How much does the Enterprise weigh?
- Thread starter Captain Robert April
- Start date
This is where the overkill issue comes in. From what we see in TOS, Starfleet does not send starships out to deep space with "just enough" provisions for 90-day missions. A ship may not go for 5 years between replenishing, but there's nothing in TOS that would make it a surprise that starships would cruise around between resupply stops at starbases in the Federation interior while always keeping a multi-year supply on-hand. (Kirk's "Mark of Gideon" remark)
GASP! Heresy! Blasphemy! How dare you!
Actually, I completely agree. It's more than just the fact that the ship is VOLUMETRICALLY smaller than an aircraft carrier (and would therefore be lighter even if the density was the same, wouldn't it?) but I'm struck by the idea that it is, in fact, a spaceship, blessed with the intricate technologies of structural integrity fields, exotic materials, and a general lack of need to stand up to the stresses and pressures of an ocean-going vessel for years at a time. I figure in terms of design and construction its density should be comparable to that of a scaled-up F-14 Tomcat or a 747, not so much an aircraft carrier extrapolated into a starship.
Not that I could defensibly prove it, but I've always privately estimated the ship's mass between 30 and 70 thousand tons (I assume, much like the TMP refit, that some parts of it may be heavily armored). Otherwise 190,000 metric tons only makes sense to me if the warp engines are made out of degenerate matter or something funky like that.
Empty weight, loaded weight, maximum takeoff weight. In the shuttle's case (as with most spacecraft/launchers) Max T.O. would be expressed as a figure for maximum payload to a given orbit; some rockets, for example, can put a 50 ton payload in low Earth orbit, which would drop to about 5 tons for a geostationary orbit.
Enterprise isn't a launch vehicle and it never needs to land, so maximum takeoff and payload are moot points. Empty weight and loaded weight would probably cover the entire spread of its cargo conditions, though I'm sure there's some kind of maximum load that the ship can feasibly carry before its engines can no longer safely maneuver the ship; given that load could only be carried with a tractor beam and/or some kind of docking ring, I have no doubt Enterprise' "maximum loaded weight" is at least an order of magnitude greater than it's empty weight.
Food for thought: the B-52 Stratofortress weighs 83 tons when empty. It's maximum takeoff weight is around 220 tons. That means the loaded aircraft can still (barely) become airborne even if 70% of its mass is bombs and fuel. Since Enterprise doesn't HAVE a maximum weight, it would make perfect sense to me if we are in fact looking at a 50,000 ton space craft packed with 140,000 tons of fuel, food and spare parts. Even a million tons might be explicable if the Enterprise just happened to be transporting a few dozen cases of pressed neutronium to Starbase 4.
Fuel capacity is listed in cubic meters, not mass.
The Ent-D carries 3000 cubic meters of antimatter and 62,500 cubic meters of deuterium, which is enough for 3 years.
Anybody know the density of "deuterium slush" at 13.8 degrees kelvin?
It seems we have no credible motive for someone to have changed it, but we also have no direct sources for it.
That is, we have not seen a copy of the actual document, merely a transcription of it (I thin, as I have seen nothing myself). So errors or changes may have crept in.
What I am saying is, admitting the flaws in our evidence, I agree we should proceed on the premise that the copy we have is genuine unless/until more evidence comes to light.
Fuel capacity is listed in cubic meters, not mass.
The Ent-D carries 3000 cubic meters of antimatter and 62,500 cubic meters of deuterium, which is enough for 3 years.
Anybody know the density of "deuterium slush" at 13.8 degrees kelvin?
Don't know about slush, but the density of liquid hydrogen is about 67 kg/m^3. Presumably, deuterium would be twice as heavy, but since it's probably being supercooled to an insane degree in order to become "slush," I'd guess a density of around (aribtrary guess) 400kg/m^3.
That would give you a mass of 25,000 tons of deuterium slush at that volume.
Plenty of fuel. Probably enough for three years. But it's not the "lion's share" of a ship the size of the Enterprise-D.
Roughed out a model for a Nimitz carrier and took a quick volume measurement: Approx 367,000 cubic meters.
At 102,000 tons displacement, the average density is ~276 kg/m3
Compared to the TOS Enterprise 947' at 190,000 tons, the ave density is ~880 kg/m3 and at 900,000 tons, the ave density is ~4160 kg/m3.
At 102,000 tons displacement, the average density is ~276 kg/m3
Compared to the TOS Enterprise 947' at 190,000 tons, the ave density is ~880 kg/m3 and at 900,000 tons, the ave density is ~4160 kg/m3.
Okay, I think we need to do a little synchronizing here, because I'm talking about page 30 of the US printing of "The Making of Star Trek", the "historical document" I'm talking about is the March 1964 format pitch, and it seems to me that you're mixing them around and maybe even adding in a few other bits.
Would you mind clarifying just what the frack you're referring to?
Well, Bjo recently checked her storage shed in the backyard and, hurrah, hurrah, it didn't leak after all, so lots o' Trekkie goodness should be forthcoming soon; maybe she's got an old copy of the format pitch...?
I wouldn't call it "flaws", just a remote possibility of inaccuracy that cannot be confirmed or denied at the present time.
So, I think what we have is this: Roddenberry had a vague idea of how big a ship he wanted, and put this down in the format pitch in the form of the 190,000 ton figure (FOR THE LOVE OF ALL THAT'S HOLY AND SACRED, STOP REFERRING TO METRIC TONS!!), then went to Matt Jefferies and described the general idea of what he wanted (there's never been any mention of GR showing MJ the format pitch, and no real reason for him to do so, therefore no reason to believe that Jefferies ever saw it), and the design process began, with those earliest C-57D-ish concepts being the first to go because they were too small to fit with GR's 190,000 ton concept. Eventually, over the course of several weeks (need to check the timeline and various interviews with Jefferies) everyone agreed to the design we have now, something that GR could believe was around 190,000 tons of starship.
Sound workable?
Hmm... If we have the E's approximate volume, so what would the E's weight be if using a similar density as the carrier's or perhaps something between ~200 kg/m3 and ~300 kg/m3?
If we accept 216,000 cubic meters as an approximate volume of the E and ~300 kg/m3 as a starting point then we get 63,776.5 LT. If we use ~400 kg/m3 then we get 85,035.4 LT.
Again it seems to me that 190,000 is near a fully loaded figure.
That's heavier than a fully loaded battleship. Believable to me.
A carrier has a design requirement that a starship (probably) wouldn't have: it must float in seawater. Which means that its density must always be less than approx 1024 kg/m^3. Which means that you are not looking at the maximum use that you could get for its volume, only the maximum use that will float in seawater. (note: the density that blssdwlf came up for the Nimitz is about the same as cork, 220-260 kg/m^3.)
A starship is not restricted in such a manner so its density could even be higher than seawater (maybe even four times the density of seawater.
)
If I had LW like blssdwlf does, I would build the TOS pressure diagram, with appropriately thick walls and fitted to the shooting model, and assume some crazy density like that of platinum (21450 kg/m^3) and see what that weighed in as. And what its density was.
That would be what I would do, if I had the software to do it. Alas I don't...
A starship is not restricted in such a manner so its density could even be higher than seawater (maybe even four times the density of seawater.
)If I had LW like blssdwlf does, I would build the TOS pressure diagram, with appropriately thick walls and fitted to the shooting model, and assume some crazy density like that of platinum (21450 kg/m^3) and see what that weighed in as. And what its density was.
That would be what I would do, if I had the software to do it. Alas I don't...
^^True. I figure the typical interior wall is about 0.5" thick based on the only time (AFAIK) we see an interior wall cut-through ("The Naked Time"):
http://tos.trekcore.com/hd/albums/1x04hd/thenakedtimehd0973.jpg
That's the wall facing the corridor. I figure an equally thick wall is on the room side with conduits and stuff in between. It could be simplified to a 1" wall for calculation purposes I suppose.
Then there also those thick arched supports in each living quarters and the briefing/rec rooms to be accounted for which are just the visible part of the ship's internal structure.
And then we have the hull. How thick is it? What is it made of? It's got to withstand most radiation, high and low pressure as well as kinetic and directed energy impacts.
http://tos.trekcore.com/hd/albums/1x04hd/thenakedtimehd0973.jpg
That's the wall facing the corridor. I figure an equally thick wall is on the room side with conduits and stuff in between. It could be simplified to a 1" wall for calculation purposes I suppose.
Then there also those thick arched supports in each living quarters and the briefing/rec rooms to be accounted for which are just the visible part of the ship's internal structure.
And then we have the hull. How thick is it? What is it made of? It's got to withstand most radiation, high and low pressure as well as kinetic and directed energy impacts.
I was trying to envision the simplest hull structure one could quickly assemble for testing purposes. Before going into crazy details, see if the idea produces any interesting results.
What got me thinking about this was that last weekend, to approximate the widest decks of the primary hull, I did some base calculations on just two stacked cylinders (hollow, 410' x 10' with 1" thick walls, using the density of structural steel .294 lb/in^3) and ended up with around 11,000 gross tons as their weight.
What got me thinking about this was that last weekend, to approximate the widest decks of the primary hull, I did some base calculations on just two stacked cylinders (hollow, 410' x 10' with 1" thick walls, using the density of structural steel .294 lb/in^3) and ended up with around 11,000 gross tons as their weight.
Here is an oversimplification on the mass of the hull (just the skin):
If we assume 60,000 sq meters for surface area of the ship
x 1" thickness (0.0254m) = 1524 cubic meters of material.
HSLA Steel (7800 kg/m3) = ~11,880 tons
Lead (11340 kg/m3) = ~17,000 tons
Tungsten (19250 kg/m3) = ~29330 tons
etc...
@BK613 - yeah once the structure is factored in the mass starts to go up
If we assume 60,000 sq meters for surface area of the ship
x 1" thickness (0.0254m) = 1524 cubic meters of material.
HSLA Steel (7800 kg/m3) = ~11,880 tons
Lead (11340 kg/m3) = ~17,000 tons
Tungsten (19250 kg/m3) = ~29330 tons
etc...
@BK613 - yeah once the structure is factored in the mass starts to go up
So IF the TOS Enterprise had the same density as an aircraft carrier it would have a mass of about 60,000 tons. With a lower density figure -- which I would think would be a given for a space craft 300 years in the future -- I would expect the mass to be a bit lower.
I've always believed that some of these starships probably have double hulls of some sort: the outer hull that we see providing the ship's structural integrity and exterior protection, and a more delicate pressure hull underneath it that doesn't need to be as robust and is therefore considerably lighter.
She's quite a bit larger then even the largest battleship, to give you an idea IJN Yamato: hull, dry, without any stores, without boiler water, without anything would come down at almost 46.000 tons, her fully loaded tonnage was just shy of 72.000 tons (source: Anatomy of the ship IJN Yamato) which is only about 26.000 tons more, this includes all the fuel, food stores, lubrication oils, maximum ammo for all calibers, boiler water, crew water and the extra soft toilet paper for the admiral.
So to go from only 85.000 tons dry to 190.000 tons fully loaded would mean 105.000 tons of stuff to carry, thats why I thought that 85.000 tons was a tad on the light side.
