message 0157

• On Riders: Shape and Armor

>From: Onno Meyer <Onno.Meyer@arbi.informatik.uni-oldenburg.de>
>Subject: cherryhlist
>Date: Wed, 2 Jun 1993 08:16:32 +0200 (MET DST)

> 
> from: Onno Meyer
> > Riderships have no vanes, according to _HB_ they are manta-shaped
> > to accomodate the engines and still provide one very small cross-section
> > to pass high-velocity chaff or dust.
> > Another thing I can't believe, but it sounds nice.
> 	Actually the small amount of microscopic dust and such in normal
> space "vacuum" is enough to produce drag when travelling at near
> relativistic speed. Or so I've heard. I've never sat down and worked out
> the calculations.
> 
But at these speeds a ship cannot hope to DEFLECT the dust, it has
to absorb the impact. _HB_ said the rider had an ablative edge.
In this case, the shape of the ship doesn't matter, only the ratio
between exposed area (the front side, I assume) and the volume shielded
by this front armor (that is, the length). If a given armor thickness is
required, it would be the best solution to build an vertical shield.

  __________________________        ____________________________
 /                         |        |                          |
/__________________________|        |__________________________|
   hull (a)                             hull (b)

Assuming the same length for both hulls and a 45 degree angle in hull (a),
model (a) needs about 50% more armor than hull (b).

Of course, I do realize that the bricks I propose are not as nice as the
design described in the books. Perhaps the designers wanted a beautiful
ridership. 
	Onno