German Feldwebel (?) who informs him that the "devices" are intended for the launch of a rocket-bomb called V 10.  The "devices" are positioned as shown on the below map and have the design shown on the right, which has little or no bearing on the launch of rockets.  He further reports that the screens/plates in the construction are made of a asbestos like materiel AND HE OBTAINS A SAMPLE.  
         
 

 

 
 

The map from the agents report.

 

Annex describing the screens, note the striking resemblance with the radar reflectors in part 2

 
         
 

In the post war reporting there is scarcely any mention of these screens.  The US Seacoast Artillery Evaluation Board makes no mention of these objects, and the equivalent Danish commissions only makes a brief note, which is a quote from the above report.  The RAF Disarmament Squadron, which was responsible for recording, exploitation and disposal of German radars in Denmark - Luftwaffe and Kriegsmarine alike - does not mention these devices in their report.  So the first question was: Was the entire report a hoax ?  This would not be unprecedented in the History of Intelligence.  If these objects could be related to an (unusual) weapon surely one of the artillery commissions would have reported it, if it was radar related the RAF should have reported it.  And if indeed they were something special, there ought to be photos.  There were no close-ups with these objects as the motive. A careful reexamination of existing photos, however, turned up the shots below.

 
         
 

 

 
 

 
  Same map as used by the agent indicating the areas, where "devices" were located.  
         
         
 

 

 
 

Photo from area A.  2 (3)? "devices" can just be discerned.  The rubbish on the beach may also be parts.

 

Photo from area B.  Several white dots can be seen.  The agent reported about 30 devices in A & B together, the rest in C.

 
         
 

 

 
 

Enlargement of the photo above.  The right part of a "device", the left is lying on the ground.  Compare with (retouched) photo opposite.

     
         
  The question is: What were the "devices" ?  
  1.  They have the shape of German radar reflectors.  
     
  2.  In JAN 1944 the Kriegsmarine reports that camouflage against the H2S is in progress in the Hansted area.  Active reflectors which needs to be of metal have not been found or reported/photographed and have no practical application in the area.  
     
  3.  The agent reports that the "devices" consist of an asbestos (Styrofoam ?) material.  
     
  I admit that the above only is circumstantial evidence, but I think that my case is strong enough for the opposition to agree on a settlement.  It is my working hypothesis that the "devices" were objects intended to reduce the radar return form the "treated" areas.  Either through diffraction or through use of the radar absorbing material illustrated in part 2.  
         
   
  Artist's impression of what the Hansted area might look like on a H2S, with the receiver gain turned down to reduce sea clutter.  The RAF navigator is looking for a good, clean return from the coastline.  It would be natural to turn the gain down, but this would also result in no return from the areas with the devices.  He would not get the predicted return, so was this the waypoint he was looking for?  
         
 

 

 
 

H2S scope picture of the Müritzsee.

 

The navigator's map of the same area.

 
     
     
 

The above 2 picture illustrates clearly - I think - the difficulties facing the navigator in the interpretation the scope display in a "coastal area".  There are lakes and inlets, which are not displayed because the gain is a little too high. Imagine what the picture would look like if there were active and passive reflectors in the area.

 
         
         
  Again I would be grateful for help.  First of all to confirm my theory or a positive identification of the "devices".  
         
         
         
   
         
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