The Night the Resistance Destroyed Radio-Paris’s Main Antennas at Allouis

On the night of May 9 10, 1942, at Allouis in the Cher department, two explosions brought down part of one of France’s most powerful radio installations. At the other end of the chain, Radio-Paris, a mouthpiece for collaborationist propaganda and an instrument of German influence, lost its long-wave transmitter.

The operation, known as Operation Pilchard, was, according to historian Olivier Wieviorka, one of the few large-scale sabotage missions the BCRA (the Free French intelligence service) managed to carry out that year. Three men Henri Clastère, Paul Bodhaine, and Maxime Gaudin had been parachuted into the Cher region a few days earlier. Their mission was to strike the Allouis transmitter, which was used by Radio-Paris and also by the Germans to jam BBC broadcasts.

Several pieces of evidence the Radio-Paris schedules, frequency changes, the first dispatches from London, and above all the testimony of Alexandre Bézie, director of the transmitting center make it possible to reconstruct, almost minute by minute, the night when the North and West pylons came crashing down.

Radio-Paris, a key instrument of German propaganda

At the beginning of 1942, Radio-Paris occupied a prominent place in the French broadcasting landscape under German occupation. It broadcast in French and operated under the German propaganda services. Its programs were not transmitted on a single frequency. [Note: this Radio-Paris had absolutely nothing to do with Radio Paris, the national station that existed before the Occupation.]

In mid-February, a notice published in the press gave the station’s new schedule : “At 7 a.m., broadcasting begins; at 9:15 a.m., it ends. Broadcasting resumes at 11:30 a.m. and continues until 10:15 p.m. without interruption, on the following wavelengths: 312.80 m, 288 m, 274 m, 255 m and 1,648 m. From 8:15 p.m., Radio-Paris will broadcast a program of varied music on 1,648 m until 10 p.m. From 10 to 10:15 p.m., the final news bulletin will be broadcast on 312.80 and 1,619 m. Wavelengths and frequencies: 312.80 m, 950 kc; 288 m, 1,040 kc; 274 m, 1,095 kc; 255 m, 1,176 kc; 1,648 m, 182 kc.“

The choice of the 1,648-meter wavelength, or approximately 182 kHz, was crucial. It provided much wider coverage than medium waves and made the Allouis transmitter a particularly important asset in the war of the airwaves.

This arrangement changed rapidly. By mid-April, the Allouis long-wave transmitter was still in use until 10:15 p.m., while the 312.8-meter frequency, formerly used by Poste Parisien, took over. From 10:45 p.m. until 1 a.m., broadcasting continued exclusively on 312.8 meters. This technical setup largely explains what happened after the sabotage. Bringing down the long-wave antenna did not mean silencing Radio-Paris altogether.

Allouis : four 250-meter pylons

The Allouis transmitting center was far more than a simple antenna. Alexandre Bézie’s testimony, as director of the center, provides a detailed description in the French police investigation report preserved in the Cher departmental archives.

The four metal pylons stood 250 meters high. They had triangular cross-sections approximately three meters wide and were held in place by metal guy wires attached to the pylons every forty meters. The furthest anchor points were about 160 meters from the base.

The four pylons were connected to the building by an elaborate overhead structure. Cross-members linked the pylons diagonally in pairs, while their central sections were insulated to form four lines running from the tops of the pylons toward the center. Four down-leads then ran to the building.

In other words, the saboteurs did not necessarily have to enter the building or destroy the transmitters themselves. They only had to attack the structure supporting the antenna. And that is precisely what happened.

1:25 a.m. : The first explosion

The night of May 9-10 was particularly favorable for a clandestine operation. Bézie was at home in the house south of the main building. He described the weather as very overcast, with wind, intermittent rain, and above all a very dark night.

At 1:25 a.m., he heard the first explosion. It sounded muffled. At first, he thought it had come from the transformer near the entrance to the center, beside the road from Vierzon to Bourges. He even considered the possibility that it had been caused by a short circuit.

Then came a second explosion. “About a quarter of an hour later, I heard another detonation, identical to the first, followed, it seemed to me, by a cry.” This time, it was clear that something was wrong.

Bézie immediately telephoned the station staff. M. Dufron, a technical-service inspector, confirmed that an incident had occurred. It was after the second explosion that the station stopped operating or, more precisely, that a serious malfunction was detected. The director then suspected the antenna.

A breakdown that wasn’t a breakdown

Dufron went out into the grounds with M. Rost, a member of the German service staff. The initial inspection did not reveal exactly what had happened. The technicians did notice, however, that wires were tangled above the building, where the feeder wires came down. In the darkness, they could not immediately determine whether the cables had actually fallen.

Bézie then made a practical decision: the transmitter had to be shut down. Then the noises began again. “Again, the same noises a detonation and a whistling sound.” This time, Bézie thought he understood what was happening: a second wire might have fallen after the first broke, upsetting the balance of the structure. It was only at daybreak that the full extent of the damage became clear.

At around 5 a.m., Dufron came to tell the director that two pylons had fallen: the North and West pylons. His testimony is particularly valuable because it captures not only the damage but also the uncertainty of those first few hours. Bézie saw neither intruders nor any suspicious device inside the buildings. He even accompanied M. Schliemann into the outbuildings, but found nothing unusual. The investigation was then taken over by the German authorities.

The director was unequivocal : “I do not know who carried out the attack“. He added that he had no particular suspicions about anyone who might have been in the area.

Allouis was also the BBC’s largest jammer

To understand the strategic importance of the operation, it is important to remember that the Allouis transmitter did more than carry a radio program. Radio-Paris was certainly a key component of the occupier’s radio propaganda, but the installations were also used to jam BBC broadcasts transmitted on 1,500 meters from Daventry.

Destroying the antenna therefore had an impact far beyond the simple interruption of a propaganda station. Operation Pilchard is documented as a BCRA mission carried out with the assistance of British services. Henri Clastère, Paul Bodhaine, and Maxime Gaudin had been parachuted into the region during the night of May 5-6 to attack the transmitter. A contemporary British source described the event as the destruction by dynamite of the Radio-Paris pylons at Allouis.

The term blasting is supported by historical accounts and contemporary foreign sources, although the French technical testimony is more cautious about the precise method used.

Radio-Paris does not disappear

The radio response was immediate, but it also revealed the structure of the network. On May 11, a Reuters dispatch announced : “Radio-Paris (long wave) falls silent“. The dispatch stated that the long-wave transmitter had not broadcast since Saturday evening, May 9, after completing its program at the usual time. It immediately added : “Broadcasts on the other wavelengths took place normally“.

Rumors were circulating in London that an explosion had destroyed the antenna used by Radio-Paris for its long-wave broadcasts. Reuters reported that, according to these rumors, the explosion had been caused by sabotage. The wording was cautious : at that point, the information had not yet been officially confirmed in the foreign press.

The Lille relay and makeshift frequencies

The following days showed how the propaganda station adapted to the destruction of an essential piece of infrastructure. Radio-Paris announced an extension of its broadcasts until 2 a.m. from Sunday, May 24 onward. However, listeners now had to tune in on the 312.8-meter medium-wave frequency rather than the Allouis long-wave frequency.

By the end of the month, Lille was relaying part of the program: Radio-Paris was scheduled from 7 to 9:15 a.m. and from 11:30 a.m. to 10:15 p.m. on 255, 288, 274 and 312.8 meters, while the 10:15 p.m. to 2 a.m. slot was broadcast on 312.8 meters.

The broadcasting network had therefore been reorganized around the transmitters that remained available. On June 5, a communiqué addressed to listeners in southwestern France acknowledged the difficulties : “As Radio-Paris broadcasts on the Poste Parisien wavelength cannot be received clearly because of modifications, the work will be completed on Saturday, so that the southwestern region will once again have normal broadcasts from Sunday.”

The administrative wording concealed the reality. The destruction of Allouis had forced Radio-Paris to reorganize its coverage. Historians estimate that restoring the antenna took approximately twelve days. Olivier Wieviorka notes that the operation also interrupted German jamming during this period, allowing French listeners to receive British broadcasts more clearly.

The significance of Operation Pilchard lies precisely in this technical dimension. The aim was not to silence Radio-Paris permanently. The station had other wavelengths and other infrastructure. But the Resistance struck the hardest link to replace: a huge antenna supported by four 250-meter pylons. The sabotage transformed a national broadcasting station into a network forced to rely on relay transmitters and makeshift frequencies.

The Resistance strikes again

The following year, in May 1943, the Resistance attacked Radio-Paris again, this time by cutting the cable linking the studios on the Champs-Élysées to the Allouis transmitting center. Reuters reported that on Sunday, May 2, 1943, at 8:10 p.m. British time, Radio-Paris had fallen silent.

From May 23 onward, the press reported that the 1,648-meter Allouis long-wave frequency was now being used by the new German station Deutsche Europasender West, which broadcast, among other things, in the languages of the occupied countries of Western Europe. Radio-Paris would have to rely on medium waves until the liberation of the capital.