FuSan Dora, Saint Martin aux Buneaux

RADAR · StP. Groupe St-Valéry en Caux · AOK 15 Haute-Normandie · France

FuSan Dora, Saint Martin aux Buneaux

Radio-navigation station. coded Y4 Dora Saint Martin aux Buneaux,

FuSan Dora, Saint Martin aux Buneaux

FuSan Dora, Saint Martin aux Buneaux

The RAF target map dated 36 June 1942. Showing all the Flak and transmitter positions.

Luftwaffe station FuSan Dora (German Navigation Beam Station).
Y4 "Dora" - Stn-Martin-aux-Buneaux (Haute-Normandie).
3 x Flakstellung.
1 x Peiler Heinrich.
3 x Y.Geräte Fridolin.
5 x Machinenstand.
1 x Feldm.
2 x Unterstand.
3 x 2cm Flack 30. (Maybe more?)

Basically the system functioned as follows:
The Strahlbake was trained over the target, the bomber pilot navigated to stay in the beam, the E-Mess Gerät measured the distance, and various impulses were transmitted to enable the bomber crew to use the X-Uhr for automatic bomb release.

Early 1940 there were 3 Y-stations in Ostfriesland, the Ruhrgebiet and the Schwarzwald, covering the West-German border, plus a training-station near Rechlin. III/KG26 started training on Y-Gerät end August 1940 so the system would not have been used in the French campaign.
Summer 1940 the German Y-multibeam-stations were transferred to the French coast: Anton, Berta and Cicero. Y-attacks on Britain started September 1940 until July 1941 when III/KG 26 was directed to the Russian front, putting the Y-system unused into the cupboard.
In February 1942 a new pathfinder unit was created (ELK 100 => ELK XY =>ELK 17) to give new life to the Y-Verfahren (Kampf). According to Trenkle, this is the period that Anton was reequipped and Dora and Gustav were newly built to support or supersede Berta and Cicero; all three stations with improved Y-dualbeam-beacons. Those three stations operated until August 1944, when taken by Allied forces.
Meanwhile, new stations near Morlaix and Aumale were hardly or not used for some reason or another (Aumale was not ready beyond testing, but why not using the Morlaix Y-station is another puzzle).

It clearly shows the evolution of the Y-stations in France and therefore the bunkers built in them. Anton was a 1940-site, modernized in 1942; hence the different types of Y-line-bunkers. Dora and Gustav were new sites built in 1942, which explains the similarity of their bunkers.
Axishistory forum.

FuSan Dora, Saint Martin aux Buneaux

The RAF plan showing at least three Flak positions and the targets.

FuSan Dora, Saint Martin aux Buneaux

These documents were produced by Central Interpretation Unit (C.I.U.).

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle East side.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle North side.

Air Doc Target V/16

FuSan Dora, Saint Martin aux Buneaux

Rad Nav X system map of Britain and I have added D Dora Y system, the red dot next to Fécamp. This is the original 1940 X system map. Radio Air Nav website a very extensive website on this subject. Thank you to Frank Dörenberg for his help.

Air Doc Target V/16

FuSan Dora, Saint Martin aux Buneaux

A magazine article showing how it worked. This is a dual beam beacon. or Y-Zwelstrahlbake. From La Tecnolgia Radar Tedesca.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle (Vf Antenna). North side.

FuSan Dora, Saint Martin aux Buneaux

Captioned as Wotan radar, it was actually a radio navigation and not radar. This is a picture I have found to show what it may have looked like.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle West side, not absolutely no damage from Allied plane attacks?

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle North side. This is the entrance and also steps up to the roof.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle Entrance.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle Entrance. Fittings to allow cabling into the bunker.

FuSan Dora

FA Sendstelle Wall brackets.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle First room.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle Second small room.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle Main room. What fitted on the plinth, I have no idea. Why the slot and also another in ts side.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle Main room.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle Main room. This inner wall is brick.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle Way out and there was a door fitted at some time, I could not find hinges, but the door catch is still there.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle Camouflage in the entrance.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle Way out.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle Screw picket for the barbed wire defence on the floor.

Barbed wire entanglement around the bunker.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle Steel steps up to the roof, still in good condition.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle An oblong piece of metal, not part of the steel reinforcement. There are about six (tie downs) and may have been used to hold the radio array in high winds.

FuSan Dora, Saint Martin aux Buneaux

Roof

18 March 2024

FuSan Dora, Saint Martin aux Buneaux

FA Unterstand Either a control bunker or a living bunker, I could not get anywhere near it to look inside. Control; may have been some semi sunk wooden huts with camouflage nets. These FA Unterstands may have been ready rooms/barracks for the Luftwaffe troops running the radio guidance.

FuSan Dora, Saint Martin aux Buneaux

FA Unterstand Entrance on the left, grass on the roof as camouflage.

FuSan Dora, Saint Martin aux Buneaux

FA Generator It looks un finished generator house, made in Formstien breeze block and no reinforcement and no roof.

FuSan Dora, Saint Martin aux Buneaux

FA Generator

FuSan Dora, Saint Martin aux Buneaux

FA Unterstand Another I managed to seen it but could not photograph it as its too close somebody's house.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle Different style to the first one.

FuSan Dora, Saint Martin aux Buneaux

Betonformstein construction.

Betonformstein

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle East side.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle Roof.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle Protected entrance passage.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle An attack by a fighter/bomber on one of the transmitters, I didn't find any evidence of machine gun or cannon damage on the three buildings I looked at??.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle Entrance passage showing the tiled floor.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle Entrance.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle Main room showing a wooden frame on the wall.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle Another shelf bracket and ventilation above the door.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle Main room with a slot leading out into the roof, possibly a drive shaft to the array on the roof?

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle Outside a set of steel steps up to the roof.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle The last step to hold on to to get onto the roof.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle The roof.

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle The Google image from Relikte showing the western side with the first of two flak positions. This one I should have visited, but ran out of time.

FuSan Dora, Saint Martin aux Buneaux

Air Doc Target V/16 showing up to three Flak positions and all light Flak, 2cm Flak 30.Possibly six guns.

Air Doc Target V/16

FuSan Dora, Saint Martin aux Buneaux

FA Sendstelle SHM picture taken around 1945 by the French military. 400meters to the east were these two towers and the farm was the camp for the Luftwaffe crew.