Spaceship Design

[Jay-qu]

I don't want to spend the whole thread arguing over which propulsion system to use. Especially when they are all equally difficult. Putting a power beamer in a polar orbit around the sun is probably not that much less difficult that producing 30 milligrams of Anti-matter and a sheet of U235 125M in diamater.

 

Jay, can you add a poll to the thread? Like "what propulsions should we use?"

 

The options I count so far are.

 

Chemical Rocket

Ion Engine / Advanced

Solar Thermal Rocket with Beamed Energy

Antimatter Sail

Solar Sail

Nuclear Propulsion (I'm assuming either Nuclear Electric Rocket or Nuclear Pulse)

A combination of these.

 

Does anybody else have any to add? And then we can move on to a different system...

 

TFS

you read my mind :cake: will do

 

and Kayra, dont you think that there are equal amounts of trouble with the solar beamed power.. for a start what do you do about the fact that if we change direction (at earths distance) the platform wont know until 8 mins later to make a correction in where it is beaming... anti-matter once getting around the creating, which can currently be done just not in the quantities needed, is our best bet.

[Jay-qu]

ok so this is what we have so far, if anyone wants to add an idea then let me know we can have up to 10, I will post the poll in a few hours :cake:

 

Chemical Rocket

Ion Engine / Advanced

Solar Beamed Energy

Antimatter Sail

Solar Sail

Nuclear Propulsion

Ram Scoop (or alteration of)

A combination of these (please specify)

[Kayra]

you read my mind :confused: will do

 

and Kayra, dont you think that there are equal amounts of trouble with the solar beamed power.. for a start what do you do about the fact that if we change direction (at earths distance) the platform wont know until 8 mins later to make a correction in where it is beaming... anti-matter once getting around the creating, which can currently be done just not in the quantities needed, is our best bet.

 

Good point. Let’s look at both drive systems.

 

 

Antimatter

http://www.engr.psu.edu/antimatter/images/ICAN-121.jpg

 

Pros

1. The system is capable of a high specific impulse as well as high Delta V at the same time (a rarity in space propulsion)
   
2. Carries it’s own fuel
   
3. Course changes can be made instantly.
   

 

Cons

1. Large shielding required as most of the resulting energy is X-Ray and Gamma
   
2. Inherently dangerous fuel to manipulate.
   
3. Expensive
   

 

 

Solar focused energy.

(No link that I know of, this is my own concept)

 

Pros

1. The system is capable of a high specific impulse as well as high Delta V at the same time
   
2. Reasonably safe propulsion method
   
3. VERY low operating cost
   
4. No shielding required
   

 

Cons

1. Course changes have to be coordinated between projector at the sun and the ship. (unless a backup propulsion system is used)
   
2. Keeping collector on the ship in the proper shape and pointing in the correct direction may prove difficult.
   
3. Planetary shadows disable power source.
   

 

Conclusion:

Both systems for all practical purposes provide all of the energy the ships need to attain high specific impulse and high delta v. The other drawbacks of each system can mostly be overcome. (Shielding for the Anti-matter, proper engineering of the collector for the Solar, Etc)

 

Currently, Anti-Matter costs about $62.5 trillion per gram to produce. By the time the fuel is required for interplanetary travel, the costs should drop to about 10 million per milligram. (a reasonable value for space travel).

Note: This cost does not include the debt load of the facility used to produce the antimatter.

 

The ability for a ship to be able to change course mid flight to avoid unknown hazards might be critical. This would mean that the Solar design would require a backup engine (and all associated extra mass)

 

The bottom line is that in order to use anti-matter we will require a deeper understanding of the physics involved, and as the technology is inherently dangerous, a considerable amount of testing.

 

The Solar propulsion system is possible with today’s technology (or nearly so), at a fraction of the price. What is required is the engineering.

 

And remember folks, I am biased towards the Solar concentrator so feel free to check my "facts" :Alien:

[TheBigDog]

I am talking about nuclear pulse rockets. We have already done practical experiments on them back in the 50's and 60's. We have plenty of fuel available in our nuclear stockpiles. I would not launch the mothership from the atmosphere. I would assemble it in orbit before firing it up. I am working on some sketches.

 

Bill

[TheBigDog]

Here are a front and side view of the ship. Dimensions are arbitrary.

 

Ring shows a four layer living area totaling 48 sections. These rotate where they are held at the ends to keep the direction of "down" relative the g force being experienced. While the ship is accelerating the spin rate is adjusted to keep the living quarters at 1G. While coasting the ship is a maximum spin to maintain 1G. This area is meant to house the people plus the self sustaining resources to keep them fed and hydrated indefinitely.

 

The center cylinder is the nuclear fuel plus the liquid fuel used for trim controls and fueling the probes and shuttles. It is meant to last for 100 years of full throttle, plus multiple missions for the smaller craft, so it is big. I am not sure if the proportions are correct. The yellow section is the nuclear rocket that propels the ship.

 

The green area is the payload section. Seven large storage areas that can hold shuttles, probes, satellites, etc. The docking bay is at the nose of the center payload section.

 

Bill

[Jay-qu]

Ok polls up, come and get it :)

[Racoon]

I voted Nuclear.

 

Because it seems most realistic.

Cool Thread and Responses guys!

[TheFaithfulStone]

Bill,

 

Can you make your picture a little narrower? It's messing up the style sheet for me....

 

(nice ship, btw)

 

TFS

[Pyrotex]

Here are a front and side view of the ship. Dimensions are arbitrary....

major cool drawing, TBD! :rolleyes:

what app did you use to draw it with?

[Eclogite]

I also applaud the quality of the drawing, but question the practicality of the concept. If you are planning on any sort of velocity at all you need to have a meteor shield up front protecting the whole thing. If you intend to approach significant fractions of the speed of light (even 10%-20%) you had better have shielding that will protect you from impact with interstellar gas, large molecules and nano-sized dust. Space isn't empty.

[Kayra]

I also applaud the quality of the drawing, but question the practicality of the concept. If you are planning on any sort of velocity at all you need to have a meteor shield up front protecting the whole thing. If you intend to approach significant fractions of the speed of light (even 10%-20%) you had better have shielding that will protect you from impact with interstellar gas, large molecules and nano-sized dust. Space isn't empty.

 

The design looks to be more then adequate for interplanetary travel.

 

If it is going to leave our solar system, then perhaps a modification to the design might be called for.

[TheBigDog]

Thanks guys. I put that together using PowerPoint.

 

As for shielding, the cargo sections protect the fuel tanks and the engines. They are modular both externally and internally so that small hits don't cause catastrophic losses. The same is true of the passenger rings. Only one is an exposed leading edge. The further back in the ring the safer you are from hits (maybe?). They are all modular and sealed from one another.

 

In the end though you take your chances. I don't think you could adequately armor to protect against high energy hits. I was thinking of using a detection and laser obliteration system. And an auto evade system for big things.

 

Bill

[Kayra]

As for shielding, the cargo sections protect the fuel tanks and the engines. They are modular both externally and internally so that small hits don't cause catastrophic losses. The same is true of the passenger rings. Only one is an exposed leading edge. The further back in the ring the safer you are from hits (maybe?). They are all modular and sealed from one another.

 

In the end though you take your chances. I don't think you could adequately armor to protect against high energy hits. I was thinking of using a detection and laser obliteration system. And an auto evade system for big things.Bill

 

Should be interesting playing the evade game at 20% c :hyper:

 

Good idea using the leading habitat rings as shielding.

As you flip over to decelerate, you can just move the stuff from the leading to the trailing edge (oops.. it would still be leading wouldn't it)

 

You Might even consider using frozen fuel in the leading ring.. good protection and no wasted weight.

[Pyrotex]

Here is a side view of the Turtle starship. I hope this shows up in the posting like TBD's did. Here goes. If you don't see a picture here, then email me and tell me how to do that. Drawing done in Canvas.

 

This is a side view of the oblate spheroid, with central axis running vertically through center of drawing. Four of the eight winged landers are shown. Two of the eight anti-H/water engines are shown in pink. The yellow items contain water as shielding and reaction mass. Blue shows the circular magLev train/habitation modules. Purple shows various storage containers. The anti-H bottles are in green.

[Pyrotex]

What may not be clear in the drawing is the sheer size of the Turtle starship.

Width is one full kilometer. That's about 0.4 miles, off the top of my hat. 3,300 feet, off the bottom of my butt.

 

The winged landers are about 450 feet long! The Saturn 5 Apollo rocket stood about 330 feet high on its launch pad.

 

The water in the outer-most toroidal ring flows counter to the motion of the magLev train, balancing out gyro forces. It also serves as shielding. The huge water ring just inside the landers, can be frozen to serve as a heat sink while in "interstellar travel" mode. It also shields the magLev train from the engines. There is a third water tank, disk shaped, that shields the cargo holds from the engines.

 

Except for the magLev train/habitation cars, the interior of the Turtle is in vacuum at all times. So the hull doors can be opened to allow the engines to fire, or the landers to egress/ingress without losing atmosphere.

 

Since the magLev train travels at over 80 mph, there is a second much smaller magLev train system just above the main one, in the diagram. It allows single cars, holding only maybe 40 people at a time to leave the main habitation cars, decelerate until at zero mph {now in zero G} and from there, transfer to landers or to mainenance tasks in pressurized "taxis" or spacesuits.

[bpjg2fat]

trippy

[Jay-qu]

Thats really good pyro :hyper: I was just thinking though - that with your design it has a very large cross-sectional surface area in the direction of travel, a circle of diameter 1km, pretty big. Wont this be more suceptible to taking hits from intersteller matter and such, or is it negligible