#### MasterGwydion

##### Emperor Mongoose

Yeah. The math killed Me, but this was well explained. How does the 3I build Tigress-class ships? Do they spend 58.6 years building every ship? If so, then We definitely need to revisit the ship construction math, but using the inverse square method and using your equation is way more math than I tend to want. It does work though, or seems to work anyhow. I figure on something as small as 10-ton fighters, you are better off just using a Fabricator. A very big fabricator. The kind only corps and governments can afford. Like somewhere around 250 at TL-15 for a fabricator that can build 10-ton fighters in a few hours.This is not directly an answer to the question posed in the original post, but I thought you might find it interesting nonetheless;

The linearity of ship construction if strictly following the HG2022 rules bothered me a lil' bit — sure, larger ships take more time to build, but one needs to take into account that a lot of the effort of building a ship is its hull, and when it comes to hulls, the square-cube law comes into play; if you quadruple the volume of an object whilst maintaining its shape, its surface area will only have increase by a factor of 2. So, in theory, if you were to make a copy of a 100 dTon ship, but four times bigger at 400 dTons, its surface area would only be twice as large and the construction time would be somewhere between 2 and 4 times as long.

Following that line of reasoning, I concocted the following house rule: the actual construction time of a ship is given by assuming the base 1MCr/Day construction rate, which is then multiplied by a size factor that is calculated as:`10 * (√x)/x`

, where 'x' is the ship's tonnage. For ships of 100 dTons, this modifier is exactly 1.

So as an example, using the rules as-written in the High Guard 2022 book, aBeowulf-class Type-A Free Trader, which costs MCr46.242 and is a TL12 ships (Construction Time Reduction of 90%) would take`46.242 * 0.9 = 41.6178`

days to build.

Using the above house rule, it'd take that same time but multiplied by a factor of`10 * √200/200 = ~0.7071`

so the construction time would be`41.6178 * 0.7071 = ~29.4279`

days, or just shy of a month*.

*Be that the Imperial Calendar 28-day 'month' or the real-world 30-day month.

Applying the same maths to a much larger ship, such as a Tigress:

A MCr356830.9335, TL15 ship would, rules-as-written, take`356830.9335 * 0.6 = 214098.5601`

days; in other words, about half a millennium and a few decades. Even with the additional 90% reduction for modular construction of ships of 50,000 or more dTons would only bring that down to 58.6years.

Using the house rule, we find that the Tigress would have a size multiplier of`10 * √500000/500000 = ~0.01414213562`

, so its construction time would be`214098.5601 * 0.01414213562 = 3027.81087298`

days, or some 8.3 years. If using the modular construction reduction as well, it'd bring it down to 302 days.

Amusingly, this houserule brings construction times much more in-line, although not exactly so, to the ship construction times as given in Classic Traveller modules (aTigresstook some 56 months to build according toSupplement 9: Fighting Shipsif singly, and 40 in quantity).

Edit: As a further exploration of this houserule; for ships under 100 dTons, the multiplier is actuallylargerthan one, so it implies it takesmoretime to construct a small craft than the straight '1 Day per MCr' rule would imply. This has some interesting consequences:

A Shuttle (95 tons, MCr14.6745, TL12) would take`14.6745 * 0.9 * (10 * √95/95) = ~13.55`

days to build under the houserule.

A Light Fighter (10 tons, MCr9.432, TL12) would take`9.432 * 0.9 * (10 * sqrt(10)/10) = ~26.844`

days to build.

At first it might be confusing for a craft that's one-fifth the size of the other to take nearly twice as long to build, but I actually find this quite reasonable; one's a military-spec craft built to more exacting tolerances, whereas the other is a glorified flying tin can.