Lazarus wrote:

So back to the initial point, you can't increase the pressure of the hydrogen gas indefinitely. At a certain point the pressure would interfere with sublimation. Thus there is a maximum effective pressure which means a maximum exhaust velocity and a maximum ISP of around 1600. That's why to get the higher ISPs you have to use plasma, fusion, and antimatter drives.

Sure. The Isp of Metallic Hydrogen engines is a functional constant. What you can change is the Thrust, so you're gaining the same DeltaV with a shorter burn.

Lazarus wrote:

Mainly that the idea that the only weight is the mass of the hydrogen and the nozzles is not correct. ... 2.5% of the ship's mass may not seem like these components are taking up much weight but since the nozzle for a metallic hydrogen ship only take up around 3-3.5% of the ship (I'm just guestimatting .5-1% for the mass of the ship for the tank walls) those parts are pretty significant.

What it avoids is the "Mass Tax" of a seperate engine system, and has less plumbing meaning fewer points of failure. Together with the above, this makes MH engines well suited for low Isp, low net mass and/or high thrust designs. In retrospect, it probably would have been wiser to compare MH to solid fuel boosters than to compressed gas. Ah well.[i]*Shrug*.[/i]

ORCACommander wrote:

actually with our current tech level ball bearings are more reliable and longer life than magnetic bearings

Current tech, sure. RL Magnetic Bearings are Significantly hadrer to manufacture and incorporate than they would be in EP.

Zoolimar wrote:

Bridge (or "bridge" in case of infomorphs) of the ship probably has additional internal shielding that can alleviate lesser hits. And any hit by a proton beam that goes through armour layer will bear a risk of charges with varying power levels.

Let's say we have a component in a beam which is inducing a charge of 1 Unit. It's [i]probably[/i] only going to be interacting with a small part of the beam, so only a few percent of the beam's strength is going to be deposited into the component. From that portion of the beam, only a few percent are going to be actually absorbed by the component, with the rest passing through. So for every unit of charge, the beam that's actually penetrating is going to be up to a thousand times stronger. It doesn't stop there. The way Beam armour works is that every "layer" reduces the intensity that passes through by a percentage value, so the more you have the better it gets. For example, the Hull plating values I listed will reduce 120KeV X-Rays by a factor of about 708 and the Combat plating by about 346 [B]Million[/B]. All that energy isn't vanishing – it's being dumped into the ship's armor (at best) and into it's internal components (at worst). So either you're getting hit by a weak (RE: Handheld) beam on an unprotected section – or you're being hit with a VERY powerful one, and the issue of point charges is less vital than the Superconductors becoming less "Super", the internal atmosphere becoming so hot it's causing heatstroke and the aforementioned flesh-boiling. As a general guideline, any weapon storng enough to penetrate Ship armor is strong enough to reduce it's contents to a fine paste. Also, charged particle weapons are rubbish. They disperse too quickly, are ridiculously vunerable to deflection and magnetic shields make them impotent.

Chernoborg wrote:

I put up a rough sketch of a bulk carrier design I've been working on. Would this http://eclipsephase.com/sites/default/files/bulkcarrier01_1_0.jpg be like what you're looking for? I'm working on putting labels and explanations on there, as well as probably moving the bridge module to its own page, but I've been itching to get it on here for a while now.

A decent start at the very least. I'm looking forward to seeing where you go with it :D