On 7/7/2015 7:41 PM, Ethan McKinney wrote:
> Keep in mind rotational inertia. You can't just accelerate in any
> direction that you want at a moment's notice.
>
> You want a kinetic round with a diameter of 1m? Ummmm... Let's say
> it's a cylinder 1m long. That's a volume of 3.14 m^3. If it's only the
> density of water, that's 3.4 million cm^3, or 3,400 kg. If it's steel,
> you multiply by about 7.8, for 26,520 kg. 26 metric tons ... That's
> just a ridiculous mass. Over how far a distance are you going to
> accelerate this thing?

Between 29 and 30 meters, give or take.

> If you want to get to 10,000m/s with a barrel length of 100m, you need
> to accelerate it at 100G (give or take). That's not overwhelming, but
> that's not a turret-mounted weapon and you're going to need an
> immensely strong structure. After all, the force is 26,520,000 N, if I
> got all the decimal points in the right places ... If you want a
> shorter barrel, you need to increase the acceleration, so a lot more
> newtons. A 20m barrel pushes it up to about 125,000,000 N. Ouch.
>
> Converting to GJ is left as an exercise for the reader.

I understand the bits that say it can't be done on a turret/gun can be
done in the size required by the illustrations, but that's what I have
to work with and that's what I'm going with as the launch platform.
This is why I had considered that they were instead some sort of fusion
gun that used some form of shaped gravity planes for an extended barrel.

--
Kurt Feltenberger
xxxxxx@thepaw.org/xxxxxx@yahoo.com
“Before today, I was scared to live, after today, I'm scared I'm not
living enough." - Me