Ship Mass and SpecPlate validity qustion

[overseer]

Hyper-matter fuel silos are said to out mass the sips that they are on by orders of magnitude (plural), this suggests frigates and cruiser scale ships would mass at tens/hundreds of billions of tons.

The SpecPlate for the Imperial Star Destroyer: "Aggressor" lists its deadweight at 359,000 "mt"
Firstly what is the canon status of the SpecPlate, is its contents even canon?
Also, mt could mean metric ton, or it could mean megaton... a big ; however given that the fuel as noted above should mass orders of magnitude greater than the ship, i would suspect that it would be most accurate to take "mt" as megaton meaning an Imperial Star Destroyer would mass at 3.59e+14Kg. The average density of which would approximate at 4,000 tons/cubic meter.

[Master Bane]

I don't know the status of the specplate, but I know you can get a lower limit for the mass of any Wars ship by dividing the ships power output by its acceleration times cee (P/ac). So an ISD masses at least 1.11 billion tons, a Venator masses 400 million tons, etc.

[overseer]

But wouldn’t dividing power by maximum acceleration supply an upper limit not a lower one for mass, given that the ship is presumed to need 100% of its power output to achieve said acceleration meaning the ship could mass no more than the derived figure and still achieve said acceleration with specified power output?

Also, correct me if im wrong but wouldn’t a 1.11 billion ton ship require 2.93595e+20W to accelerate to 23km/s, which is a full order of magnitude lower than the power output of an ISD 1…
23000^2*(1,110,000,000,000/2) = 2.93595e+20 J
To maintain this acceleration would require 2.93595e+20 W?

ISD:
Power: 7.73e+24W
Acceleration: 23km/s^2

[Master Bane]

But wouldn’t dividing power by maximum acceleration supply an upper limit not a lower one for mass, given that the ship is presumed to need 100% of its power output to achieve said acceleration meaning the ship could mass no more than the derived figure and still achieve said acceleration with specified power output?

No, because that calculation assumes the minimum efficiency of power to thrust (but the maximum for fuel and propellant used to thrust). Also, since Star Wars tech requires absurdly efficient power transfer just to not vaporize the ship and that warships can devote almost their entire reactor output to their heavy guns, it is reasonable to assume essentially the entire power output can also be used by the thrusters.

Also, correct me if im wrong but wouldn’t a 1.11 billion ton ship require 2.93595e+20W to accelerate to 23km/s, which is a full order of magnitude lower than the power output of an ISD 1…
23000^2*(1,110,000,000,000/2) = 2.93595e+20 J
To maintain this acceleration would require 2.93595e+20 W?

ISD:
Power: 7.73e+24W
Acceleration: 23km/s^2

No, 3e20 joules is the kinetic energy the ship would gain upon acceleration from rest to 23 km/s. Atomic Rockets can explain this better than I -
+http://www.projectrho.com/rocket/reactionlessdrive.php
Scroll down to Conservation of Momentum and read to the section. When I first started trying to analysis sci-fi I thought the same thing, that you could just use the kinetic energy to determine acceleration if you knew mass and vice versa. Saxton's site and Atomic Rockets were both really enlightening.

[Connor MacLeod]

ISDs are big ships. There's a certain lower limit you can expect for mass and density because of it, and 360,000 metric tons is far less (nevermind that the Force Unleashed novel mentions them at ~1 million tons as I recall, not tha tthat is any better..)

alot of it also depends on how you interpret hypermatter reactors working. Curtis had his own interpretations/ideas but it was never definitively crammed into canon (its open to interpretation depending on how strictly or loosely you want to do it.

And as noted you only calced the KE fo the ship's own movement. The actual energy expended will be far higher because it has to shoot a lower mass of propellant out the back at much higher speeds to push the ship along, which menas high KE.

[overseer]

I have as recommended referred read the website, and thanks for the correction, it seems obvious now :L.

On how hyperdrives work, well we know a few things about them

-Hyper-matter is superior to antimatter/matter reactions (Death Star novel iirc)
-Hyper-matter is stored in finite quantities within fuel silos
-Hyper-matter can be transfered and annihilated in hyper-matter (and solar ionization reactors?) at rates of thousands of tons per second
-Hyper-matter silos are suggested to out mass the ship by orders of magnitude (which would suggest its stored at densities of at least 1e+6Kg/m^3 - 1e+9Kg/m^3 to out mass hull material on a volume by volume basis).


I therefore would believe the fuel is condensed to extreme densities and that both the fuel silos and reactors must be powered by numerous lesser SW-fusion reactors, which keep the fuel condensed and maintain the hyper-matter annihilation reactor.

I have seen others refer to the hyper-matter reactor as a sort of tap to hyperspace on other sites though.

Although its not canon, Curtis Saxton suggests on his site that ships may only be able to run for several hours at peak reactor output before needing to refuel, for ships that annihilate tens of thousands of tons per second, that would mean total fuel masses of several hundred million tons.

ICS however states the fuels likely out mass the ship by orders of magnitude (significantly higher ratio than he inclines on his site) which would suggest longer operation times. Periods of days-years at maximum capacity (i find the former more likely however). Finally the volume of the Acclamator dedicated to fuel silos seems far higher than many other ships, which may be to accommodate its superior hyperdrive and its long hyperdrive range.

I done some rough approximations and for a Venator to have an operation time of -3 hours, the fuel would have to be stored at 9e+6Kg/m^3. This is likely an order of magnitude higher than the density of the armor, but not the ship itself.

Using the SpecPlate's mass for an ISD and scaling down to the volume of an Acclamator would suggest a mass of 23.04 gigatons. I estimated the mass of the acclamator at 80% solidity to be around 45.312 megatons. The 500 times over jump in mass could be explained by the fuel silos. for the total volume of the fuel silos to be that heavy, they would have to have a density of 1.88e+8Kg/m^3.

Note the above are based on very rough scalings of fuel silos, but should be accurate within an order of magnitude. And it does somewhat rely on the validity of the SpecPlate.

[overseer]

Having aquired a higher res image of the spec plate confirms mt lower case meaning it does mean 359,000 tons not 359,000,000,000 tons

Whic destroys the acclamator calc