The JBD's on each carrier are different. The Nimitz four JBD's were all different sizes. If you are planning on using cats 1 & 2, the # 1 cat JBD is much taller than # 2.
I have this information I got when I built a CAT and JBD for the USS Ike. The measurements are approximate as I could not get the exact mesurement. It is pretty close give a few inches. These are from the time period of the early to mid 80's
JBD # 1 is made up of six sections, each section being around twelve feet high, and five feet wide. That would make the # 1 JBD twelve by thirty feet, with all six raised.
JBD # 2 is made up of three sections, each section being around eight feet high and sixteen feet long. That would make the #2 JBD eight feet by forty eight feet.
JBD #3 is made up of six sections, with each section being around twelve feet high and four feet wide.
JBD #4 is made up of one section being around seven foot tall and twenty four feet long.
And as I said each carrier has different size JBD's, so you would have to research the sizes on the carrier you are using.
Got you totally confused, now?
Berny
Phormer Phantom Phixer 
On the bench
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