Re: FT: FB2 Preview - Obi Wan Tuffley

On Sun, 7 Mar 1999, Channing Faunce wrote:

> Thomas Anderson wrote:
> 
> > the trouble is, a ship's turning ability is not proportional to its
linear
> > acceleration ability; longer (ie bigger) ships turn more slowly. i
think a
> > ship twice as long turns one quarter as fast (ie, takes 4 times
longer)
> > but don't quote me on that. thus, a linear scale between angular and
> > linear acceleration is somewhat incorrect. still, as has been noted,
this
> > is a game.
> 
> But for larger ships, you've purchased larger engines already - 1
Thust Point
> for a Mass 10 ship Does not equal 1 Thrust Point for a Mass 100 ship.
> Since engines purchaced of for any size ship are proportional to the
size of
> the ship, wouldn't they be able to pivot the ship equally?

i'm afraid not. it's really easiest to explain this with algebra (well,
it's easiest for me :-), but i'll put it in English v1.0.4 for now ...

the amount of turning force you get from a given engine is proportional
to
the thrust of the engine and the distance from the axis of turning, ie
the
length of the ship.

the angular acceleration is proportional to the amount of turning force
applied and inversely proportional to the mass of the ship and the
square
of the length of the ship.

thus, the angular acceleration is proportional to the thrust divided by
the mass and length.

the linear acceleration of a ship is proportional to the thrust of the
engine divided by the mass of the ship.

thus, the angular acceleration is proportional to the linear
acceleration
divided by the length of the ship.

this is a *very* rough and ready approximation, but you get my point -
even once you've factored out mass, if your ship is bigger, it turns
more
slowly. also, i think the time taken for a turn is inversely
proportional
to the square of the angular acceleration, so if your ship is twice as
long, it turns four times slower. bummer.

i hope this clarifies things.

Tom