• Hi Guest! Forum rules have been updated. All users please read here.

Yehudi Lights

XB-35

ACCESS: Confidential
Joined
Sep 29, 2006
Messages
65
Reaction score
4
Hi All,

I'm looking for photographs (and technical drawings) of a Grumman Avenger (and also other aircraft) equipped with these lights (in a concealment experiment against U-boats).

There's an article about this project in an old issue of model aircraft monthly, but no photographs.

According this article, a B-24 Liberator has been also used in these experiments (and on a website article, post-war, a F-4 Phantom with the project name "Compass Ghost")

Does anyone has infos about these secret experiments ?

Thanks for the infos,

All the Best,

XB-35
 

JC Carbonel

ACCESS: Secret
Joined
Sep 7, 2006
Messages
218
Reaction score
99
I am sure I saw once (but where) a close-up picture of the nose (cowling) of the TBM but never saw anything on the PBY except the article you refer to.
There has been an intersting article with pictures of the similar experiments done with ships on a canadian website (I cannot recall off-hand the adress of the site but I remember the search I had googlised was about the truth in the Philadelphia Experiment)

JCC
 

Matej

Multiuniversal creator
Joined
Feb 13, 2006
Messages
2,614
Reaction score
184
Website
www.hitechweb.genezis.eu
The last one is Yehudi Menuhin, the man, which name was used for this project. ;)
 

Attachments

  • image011.jpg
    image011.jpg
    16.6 KB · Views: 419
  • image012.jpg
    image012.jpg
    18.8 KB · Views: 412
  • Yehudi.jpg
    Yehudi.jpg
    18.6 KB · Views: 297

Archibald

ACCESS: Above Top Secret
Senior Member
Joined
Jun 6, 2006
Messages
5,762
Reaction score
3,979
Alas! I know that right from the moment I posted... :-[
But I couldn't resist, and I'm glad you appreciate it ;)
 

frank

ACCESS: Top Secret
Joined
May 20, 2006
Messages
617
Reaction score
19
Hah! And I always thought it was named after the little guy in the refridgerator that turned the light on & off!


Matej said:
The last one is Yehudi Menuhin, the man, which name was used for this project. ;)
 

elmayerle

ACCESS: Top Secret
Senior Member
Joined
Jan 8, 2006
Messages
1,421
Reaction score
267
frank said:
Hah! And I always thought it was named after the little guy in the refridgerator that turned the light on & off!


Matej said:
The last one is Yehudi Menuhin, the man, which name was used for this project. ;)

It was according to what I've read.
 

dan_inbox

ACCESS: Top Secret
Senior Member
Joined
Sep 3, 2006
Messages
906
Reaction score
461
Tophe said:
Funny for a French speaker, but impossible to appreciate for our English friends, Archie...
Even for French speakers, the near-insult to someone who is dead is rather unsavory ...
 

Longshaor

ACCESS: Restricted
Joined
Oct 1, 2006
Messages
37
Reaction score
4
There was a Nova episode that covered Project Yehudi. I'll take a look through my library and see if I can find it. As I recall there was only one pic of a TBF ashore with a light on the spinner and a couple on the cowl. The did put it to the test on a British APC & it actually worked!
 

Archibald

ACCESS: Above Top Secret
Senior Member
Joined
Jun 6, 2006
Messages
5,762
Reaction score
3,979
dan_inbox said:
Tophe said:
Funny for a French speaker, but impossible to appreciate for our English friends, Archie...
Even for French speakers, the near-insult to someone who is dead is rather unsavory ...

Humour, an unknown word for some people... ::)
 

dan_inbox

ACCESS: Top Secret
Senior Member
Joined
Sep 3, 2006
Messages
906
Reaction score
461
[quote author=Archibald]Humour, an unknown word for some people...[/quote]
The sort of "humour" that manages to be vulgar, to reek in several ways, and to be disrespectful to a dead person, yes certainly it is not for everyone.

Indeed some people enjoy that sort. Those who forgot about the past (or never learnt), and the Le Pen cohorts.
I don't care to be one of those.
 

Antonio

ACCESS: Top Secret
Staff member
Senior Member
Joined
Jan 22, 2006
Messages
3,552
Reaction score
360
Dear Gentlemen,
please try not to go off-topic.
In fact for those who are not French speakers is difficult to understand what you are talking about.

Thanks a lot :)
 

DWG

ACCESS: Top Secret
Joined
Feb 11, 2007
Messages
985
Reaction score
884
A report in the latest AvLeak implies BAE Systems are experimenting with visual signature reduction on a Hawk, and of course visual stealth was a supposed aim of Boeing's Bird of Prey programme.
 

Matej

Multiuniversal creator
Joined
Feb 13, 2006
Messages
2,614
Reaction score
184
Website
www.hitechweb.genezis.eu
I made some quick drawing of that visual stealth Hawk. It is part of british "Chameleon" program, allready tested on manned and unmanned planes.
 

Attachments

  • image013.jpg
    image013.jpg
    10.6 KB · Views: 392

Antonio

ACCESS: Top Secret
Staff member
Senior Member
Joined
Jan 22, 2006
Messages
3,552
Reaction score
360
What is the technological basis of Chameleon? Special paintings or coatings, lights...
 

dan_inbox

ACCESS: Top Secret
Senior Member
Joined
Sep 3, 2006
Messages
906
Reaction score
461
LEDs and LCDs make sense. And actually have the potential for applications on the upper side as well.
 

batigol

ACCESS: Restricted
Joined
Jun 8, 2009
Messages
47
Reaction score
39
XB-35 said:
Hi All,

I'm looking for photographs (and technical drawings) of a Grumman Avenger (and also other aircraft) equipped with these lights (in a concealment experiment against U-boats).

I realize this is a few years too late, but I just came across these on a blog: <A HREF="http://bayourenaissanceman.blogspot.com/2009/09/weekend-wings-34-stealth-aircraft-old.html">link.</A>
 

Attachments

  • Visual Stealth - Yehudi Lights - overall view.JPG
    Visual Stealth - Yehudi Lights - overall view.JPG
    23.4 KB · Views: 413
  • Visual Stealth - Yehudi Lights - detail.JPG
    Visual Stealth - Yehudi Lights - detail.JPG
    38.9 KB · Views: 349

Clioman

ACCESS: Confidential
Joined
Mar 8, 2007
Messages
130
Reaction score
8
For those who want to know more about Project Yehudi, see the article in the Journal of the American Aviation Historical Society, Vol. 15, No. 4 (Winter 1970). Apparently it was successful in that ASW aircraft could get much closer to a surfaced sub before being visually detected, but the advances being made in search radars made the whole approach irrelevant.
 

Nico

ACCESS: Secret
Joined
Sep 9, 2008
Messages
266
Reaction score
34
Hi boys, I never saw an image of the entire Yehudi B-24 but I can post two photographs of details and one about the photocell measuring the color of the light
Nico
 

Attachments

  • Yehudi_104.jpg
    Yehudi_104.jpg
    140.3 KB · Views: 337
  • Yehudi_115.jpg
    Yehudi_115.jpg
    136.1 KB · Views: 323
  • Yehudi_116.jpg
    Yehudi_116.jpg
    518.3 KB · Views: 314

AeroFranz

ACCESS: Top Secret
Senior Member
Joined
May 4, 2008
Messages
2,334
Reaction score
280
Good stuff. Thanks for digging out the pictures and references :)
 

Pioneer

Seek out and close with the enemy
Senior Member
Joined
May 22, 2006
Messages
1,998
Reaction score
453
Wow and here I was just about to ask the forum if they had ever heard of the use of the physiological phenomenon termed isoluminance by the USN during WWII, after I stumbled across this Youtube video "Yehudi" http://youtu.be/aIceh3Bk0Cc
And here it is "Project Yehudi"!
A very interesting use of the Mk 1 eyeball wouldn't you agree! And to think that this technology was dropped like a hot potato, with the advent of airborne radar :eek:
Some great find with the Grumman Avenger pics!!

Regards
Pioneer
 

robunos

You're Mad, You Are.....
Senior Member
Joined
May 1, 2007
Messages
1,992
Reaction score
432
Hmmmm... regarding the video posted by Pioneer, is it possible that the programme it comes from was originally British? In addition to the demonstration of the Yehudi principle being demonstrated on a British FV432 APC, the film showing the attack on the U-Boat seems to show a Short Sunderland...

cheers,
Robin.
 

dan_inbox

ACCESS: Top Secret
Senior Member
Joined
Sep 3, 2006
Messages
906
Reaction score
461
Yes, originally Canadian Navy, then British, then US.
 

robunos

You're Mad, You Are.....
Senior Member
Joined
May 1, 2007
Messages
1,992
Reaction score
432
Thanks, Dan_Inbox...

cheers,
Robin.
 

CJGibson

ACCESS: Top Secret
Senior Member
Joined
May 26, 2011
Messages
1,523
Reaction score
855
The Yehudi effect can be seen any day on the roads. Oncoming traffic with side-lights / parking lights on tend to 'disappear'. Conversely cars with daylight running lights (which are by necessity brighter), dipped headlights or no headlights can be seen much easier as the dark radiator grille is prominent.

Check it out.

Chris
 

alfakilo

ACCESS: Confidential
Joined
Oct 18, 2009
Messages
72
Reaction score
5
Pioneer said:
And to think that this technology was dropped like a hot potato, with the advent of airborne radar

Probably more like the advent of defensive search radar on the subs. The point of these lights was not to increase the range at which targets were detected but to decrease the visual detection range of the attacking aircraft. When the subs could use radar to detect an attacker, the theory behind the lights became moot.
 

Similar threads

Top