allikat wrote:Rail gun projectile shrapnel would likely be below the maximum size that normal ship armour is designed to cope with. Remembering that every ship has to cope with dust at anything up to relativistic velocities, as well as space debris of all kinds.
Noting that a ship may be moving at significant velocities, any impact with fast moving space debris could well be disastrous without armour. So even civilian ships will have enough plating on the hull to ward off all but the largest debris, and hope to have scanners sufficient to detect anything that is big enough to be dangerous.
Another point: Projectiles designed to fragment are massively more efficient at transferring their kinetic energy to the target, a fine thing in space combat. A small projectile at near light speed may well punch through a corridor's worth of rooms and out the other side, but if it shatters on impact, it could very well take out several decks.
Unlikely, the higher the velocity of the projectile, the more it's impact looks like an explosive stuck on the hull at the impact point. Relativistic railgun shots look more like nukes detonating at the impact point( 0.1 gram at 0.99C for example, would have nearly as much energy as the nuke detonated at hiroshima).
As for civilian ships having armor, prohibitively expensive for anything with surface to orbit capability, though I could see the orbital and interstellar craft having a whipple shield. (still wouldn't do them any good against a big chunk of shrapnel)
http://www.projectrho.com/rocket/spacegunconvent.php
If I was a ship commander I would not be to happy in taking part in ship to ship communications.
