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Can the Enterprise D float?

One thing we do not know: does the saucer section come equipped with compacted Apollo-capsule-style "flotation devices" built into the outer hull?

If it did, maybe that would make the saucer more bouyant.

One thing that concerns me about the saucer is the mass. How much fuel does the saucer carry? Even if the saucer can only run on limited impulse power, (never made sense to me) it would have to carry its own fuel store in order to escape any hazardous situation.
 
Wingsley said:
One thing that concerns me about the saucer is the mass. How much fuel does the saucer carry? Even if the saucer can only run on limited impulse power, (never made sense to me) it would have to carry its own fuel store in order to escape any hazardous situation.

I'm sure they could dump the fuel if necessary.
 
Now, for a pelagic planet (aka, with an all water, or nearly all water, surface), you'd really NEED it to be able to float, just to ensure that the crew would be likely to survive until rescued.

I don't really see how this could be. After all, the saucer is supposed to guarantee survival in all conditions - and most conditions do not include breathable atmospheres. Would it not be much preferable for the saucer to sink to the bottom of the sea, where it would be safe from weather, remain in a stable location, etc?

If the saucer can survive being half-immersed in water and half-immersed in air, it should be able to survive fully immersed in water, too. Perhaps not six miles of it, but if that were the only possible landing zone, then it might be preferable not to land at all.

Nine times out of ten, the saucer would be landing on a planet where the only surface liquid is methane or even helium. No hope of floating anything there. If the saucer could really choose where to land (i.e. if it had a fast interstellar drive), it wouldn't need to...

On a slightly different vein, in the case there was a Class M planet down below without suitable landing sites, would it be possible for the saucer to replenish life support consumables from the planet or its atmosphere without landing? For example, it shouldn't be technologically difficult to send down equipment that can distill and compact the oxygen and nitrogen in the air, after which one might selectively vent the airspaces of the saucer and replace the contents with completely fresh and pure air. It shouldn't be logistically difficult, either: one saucerful of air should last for several months even if life support were not fully functional, and one saucerful should be movable in just a hundred or so shuttle sorties, even if nothing better than the tiny Type 6 is available.

Although in the Trek reality, such replenishment would more probably be via transporters.

Timo Saloniemi
 
Wingsley said:
One thing we do not know: does the saucer section come equipped with compacted Apollo-capsule-style "flotation devices" built into the outer hull?

If it did, maybe that would make the saucer more bouyant.

One thing that concerns me about the saucer is the mass. How much fuel does the saucer carry? Even if the saucer can only run on limited impulse power, (never made sense to me) it would have to carry its own fuel store in order to escape any hazardous situation.
The fuel is HYDROGEN. That's what you use to power fusion devices. Simple hydrogen... doesn't even have to be "heavy" hydrogen... aka hydrogen with a neutron in the nucleus... though that doesn't hurt.

Hydrogen is a gas at standard pressure and temperature. And, by the way, it can be obtained pretty easily through running an electric current through water (breaking the two hydrogens from the one oxygen). That's how we do it in real life.

So they have these largish (but not VERY large, compared to the size of the primary hull) tanks filled with supercooled, high-pressure hydrogen, existing as a slush. (Deuterium is the "heavy hydrogen" I mentioned earlier... tritium is just the same thing but with one more neutron.)

You've simply vent it if you needed to increase the buoyancy. Though, given the overall size of the primary hull and the volume of hydrogen tankage in that hull, it seems like a trivial matter and not worth the effort.

Still, if you DID vent it... and you were in water... you'd have a cheap, and effectively free, source of hydrogen to run your reactor anyway.

As for it needing "floatation devices"... I wouldn't design it so that it would. You'd be FAR better off designing it so that it would float adequately without that. Floatation devices are potential points of failure... and they'd have to be MASSIVE (or there's have to be a ridiculously large number of them!) to compensate for the hull's mass if that's what you were relying on. No, you're better off making sure that it floats on its own.

I'm not objecting to floatation devices in principle, however... just not for something as large as this. I actually incorporated floatation devices into the escape pods I designed for the Vega class(my avatar image). You can see them in their storage cannisters (colored yellow/orange) on the outboard edges of the pod, as seen here:

vegalifeboat32072007qq2.jpg

vegalifeboat12072007eq8.jpg
 
Timo said:
Now, for a pelagic planet (aka, with an all water, or nearly all water, surface), you'd really NEED it to be able to float, just to ensure that the crew would be likely to survive until rescued.
I don't really see how this could be. After all, the saucer is supposed to guarantee survival in all conditions - and most conditions do not include breathable atmospheres. Would it not be much preferable for the saucer to sink to the bottom of the sea, where it would be safe from weather, remain in a stable location, etc?
You're correct, and I'm certain that the saucer would SURVIVE quite easily at the bottom of the Marianas Trench for that matter... provided that it had the SIF operational and the generators operating at that point.

On the other hand, impulse engines (which are basically fusion rockets, canonically and "real-scientifically") wouldn't be very effective underwater. Fire them up, and you'd create explosive shock waves which would surround the entire vessel... not a desirable situation (and not very environmentally friendly either!). So you'd be stuck down there, unless you used a grav system to alter your buoyancy and floated back up. PROPULSION-wise, you'd be crippled.
If the saucer can survive being half-immersed in water and half-immersed in air, it should be able to survive fully immersed in water, too. Perhaps not six miles of it, but if that were the only possible landing zone, then it might be preferable not to land at all.
Ah, but why would you assume that the BOTTOM would be where you'd want to "land?" Yes, as I said before, I believe that a fully-functional saucer would EASILY survive the most extreme environment at the depths of the oceans (considering what else we've seen it survive!). But why would you WANT to do that?

Being at the surface would be FAR preferable, I think... for several reasons.

Most of which are part of the "what happens if things break down" thinking that you really need to consider.

Assume, for instance, that this was a pelagic planet, without any major land masses, but that there's a breathable atmosphere and there's oceanic life. Or suppose that the thing just happened to come down, for instance, in the middle of the pacific ocean... ;)

And then suppose that the reactors fail.

Do you want to be stranded at the bottom of the ocean? Or do you want to be as close as possible to the "unprotected liveable environment" at the surface?

The saucer of a Galaxy-class ship would be able to become, effectively, a "floating city," even if major systems failed... or needed to be powered down. It might even be mistaken for an island (say, wasn't there a Galaxy class ship named Atlantis???).

It's not that you COULDN'T sink it... and there might be situations where that would be the best option, though I can't think of any off the top of my head. But unless you planned to SCUTTLE it (in which case you'd just flood it and it would sink like a rock!), it just makes the most sense to have it designed to float in it's "base" state... without any systems necessary (gravity, propulsion, power, whatever) to allow it to do so.

The real question is... how would you make it SINK then? Again, I think we'd be talking about the gravity systems, though you might well consider flooding a few select compartments if it were really necessary (say, the hangar?)
Nine times out of ten, the saucer would be landing on a planet where the only surface liquid is methane or even helium. No hope of floating anything there.
I disagree. If that was the choice... why "land" at all? You'd be far better off simply staying in space, wouldn't you?

The reason to make planetfall would be (1) an uncontrolled crash (in which case you're likely screwed anyway!) or (2) a recognition that you're more likely to survive, long-term, by setting it down on the planet.

If it's the "more survivable" case... you'd want to be as close to a human-habitable situation as possible. Which PROBABLY means "floating on the surface" even above "landing on solid ground." Don't you think?
If the saucer could really choose where to land (i.e. if it had a fast interstellar drive), it wouldn't need to...
I disagree, again. Look just at our own solar system, for instance.

Suppose that a Galaxy-class were to end up in the past, say 2500 years ago... in our system (perhaps out near Neptune) and were to suffer a catastrophic failure of its main matter/antimatter reactor, resulting in the primary hull surviving and the secondary hull being destroyed.

Now, pretend that this "galaxy class" wasn't aware that it was earth... they just knew that it was a primitive humanoid civilization. They wouldn't want to interfere, but they would want to survive and be able to be evacuated when they could get help.

SO... they'd use the impulse propulsion system of the saucer to make their way to the most likely habitable planet in the system... in this case, ours.

They'd scan to find where the major population centers were, and pick a spot to set down far enough away from those as to be unlikely to be found. Likely right in the middle of one of the two major oceans. For now, pretend it's the atlantic that they choose, for whatever reason.

They'd set down in the middle of the ocean, far from the sight of the primitive humans of that time. But they'd stay on the surface for maximum liveability, and to make it the easiest to be able to contact help... and to allow them to study the local civilizations (greeks, for instance)... and to expend the minimum necessary power to maintain themselves.

Of course.... suppose that the problems occurred in deep space, or in a system without a Class-M world. Then they'd be largely screwed. There would be little, if any, advantage to sitting down on ANY planet, would there be? Again, if you see something I don't, please mention it. ;)

That's why I put low-capacity warp nacelles on the Vega's primary hull... to allow it to make its way to the nearest planetary system with a Class-M world. Those aren't supposed to be "fast" nacelles... just "bare minimum to get the job done" components. Basically, you'd be limited to warp 3.7 (old scale, that's about 50c) or so, unless you wanted to risk burning them out entirely. But that would be enough to allow you to make it in safety to a habitable planet (based upon the Trek conceit that the galaxy is just full of 'em!)
On a slightly different vein, in the case there was a Class M planet down below without suitable landing sites, would it be possible for the saucer to replenish life support consumables from the planet or its atmosphere without landing? For example, it shouldn't be technologically difficult to send down equipment that can distill and compact the oxygen and nitrogen in the air, after which one might selectively vent the airspaces of the saucer and replace the contents with completely fresh and pure air. It shouldn't be logistically difficult, either: one saucerful of air should last for several months even if life support were not fully functional, and one saucerful should be movable in just a hundred or so shuttle sorties, even if nothing better than the tiny Type 6 is available.
Within the bounds of "Treknology" you could certainly do this... but I fail to see why you'd need to "void" sections and them replenish them. It's been fairly well established that, at least in TNG-era times, the life support system can filter out just about EVERYTHING anyway. So you'd really only need to collect matter... ideally the gasses you wanted, but theoretically you could convert free hydrogen into oxygen through matter-reorganization techniques (at a considerable power cost, obviously) and you'd never need to "replenish" planetside at all.

The reason you'd set down, really, would be if you didn't have faith that your systems were going to hold out, or if you seriously believed that there was no likelihood of rescue anytime soon and wanted to "set up house" on a habitable planet.
Although in the Trek reality, such replenishment would more probably be via transporters
I'm not 100% sure about this, but I seem to recall sometime in the tng-and-later era, some episode talking about shuttles being used to replenish something, flying around in nebulae or some such concept. Probably a Voyager episode, but I'm not certain...
 
hutt359 said:
USS KG5 said:
StarryEyed said:
It would float like a cork unless it was made of extremely dense materials.

QFT - the saucer would float.

Ray, pretend for a moment that I don't know anything about metallurgy, engineering, or physics, and just tell me what the hell is going on. :thumbsup:

Well I thought it was fairly obvious the saucer section would float - for the same reason a boat floats because it is mostly filled with air which is less dense than water - hence floatiness.

The only reason it wouldn't float would be if the hull and decks were made of something so dense that overall the Ent-D weighed more than the water it displaced - which does not seem very likely.
 
Why not? To approximate with real-world materials, the density of titanium is about 4.5 times that of water. So if the saucer is about 25% titanium and only 75% air, it will sink.

If we built a large, shallow-diving submarine out of titanium, we'd only use enough to create the watertight, pressure-tight shell - which would be much less than one quarter the volume. More titanium than that would be prohibitively expensive. However, when we build a small, deep-diving sub, its pressure sphere typically is so thick that it will indeed sink despite having some air inside.

In today's spacecraft, the shell wouldn't need to be pressure-tight (except for the insignificant one atm), and it might be thinner still.

OTOH, while possibly trying to minimize mass, future starship designers might even more desperately want to maximize strength. Whether the ship massed two million tons or ten wouldn't be that much of a concern to them, not when they have tech that can propel such masses to near-lightspeed in a matter of hours. The lower end of the performance curve wouldn't be dependent on a few million extra tons.

More importantly, they would also want to minimize volume: why haul around empty air? Much of the saucer would be jam-packed with equipment, then, with just the living spaces built so that they would be empty shells containing air and some furniture. So the real question goes, what percentage of a starship saucer is living spaces? More or less than 75%?

Timo Saloniemi
 
Timo said:
Why not? To approximate with real-world materials, the density of titanium is about 4.5 times that of water. So if the saucer is about 25% titanium and only 75% air, it will sink.

Well given the massive ability to absorb damage and the stresses put upon it by space travel it is logical that the "Duranium" that makes up the hull of the Ent-D is a vastly more advanced alloy than anything we can manufacture today.

I can't see why it would not be both strong and light either - we know that the hull is not very thick from the interior shots - so its not slapped on like armour either.

I see the Ent-D saucer being made of a super-strong, super light alloy - and probably has less mass than we would imagine.

OTOH, while possibly trying to minimize mass, future starship designers might even more desperately want to maximize strength. Whether the ship massed two million tons or ten wouldn't be that much of a concern to them, not when they have tech that can propel such masses to near-lightspeed in a matter of hours.

The on-screen evidence suggests it takes mere seconds to increase to full impulse speeds - so seemingly the propulsion tech is more advanced than even that.

The ship undoubtedly is super-strong but also super-light wherever possible as unnecessary mass is all extra inertia which restricts the vessels abilities in combat. Logically you would not make anything heavier than necessary.

The lower end of the performance curve wouldn't be dependent on a few million extra tons.

Well logically if the ship has twice the mass it would take twice the power to get it from velocity x to velocity y in a given period of time, or more logically twice the time with the same power. It does not matter if it takes the time from just 1 second to 2 - it is still a massive drain on performance.

More importantly, they would also want to minimize volume: why haul around empty air? Much of the saucer would be jam-packed with equipment, then, with just the living spaces built so that they would be empty shells containing air and some furniture.

No it isn't, the saucer contains from most of what we have seen vast areas of open space filled with air - wide corridors, thousands of crew quarters, holodecks - and a shuttle bay you could comfortably hold the super bowl inside.

It even makes sense - if the vast expanses of the saucer were filled with equipment (the question becomes what is this amazing awkward equipment which requires so many thousands of cubic feet of space to store, but I digress) the crew would go stir-crazy on their long missions.
 
Very well-stated, KG5!

Timo is correct about the 1/4-3/4 analogy he used... except that there's no naval vessel, large submersible, aircraft, or manned spacecraft ever built which has that level of density. It's true that "1 atmosphere" is trivial compared to the pressures at ocean depths... but that only demonstrates that "internal pressure" is one of the most trivial aspects of what a Starship hull must be designed to withstand. (On the other hand... you're not talking about it being designed to withstand the stress from that internal pressure, but rather to preclude the escape of internal atmosphere... it's a life-support issue, not a mechanical issue, in other words!)
 
The on-screen evidence suggests it takes mere seconds to increase to full impulse speeds - so seemingly the propulsion tech is more advanced than even that.

I'd argue it takes seconds to rev up the engines to full impulse setting - after which it takes a couple of hours to work up to 0.25 lightspeed, at an acceleration of a couple of thousand gees.

That would explain for example how "fifteen minutes at full impulse" in "Tin Man" doesn't exceed transporter range: full impulse denotes acceleration rather than speed.

Logically you would not make anything heavier than necessary.

Unless you had mastered manipulation of inertia, in which case you might decide that just about every other parameter is more important than mass.

It does not matter if it takes the time from just 1 second to 2 - it is still a massive drain on performance.

But ultimately irrelevant, because the extra second won't make anybody happier or more miserable. We don't build cars out of plastic skeletons and piano wire just so that they would enjoy twice or thrice the acceleration.

No it isn't, the saucer contains from most of what we have seen vast areas of open space filled with air - wide corridors, thousands of crew quarters, holodecks - and a shuttle bay you could comfortably hold the super bowl inside.

Yet take everything we have seen, and you still miss about 80-90% of the actual interiors...

This is just laying the relevant parameters out in the open, really. I don't think there's any doubt the E-D saucer would float if dropped in water. That is, unless it were dropped with the integrity fields off, in which case it would probably split and sink... Starfleet engineers are highly unlikely to have gone for that "let's use 25% solid duranium just in case" approach.

Timo Saloniemi
 
hutt359 said:
Nother question along the same lines...


Would the saucer of the ENT Nil/A float?
Well, the shape is significantly less "space efficient" (the most efficient shape is a sphere, the least is a plane, obviously!). There would be a lot more structure in the 1701/1701(r) primary hull per inhabited (ie, air-filled) volume, as compared to the Galaxy p-hull.

Again, I'd assume that someone probably considered that. But in the case of the 1701(r), in particular, I'd almost have to say that you'd need big inflatable bags (as mentioned upthread) to make it better than neutrally-buoyant. On the PLUS side... with the saucer being SOOO much smaller (and lighter) than the Galaxy class one, and with it still being REASONABLY close to neutrally-buoyant, I'd think you could get by with only a few, reasonably-sized flotation devices.

We know that a couple of the hatches seen on the top of the primary hull are "personnel hatches" but we've seen, in some shots, a full ring of those little hatches up there. Maybe those are where the floats are stowed? ;)
 
David Letterman: "What are we trying out tonight on 'Will It Float?'"

Alan Kalter: "It's the saucer section of a Galaxy-class starship, Dave!"
 
hutt359 said:
Ray, pretend for a moment that I don't know anything about metallurgy, engineering, or physics, and just tell me what the hell is going on. :thumbsup:

You never studied.
 
Futurama stated, "this ship can hold back between 1 and 0 atmospheres worth of pressure, not it is holding back 100."

Always a good moment concerning the water holding back capabilities of space craft.
 
To be sure, starships can hold back the stresses of their own mass when facing thousands of gees of acceleration. That's pretty much the equivalent of being at the bottom of the deepest ocean.

Doesn't mean the ship would remain watertight, though. She could remain structurally perfectly intact for the most part, yet leak like a sieve. Indeed, from TOS "Obsession" it seems that the structure can't even hold back a determined cloud of gas.

Timo Saloniemi
 
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