So while sitting at a client's system watching progress bars (similar to watching grass grow), I noticed a number of people discussing the "947 foot" Enterprise. As a general reference (that is, talking in vague terms) that is fine... but when people actually attempt to apply that one length to either of the models as a scale reference, then you are going to have issues.

Matt Jefferies drew up the plans for the original models, and for the most part assumed that the builders of the models followed his plans. But the thing is, the first (33 inch) model was started before the final plans were finished, and the second (11 foot) model was built in three weeks. Add to that the fact that the Enterprise is not a single piece, but is actually four pieces arranged together, and using the model's actual dimensions becomes an issue.

So, now that I've brought it up, how do we deal with this issue?

First things first... throw out the

*947 foot* length when discussing the models.

Jefferies' plans on the page were 33.75 inches in length, the 33 inch model (from my research) appears to be 33.67 inches in length, and at one-quarter scale the 11 foot model is about 33.5 inches in length. So right there... overall length wasn't preserved between the original plans and the models, and no one should really be surprised by this.

But Jefferies gave us additional dimensions of the four main pieces. The primary hull has a diameter of 417 feet, the secondary hull has a length of 340 feet, and the nacelles are each 504 feet in length. I have generally considered the primary hull as the gauge for everything else as it is

*primary*, though I totally understand the argument for using the length of the secondary hull (as it's length was preserved in Jefferies' drawings of the Phase II Enterprise).

So if we equate 417 feet with 15 inches (the diameter of the primary hull on the original plans), the length of the secondary hull would end up at 12.23 inches and the length of the nacelles would end up at 18.13 inches. On the page, Jefferies original plans had the secondary hull at 12.125 inches and the nacelles at 18.125 inches.

What about the 11 foot model?

As everyone seems to want to use the 11 foot model as the template for the exterior of the Enterprise, we should make note of it's dimensions compared to the original plans... noting that the 11 foot model was to be built at 4 times the dimensions of these original plans. At one-quarter scale, the diameter of the primary hull is 14.8125 inches, the length of the secondary hull is 12.25 inches, and the length of the nacelles are 18.0625 inches.

If we go with how

*I* plan to proceed (using the primary hull diameter as a gauge), we end up with a secondary hull that is 344.9 feet in length (almost 5 feet longer than Jefferies' 340 feet) and nacelles that are 508.5 feet in length (4 and a half feet longer than Jefferies' 504 feet). And when assembled, the 11 foot model comes out to 943.65 feet long (a little more than 3 feet short of Jefferies' 947 foot over all length).

The other reason for using the primary hull diameter as a gauge for scaling is that it worked out nicely for both the original plans and my replica of the original model. 417 feet is 5004 inches. That means that 15 inches (the diameter of the primary hull on the original plans) is almost exactly 1/333 scale, and 10 inches (the diameter of my model) is almost exactly 1/500 scale.

Additionally, though I'm pretty sure no one is going to understand what I mean by this, I have been looking at all this sort of like the

*Knapsack Problem*. That is to say, I give certain data points a value... and when I have to make a choice between conflicting data I pick the data with the higher value.

In all actuality, we all do this when looking at this puzzle to some degree, we just don't all apply the same values to the different data. And that is why even with all the same data we can still end up with significantly different versions of the Enterprise. One of the things I put the least value on are ideas that I've come up with on my own... which are almost always the first things to go as I get more data. For others, that is the fun part (adding their own signature to their designs), but in the end I'm really only concerned with what Jefferies was thinking of back when Star Trek was being made.