US Aircraft carrier deck various dimensions request

[red Dog]

I am looking for more information about JDB sizes. I'm currently doing a diorama for a tomcat and I have different data for the JDB sizes. It seems catapult 1 and 2 are identical in size although placed at a different distance from the catapult shuttle. Catapult 3 and 4 are different but I'm looking for their dimensions as well.

Current size I used are 30.5 feet long but I feel they are too narrow. I found data for Mk7s to be 36 feet long. Which looks much better.

Not sure USS nimitz has the Mk7.

So i'm fishing for some more information should there is someone here with more data and willing to share.

 

The overall plan is to design different carrier deck section I can place one aside the others to enlarge the scene. I am currently starting with 2 sections for catapult 1&2

But to get all details right I am designing the full deck: This will also allow me to cut specific sections later on for other projects: 

Here's where I am now (obviously it's far from being finished and accurate but I am looking for all comments for correction, the idea is to try to get this as accurate as possible before using for building carrier deck sections:

 

 

Thanks for any data you may have

 

 

Edited October 5, 2021 by red Dog

[Oldbaldguy]

JDB or JBD as in jet blast deflector?

[red Dog]

lol, yes sorry JBD, Jet Blast Deflector

[Finn]

No data but here is a not quite head on view of a Hornet about to launch:

 

 

more pics can be seen here showing various details and such:

 

https://commons.wikimedia.org/wiki/Category:Blast_deflectors_(aircraft_carrier)

 

Jari

[robertandy]

Really it depends.  I don't have the dimensions, but having served on 7 different carriers over 26 years it varies depending on class.  Independence were different than Constellations, were different from the Nimitz class I served on

HTH 

Rob 

[LSP_Ron]

That dude has strong arms to be able to hold himself off the ground like that with just one hand!!! 

 

Neat pic

 

 

[robertandy]

1 hour ago, LSP_Ron said:

That dude has strong arms to be able to hold himself off the ground like that with just one hand!!! 

 

Neat pic

 

 

LOL Yep seen that many times and done it quite a few, that's the "I'm too short for this" leap  Man he is getting some air!

[easixpedro]

As others have said, it depends. Between classes and even within the various classes of a ship. Nimitz is almost 50 years old and has gone through a lot of changes.

 

When I built this scene, I had some plans, but they were for later in Kitty Hawk’s life and she had different JBDs. Luckily I found a recce photo that had a Phantom sitting on the cat, and I was able to blow it up to 1/48th and go from there. Depending on what you’re trying to accomplish, it may be your best bet.

 

[robertandy]

If you know which boat and year (or era) you specifically want I can ask over on the Flight Deck Veteran's Group on FB, someone there might know.

[red Dog]

Thanks for the input gents, As I said in the first post, I work on the USS Nimitz, with Tomcat on boards. 

After that I won't be too pedantic about exact measurements. It's just that the conflicting data I have for now are not 10 cm off for rather 6 feet off. 
So I'm trying to get an order of size closer to 30 feet or 36 feet. if It's 30.22 or 35.48 I don't really mind

It's the 6 feet I mind

 

Here are some interesting bits I found:

Quote

The Navy is seeking a passive JBD System (i.e., a system that does not require active water cooling) with physical dimensions (height 14 feet, width 36 feet) that allow for installation in a Flight Deck Pit identical in length, width, and depth to those that house the currently deployed Mark 7 JBD System. 

So 14x36 feet

 

Quote

but generally the JBDs are designed to handle 3182 F (1750 C) for up to 90 seconds. The new system must have a sufficiently high cool-down rate to achieve a 200-degree F tire-rollover surface temperature within 10 seconds of completion of an aircraft launch. All JBDs are currently inclined at a 50-degree angle to the flight deck, but vary in distance. The distance is taken from catapult station 0 (zero) to the JBD hinge line. Catapult 1 is 68 feet, Catapult 2 is 58 feet, Catapult 3 is 68 feet and Catapult 4 is 60 feet (These are minimum distances that can vary ship to ship). Station zero is where the aircraft nose gear hooks up to the catapult, 

and they raise to 50°

The distance from the catapult for the 4 JBD is also very interesting although I suspect there is a mismatch between distance for catapult 1 and 2 (or they are numbered the other way) because on all pictures we can see that JBD2 is placed further aft from the catapult2 station0 than theJBD1/Catapult1)

The temperature resistance and cycle to allow the aircraft to roll over them once they are down are insane. Using sea water to cool them is a maintenance nightmare for sure. 

 

Quote

the current Mark 7 Mod 0 JBD dimensions are 36 feet in length by a raised height of 10.7 feet. The recess in the deck where the JBD lowers into has a thickness of roughly 9 inches. It raises to an angle of 50 degrees relative to the flight deck. For ease of retrofit into existing carriers, any new JBD cannot exceed these dimensions. 

Here' s the raised height of 10.7 feet at 50° and the 9inches recess will be usable. These dims also seems to imply to allow backward compatibility that the ones fielded now are not greater than that. Supposedly I may accept the fact that even without proof, all active carriers have somehow been updated with later Mod0 Mk7 JBD. 

 

Again, I won't be too pedantic, I'm looking at something that doesn't strike the eyes in proportion.

Edited April 3, 2021 by red Dog

[alain11]

hi

years ago , I built a flight deck at the 1/48 scale , diorama based upon the Verliden deck at the 1/72 . So ,for what it's worth , the overall dimensions of the six JBD panels  , are  24 cm X 7 cm at the 1/48 

 

[red Dog]

I have that one as well Alain, but when I see the catapult starting so close to the JBD, I don't trust any of it's dimension

So far 36x14 feet seems pretty good and that would translate to343x133mm in 1/32 and  228x89mm in 1/48

Since the 3 main JBD are made of 6 sections, 36 ft makes sense and induce 6 feet per section.

JBD4 is 4 sections, thus 24 feet wide

 

I think I'll stick to that for now  

Edited April 3, 2021 by red Dog

[red Dog]

Another question if I may?

 

I am trying to guess estimate the height of the barrier poles. 

I found out that the barrier is between wire3 and wire4 and it has it's own reel as well. But do you guys have any idea of it's dimensions? Mostly the height of the pole

 

Thanks