Build the Enterprise

[Duxwing]

I wish we could build this thing.

-Duxwing

[Guest]

Enterprise is a ridiculous design. The saucer is parallel to the engines, making for a really poor artificial gravity setup. A great big part of the ship is off the saucer whatsoever, skewing the COM for no good reason. Turn the saucer 90 degrees forward, flatten the design so that the nacelles line up with the hull, and you get something more sensible (it'd also look more like Earth Force One from B5 rather than Enterprise, but if you want the thing to fly...). Star Trek was good if you didn't care for realism and applied suspension of disbelief in spades. Otherwise, it falls apart pretty much instantly.

If anything, we should be building the Discovery from 2001. We're already 13 years behind schedule, so we better get on it.

[Mitchz95]

You guys know this thread has been dead for months, right?

[metl]

Much like the dude's idea to build the Enterprise.

[Leszek]

This tread may have been dead for two months but I am going to take this opportunity to suggest that if we are going to build sci-fi ships, they should be B5 ships.

Omega class FTW. https://www.google.com/search?site=&tbm=isch&source=hp&biw=1920&bih=1009&q=omega+class+destroyer&oq=omega+class+destroyer&gs_l=img.3..0l3j0i24l2.1829.5250.0.5393.21.14.0.7.7.0.99.1149.13.13.0....0...1ac.1.58.img..1.20.1164.GwGCUiYQ4EE

[Bill Phil]

I like Star Trek, but the Enterprise is not practical AT ALL. Why not an international Nautilus-X?

It took almost 15 years to build the ISS. And it's just a space station and has only enough Dv to maintain its orbit and maneuver the station.

[ZedNova]

Wow... I really admire how your nickname is totally appropriate.

You know what we would do a lot of in all that time? A lot of arguing about wasting money on unrealistic goals, and a lot of 3D renders. That would be about it.

"Somewhat" being a key difference between is and isn't.

I say "Somewhat" because we really don't know where the COM is, because we don't know the mass of each of the parts. If the nacelles and saucer sections are most of it, then it's likely the impulse engines are in the COM.

I suppose it doesn't even matter though, we can always use some star trek technobabble to explain it anyway.

[Itsjustrocketscience]

No, the guy's a grade A nutter. The Enterprise planform is a stupid design for a spacecraft, the centre of thrust isn't aligned with the centre of mass, and it's just too damn big to be any use for anything. Except flying in loops, of course. If you wanted a humungous ship that could only do flips it would be awesome.

Well, Some design changes could be made to put impulse thrusters into proper positions, and the alcubierre drive, well, you don't need to align it with the center of mass because they don't work by applying force to anything. they work by stretching space. And lets be honest. If the Alcubierre drive doesn't work then nothing else will either, it's basically our only shot. Getting it into space may be difficult, but once it's there it would be perfectly feasible if the CoT and CoM are in line. As for the technology involved, yea a 100MW laser could hardly kill a human, BUT a much larger one (say, 20,000MW?) would go through dozens of meters of steel in seconds. Looking at the size of the vessel, that kind of laser could easily be fitted. The gravity wheel wouldn't pull you down, it'd pull you towards the walls. But, when you think about it, why you stand on the floor when you could stand on the walls anyways? Though arranging all the rooms to be easily reachable would require an... interesting design plan. Ion propulsion, considering the Enterprise's size, well, you wouldn't be going very fast now would you? You can literally look at the ship specs and see it says the constant acceleration is 0.0001g "at full engine power" , that's 0.00981m/s^2. It would take you a minute forty to hit 1m/sec so, maybe you should just use warp for everything. after all, the alcubierre drive can be used to go from Earth to alpha centuri and back in a month. or it could go 2mph. It just depends on how much power you pump into your engines.

But you're right. That's the design he has? Dude's crazy, or, maybe this is just one huge troll.

[jwenting]

No, the guy's a grade A nutter. The Enterprise planform is a stupid design for a spacecraft, the centre of thrust isn't aligned with the centre of mass, and it's just too damn big to be any use for anything. Except flying in loops, of course. If you wanted a humungous ship that could only do flips it would be awesome.

of course in the ST universe it's feasible because they have reactionless thrusters, so the engine can be off center as much as you want and still drive the ship along any axis you tell it to

Don't you love Hollywood physics.

[jwenting]

I say "Somewhat" because we really don't know where the COM is, because we don't know the mass of each of the parts. If the nacelles and saucer sections are most of it, then it's likely the impulse engines are in the COM.

I suppose it doesn't even matter though, we can always use some star trek technobabble to explain it anyway.

we know the bridge is in the saucer, because in at least one movie the saucer is detached and they fly it without changing location (unless there are 2 identical bridges, one each in the saucer and the body).

The saucer has its own engines as well.

From schematics I've seen (fan made of course) the central hull section seems mostly weapons systems, crew compartments, and storage.

[K^2]

Actually, since they are planning to put a centrifuge in the saucer (blasphemy!), the off-center thrust would result in precession about a longitudinal axis. So it will corkscrew its way through space, rather than loop-de-loop as you guys suggest. Which, in principle, does get you going in direction you want to be going.

Doesn't make it less stupid of a design, or anything.

[Fox62]

Actually, since they are planning to put a centrifuge in the saucer (blasphemy!), the off-center thrust would result in precession about a longitudinal axis. So it will corkscrew its way through space, rather than loop-de-loop as you guys suggest. Which, in principle, does get you going in direction you want to be going.

Doesn't make it less stupid of a design, or anything.

I just had a humorous mental image of the Enterprise corkscrewing it's way through space, with Kirk asking Scotty, "Why the hell are we spinning?"

[K^2]

I don't know, capt'n. I'm giving 'er all she's got!

[Fox62]

I don't know, capt'n. I'm giving 'er all she's got!

I imagine Spock would then correct the two of them, saying,

"Technically, Captain, the ship is corkscrewing along its longitudinal axis, not spinning."

And Kirk replies,

"That's great, Spock, how the hell do we make it stop corkscrewing?!"

[Rickenbacker]

The Enterprise dude is proposing sending 85,000 tons into orbit, to build an assymetric ship that's supposed to get to Mars using ion propulsion... No, I don't see any potential problems with that at all .

[KerikBalm]

Oh god, he can't even use metric units....

>4000 ISP... that means the propellant is going roughly 40,000 m/s

KE= 1/2 mv^2

To use 1 kg of propellant at this ISP is 0.5*1*40,000^2 = 800,000,000 Joules = 800,000 kJ = 800 mJ

Efficiency of the ion engine will be roughly 50%

1.6 GJ will be needed to accelerate 1 kg of propellant at this ISP

the ship will weigh.. lets say an average of 75,000 tons To accelerate that at 0.0001 gs requires about 0.001 m/s^2 of acceleration.

m_1* v_1 = m_2 * v_2

75,000,000 * 0.001 = m_2 * 40,000

1.875 = m_2

1.875 kg of propellant must be accelerated every second.

That requires 3 GW of power output.

His hypothetical vessel only has 2.5 GW of power output, and he's claiming higher ISPs

So... umm... yea, not going to work.

He's also conveniently ignoring to do any math needed for the radiators that will be needed to run those reactors at maximum power for a long long time (given the 0.0001 g acceleration goal)

BTW, does anyone know if you can use hydrogen gas in a VASMIR engine?

His "impulse engines" are chemical... ...? shouldn't it at least be NTR?

He also conveniently forgets to list dV for the ship, and how much using chemical "impulse engines" to leave Earth orbit is going to increase the mass of the ship due to fuel consumption.

How much dV do you need to get to mars and back anyway?

On 90 day trajectories?

Also, the new space X rockets, the cheapest way of getting stuff to orbit, have a cost of roughly $5,000,000 per ton to orbit.

He wants a vessel that is 85,000 tons. That is $425,000,000,000

$425 billion

That is half his "budget", before we even consider the development and construction costs of this craft. It also assumes a fixed price. Economy of scale works for manufactured items, but not resource consumption. It may be the commodity prices of needed resources is start to skyrocket (while the enterprise payloads won't) once they start being purchased in such large volumes.

It also ignores that such a vessel can't be sent up ~10 tons at a time. Orbital construction would drive the costs up, or larger launch vehicle development (just look at the cost of developing the shuttle by itself).

All this... to get something with very poorly defined mission objectives.

I'd much rather see a smaller craft along the lines of project prometheus- there is no need for a space ship holding 1,000 people.

He claims form must follow function, but then he defines the form as a function, so really its just all about the form.

He wants to see an Enterprise, and assumes that is so important to other people as well, that they'll pay for it even if much better designs are available that will accomplish all the goals he desires.

Also, he seems to think making SSTO transports that the enterprise can launch and recover is not a major problem.

Also, screw the poor people, cut their funding, that trekky wants an Enterprise!

Edited November 18, 2014 by KerikBalm