Wrong one there buddy...
http://memory-alpha.org/wiki/USS_Enterprise_%28alternate_reality%29\That's the one the gets destroy iirc. I'm talking about the one that was still operation after the first 30 minutes of the movie (well after it fast forwarded into the future) ;P
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and it may not actually be 80 deck levels, but to make the ship look relatively like it, it's 80 stories tall, from the very bottom most level (possibly just being plating) to the very top of the nacelles. So it may be wrong to the movie version, but I'm working on DF, not a 3D modeling program.
Also, I'm considering every tile to be the width and height of 2 meters, so the numbers on the site I provided are halved.
* Length: 2500 feet (760 meters) (380 tiles)
* Saucer diameter: 1100 feet (340 meters) (170 tiles)
* Height: 625 feet (190.5 meters) (Or 80 zlevels in this case... if I just halve that it should be more.. We'll see what happens.)
Those statistics are from the "experience the enterprise" So I'm pretty sure they are close. Now if I could find proper schematics laying out the whole enterprise for me, then I could most definitely lay one out properly, but again, I'm working with in the bounds of DF, so I'm making due. Also, if I made it only 20-25 z-levels it would most likely look very funny.
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And I don't know how you intended that post, but for some reason I was offended by it. So if this whole post comes off rude, I apologize. I did my homework on the spacecraft and I've seen the movie I don't know how many times. My DF may be wrong, but I could care less, I'm making a knock off version. It's going to be WAAAY blockier and look only some what like it. I don't have proper layouts of level by level.