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Old 12-22-2017, 06:30 AM   #30
kreios
 
Join Date: Jul 2013
Default Re: [Blog] n-Body Politics

Quote:
Originally Posted by ericthered View Post
Of course now when I look at costs I realize that engines are among the most expensive things in the book, and two systems, the engine and the stardrive, cost around 70% of the ship already.
Extremely so. If you look at the Cargolifter from last post, which costs $8.75M, you'll note that I had designed a ram-rocket variant. Only exchanging the engines means increasing the cost from $8.75M to $60M. Hugely expensive.



Quote:
I've done some work. The amount of dv for a given orbit scales with the fourth root of mass and the square root of gravitational influence.

The equations got really complex and than all cancelled out. It was stunning. dv where a planet's influence is g and the mass is M is

dv = (GM)^.25 * g^.5 * .001

Where G is the gravitational constant.
That really is nice. (I tried reconstructing that formula; I'll probably have to repeat it and expand it in a blog entry, since I got other numbers). One of the issues, of course, is that the orbital math becomes more complicated when considering faster transfer burns.


Quote:
Originally Posted by doctorevilbrain View Post
When I clicked on the continue reading link, it said "significant costs of surging". What's surging?
I have updated this passage to "[...] and the arguably significant costs of either coordinating massive numbers of shuttle flights (surging) or in-orbit storage of cargo. Remember - you only have eight hours to load and unload your whole cargo, every hour you waste costs you more than ten thousand dollars."
This hopefully makes it clearer.
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