Hi all, I am pleased to show you some of the pictures I took during my latest exploration.
Please enjoy these four pictures, and read the report down under.
Please also keep in mind that this is my first report, and that I'm not a native English speaker.
Thank you.
DISCLAIMER : All of these informations were gathered on the internet, and due to the nature of the site, might or might not be fully accurate.
DISCLAIMER : This text depicts dangerous situations (climbing of unsafe structures) do not attempt by yourself, you might get INJURED or even DIE, no picture is ever going to be worth taking the risks.
I] A bit of History :
Air 70 (aka RA70) is the name of the first dedicated communication network for the French Air Force (Armée de l'Air, aka AdA).
Up until the 60's, the AdA bases relied on the standard landline telephone system to communicate with each-other.
However, with civilian use growing, and lines being rather still limited in number, the phone network was quickly becoming saturated and thus would be unreliable in an emergency situation.
It was also noted that the telephone was an easy target for acts of sabotage. That's why it was decided to create a "web-like", autonomous and reliable communication network for the AdA.
It was used through decades up until the late nineties where the old and now obsolete system was no longer of use.
Most stations closed between 1999 and 2002.
II] A deeper dive into Air 70 ...
The Air 70 network was built around two "sub networks". The main one was baptised "Mercure" (from the roman god Mercure, messenger of the gods). The second sub-network was named "MX-622" (MX standing for Multiplex).
Mercure was a tropospheric transmission network operating in the 4.4 to 4.6GHz range. It used analog 1kW dual transmitters (on two dedicated parabolic antennas) and quad receivers (on two dedicated parabolic antennas) .
The RF equipement was built by CFTH (Compagnie Française Thomson-Houston) around Westinghouse licenced klystron, and the parabolic reflectors by TRT. It could be used to send and receive voice on 300 phone lines or data at a rate of 24kBits/s.
The MX-622 was built buy Thomson-CSF, and was an transitored version of the earlier MX-621. It operated in the 1.7 to 2.7GHz range (while it probably used parabolic antenna, there is no information on the size they used to be).
It was a "direct view" analog transmission network used to link close AdA bases to the nodes (and so to the other bases). It allowed for the use of up to 120 phone lines.
The station's 30 meters tall masts, wave guides and parabolic reflectors were built and installed by TRT.
Twenty-three stations were built almost everywhere on French territory, excepted in Britany.
Except a few stations, they were all built around the same design consisting of three buildings an two (sometimes three) masts.
The first building was the power distribution building. It housed high current & 400 volts main circuit breakers, as well as the emergency generator.
The second building was radio building. All the Mercure and MX622 equippement would be stored here.
The third building was the living quarters. Everything necessary for the dozen of men working on site.
If most of the twenty-three stations would act as simple relays or network nodes (part of the RTR : Réseau Temps Réel = Real Time Network), some had additional tasks, such as the RTD (Réseau Temps Différé = Delayed Network) or even RTT (Réseau Télésurveillance & Télésignalisation = Surveillance Network).
The RTR, as its name implies, is the real-time communication network.
The RTD served as the network's "voice-mail". Only four sites had formed this network. They used the "RAID" (Relai Automatique d'Information Digitale = Automatic Relay for Digital Information), a suite of specific equippement (the computers and the 1.2kBits/s and 2.4kBits/s modems), built by Alcatel. All four RAID systems while able to work as stand-alone, were connected to each other using highspeed links (no information on the nature of these).
The RTT had the goal of probing the Mercure network, constantly monitoring the bandwith used by each station. It could order any station to reroute data to another station if needed and would send commands to all twenty-three stations every ten seconds to make sure to keep the Mercure network as stable as possible.
III] About this station
This station was built during the early seventies and commissioned in 1978. It was the last station of the first "triangle". The first triangle were the first three stations comissionned, they were partly used to test the various equippements in real-life situations.
It was decomissioned around 2000, possibly 2002, and probably dismantled in until 2007 to 2010 (dates at which the parabolas are no longer hung on the tallest mast).
However, the main 20kV transformer still rumbles to this day, meaning it is connected to the grid (reason as to why remains unknown).
IV] Let's explore
It was late at night, I had taken the last train available as I could not go any sooner. When I arrived at the nearest train station, I had still a few hours of walk left to do, all alone. The first fourty minutes were easy, it was in a city, roads were well lit by the orange sodium-vapor lamps. But before I could even think about it, I was about to exist the city. A few meters forward and I was walking on a small unlit regional road, in the early hours of the morning, fully dressed in black, with a backpack and visible photo gear. It would have been easy for any local to understand my whereabouts had they seen me on the road.
I chose to duck in the tall grass by the road anytime I would spot a car coming my way. Some could say I was over-reacting, and to some extension I probably was, but I did not want to run the risk of getting spotted or even worse, hit by a car.
As cars drove by, the kilometers flew, and it was time for me to leave the road and walk through the fields, the last step before arriving on site.
All I could see were the stars, a few lights in the fields, the red light ontop of the windmills and vague shapes, were they trees or were they hills ? The noise of the trees cracking in the wind, and those of animals scared by my presence made for a very omnious ambiance. After a few scare, a suspect shape appeared far away. I took out my camera and took a long exposure shot (see images no°1 & 2). After waiting for my camera to capture the shots, I could see for myself : the three masts were right in front of me, I was close !
After three hours of walk I was finally at the gates. After I found my way in, the ambiance was even more omnious than ever, I could not see, but I could hear things, was it other explorers hiding because they had heard me ? Was it an animal ? Or was it simply the rain and the wind against the trees ? It sounded like murmurs, or someone trying to walk as softly as possible. I decided to back out of the site and wait outside for a bit, maybe the people would come out then.
After some time, the first lights of day began to lit up the sky and I decided to go back in, for real this time.
As I was walking in, through thick tree branches I found the most likely culprit for the noises I had heard on my first try : a small grey bunny.
I did get my revenge though, it got scared and hoped away when I shined my flashlight on him.
Just a few more meters through the branches, and there they were. The three masts, silently standing still, rust slowly creeping its way onto everything. How long do they have left before collapsing ? (see image no°3)
I began to explore, first was the power distribution building, the remains of the emergency generator could be seen here as well as some circuit breakers. The room adjacent to the engine hall had seen itself being converted by squatters into an improvised living room with mossy couches, its wall had been covered by grafitis. All the windows were broken, and most of its doors either opened or broken too. Not much was left to see, so I left to explore the rest.
In front of the other two buildings, located next to each other with one building rotated ninety degrees right, was a pile of unrecognisable things, burnt bits of wood, broken glass, pieces of plastic, littering the ground. It was hard to go through without making too much noise.
I entered the second building, the living quarters as I wanted to keep the best at the end. Not much was to see here either, more broken and burnt objects. I quickly explored each of the few rooms and exited the building.
The third and last building was the radio building, the one I was the most eager to visit.
Sadly but as I expected, everything of value had been dismantled and taken away as the personnel left, or was broken and stolen by previous explorers.
Only reminder of a distant past were a few breaker boards and what I identified as I commutator of some sort (see image no°4).
After having captured my photo, I walked my way through broken glass to the main room, where all the radio equippement would have been sitting until twenty years ago. Not much was left here, only a few big metalic cabinets filled with electro-mechanic parts weirdly hanging above the floor.
The doors of said cabinets still had most of their indicator lights and associated descriptions. You could read on one door, above all the indicators "MERCURE, demi terminaux principaux" and "MERCURE, demi terminaux secondaires" (MERCURE, main half terminals and MERCURE, secondary half terminals), and the name of the other stations this one was connected to.
I wondered for a bit as for why was the ground so low compared to the other rooms and why did the cabinet hung so high.
The reason was simply that the personnel must have removed the fake floor used to mask cables when dismantling the equippement.
I headed outside to a small court, where nature had taken back its right with full power, I could see a few parabolic antennas filled with moss and water laying on the ground, what were these used for ?
I began to explore around, taking some pictures on my way to the masts, "Which one should I climb first ?" was I thinking. I chose the tallest and most recent of three.
It did not hold any antenna anymore, perhaps the parabolas I had found minutes earlier were once hung up there ?
I started to climb, I could feel the mast swinging from side to side from being blown away by the wind.
After a few meters, I was beyond the treetops and I could finally feel the wind blowing in my face.
Roughly thirty meters left to climb, with the worry of being spotted by cars passing by.
Only when I was at the top of the mast could I fully appreciate the view of the site, and the fields around it.
The Sun was slowly starting to show itself, and I could see the first people going to work in the villages not far away, so I decided to get back down before getting caught, afterall, I had still two other masts to climb !
Going up was not much harder than the first one, but the integrity of the structure was much more concerning. The fences of the platforms were severly rusted and could not hold any weight.
I made sure to plan every step I had to make beforehand, as falling from twenty meters would not be very forgiving.
It was fascinating for me, I was sitting on a mast, on a former military site, right next to twelve meters wide parabolas.
I snapped some pictures, then some more and decided to head back down.
I had already visited all the buildings, but starting to be hungry and still having some time before having to leave to catch my train, I decided to find a way on the ceiling of the power distribution building.
It was a rather easy feat, the ladder was easily accessible from outside, I just had to make sure not to get scratched by the brambles.
Once ontop of the building, I took out and ate my sandwhich, admired the sun rising, took a few pictures before having to leave the site for "good".
I swore myself to come back on day...
K.33 2024
Please enjoy these four pictures, and read the report down under.
Please also keep in mind that this is my first report, and that I'm not a native English speaker.
Thank you.
DISCLAIMER : All of these informations were gathered on the internet, and due to the nature of the site, might or might not be fully accurate.
DISCLAIMER : This text depicts dangerous situations (climbing of unsafe structures) do not attempt by yourself, you might get INJURED or even DIE, no picture is ever going to be worth taking the risks.
I] A bit of History :
Air 70 (aka RA70) is the name of the first dedicated communication network for the French Air Force (Armée de l'Air, aka AdA).
Up until the 60's, the AdA bases relied on the standard landline telephone system to communicate with each-other.
However, with civilian use growing, and lines being rather still limited in number, the phone network was quickly becoming saturated and thus would be unreliable in an emergency situation.
It was also noted that the telephone was an easy target for acts of sabotage. That's why it was decided to create a "web-like", autonomous and reliable communication network for the AdA.
It was used through decades up until the late nineties where the old and now obsolete system was no longer of use.
Most stations closed between 1999 and 2002.
II] A deeper dive into Air 70 ...
The Air 70 network was built around two "sub networks". The main one was baptised "Mercure" (from the roman god Mercure, messenger of the gods). The second sub-network was named "MX-622" (MX standing for Multiplex).
Mercure was a tropospheric transmission network operating in the 4.4 to 4.6GHz range. It used analog 1kW dual transmitters (on two dedicated parabolic antennas) and quad receivers (on two dedicated parabolic antennas) .
The RF equipement was built by CFTH (Compagnie Française Thomson-Houston) around Westinghouse licenced klystron, and the parabolic reflectors by TRT. It could be used to send and receive voice on 300 phone lines or data at a rate of 24kBits/s.
The MX-622 was built buy Thomson-CSF, and was an transitored version of the earlier MX-621. It operated in the 1.7 to 2.7GHz range (while it probably used parabolic antenna, there is no information on the size they used to be).
It was a "direct view" analog transmission network used to link close AdA bases to the nodes (and so to the other bases). It allowed for the use of up to 120 phone lines.
The station's 30 meters tall masts, wave guides and parabolic reflectors were built and installed by TRT.
Twenty-three stations were built almost everywhere on French territory, excepted in Britany.
Except a few stations, they were all built around the same design consisting of three buildings an two (sometimes three) masts.
The first building was the power distribution building. It housed high current & 400 volts main circuit breakers, as well as the emergency generator.
The second building was radio building. All the Mercure and MX622 equippement would be stored here.
The third building was the living quarters. Everything necessary for the dozen of men working on site.
If most of the twenty-three stations would act as simple relays or network nodes (part of the RTR : Réseau Temps Réel = Real Time Network), some had additional tasks, such as the RTD (Réseau Temps Différé = Delayed Network) or even RTT (Réseau Télésurveillance & Télésignalisation = Surveillance Network).
The RTR, as its name implies, is the real-time communication network.
The RTD served as the network's "voice-mail". Only four sites had formed this network. They used the "RAID" (Relai Automatique d'Information Digitale = Automatic Relay for Digital Information), a suite of specific equippement (the computers and the 1.2kBits/s and 2.4kBits/s modems), built by Alcatel. All four RAID systems while able to work as stand-alone, were connected to each other using highspeed links (no information on the nature of these).
The RTT had the goal of probing the Mercure network, constantly monitoring the bandwith used by each station. It could order any station to reroute data to another station if needed and would send commands to all twenty-three stations every ten seconds to make sure to keep the Mercure network as stable as possible.
III] About this station
This station was built during the early seventies and commissioned in 1978. It was the last station of the first "triangle". The first triangle were the first three stations comissionned, they were partly used to test the various equippements in real-life situations.
It was decomissioned around 2000, possibly 2002, and probably dismantled in until 2007 to 2010 (dates at which the parabolas are no longer hung on the tallest mast).
However, the main 20kV transformer still rumbles to this day, meaning it is connected to the grid (reason as to why remains unknown).
IV] Let's explore
It was late at night, I had taken the last train available as I could not go any sooner. When I arrived at the nearest train station, I had still a few hours of walk left to do, all alone. The first fourty minutes were easy, it was in a city, roads were well lit by the orange sodium-vapor lamps. But before I could even think about it, I was about to exist the city. A few meters forward and I was walking on a small unlit regional road, in the early hours of the morning, fully dressed in black, with a backpack and visible photo gear. It would have been easy for any local to understand my whereabouts had they seen me on the road.
I chose to duck in the tall grass by the road anytime I would spot a car coming my way. Some could say I was over-reacting, and to some extension I probably was, but I did not want to run the risk of getting spotted or even worse, hit by a car.
As cars drove by, the kilometers flew, and it was time for me to leave the road and walk through the fields, the last step before arriving on site.
All I could see were the stars, a few lights in the fields, the red light ontop of the windmills and vague shapes, were they trees or were they hills ? The noise of the trees cracking in the wind, and those of animals scared by my presence made for a very omnious ambiance. After a few scare, a suspect shape appeared far away. I took out my camera and took a long exposure shot (see images no°1 & 2). After waiting for my camera to capture the shots, I could see for myself : the three masts were right in front of me, I was close !
After three hours of walk I was finally at the gates. After I found my way in, the ambiance was even more omnious than ever, I could not see, but I could hear things, was it other explorers hiding because they had heard me ? Was it an animal ? Or was it simply the rain and the wind against the trees ? It sounded like murmurs, or someone trying to walk as softly as possible. I decided to back out of the site and wait outside for a bit, maybe the people would come out then.
After some time, the first lights of day began to lit up the sky and I decided to go back in, for real this time.
As I was walking in, through thick tree branches I found the most likely culprit for the noises I had heard on my first try : a small grey bunny.
I did get my revenge though, it got scared and hoped away when I shined my flashlight on him.
Just a few more meters through the branches, and there they were. The three masts, silently standing still, rust slowly creeping its way onto everything. How long do they have left before collapsing ? (see image no°3)
I began to explore, first was the power distribution building, the remains of the emergency generator could be seen here as well as some circuit breakers. The room adjacent to the engine hall had seen itself being converted by squatters into an improvised living room with mossy couches, its wall had been covered by grafitis. All the windows were broken, and most of its doors either opened or broken too. Not much was left to see, so I left to explore the rest.
In front of the other two buildings, located next to each other with one building rotated ninety degrees right, was a pile of unrecognisable things, burnt bits of wood, broken glass, pieces of plastic, littering the ground. It was hard to go through without making too much noise.
I entered the second building, the living quarters as I wanted to keep the best at the end. Not much was to see here either, more broken and burnt objects. I quickly explored each of the few rooms and exited the building.
The third and last building was the radio building, the one I was the most eager to visit.
Sadly but as I expected, everything of value had been dismantled and taken away as the personnel left, or was broken and stolen by previous explorers.
Only reminder of a distant past were a few breaker boards and what I identified as I commutator of some sort (see image no°4).
After having captured my photo, I walked my way through broken glass to the main room, where all the radio equippement would have been sitting until twenty years ago. Not much was left here, only a few big metalic cabinets filled with electro-mechanic parts weirdly hanging above the floor.
The doors of said cabinets still had most of their indicator lights and associated descriptions. You could read on one door, above all the indicators "MERCURE, demi terminaux principaux" and "MERCURE, demi terminaux secondaires" (MERCURE, main half terminals and MERCURE, secondary half terminals), and the name of the other stations this one was connected to.
I wondered for a bit as for why was the ground so low compared to the other rooms and why did the cabinet hung so high.
The reason was simply that the personnel must have removed the fake floor used to mask cables when dismantling the equippement.
I headed outside to a small court, where nature had taken back its right with full power, I could see a few parabolic antennas filled with moss and water laying on the ground, what were these used for ?
I began to explore around, taking some pictures on my way to the masts, "Which one should I climb first ?" was I thinking. I chose the tallest and most recent of three.
It did not hold any antenna anymore, perhaps the parabolas I had found minutes earlier were once hung up there ?
I started to climb, I could feel the mast swinging from side to side from being blown away by the wind.
After a few meters, I was beyond the treetops and I could finally feel the wind blowing in my face.
Roughly thirty meters left to climb, with the worry of being spotted by cars passing by.
Only when I was at the top of the mast could I fully appreciate the view of the site, and the fields around it.
The Sun was slowly starting to show itself, and I could see the first people going to work in the villages not far away, so I decided to get back down before getting caught, afterall, I had still two other masts to climb !
Going up was not much harder than the first one, but the integrity of the structure was much more concerning. The fences of the platforms were severly rusted and could not hold any weight.
I made sure to plan every step I had to make beforehand, as falling from twenty meters would not be very forgiving.
It was fascinating for me, I was sitting on a mast, on a former military site, right next to twelve meters wide parabolas.
I snapped some pictures, then some more and decided to head back down.
I had already visited all the buildings, but starting to be hungry and still having some time before having to leave to catch my train, I decided to find a way on the ceiling of the power distribution building.
It was a rather easy feat, the ladder was easily accessible from outside, I just had to make sure not to get scratched by the brambles.
Once ontop of the building, I took out and ate my sandwhich, admired the sun rising, took a few pictures before having to leave the site for "good".
I swore myself to come back on day...
K.33 2024
