A self-guided French bomb in 1939.

[klem]

In the magazine "Décollage" N°64 of 06.19.1947- p 12 .a reader Mr. Alphonse Martin informed the editorial staff of the magazine that he realized in 1939 the plans of a self-guided bomb. It is a gliding bomb launched by plane and equipped with an automatic piloting device which directs it towards the target. The device consists of the body of the bomb equipped with cruciform wings at the front and at the back. At the front, the bomb is equipped with a combination of five photo-voltaic cells mounted at the front . (see the details attached in the article) to actuate the control surfaces via servo-motors. The cell placed at the end of a wing known as cell of compensation acts on the control surfaces. The bomb once taken of the selected point at a certain distance, one of these cells is excited by the infra-red beam of the target via its electro-mechanical device, rectifies its trajectory by blocking the control surfaces in their position.

 

[hesham]

Maybe it belonged to de Monge of 1940;

https://www.secretprojects.co.uk/threads/louis-de-monge-aircraft-list.32655/#post-369777

 

[klem]

Maybe it belonged to de Monge of 1940;

https://www.secretprojects.co.uk/threads/louis-de-monge-aircraft-list.32655/#post-369777

No, it is a certain Alphonse Martin. The question is that his work was subject to registration of patents or not.

 

[Pioneer]

Fascinating find and thank you klem!!

Regards
Pioneer

 

[Dilandu]

!!! Fascinating! Could you please give any more data? Early guided weapons is my sphere of interest.

 

[Archibald]

Imagine if we had such weapons to anihilate the bridges and poontoons at Sedan and elsewhere... better than sending 71 Battles to their death by horrible attrition.
But 1930's France was an hopeless mess.

 

[Dilandu]

Imagine if we had such weapons to anihilate the bridges and poontoons at Sedan and elsewhere... better than sending 71 Battles to their death by horrible attrition.

It's infrared-guided bomb. It would not work against targets without bright infrared signature. It's more about hitting industrial plants at night (imagine if you could raid German industry, and make every bomb hit a factory building...)

For destroying bridges, I say the simple radio-controlled gravity bomb - a USAAF's VB-1 AZON analogue - would be much more practical. French radio industry could easily mass-produce a simple guidance kit for existing bombs.

If you want something that could home on bridge... Well, I'd say that the best idea would be optical-contrast bomb. I.e. using photocells working in visual light spectrum to home on a dark spot (bridge) on the reflective background of water. WW2-era photocells were quite sensitive, capable of detecting 0,05% of illumination difference.

 

[Archibald]

I see. Interesting. Do you think that a Panzer engine could make a good enough target ? one stuck in a big jam, waiting to cross a poontoon bridge. The engine should overheat and gets an interesting IR signature...

 

[Dilandu]

Do you think that a Panzer engine could make a good enough target ?

Doubt that. USAAF WW2-era infrared bombs - the VB-6 "Felix"- were tested on building-size targets, and generally fell within several dozen meters from aiming point.

More advanced Navy's infrared bomb ASM-N-4 "Dove" demonstrated better results, but still the average was 15 meters from the center of target. Good enough against ships - "Dove" was designed as anti-ship weapon - but not against tanks.

Both those bombs were supposed to hit rather large, self-heating targets (industrial buildings and warships), and weren't exactly suited for tracking something as small as individual tank engine. I really doubt that WW2 technology could create infrared-homing weapon, capable of reliably tracking the individual tank from significant distance. Maybe in favorable conditions - on snow, for example.

 

[Temistocle]

Maybe related to this:

Optical distance detecting devices
US patent filed in 1956, granted in 1969...

The same patent for Switzerland:
Dispositif télémétrique optique
1956 --> 1960

And Canada:
OPTICAL DISTANCE DETECTING DEVICES
Granted in 1961

 

[klem]

Maybe related to this:

Optical distance detecting devices
US patent filed in 1956, granted in 1969...

The same patent for Switzerland:
Dispositif télémétrique optique
1956 --> 1960

And Canada:
OPTICAL DISTANCE DETECTING DEVICES
Granted in 1961

Thanks Témistocle for these very interesting patent information concerning Alphonse Martin because the article of the Revue Décollage did not mention any other indication.that said these patents published after the war are directly related to the device installed on his project of self-guided bomb.