Mk.7 Nuclear Device ? Colors

[Corsairfoxfouruncle]

Hello everyone Im currently building an F-84F Thunder-streak down in the 50’s NATO group build. I am building and mounting the Mk.7 Nuclear bomb that comes with the kit. I have done a good deal of research and have come across these two photo’s. ⬇️

I believe these to be concrete filled training devices ? Does anyone know if my guess is correct ?

     The standard Mk.7 colors for an active device should look like this example at the NMUSAF. ⬇️

I have a specific question about these variants. ⬆️ The Red/Brown color of the nose cone ? Any ideas for a match and is it fibreglass ?  Any help is of course greatly appreciated.  

 

Dennis

 

PS - i know i ask a lot of questions in burst patterns and i appreciate everyones patience.

Edited February 8, 2019 by Corsairfoxfouruncle

[exdraken]

Look here Dennis,

That might answer some!

Cheers, Werner

[Corsairfoxfouruncle]

Thanks Werner I've already exhausted that thread and its available links. Im still leaning to the live weapon and its aluminum finish. I was just trying to solve the mystery of the colors ?  

 

Dennis

[Rob de Bie]

4 hours ago, Corsairfoxfouruncle said:

Thanks Werner I've already exhausted that thread and its available links. Im still leaning to the live weapon and its aluminum finish. I was just trying to solve the mystery of the colors ?  

Dennis, I have exactly the same questions as you, both both the Mark 7 and the B28, but I did not find solid answers either, In the end I decided to go for silver (Mr Paint) and Humbrol 180 for the fiberglass. The latter is maybe too dark, it's based on museum examples that are decades old. Shown below are my Belcher Bits B28RE and B28EX.

 

 

Rob

[Murph]

Live Mk7 on an F-100D:

 

 

I think some versions had the radome on the front, and others didn't; the B43 was that way.  The one at the Air Force Museum looks to be accurate; although, I'm not sure about the yellow stripes.  U.S. nuclear weapons generally don't carry stripes, presumably as a security measure, so live weapons can't be distinguished from inert ones except up close.

 

Regards,

Murph

Edited February 9, 2019 by Murph

[Corsairfoxfouruncle]

Thank you both ... I just finished painting the yellow stripes. Oh well can respray the metal. 

[72modeler]

I found a couple of written references to radio altimeters being fitted in the nose of the Mk 7 and other nuclear stores in front of the warhead- would this account for the fiberglass nose cap seen in the color photos that were posted, so that the signal  emitted by the altimeter could be transmitted and received? The written sources stated that radio altimeters were much more accurate and reliable than anaeroid devices

Mike (They call me Oppenheimer!) 😜

[Murph]

17 hours ago, 72modeler said:

I found a couple of written references to radio altimeters being fitted in the nose of the Mk 7 and other nuclear stores in front of the warhead- would this account for the fiberglass nose cap seen in the color photos that were posted, so that the signal  emitted by the altimeter could be transmitted and received?

Yes.  Earlier weapons had some variants with radar altimeters and some without.  As I mentioned above, the B43, and the B57, were that way.  Here's a YouTube declassified training film showing live versions of both weapons LINK.  One version of the B43 had the radar altimeter, while the other version had a longer nose that was jettisoned after release to expose a spike that helped the weapon bury itself on laydown attacks.  BTW, that's why the aftermarket company Spectre Resins offered two versions of the B43  LINK.  For those interested Chuck Hansen's book US Nuclear Weapons: The Secret History explains all this in great detail, and the pictures and info posted here are purely from that and other public sources, since I had the great good fortune to have never dealt with nukes on a personal basis.

 

B43 with radar altimeter on a B-58, where its original high altitude delivery mode would utilize it.

 

B43 used for laydown missions without the radar altimeter and the aerodynamic nose still fitted:

 

B43 with the nose removed to show the spike:

 

Later weapons tended to allow both methods, like the B61, where they figured laying on the ground when it detonated was just as effective as burying itself 1 or 2 feet into the dirt;

 

Quote

The written sources stated that radio altimeters were much more accurate and reliable than anaeroid devices 

 

True statement; although, weapons could carry both.  Here's a "tactical" B28; the blue "dots" on each side of the weapon were aneroid altimeters, and the reason the fighter pilots that had to carry it called the weapon "Old Blue Eyes" (obviously a riff on Frank Sinatra's nickname).  The radar altimeter in the nose is covered here by a protective shroud for ground handling:

 

The strategic version of the B28 didn't use the radar altimeter though, just the aneroid altimeter, since it was designed to be used in the high altitude mode, where an error in fusing just didn't matter due to the size of the BOOM or in the low altitude laydown mode on a time delay.  These were the type of weapons that were lost and recovered in the infamous Palomares incident in 1966:

 

Regards,

Murph

 

 

 

 

Edited February 10, 2019 by Murph

[72modeler]

Murph,

Wow- I sure learned a lot from your post! Thanks for sharing it with us.

Mike

[71chally]

Great info above, I really want to do an RAF strike Phantom with a B43 or 57 hanging from it.

[ReccePhreak]

According to the Book U.S. Nuclear Weapons, by Chuck Hansen, "all Mk 7s after the Mod 1 used a rubber radome de-icing boot (the Abee and Albert radar transmit/receive antennas were located at the front of the bomb) to provide an ice-free surface at the nose to minimize radar propagation attenuation. The rubber boot was attached to a small compressor in the bomb aft of the HE sphere.

The blue "bombs" were a T-63 training shape sometimes referred to as a "Blue Beetle" or "Blue Boy".

 

Larry