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         The Role of Barrage Balloons in the Ghost Fleet on D-Day

The British were desperate to fool the Germans in the build up to D-Day. On the night of the 5th June and into the early hours of the 6th June 

1944, a massive deception was devised. It was designed to reinforce the belief by the Germans that an attack would take place well East of  

Normandy .

Operation BODYGUARD had as parts of the plan, Operation "GLIMMER" and "TAXABLE", played on the German belief, amplified by Allied deception 

efforts over the preceding months, that the main invasion force would land in the Calais region. The intension was to simulate that a large 

invasion fleet was heading for Cap d'Antifer by TAXABLE and Pas-de-Calais by GLIMMER.

Hitler's West Wall had radar stations located about every 10 miles from Ostend to Cherbourg , and on average three radar stations at each point, 

it was a priority that as many of these had to be put out of action. These were made up of Freya, Mammut and Wasserman early warning radars 

together with Seetakt ship search and fire control radars, small and giant Wuerzberg radars for fighter and flak control.

To maintain confusion, for every radar station attacked in Normandy , at least two others not in Normandy were attacked.

The Telecommunications Research Establishment (TRE) at Malvern developed a series of special ground direction finders called "Ping-Pong". These 

were spread out over western England and when triangulation a signal from a radar station were able to plot it to with 0.25 of a degree.

These radar stations were heavily defended and destruction fell to specialised ant-radar Spitfire and Typhoon squadrons of the 2nd Tactical Air 


Their missions began on 16th March 1944 when targets at Ostend were attacked.

Dr (Later Sir Richard) Cockburn began to plan a massive electronic spoof two enormous fleet of ghost ships. Instead of using a fleet of  really large 

ships they were told that every large vessel was needed and that they could only have a few small ships from which to launch their spoof.

The TRE worked out that they could produce a huge radar echo, that would look like a huge fleet at sea but using no really large vessels. What he 

needed to convince the Germans of was that a zone of radar reflectivity some 16 miles by 16 miles would convince them that a huge armada was 

sailing to them, while the real D-Day armada was sailing to Normandy .

This was achieved by using a number of aircraft dropping aluminium foil or window along carefully worked out tracks over the channel. TRE used 8 

aircraft in two waves of four flying abreast two miles apart with the second wave of four some 8 miles behind them. The aircraft flew in an oblong 8 

miles by 2, at 180 mph (3 miles per minute) and drop window at the rate of 12 bundles per minute meaning there was one bundle of window 

airborne every 440 yards.

Incredibly this produced a rate of passage on a radar screen of around 8 knots which was more in line with the passage of a fleet of large ships.

This part of the plan was code-named Operation "TAXABLE" and was to use eight Lancaster bombers from 617 Squadron and they were to fly 

along a course toward the East of Le Havre.

In addition to this there was Operation "GLIMMER", flown by six Stirlings from 218 Squadron heading on a course for Boulogne who were to carry 

out the same basic exercise as the Lancasters .

In May 1944 Cockburn trialled a dummy run using captured German Freya, Seetakt and Wuerzberg radars that had been installed on a part of the 

Scottish coast overlooking the Firth of Forth. In this dummy run British radar operators knew they were seeing a spoof but were impressed that it 

looked so real. Next the spoof was trialled using British radar operators at Farnborough Head in Yorkshire who had not been told it was a spoof. 

They were totally convinced that a huge fleet was at sea! If it worked that well on trail it should work well on D-Day.

  The one flaw was that it might be that the Germans would send out a reconnaissance plane to observe the size of the fleet.  The view was that if 

dozens of German radar operators were seeing a huge fleet on their screens and since all this took place during darkness, the German pilots would 

probably think they were looking in the wrong part of the channel, since something that big would be seen if the Germans were observing in the 

right part of the channel.          It was hoped it would act as a double bluff, with the German radar convinced and the German pilots thinking they 

were flying over the wrong part of the channel.

  Cockburn had been of the opinion that the false radar plots would be so convincing that any doubt expressed by a single reconnaissance plane 

would have been dismissed by the higher German command since there was an indisputable fact on the radar screen.

To add even more reality to the spoof radar plots, Special Task Force A was set up this comprised four high speed Harbour Defence Launches and 

fourteen smaller R.A.F. Pinnaces that were not needed for D-Day.

Each of the smaller launches towed a float and each one flew a specially equipped MkVI radar reflector balloons, code-named as a "Filbert" across 

the channel.

In addition, the air-sea rescue launches carried specially radar repeaters, called "Moonshine" repeaters. These were tuned to a specific radar 

frequency which was found on German maritime patrol aircraft. These repeaters retransmitted the German radar pulse and made the Germans 

believe they were seeing much more than was there.

The earlier MkVI reflector balloons had a radar reflector that was in a  collapsible steel frame 5 feet in diameter. The frame had polar stays at the 

polar joints and the equatorial stays were fitted round the centres of the frame of five wires , two of the wires had screws for adjusting.

The frame weighed some 18 lbs and was placed inside the balloon using the access slot and then sealed in.    

Each time the frame had to be serviced or the balloon deflated operators had to enter via the a ccess slot and remove the frame. The framed type  

had a suspension rigging of 3 legs, one 27 inches long and one 32 inches long. The two short joints were attached to the equatorial joints and the 

long one attached to the Polar joint. In addition, a 9-inch strop of No.3 line was fitted with a heart shaped thimble and clipped to the strop by a 

Buggins Clip. The anchorage rigging was made by making a 5-inch wire spreader from polar joint to polar joint. The lines are two of 27 inches and 

one of 32 inches long. The Bakelite ring was removed and replaced by the hearts shaped thimble with a 4-inch grommet strop. On the 4-inch strop 

were two Buggins clips that hooked on to the bungee cord in patches. The screen when installed was aligned at 57 degrees to the horizontal and 

secured with special locking pins.



An innovation was to make a frameless reflector. That had no metal frame and would be flexible, cheaper, lighter and could be rolled up with the 


The Royal Radar Establishment, (Later Royal Radar and Signals Establishment) worked on the development of all these Celanese products and their  use in radar deception.

Readers may well remember that any MKVI balloon with a green spot on it between the access slot and the inspection port was meant to let you    

know it had been modified to carry the 5 feet 6-inch radar screen. The balloons were often referred to as a green spot balloon.

The balloons had the reflectors placed internally but used a new form that had no frame. This new type of reflector did not need to be removed 

from the balloon before deflating and rolling up.

This new frameless reflector was twice the surface area of the framed version, weighed 9 lbs giving more lift to the balloon and once installed did 

not need to be removed and the balloon could be deflated and rolled up without having to remove the reflector thus saving time and effort.

The basic material used was a product called Celanese which was covered in copper wire.

Many of you (Particularly W.A.A.F's) will remember this material. It is a manmade fibre which aimed to replace silk during WWII when there was a 

shortage of silk. I have it on good authority that several W.A.A.F and W.R.N.S. serving at the time were given lengths of Celanese for making into 

slips etc.



                                                  It was used for glamorous gowns right into the late 1950's.

Task Force A left port in the evening of 5 June, bad seas which affected progress to all reach their meeting point on time. By 00:37 hours on 6 

June the lead boats were on schedule and had reached the muster point. Between 02:00 hours and 04:00 hours the ships operated radar and radio 

equipment as they headed toward a point 7 miles (11 km) off the enemy shore. They tied the "Filbert" balloons and the Moonshine reflectors to 

the floats and began a final part of their spoof. The balloons reproduced a “big ship” type of echo on the enemy radar screens. From there the task 

force simulated a landing attempt; by running fast to within 2 miles (3.2 km) of the beach before returning to the 7-mile marker under cover of 

smoke. The huge smokescreen was begun and they used loudspeakers to broadcast the sounds, squeaks, rattles and splashes that such a huge ghost 

fleet would have made when dropping anchor. The British then left hastily as they still had no idea if the Germans would have been fooled.

During this time only a small German response was observed including searchlights and intermittent gunfire. Shortly after 05:00 hours the 

operation ended and the task force laid mines in an effort to destroy any German craft that might come out to investigate, before heading toward 

Newhaven, reaching port by midday.

The enemy were fooled, a German logged report that "at 0300 hours a large number of landing craft and escorts neared the coast of Seine Bay 

between Caen and Carentan." and "It appears some 200 ships were involved". They also thought that 33 landing craft were at Bernieres and 44 at 

near the mouth of the Orne. One other report was that coastal observers had seen 6 large warships including battleships and 20 destroyers at a 

position 10 sea miles west of Le Havre !

The plan had worked far better than anyone had ever thought and led to considerable confusion for the enemy, a rush of German reinforcements 

to the wrong area and drew attention from the real D-Day landings.

Modern calculation indicate that balloons used in this deception could mimic the presence of a ship of several hundred tons.


   © Peter Garwood February 2024









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