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Toy Killer
2013-09-19, 12:11 AM
I'm preparing a game of Dread, set in the future on a drone repair ship. I know the forum has it's share of arm chair astronauts (And who knows probably one or two actual astronauts:smalltongue:) so, I figured I would run it by yall and see what constructive criticisms and advice you can give.

Thanks in advance!

Warning; Larger then it appears!

Class XIX
Welcome aboard
Drelliades are Celtan Class workships. Operating with a minimal crew of five or six, they tend to malfunctioning drones on work sites. While there are over two hundred of functional work sites in the galaxy, they can be watched over from just fewer than 30 Drelliade crews. The fuel and food upkeep costs alone are starting to etch into the fiscal securities of the job market.
However, they remain in place for now; relics of an easier time in resource gathering. Celtan Industries has slowly retired more and more of their revolutionary ships, leaving more and more jobs revoked in the name of profits. Now, a job on a Drelliade is synonymous with hardship and desperation. The hours are absurd, the work is drastic and chaotic and the schedules are drafted by insane expectations. The work on Drelliades requires extensive schooling and training, but the pay will hardly cover rent.

Rumors persist of people who got picked up from these **** jobs for bigger and better careers, but that’s usually discussed as half-hearted jokes. Nobody wants to work for Celtan, and if they had the skills to be hired by Altech or Christian Carbin, they wouldn’t be donning the same ****ty coveralls from a drain pod with a notorious fragile G-stabe. Even the Drelliade mechanical codex for the Gravitational Stabilizer recommends a dirty look as diagnostic repairs in some of the older prints.

But Celtan isn’t going to invest in a job market they are actively attempting to rid themselves of. Each year, more drones are replaced and updated with improved ‘Opti-safe’ protocols. These protocols allow the drones to continue working with fewer systems operable. This has two profound effects, It keeps them working even when they are ‘Broken’; and it makes the repairs required to be performed to be more taxing. These complicated repairs make the competitive job more intense and the work environment downright straining.

It’s not unusual for crew members to take up narcotics, have fits of depression and lapses in sanity. Class 19 on a droid is an Operating system’s error, causing a variety of erratic and odd behavior. The slang for these general mental issues is “Class 19”, as in, “Jacobs spent the last 7 hours bubbling his stir-ins. I think he’s going Class 19”.

In the past, Drelliades had something that passed for a medical bay. With the increased cost for updating Divinci medical bots, they were removed. In their place, each crew member is taught basic life saving techniques and use of medical supplies. An emergency medical departure from the job can be performed, but the after process is so intense and under such scrutiny that the crew is immediately landed off their ship until a proper verdict can be placed is on whether the event was truly an emergency or not.

During this time, the crew is not paid and very likely to be placed in the back of the line for reflight when a verdict does come back. If it is deemed a medical emergency, the crew goes back to work after a couple of months. If it wasn’t, in the eyes of the corporation, they are immediately fired and charged for the loss of profits evaluated due to their malingering.

Given the erratic and odd decisions made in the past, most crew’s would rather off a fellow rather than risk abandon their job. It’s not unusual to see Drelliade crews with cybernetic limbs, digits or implants due to work place injuries or the restraining there of.

The 9 to 5

Drelliade’s primary purpose to update, repair and replace drones on off planet worksites. These worksites are usually neighboring planets and the occasional moon; but ring belt jobs scatter the roster from spin to spin.

These drones excavate, build and level the terrain, gathering resources. Commercially, the drones are a huge asset. Man labor wouldn’t be able to work on these planets until a 4 phase terraform took place. Even if the expensive process were considered, over half the planets can’t even support such an endeavor and are more valuable in their natural state.

With the droids being such an important investment to the company, their upkeep is just as vital. With two hundred people, they can keep a thousand drones up and active. In the early day of droid labor harvesting, they had over a thousand crews, or six thousand people, keeping up with just over thirty thousand drones. As resources and sites were established, the drone technology surpassed their need for workers. More efficient, faster and self reliant with only more critical and complicated repairs needed in return.
The need for a Drelliade crew is still required, at least for now, but the work load slowly increased while the work force slowly drifted down. The state of the art Drelliade ships are slowly getting taxed out of commission.

When Celtan commissioned its first Drelliade, it was the crown jewel in travel efficiency. The crew pods, later known as drain pods, allow the ship to secure the G-stabe of the ship while the crew sleeps. The repair bay doubles as the kitchen and dining hall. The Drain pods were able to play S-Mail messages and videos, allowing the crew to strike the drains when they weren’t ready to sleep and still turn off the ships exhaustive G-stab.

The piloting system is nearly automatic, as the ship itself is practically a drone. It had pre-programmed personality for interaction with the crew, but that feature was eventually disabled in later years as it bore some unsettling results if left operating for too long. The S-Mail systems were disabled as well, as it was rare for the Drelliade to be within range of communication with anyone beside the ship itself.

The crew dock at a local station, where they have a few days to spend of their own time. The ship is refueled, stocked and loaded with a schedule, including coordinates, dates and services required. The crew members return and travel for a day or so between work sites. At the work site, they rush to get everything done, while the ship recharges and updates the schedule based on the crew’s progress. Once all the work sites on the roster are completed, they have a few days return back to dock.

A typical cycle has about ten to sixteen jobs on it, but it’s not drastically uncommon to have thirty sites on the to-do list. So a crew member with a family doesn’t usually keep it shortly after joining a crew, as he is rarely home a third of the time he is home.

As a ship arrives at the planet, the Drelliade emits a signal to the droids of its presence, usually called “whistling for the dogs” or “dinner bell” as the drones tend to drop what they are doing to meet the ship. Once landed, the Security Officer brings which ever droids on board one by one in planet specific suits. The Wetware Officer repairs the hardware of the drones, and the Mechanical Officer tends to the physical damage and joints. Then the Programming officer tends to the software and updates the drone, and the process is repeated until all the drones are back to work and functional.

The Captain checks off the progress signs off the work as complete. He coordinates the crew and makes sure those safety regulations for the planet and drones being worked on are complied with. When the crew feels they are done, they double check their work with a service indate. When cleared, they move on to the next site.

Of course, with a job as this, a typical work day isn’t typical. Drones run away instead of approach the ship. Parts are missing for repairs. The last crew did a **** Jury-rig to keep the drone running. Drones get stuck in the weirdest places. The planet is experiencing catastrophic weather. Such is a day in the life of a Drelliade crew member.

The Job Description

Each crew member has a specific role to play onboard, but no one is the only qualified member. Even the captain is defined by being the most qualified. One could argue the Security Officer as being fairly easily replaced, but no one would want his position in the first place.

The security officer is usually a freshly discharged military member. The use of foot soldiers has become one of presence in the current forces, as drones are hardly reliable to rationalize something like dangerous intent, after the 4tb processing ban on AI. However, in warfare itself, foot soldiers and drones fight side by side, each covering the other’s weaknesses. This experience in working with the drones lends itself naturally to going into dangerous places to retrieve the drones from rockside.

Security Officers tend to get rotated out frequently. Occasionally the find a ship they particularly work well with, but lacking the engineering and knowledge on how drones work, the frequently feel left out of the clique. Occasions of battle fatigue can on top of being disrespected as dumb muscle on a ship for a month or so while being the only one expected to carry a weapon doesn’t lend itself well. Giving the prior GI the thought they are transferring out soon helps keep them from doing anything violent, however.

Wetware Officers tend to have burnt finger tips and an overly critical lack of humor. Their job requires a sense of precision to do right, and it only attracts a specific kind of person to pursue much longer then a single course or too in college. So much, to a point, that being hired as a Wetware Officer, by company regulations, prevents you from being placed on board a ship as captain. It’s not uncommon for Wetware officers to be fired before reaching a point in their career for being in the company for too long and out ranking their fellow crew members.

Programming Officers are odd, they tend to overcomplicate simple problems before solving them. Some say it’s a simple fascination with problem solving, while others say it’s just useful in programming. Whatever the case may be, they are frequently looking to improve, fix and upgrade things around them. While they have solid job security (it’s difficult to match Celtan’s pace of leading programming design, and they tend to enjoy the actual work side of the job), it can be tough keeping them entertained with drones. Most of what they do is simple updates and reboots, and personal tampering with the systems is forbidden by company law. They do tend to gravitate to each other and make some startling innovations in the company technology though, usually looking for the big break out of crew member and into R&D.

Mechanical Officers are known for their creativity and improvisation. Often times, a job will be sent out for and prepped for, only for the actuality of the situation to be much more dire then originally assessed. A dragon in a pinch, they have saved a number of crews from critical, unprepared situations with ingenuity and luck alone. While they may not have great people skills, and sometimes can get a bit full of themselves, they are more than willing to teach a fellow engineer the ins and outs of their work.

Captains are the centered around teamwork. Having been on a number of ships themselves, they know the value of a well oiled machine. Their job involves accounting for the actions of their crew members and answering to the company when they call. They know the routine, the drill, and have it marked on the calendar. They say that before someone is really a captain, they have to ‘hear’ the ship’s song. The thousands of drones humming slightly out of sync with one another create a harmonious week long buzz. That’s how they know everything is alright.

The grand tour

The ship is cramped, tight and never goes too long after leaving port before it starts smelling of body odor again. The engine is uncomfortably close to the ‘Sound Proof’ drain pods to get a good night’s sleep and the ship board copy of “The Drelliade Mechanical Codex” is almost always out of date with the technology on board, making out of port repairs dangerous at best. The ship board computer beeps and whistles a hundred different ways to communicate. Sure, you get use to the regular notices, but every once in a while, it makes a bizarre noise that no one seems to know what it means.

The ship is broken into 5 crew spaces. There is the hanger, where the drone is brought on board and decontaminated with the security officer. The prot suits are varied by planet atmosphere and dangers, with a selection of masks for further customization. A shard bike is available for wrangling loose drones, when they are too close to be flown after. It also has the only private bathroom.

The work room has 5 of the drain pods on the sides with a variety of fold out tool selves installed on the deck, keeping the tools from flying through the shaky walls when the G-stabe is turned off ship wide. A few lockers are hidden along the ship, each ship is different, but usually one is in the work room. The work room also doubles as a kitchen (as much as you need for stir-ins at least) and dining room. You could call it a living room as well, if you call ship life living…

The drain pods are small pods that allow you to roll over, stretch (as long as your shorter then 5’8”) and sleep. It also hooks up to the sezilier suit and can microbathe. People frequently comment that a microbathe never seems to actually get one clean, but it does the best it can. This microbath is why it’s called the drain pod, as it’s obvious when someone is inside, due to the constant draining.

The third room is the Bridge, more for show then anything. It has useful information and the only really functional computer on the ship. It can receive and send S-mails to the company and is the only way an emergency override of the schedule can be accomplished. The ship has manual steering abilities, but no one has ever really used them. The steering is controlled by the drone, and without the drone it would take 4 people to make any kind of difference at the speeds the ship travels at. Besides, if the drone went out, the steering is the last of your worries.

The engine room is only a room if you are an engine. Most of the space inside is filled with spinning parts and electronics, but the occasional fix has to be made on the fly if the engineer can fit in the wedges of openness.

Finally there is the medical “Bay” or as most call it “The Boo-boo closet”. The sixth drain pod is available in here, and also has a lock feature enabled. So if a crew member goes class 19, he can be safely held until they get back to port. It has a variety of antibiotics, an AED, wound dressings, tourniquets, liquid stitching and a few medicinal narcotics. Little known fact, most people who are fired from the company are caught stealing from the boo-boo closet. It also has an eye flushing sink, which doesn’t take an engineer to figure out how to use it as an impromptu shower. It’s also a reliable place to have private conversations.

Yora
2013-09-19, 02:18 AM
Do you have a specific question?

Sir_Mopalot
2013-09-19, 03:30 AM
Looks good if what you're aiming for is a Battlestar Galactica level of hardness, but I'm a little confused, your intro and title imply that you're looking for critique on the engineering of the ship, and then you spend the whole write-up talking about the people on board. That's great for a horror game, but, like Yora, I dunno exactly what you're looking to hear. I guess one thing, either you're using some sort of non-propellant based engine (and thus no fuel), or the engines are not going to interfere with people's sleep. Rocket engines are fired very rarely, you don't have the fuel (or need) to be thrusting all the time (although if you can, it's one way to do gravity). With a non-propellant engine, you could thrust to accelerate towards your destination, then half-way there turn around and thrust to slow down, and get there faster than if you just did one burn and then "coasted" to your destination, but the latter is the way that every engine that's been seriously discussed does it, and so you're going to have true engine noise maybe 10 minutes out of every trip.

GungHo
2013-09-19, 08:54 AM
I can't tell if you're looking for science advice, business process advice, or what. You don't seem to have any actual questions about aeronautics or aerospace embedded anywhere, nor any real aerospace challenges presented.

Geordnet
2013-09-19, 02:25 PM
Add me to the list of confused engineers. The only thing I'm really qualified to give is hard science advice, but I'm sorry to say that there really isn't anything right about the ship from that perspective: it just plain wouldn't work in real life. But as others have pointed out, it's perfectly fine in only moderately-hard sci-fi. (I would personally put it at Firefly-level hardness.)

The best advice I can give you is to look up the sandbox rocketry simulator game "Kerbal Space Program" if you want to get an idea how space really works.


If you actually want my destructive criticism, though, here it is:
For starters, space travel is so expensive that "mobile repair ships" don't make economic sense. Either establish a permanent base in the area, or send a replacement.

Secondly, the #1 hardest thing to transport in space is people. Literally tons of life support systems and radiation shielding is needed for just a handfull of crewmen, not to mention the engineering challanges of fending off muscle/bone atrophy and ordinary cabin fever during the multi-year voyages.
The point is: everything should be controlled remotely. The only reason for humans to ever be aboard a ship is if moving humans is part of that ship's mission.

Even if there were humans aboard, they wouldn't have to worry about the noise of the engine interrupting their sleep. The most efficient (fuel-wise) method of space travel involves short, minutes-long "burns" separated by months-long cruises. Besides, any thruster with a low enough fuel (propellant) consumption to be able to run constantly would necessarily be too low-power to wake disturb sleep.

Oh, and you didn't mention any propellant tanks. Propellant/fuel should make up ~80% of the ship's mass. :smalltongue:

Trekkin
2013-09-19, 03:24 PM
KSP might work; I'd be remiss if I didn't also bring up Orbiter, though, if you want more numbers.

That aside, I'm not quite sure on what basis we're supposed to be looking at the viability of the design. The only thing that really jumps out at me is the conflation of the engine with the ship's power supply -- at least, that's why I'm assuming the engine is on constantly. Usually, the part of the spacecraft responsible for moving it around is separate from the part keeping the lights and air on; here it sounds like they're the same system, which is fine but messes with the hardness a bit.

The problems inherent to moving humans have already been pointed out; I'd just add that the crew complement seems a bit redundant.

Really, we need to know how the ship is supposed to work in order to comment on how realistic it is. What does the engine run on? How does the G-Stabe work?

Toy Killer
2013-09-19, 08:07 PM
If you actually want my destructive criticism, though, here it is:
For starters, space travel is so expensive that "mobile repair ships" don't make economic sense. Either establish a permanent base in the area, or send a replacement.

Secondly, the #1 hardest thing to transport in space is people. Literally tons of life support systems and radiation shielding is needed for just a handfull of crewmen, not to mention the engineering challanges of fending off muscle/bone atrophy and ordinary cabin fever during the multi-year voyages.
The point is: everything should be controlled remotely. The only reason for humans to ever be aboard a ship is if moving humans is part of that ship's mission.

Even if there were humans aboard, they wouldn't have to worry about the noise of the engine interrupting their sleep. The most efficient (fuel-wise) method of space travel involves short, minutes-long "burns" separated by months-long cruises. Besides, any thruster with a low enough fuel (propellant) consumption to be able to run constantly would necessarily be too low-power to wake disturb sleep.

Oh, and you didn't mention any propellant tanks. Propellant/fuel should make up ~80% of the ship's mass. :smalltongue:

This is what I was looking for. I plan on advertising this game out around my college campus and didn't want it to devolve into an hour long aerospace lecture dissecting the 'realism' of the game. I'm looking for a 'baby's first project' for my first graphic novel and figured this would be a good way to A)Get a story that people will, at least immediately, understand with only criticisms of fridge logic, and B) Get me use to working with people on a story, rather then ignoring peoples advice on how the story should go.

Problem is, for all my love of drawing gunk ridden matrix/Geiger-esque techonology and gore, I don't really know much about actual space travel. I avoided trying to discuss the ship's mechanics, since i use to work with an a gentleman who dropped out of his aeronautical engineering degree and learned quickly I don't know jack about how space 'Works'. Further more, the point of the labor being economically unfeasible is partially the point. I mentioned that their is a ban on AI surpassing a certain point of processing power (For the record, I'm also technologically challenged, I don't know if 4 terrabytes is any kind of limitation), which was supposed to imply that they needed men on the ground.

I also recalled communication in space being remarkably difficult to maintain when you start dealing with cosmic numbers, so I figured they would approach it the easiest method available by having underpaid, overworked crews go site to site and manually work on the drones.

Sorry for not being clear, I guess, I didn't know what I wanted to ask for?

Mando Knight
2013-09-20, 12:18 AM
Problem is, for all my love of drawing gunk ridden matrix/Geiger-esque techonology and gore, I don't really know much about actual space travel. I avoided trying to discuss the ship's mechanics, since i use to work with an a gentleman who dropped out of his aeronautical engineering degree and learned quickly I don't know jack about how space 'Works'.
Space works by doing nothing. All you really have out there are gravity and your rocket. And horrible death rays coming off of those hyper-gigantic balls of fire that everything happens to be flying around.

I also recalled communication in space being remarkably difficult to maintain when you start dealing with cosmic numbers, so I figured they would approach it the easiest method available by having underpaid, overworked crews go site to site and manually work on the drones.
That's like saying "you only have dial-up, so the easiest way to contact someone on the other side of the continent is to ride a horse out there yourself."

Trekkin
2013-09-20, 02:50 AM
That's like saying "you only have dial-up, so the easiest way to contact someone on the other side of the continent is to ride a horse out there yourself."

This. If you have FTL travel -- and it sounds like you do -- you also have FTL communications without manned ships. Just load the data and a transmitter onto a robot. Depending on the design of your FTL drive, it may even be most efficient to make it a series of one-way robots.

If you want a concise explanation of space as it relates to the design of spacecraft, look at the Tsiolkovsky rocket equation. The smaller you can get your payload (like a radio and a flash drive versus six people), the less fuel you need to carry, and everything lightens and cheapens up exponentially.

Oh! I thought of something else, if we can still offer criticism: It sounds like the whole ship lands on the planet to deal with the drones. Conventional wisdom would dictate at least two ships: an interstellar/interplanetary one moving a separatable lander around. Otherwise you're dragging your stardrive around to places where you presumably don't want to turn it on, and that's a bit of a waste. Really, there could be a series of landers, or at least a reconfigurable one, depending on the planet in question.

Telok
2013-09-20, 04:06 AM
I've got to plug Atomic Rockets (http://www.projectrho.com/public_html/rocket/crossindex.php) at Project Rho. It's a technical assistance guide for SF writers. Scroll down to the bottom of the page for the topic list.

Sir_Mopalot
2013-09-20, 04:42 AM
I've got to plug Atomic Rockets (http://www.projectrho.com/public_html/rocket/crossindex.php) at Project Rho. It's a technical assistance guide for SF writers. Scroll down to the bottom of the page for the topic list.

I love that website, just keep in mind that there's a perfectly good reason that most sci-fi stories are softer sci-fi than what he's talking about. Space combat will simply not be as interesting as we'd like it to be, so to make it interesting, you're stepping away from rock-hard sci-fi.

Adoendithas
2013-09-20, 07:25 AM
I love that website, just keep in mind that there's a perfectly good reason that most sci-fi stories are softer sci-fi than what he's talking about. Space combat will simply not be as interesting as we'd like it to be, so to make it interesting, you're stepping away from rock-hard sci-fi.

As an example, try looking at the end of Protector by Larry Niven. That describes a battle in space without FTL travel, and is so incredibly tedious the book doesn't lose much if you skip to the end.

Toy Killer
2013-09-20, 10:32 AM
So, For the setting i have in place, I probably should just go with a softer sf? Its ultimately nonsense in a hard scifi for a crew based ship to travel to these work sites?

Deophaun
2013-09-20, 10:56 AM
This. If you have FTL travel -- and it sounds like you do -- you also have FTL communications without manned ships. Just load the data and a transmitter onto a robot. Depending on the design of your FTL drive, it may even be most efficient to make it a series of one-way robots.
That's assuming FTL doesn't do something wonky to mess up robots yet leaves carbon-based life alone.

Mando Knight
2013-09-20, 01:48 PM
That's assuming FTL doesn't do something wonky to mess up robots yet leaves carbon-based life alone.
Then the carbon-based life wouldn't be safe running FTL either, unless their engineer is used to rebuilding the system after every jump.

The Glyphstone
2013-09-20, 02:13 PM
Biotech/organic ships? Soft sci-fi, indeed.:smallsmile:

Adoendithas
2013-09-20, 04:14 PM
You could use a handwave like Niven did in his later works: the "mass pointer" device is the only way to navigate in hyperspace, but it's inherently psionic and can't be read by a machine.

Mastikator
2013-09-20, 05:36 PM
That's assuming FTL doesn't do something wonky to mess up robots yet leaves carbon-based life alone.

Wouldn't that also mess up the ship and life support, which messes up the carbon based life.

I agree with the "put a few petabytes of data on a flash drive and put that on the lightest fastest probe and charge by the space, send every day/week/month/hour/whatever". (Assuming FTL civilization and not just one ship trekking through the stars).

Toy Killer
2013-09-20, 06:40 PM
If you have FTL travel -- and it sounds like you do -- you also have FTL communications without manned ships. Just load the data and a transmitter onto a robot. Depending on the design of your FTL drive, it may even be most efficient to make it a series of one-way robots.
Well, no, because they have limited information on the drones. While the drones can report something is wrong, and maybe what the general of what they need, they aren't able to fix it themselves with the current limitations of their AI. The big point of sending out people is that they are drastically more capable of analyzing a situation and taking care of the situation regardless with what the problems present themselves with, especially with people educated on the manufacturing, programing and wetware development of drones.

A big part of the challenge of the job is the unexpected nature of things. Even if you were to deploy droids to fix other droids, they would have to be tailor made to the situations they have to address. Even if you did, it's not certain that they would still be relevant to fix the issues by the time they arrived.


If you want a concise explanation of space as it relates to the design of spacecraft, look at the Tsiolkovsky rocket equation. The smaller you can get your payload (like a radio and a flash drive versus six people), the less fuel you need to carry, and everything lightens and cheapens up exponentially.

Oh! I thought of something else, if we can still offer criticism: It sounds like the whole ship lands on the planet to deal with the drones. Conventional wisdom would dictate at least two ships: an interstellar/interplanetary one moving a separatable lander around. Otherwise you're dragging your stardrive around to places where you presumably don't want to turn it on, and that's a bit of a waste. Really, there could be a series of landers, or at least a reconfigurable one, depending on the planet in question.

Understood, but I'd like the players to not have access to a second space capable ship. Its for the game dread, and I want to limit there options available.

Rakaydos
2013-09-20, 07:04 PM
As far as landers vs intersteller ships, you out to check out the Airship to Orbit (http://www.jpaerospace.com/atohandout.pdf) concept.

The concept, if it works (and there are technical specialists who have said that the concept is so close to the edge that arnt sure which side it's on) works HUGE- lifting payloads of hundreds of tons to orbit for a price comparable to a space elevator, without the engineering infrastructure.

Reversing the concept, you have an intersteller starship deploy one for atmospheric work, with lower altitude designs deployed from the "upper atmo mothership."

Trekkin
2013-09-20, 09:33 PM
If you wanted something a little less extreme (and as technically fascinating as ATO is, it's a lot to explain) you could always just leave just the stardrive parts in orbit as an unmanned chunk of electronics. Then they still only have one ship, in that they only have one set of life-support and maneuvering systems. It's much less safe, but not quite impossible, and you could just say the attitude control system on the stardrive is so dodgy it's effectively dead in space.

Or you could simply have a very lightweight, non-propellant-using stardrive. Very soft science fiction, but doable.

Deophaun
2013-09-20, 09:46 PM
Then the carbon-based life wouldn't be safe running FTL either, unless their engineer is used to rebuilding the system after every jump.

Wouldn't that also mess up the ship and life support, which messes up the carbon based life.
You are making heavy assumptions here; namely that the systems necessary to guide a ship and automate its FTL run require the same technology as the engines, power generation, and life support. Vernor Vinge would politely disagree (http://en.wikipedia.org/wiki/A_Fire_Upon_the_Deep).

FTL is basically magic dressed up in the clothes of a scientist. That gives you a lot of freedom as to whatever effects it will have.

Mando Knight
2013-09-20, 10:52 PM
You are making heavy assumptions here; namely that the systems necessary to guide a ship and automate its FTL run require the same technology as the engines, power generation, and life support. Vernor Vinge would politely disagree (http://en.wikipedia.org/wiki/A_Fire_Upon_the_Deep).

If the FTL drive messes up robots, then it messes up sufficiently similar systems, i.e. computer-controlled mechanical devices. Unless all of the ship's systems are made of something that is fundamentally more like the organics than like the drones (or possibly too simple to be messed up by the FTL drive instead), the ship's systems are messed up just as much by the FTL as any drone.

Deophaun
2013-09-20, 11:21 PM
If the FTL drive messes up robots, then it messes up sufficiently similar systems, i.e. computer-controlled mechanical devices.
I am well aware that you are making assumptions consistent with how technology is today, and not how technology could/would develop if the problem I indicated were true.

I await your response where you explain how something like dumb mechanical controls for these systems are more preposterous and push the boundaries of suspension of disbelief more than the physical impossibility that is the FTL drive.

Rakaydos
2013-09-20, 11:32 PM
For reference, in one of David Drake's Scifi series (the Daniel Leary books) a single leaked EM signal, however tiny, will cause a ship to be lost in FTL forever. Therefor, managing the external FTL rigging is done by hydraulics and comm-less spacesuits. All the computers are inside faraday cages.

Mastikator
2013-09-21, 08:43 AM
You are making heavy assumptions here; namely that the systems necessary to guide a ship and automate its FTL run require the same technology as the engines, power generation, and life support. Vernor Vinge would politely disagree (http://en.wikipedia.org/wiki/A_Fire_Upon_the_Deep).

FTL is basically magic dressed up in the clothes of a scientist. That gives you a lot of freedom as to whatever effects it will have.

Yeah I'm assuming there are things you can't protect robots from that humans are not subject to. At first I though heavy magnetic fields, but even a Faraday Cage could solve that problem. To be honest I can't think of anything. Compared to robots in space, humans are very squishy.

The only thing that wouldn't be hurt by something that would mess with electronics would be a chemical rocket. Which is extremely inefficient for interstellar travel, you're much better off with an electrostatic ion propulsion drive (which does use electricity). If anything's gonna mess with a robot it's also gonna mess with the engines.

Edit-
I've spent a lot of time doing two things, thinking about this sort of stuff and playing Kerbal Space Program. And there's two things I've discovered:
If you're going further than the moon, don't use chemical rockets. You use chemical rockets to get into orbit, they're awesome for getting you off the planet, they're bad for getting you to the next planet.
A space elevator would be a game-changer. A civilization is NEVER going to be a space civilization without a space elevator. With a space elevator you can transport things into space without transporting the fuel into space that it costs to transport into space. Currently ~99% of the mass of any ship going into space is the fuel that it takes to get the payload into orbit. If you can get into orbit without having to take the fuel with you then you can save 80% of the energy and mass. This would make things like asteroid mining economical.

Deophaun
2013-09-21, 10:03 AM
Yeah I'm assuming there are things you can't protect robots from that humans are not subject to.
Which, considering the premise is that there is something about FTL travel that messes up electronics, but not biologicals, is an assumption that was already stated to be wrong.

At first I though heavy magnetic fields, but even a Faraday Cage could solve that problem. To be honest I can't think of anything.
Because the idea that someone would use a fictitious force to introduce a new complication is unknown in the field of science fiction.

Compared to robots in space, humans are very squishy.
Is that why human brains function just fine in environments that would wreck the computer you posted this statement from? There's a reason you don't have spacecraft running on an Intel Core i7. Throw in research on things like tardigrades paying off by giving us heightened resistance to ionizing radiation, and yeah, I can see plenty of environments where humans would work but advanced electronics would not.

GM.Casper
2013-09-21, 10:35 AM
Um, there is a very good reason to send humans to other stars- because, barring strong AI, they are needed to solve complex problems. Dumb robots have limits, and without FTL-comms, remote control is out too. Assuming FTL travel is cheap (and since its powered by magic anyway, might as well make it cheap), there is no reason you would not be sending human crews out.

In fact, if your FTL drive goes directly from a planets orbit to another planet, you don't need any advanced thrusters either. If some genius invented a light and low energy FTL drive tomorrow, you could add it to a spaceplane and go explore.

Mando Knight
2013-09-21, 11:43 AM
I am well aware that you are making assumptions consistent with how technology is today,There is no other starting point except for pure fantasy, which would allow for any number of otherwise unreasonable assumptions.

I await your response where you explain how something like dumb mechanical controls for these systems are more preposterous and push the boundaries of suspension of disbelief more than the physical impossibility that is the FTL drive.
Simple life support may allow for non-computerized control, but to fully automate a spacecraft, including navigation, without computers? Preposterous, unless you allow for technology that could be applied to the robots equally to the starship, if in lesser scale.

FTL is a magical plot device, yes, but if you turn the automation systems into another magical plot device that is fully compatible with your FTL drive, but have robots (which are simply self-contained automated systems) not using the magical automation system as well without some valid reason (old robots dispersed in sleeper ships without recently-developed tech that is installed in the FTL ships, or something) is absurd.

One is an impossibility made possible and a general convention for the genre, the other is a correction for an impossibility that is then applied inconsistently. Inconsistency in technological ability is more nagging to me at least than mere impossibility.

There's a reason you don't have spacecraft running on an Intel Core i7.And it's probably not what you're thinking. Rad-hardening is possible for computer systems, though it lags behind unhardened systems.
Throw in research on things like tardigrades paying off by giving us heightened resistance to ionizing radiation, and yeah, I can see plenty of environments where humans would work but advanced electronics would not.
That kind of organic self-engineering is further beyond our capabilities than making a highly resistant computer system, and I highly suspect that the reasons why tardigrades are capable extremophiles are not something you can "port over" to humans.

Mastikator
2013-09-21, 11:47 AM
Which, considering the premise is that there is something about FTL travel that messes up electronics, but not biologicals, is an assumption that was already stated to be wrong. What something?


Because the idea that someone would use a fictitious force to introduce a new complication is unknown in the field of science fiction.Fictitious force? Here I was on the assumption that FTL doesn't involve "magic" but rather something like an Alcubierre drive.


Is that why human brains function just fine in environments that would wreck the computer you posted this statement from? There's a reason you don't have spacecraft running on an Intel Core i7. Throw in research on things like tardigrades paying off by giving us heightened resistance to ionizing radiation, and yeah, I can see plenty of environments where humans would work but advanced electronics would not.
I'm not saying that there aren't environments that electronics can't handle but human brains can. I'm saying that there aren't spaceships that can have their electronics out of function but still perform interstellar travel while maintaining life support. Fictitious magic forces or no.

Rakaydos
2013-09-21, 12:10 PM
The Abercrombi Drive is strictly volume limited- Recent optimizations got the energy requited for a 10m (that's only 30 feet across!) warp field to drop below the energy requirement of JUPITER TURNED TO ANTIMATTER. Bigger fields, by definition need more energy.

Now, using the Abercromb Warp drive to transport, say, a Quantum-Entanglement device, (either a scifi stargate if you want people, or just a comunicator if drones are fine) would be a fine way to explore the stars.

(also, it is my personal headcanon theory that the compressed space in front of an Abercromb Warp drive a a high enough C+ would compress intersteller hydrogen AND cosmic ray count enough to generate an ongoing Muons-Catalised Fusion (http://www.ask.com/wiki/Muon-catalyzed_fusion?o=2800&qsrc=999) event while the drive is active.

Deophaun
2013-09-21, 01:54 PM
There is no other starting point except for pure fantasy, which would allow for any number of otherwise unreasonable assumptions.
Like FTL.

Simple life support may allow for non-computerized control, but to fully automate a spacecraft, including navigation, without computers? Preposterous, unless you allow for technology that could be applied to the robots equally to the starship, if in lesser scale.
Where in the hell did the bold part come from? The entire purpose of this exercise is to make it so people are necessary, and you come out with full automation? What. The. Hell?

And it's probably not what you're thinking. Rad-hardening is possible for computer systems, though it lags behind unhardened systems.
Yup. Because it's a fact that by the time FTL is invented, it will not produce levels of radiation that will exceed our ability to harden our systems against.

I also note that you seem to believe in telepathy. Unfortunately, your display here is just further evidence that that doesn't exist either.

That kind of organic self-engineering is further beyond our capabilities than making a highly resistant computer system, and I highly suspect that the reasons why tardigrades are capable extremophiles are not something you can "port over" to humans.Yes. In science fiction, it has been proven that technology must proceed along a certain vector: kind of like a tech tree in a video game, but less tree and more poll. Any deviation from this poll, where, say, the biological sciences out perform mechanical sciences, is ridiculous. Everyone knows that, otherwise Star Trek wouldn't work!

What something?
The plotian field, for instance. Or the excessive build up of narrative decay.

Fictitious force? Here I was on the assumption that FTL doesn't involve "magic" but rather something like an Alcubierre drive.
Which relies on the magic of exotic matter. You can do pretty much anything with that stuff. It's why unobtanium is the solution to just about every technical problem.

I'm not saying that there aren't environments that electronics can't handle but human brains can. I'm saying that there aren't spaceships that can have their electronics out of function but still perform interstellar travel while maintaining life support.
I'll do you one better: there aren't spaceships that can perform interstellar travel.

Now, you were saying what?

Rakaydos
2013-09-21, 02:15 PM
I'm not saying that there aren't environments that electronics can't handle but human brains can. I'm saying that there aren't spaceships that can have their electronics out of function but still perform interstellar travel while maintaining life support. Fictitious magic forces or no.

Apollo 13 made a multi-day trip around the moon with all power on the command module turned off. While they did have problems with the filters that was related to not having enough in the 2 man lander for the 3 man crew (and was solved by duck tape, if the dramatization is at all accurate)

Adoendithas
2013-09-21, 03:24 PM
Apollo 13 made a multi-day trip around the moon with all power on the command module turned off. While they did have problems with the filters that was related to not having enough in the 2 man lander for the 3 man crew (and was solved by duck tape, if the dramatization is at all accurate)

It's somewhat accurate, but duct tape was used.

If you want something somewhat realistic without using the bizarre Alcubierre warp drive, you could postulate an additional spatial dimension along which FTL ships can travel. "A Wrinkle in Time" has the best explanation of this, but in essence you could bend space using that additional dimension and create "gaps" through the fold to move quickly through. An additional spatial dimension can get you almost any other "magical" effect you need, from immovable objects to portals to teleportation to invisibility.

Mando Knight
2013-09-21, 04:32 PM
Where in the hell did the bold part come from? The entire purpose of this exercise is to make it so people are necessary, and you come out with full automation? What. The. Hell?
I misrepresented my point. There will be areas that will need to be relatively highly automated. Things like astronomic mapping, since any live data you receive barring FTL communications will be years out of date.

Yup. Because it's a fact that by the time FTL is invented, it will not produce levels of radiation that will exceed our ability to harden our systems against.
Then we sure as hell had better not put humans in those ships.

Yes. In science fiction, it has been proven that technology must proceed along a certain vector: kind of like a tech tree in a video game, but less tree and more poll. Any deviation from this poll, where, say, the biological sciences out perform mechanical sciences, is ridiculous. Everyone knows that, otherwise Star Trek wouldn't work!
Not what I meant. I mean that tardigrade research won't directly benefit human physiology because part of what makes it resilient to adverse conditions is its relatively extremely simplified biology which requires things that simply won't work at the human scale (such as using spiracles for respiration). Innate rad-hardening may be useful if its genetic self-repair can be understood and applied to larger beings.

Rakaydos
2013-09-21, 05:17 PM
To make bringing humans make sence, there needs to be a reason that bringing humans is NO WORSE than bringing a purely automated ship.

There's a couple ways to go about this. Cryo is one classic option- get rid of life support requirements and ship the crew as cargo until they reach their destination.

Another possibility is having the FTL ship as merely the vehical for a faster form of transport, such as a mini-wormhole or stargate. While obliviously more technically demanding, (and possibly silly sounding) "dragging" a wormhole mouth with a Abercrombe warp drive lets you keep your cargo (and for that matter, energy requirements and fuel) someplace else while the ship does the moving.

A third option is to abandon the argument of humans vs machines- and make the characters uploaded personalities, operating robotic "bodies."

Deophaun
2013-09-21, 07:17 PM
Things like astronomic mapping, since any live data you receive barring FTL communications will be years out of date.
Or you have better detection at the point of origin, and better models, and so all the mapping is done for you and projected accurately into the present. Unless quantum fluctuations have a significant impact on orbital bodies over almost no time at all (speaking in galactic timeframes), perfectly within the bounds of science.

Once local, RADAR works with vacuum tubes. Or you flip off the FTL drive and then unpack the supercomputer-backed sensor suite to get a better look at your surroundings. Really easy hurdles to clear.

Then we sure as hell had better not put humans in those ships.
Unless it is easier to harden humans against radiation than it is electronics.

Do try to keep up with the discussion.

I mean that tardigrade research won't directly benefit human physiology because part of what makes it resilient to adverse conditions is its relatively extremely simplified biology which requires things that simply won't work at the human scale (such as using spiracles for respiration).
Well, then it's a good thing that the tardigrade was merely an example, and not something that any part of my argument hinged upon.

Innate rad-hardening may be useful if its genetic self-repair can be understood and applied to larger beings.
The only relevant question is: is there a physical law or theory that requires human-scale biological life to be susceptible to radiation. I haven't come across anything like that, and if such a law or theory does not exist, that makes it an engineering problem (on par with cryogenic sleep), not a science problem (perpetual motion machines).

Similarly: is there a scientific law or theory that requires computers to do any of the tasks on an interstellar spaceship? Well, there isn't. That, again, makes it an engineering problem. As long as science allows it, all engineering problems need are resources and know how, which are the easiest things to provide in fiction.

Mastikator
2013-09-21, 07:33 PM
Apollo 13 made a multi-day trip around the moon with all power on the command module turned off. While they did have problems with the filters that was related to not having enough in the 2 man lander for the 3 man crew (and was solved by duck tape, if the dramatization is at all accurate)

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Rakaydos
2013-09-21, 07:39 PM
intersteller

Name a manned flight that has gone FURTHER than the Apollo program.

Mando Knight
2013-09-21, 08:18 PM
Once local, RADAR works with vacuum tubes. Or you flip off the FTL drive and then unpack the supercomputer-backed sensor suite to get a better look at your surroundings. Really easy hurdles to clear.
If you're allowed to carry a powered-down computer in a shielded case while running on vacuum tubes or switches on standby, it would be quite possible to configure a hybrid computer system that could shut its microchips off while in FTL and turn them back on afterward.

Unless it is easier to harden humans against radiation than it is electronics.
It very much isn't, barring extreme advances in biological engineering. All we can currently do for humans is provide shielding (which would benefit organics and electronics equally). Electronics are comparatively already rad-resistant compared to humans (50-100 Gy vs 6-8), and current rad-hardened systems are at least 10 times that (the RAD750 CPU is rated at 2-10 kGy max dose).

Rakaydos
2013-09-21, 08:49 PM
If I was designing a ship that could not use electrical systems during FTL...

First off, Cryotubes for the crew, on basically a glorified eggtimer- stops the brainwaves of the organic crew from interfering (or being interfered by) the FTL drive.

Flight calculations are handled by a dedicated Babbage engine- bulky and not reprogramable, but sufficent to the task with enough mechanical power.

Mechanical power can be generated by Sterling Engines around a Nuclear Decay heat source.

Sir_Mopalot
2013-09-22, 02:41 AM
Flight calculations are handled by a dedicated Babbage engine- bulky and not reprogramable, but sufficent to the task with enough mechanical power.

Mechanical power can be generated by Sterling Engines around a Nuclear Decay heat source.

That is deliciously steampunk. It's rare for steampunk to be combined with anything close to FTL travel, especially "hard" FTL.

Tavar
2013-09-22, 02:56 AM
Name a manned flight that has gone FURTHER than the Apollo program.

That's like saying that because someone can swim across the English Channel, swimming around the entire world is feasible.

TuggyNE
2013-09-22, 03:25 AM
Flight calculations are handled by a dedicated Babbage engine- bulky and not reprogramable, but sufficent to the task with enough mechanical power.

Mechanical power can be generated by Sterling Engines around a Nuclear Decay heat source.

How did I not see this sooner? Oh, edits.

Anyway, yeah, impressive. However, simple vacuum tubes are at once far more powerful and far smaller than mechanical computers, and are fairly radiation resistant (at least in comparison to transistors of all stripes), so it's possible that those would be good enough to avoid the Magitech FTL Death Rays of DoomTM. Navigation calculations in space are actually quite involved, so I'm not sure a Babbage engine would really be able to manage with anything under a few hundred tons of tiny Swiss gears.

Also, it's Stirling, not Sterling. One of my favorite devices, can't have wrong names going around!

Eric Tolle
2013-09-22, 04:51 AM
You know, it should be within or technical capabilities today to make cargo ships that don't require crew. Why don't they do that?

TuggyNE
2013-09-22, 06:12 AM
You know, it should be within or technical capabilities today to make cargo ships that don't require crew. Why don't they do that?

Liability.

Toy Killer
2013-09-22, 10:53 AM
So, is there any kind of consensus on what the specs of this ship is?

I'm sorry, I'm not going to lie, most of this is going right over my head...

Trekkin
2013-09-22, 02:33 PM
So, is there any kind of consensus on what the specs of this ship is?

I'm sorry, I'm not going to lie, most of this is going right over my head...

There are indeed. On point of fact, there are multiple consensuses.

I think it might help if we had a list of what the ship had to do to fill its story role, since we could work back to some form of engineering from there. Right now we're just talking about FTL in general, especially how to constrain an FTL drive to mandate the presence of crew.

If we knew how long you wanted it to stay in space between re-provisioning, that would be a good start.

warty goblin
2013-09-22, 02:59 PM
The people who are going to nitpick your science fiction are going to nitpick your science fiction. They will do this because they like nitpicking science fiction, probably because they enjoy feeling smart. There's no point in trying to make them happy by adding things they think are realistic or reasonable, because each and every one will have different ideas about what is realistic or reasonable. Appease one, and the other will give you a long explanation of how that's terrible and inconsistent and wasn't this supposed to be hard science fiction. You are now caught between a Scylla and Charybdis of terrible nerd habits, and there's no escape. So, to confuse a classical metaphor, don't follow the siren song of appeasement in the first place.

If they start derailing the game, I suggest explaining that if they don't want play the game you are offering, they can leave. If they do want to play, they can stop mewling, accept that the word fiction is in science fiction for a reason, and play. That part is up to them, but you put in the actual work of making the setting and the plot and the NPCs, and aren't redoing it now.

The Grue
2013-09-22, 03:00 PM
So, is there any kind of consensus on what the specs of this ship is?

I'm sorry, I'm not going to lie, most of this is going right over my head...

One of the dangers of giving aerospace engineers an open license to comment, I suppose. :smallbiggrin:

Mastikator
2013-09-22, 03:47 PM
If I was designing a ship that could not use electrical systems during FTL...

First off, Cryotubes for the crew, on basically a glorified eggtimer- stops the brainwaves of the organic crew from interfering (or being interfered by) the FTL drive.

Flight calculations are handled by a dedicated Babbage engine- bulky and not reprogramable, but sufficent to the task with enough mechanical power.

Mechanical power can be generated by Sterling Engines around a Nuclear Decay heat source.
Being able to achieve FTL without electronics would completely undermine the need for aerospace engineers to comment in this thread. Just go with Dragon uses magic and takes people with it on awesome fun joy ride to the moon and back.

Starshade
2013-09-22, 04:43 PM
To make bringing humans make sence, there needs to be a reason that bringing humans is NO WORSE than bringing a purely automated ship.


Well, lets say, what if AI Research have not made as much progress as in scifi Movies, I don't mean making the AI bad is needed, just, perhaps not up to biological entities abilities to improvise and do completely original stuff.
And, limit FTL communication somehow, so remote repairing isn't totally reliable.

Toy Killer
2013-09-22, 04:59 PM
Well, lets say, what if AI Research have not made as much progress as in scifi Movies, I don't mean making the AI bad is needed, just, perhaps not up to biological entities abilities to improvise and do completely original stuff.
And, limit FTL communication somehow, so remote repairing isn't totally reliable.

That was the premise, AI is limited to very raw structure, but it is improving within it's own boundaries, leaving the business in a sticky point of not wanting to invest in it's people's well being, but still needing them for the time being.

The communication would take too long for a reliable repair to be done on planet side and updates are needed from time to time.

They will be traveling on these circuits for approximately 1 to 2 months at a time. About a day's travel inbetween 20-40 work sites, with work taking up most of the day

I honestly didn't think it would be this big of an issue.

The Grue
2013-09-22, 05:01 PM
That was the premise, AI is limited to very raw structure, but it is improving within it's own boundaries, leaving the business in a sticky point of not wanting to invest in it's people's well being, but still needing them for the time being.

The communication would take too long for a reliable repair to be done on planet side and updates are needed from time to time.

They will be traveling on these circuits for approximately 1 to 2 months at a time. About a day's travel inbetween 20-40 work sites, with work taking up most of the day

I honestly didn't think it would be this big of an issue.

It's only an issue if you want to present a realistic depiction of space travel. Which you don't have to do, by the way. Star Trek never did, and it turned out alright.

Mando Knight
2013-09-22, 07:30 PM
It's only an issue if you want to present a realistic depiction of space travel. Which you don't have to do, by the way. Star Trek never did, and it turned out alright.

Neither does Star Wars.

...Actually, there aren't very many Sci-fi series out there that don't apply a Clarke's 3rd Law Engine for its main thruster.

Worrying about how "real" your spaceship is will take the fun out of it unless you like teaching yourself math. (If that is something you like to do, David A. Vallado's Fundamentals of Astrodynamics and Applications would be a good source for how space works and what we can do with it now.)

Instead, try to apply your magical technology consistently with itself. AI might be limited on a critical/conceptual thinking level, but it would still be a valuable tool for quickly mapping out and precisely executing FTL jumps.

Also, remember that fuses exist. Probably 75% of all injuries and deaths onboard the Enterprise could have been avoided if electroplasma conduits came with fuses.

Rakaydos
2013-09-22, 07:39 PM
Actually, lately I've been rather taken by the idea I threw together earlier- the Abercrombi Warpdrive/Wormhole hybrid. Similar technical requirements for both techs, solves the power and cargo space issues for the warpdrive, solves the "1 destination" issue or wormholes.

Mando Knight
2013-09-22, 08:28 PM
Actually, lately I've been rather taken by the idea I threw together earlier- the Abercrombi Warpdrive/Wormhole hybrid. Similar technical requirements for both techs, solves the power and cargo space issues for the warpdrive, solves the "1 destination" issue or wormholes.

Alcubierre, not Abercrombie. Warp drives don't run on designer jeans.

The Grue
2013-09-22, 08:58 PM
...Actually, there aren't very many Sci-fi series out there that don't apply a Clarke's 3rd Law Engine for its main thruster.

Revelation Space does a good job in that regard. Takes relativity and time dilation square in the nose and presents an interstellar civilization that is actually pretty okay with being limited to just-shy-of lightspeed.

Well, until the third book when he starts introducing inertial suppression, cryo-arithmetic engines and weakly acausal weapons but eh.

TuggyNE
2013-09-22, 09:50 PM
Alcubierre, not Abercrombie. Warp drives don't run on designer jeans.

Sure they do! You just have to go down the Pants of Space the other way. :smalltongue:

Adoendithas
2013-09-22, 09:54 PM
Also, remember that fuses exist. Probably 75% of all injuries and deaths onboard the Enterprise could have been avoided if electroplasma conduits came with fuses.

Surge protectors and UPSs as well, so Skotty wouldn't need to keep replacing the stuff that blows up.

Sir_Mopalot
2013-09-23, 03:22 AM
I think Mando Knight hit on the most important thing. 99% of sci-fi relies upon at least one Big Lie, and the key to making it good sci-fi is ensuring that Magic A is Magic A (http://tvtropes.org/pmwiki/pmwiki.php/Main/MagicAIsMagicA). Make something up to explain away whatever you're trying to introduce into your story, and then make up rules for it. Then stick to those rules. That's the way to do it. My first thought is that while FTL travel is possible, FTL communications isn't, using whatever FTL engine you come up with. This means that, failing a strong AI, there have to be humans inside light-speed comms range. There. As long as you don't need (or use) FTL comms in your story, problem solved, and your universe stays internally consistent.

The Grue
2013-09-23, 09:21 AM
I think Mando Knight hit on the most important thing. 99% of sci-fi relies upon at least one Big Lie, and the key to making it good sci-fi is ensuring that Magic A is Magic A (http://tvtropes.org/pmwiki/pmwiki.php/Main/MagicAIsMagicA). Make something up to explain away whatever you're trying to introduce into your story, and then make up rules for it. Then stick to those rules. That's the way to do it. My first thought is that while FTL travel is possible, FTL communications isn't, using whatever FTL engine you come up with. This means that, failing a strong AI, there have to be humans inside light-speed comms range. There. As long as you don't need (or use) FTL comms in your story, problem solved, and your universe stays internally consistent.

Real-time FTL communication anyway. If you want no FTL communication whatsoever, you then need a reason why it's not practical to fill a tin can with stored messages, duct-tape an FTL drive to it, and kick it through subspace to a prearranged pickup location.

ReaderAt2046
2013-09-23, 12:26 PM
Apollo 13 made a multi-day trip around the moon with all power on the command module turned off. While they did have problems with the filters that was related to not having enough in the 2 man lander for the 3 man crew (and was solved by duck tape, if the dramatization is at all accurate)

IIRC, they could only do that because they still did have power in the lunar lander module. They essentially used that as a surrogate spaceship for most of the flight.

ReaderAt2046
2013-09-23, 12:30 PM
I think Mando Knight hit on the most important thing. 99% of sci-fi relies upon at least one Big Lie, and the key to making it good sci-fi is ensuring that Magic A is Magic A (http://tvtropes.org/pmwiki/pmwiki.php/Main/MagicAIsMagicA). Make something up to explain away whatever you're trying to introduce into your story, and then make up rules for it. Then stick to those rules. That's the way to do it. My first thought is that while FTL travel is possible, FTL communications isn't, using whatever FTL engine you come up with. This means that, failing a strong AI, there have to be humans inside light-speed comms range. There. As long as you don't need (or use) FTL comms in your story, problem solved, and your universe stays internally consistent.

In the Firebird Trilogy by Kathy Tyers (great series, by the way), they actually have something like this. Ships can travel FTL by moving through "slipspace", but slipspace communications have a fairly limited range before they revert to realspace. So you can have FTL comms in-system, but for interstellar travel you have to use messenger systems.

Sir_Mopalot
2013-09-23, 02:40 PM
Real-time FTL communication anyway. If you want no FTL communication whatsoever, you then need a reason why it's not practical to fill a tin can with stored messages, duct-tape an FTL drive to it, and kick it through subspace to a prearranged pickup location.

:smallredface:
Yes. That is what I meant. I actually have that as part of just about every sci-fi setting I put together, I think it works really well to introduce the same feeling as the age of sail, where the captain of a vessel wasn't just in charge of the ship, but was an empowered representative of their government. Being able to call home for orders makes those stories less interesting to me.

Toy Killer
2013-09-23, 05:48 PM
Well, i was planning on having the crew be able to reach the corporate offices, just to be told in a very PR savvy way that it's not Economically viable for the crew to be rescued as the final nail in their hope's coffin that Headquarters will send in the cavalry.

basically S-Mail is a suped up E-mail, able to be used interstitially, but company regulations prohibit it for anything other then emergencies. Maybe it eats up too much 'bandwith' for their future-y FTL communications?

The Grue
2013-09-23, 05:59 PM
Well, i was planning on having the crew be able to reach the corporate offices, just to be told in a very PR savvy way that it's not Economically viable for the crew to be rescued as the final nail in their hope's coffin that Headquarters will send in the cavalry.

basically S-Mail is a suped up E-mail, able to be used interstitially, but company regulations prohibit it for anything other then emergencies. Maybe it eats up too much 'bandwith' for their future-y FTL communications?

Say it uses quantum entanglement. I'll spare you the math, but basically you can only use a given pair of entangled particles to transmit information once, after which it's useless. This means that if you want to transmit one megabyte of information by quantum communicator, you're going to need a container with a minimum of 8,388,608 q-bits whose entangled pairs are already at your destination.

In other words, perfectly feasible, instantaneous (and in a fun way that breaks causality!)but impractical for anything other than infrequent, low-gain traffic. Perfect for an emergency communicator; you'll only ever need to use the Red Phone once per mission.

Toy Killer
2013-09-23, 06:08 PM
Say it uses quantum entanglement. I'll spare you the math, but basically you can only use a given pair of entangled particles to transmit information once, after which it's useless. This means that if you want to transmit one megabyte of information by quantum communicator, you're going to need a container with a minimum of 8,388,608 q-bits whose entangled pairs are already at your destination.

In other words, perfectly feasible, instantaneous (and in a fun way that breaks causality!)but impractical for anything other than infrequent, low-gain traffic. Perfect for an emergency communicator; you'll only ever need to use the Red Phone once per mission.

And in a game of Dread, there is only one mission. It's a pretty simple system that is best used simulating Horror stories. I like space horror a lot, and have a guilty pleasure in watching Pandorum (despite it's abysmal quality...). So I'm having my own go at it, mixing up the plot of Virus and Alien together.

Then I'm going to make the adventure(?) my first true graphic novel. it should be fun.

The Grue
2013-09-23, 06:29 PM
And in a game of Dread, there is only one mission.

When I read that sentence, I imagined it was being said by Jeremy Clarkson. I don't know why.

Sir_Mopalot
2013-09-24, 12:59 AM
My understanding is that that's a common misconception about quantum entanglement, because the qbits can be in any of four Bell states, and to complete the communication, the sender of the information needs to transmit the bell state by a classical method, which (obviously) is slower than light and subject to all the same issues that it would if you were simply sending the message by that classical method of communication. Quantum entanglement communication is most useful because it is essentially "baked in" encryption that no-one can understand without having one of the entangled pairs.

EDIT: The way I had it explained to me is that it's a little bit like taking two playing cards, and giving one of them to a friend without looking at which one he has. Even if my friend then goes to the other side of the universe, if I look at my card, I instantly know what my friend's card says. An example of information moving faster than the speed of light, but not very useful for a FTL communication system.

TuggyNE
2013-09-24, 02:17 AM
EDIT: The way I had it explained to me is that it's a little bit like taking two playing cards, and giving one of them to a friend without looking at which one he has. Even if my friend then goes to the other side of the universe, if I look at my card, I instantly know what my friend's card says. An example of information moving faster than the speed of light, but not very useful for a FTL communication system.

If that was actually the case, it would still be rather useful. But apparently even that analogy is misleading.

Discussion here.

Sir_Mopalot
2013-09-24, 02:55 AM
Heh. Yeah, it appears it's more like "You buy two identical decks of cards. You give one to your friend. He goes across the universe. You both then open your decks of cards, and discover, quelle surprise, that you have a deck of cards." But again. Story is the important thing, everything else can screw off.

The Grue
2013-09-24, 05:32 PM
My understanding is that that's a common misconception about quantum entanglement, because the qbits can be in any of four Bell states, and to complete the communication, the sender of the information needs to transmit the bell state by a classical method, which (obviously) is slower than light and subject to all the same issues that it would if you were simply sending the message by that classical method of communication. Quantum entanglement communication is most useful because it is essentially "baked in" encryption that no-one can understand without having one of the entangled pairs.

EDIT: The way I had it explained to me is that it's a little bit like taking two playing cards, and giving one of them to a friend without looking at which one he has. Even if my friend then goes to the other side of the universe, if I look at my card, I instantly know what my friend's card says. An example of information moving faster than the speed of light, but not very useful for a FTL communication system.

I know it's not exactly how it works, but it's a close approximation I've used in SF settings; you entangle particle pairs at a facility somewhere, and then ship one half of the entangled pair each to the two parties who want to communicate. Easy to do if you've got faster-than-light stardrives.

You could easily devise a hub-like routing system to enable your quantum-communicator to talk to anyone else's communicator; one pair goes with your comm, the other stays at the hub with a pair from every other communicator that's ever been made. You connect to the hub, the hub uses classical means (radio signals, fiber-optic cables, etc) to route incoming, decoded information from the box with your particle pairs to one belonging to your pal on Romulus, who then gets your message. Instantaneous, apart from the signal delay at the hub where information is being transmitted conventionally between each q-modem.

Only limitation is the entangled pairs have to be physically shipped around, and they need to be replaced regularly. Not practical for frequent on-demand communication, no, but if you put one in every starship it makes for a feasable emergency batphone.

Amidus Drexel
2013-09-25, 09:33 PM
Sure they do! You just have to go down the Pants of Space the other way. :smalltongue:

The fastest way to a universe's heart is through its pants. :smallamused:

Mutazoia
2013-09-28, 09:06 PM
WhatI'm not saying that there aren't environments that electronics can't handle but human brains can. I'm saying that there aren't spaceships that can have their electronics out of function but still perform interstellar travel while maintaining life support. Fictitious magic forces or no.

It really depends on your method of (and what you consider to be) life support. Fictitious magic forces? Every play Spell Jammer? No electronics in there what so ever and yet...atmosphere, heat, gravity...in sort...life support.

So one can start by evaluating what we would need for life support that is not magic (or (massively) electronic) dependent: Oxygen to breath, heat to keep from freezing to death, gravity to keep muscles from atrophying over long voyages would be nice, but if we're talking FTL then you don't necessarily need gravity.

1. How to provide Oxygen with out electronics. Simplest of solutions...oxygen tanks. Big and cumbersome, and takes up a lot of the ships mass. Water? The ship has to carry water in any case, and depending on the power source of the vessel you'll probably be using water as a coolant as well as a drinking source for the crew. In a softer sci-fi setting I could see hand waving a filter, much like a fishes gill that removes the oxygen from the water with little to no power required. If you have a nuclear type reactor then your producing energy, electronic's or no. Electrolysis is easy enough, that grade school kids do it for science fairs. Batteries (and solar collectors) work wonders.

2. How to heat your vessel. Depending (again) on your power source your power core would most likely provide plenty of heat. The entire outside of your ship could be a giant heat-sink cooling your reactor with the nice cold minty freshness of space, which would leave the inside of the ship nice and toasty warm. (You would probably be living near the outer hull..the further in toward the core you got, the hotter it would get.) Even with the rest of the electronics shut down a nuclear type reactor will generate heat all on it's own and will still need to be cooled some how. Space...the universe's largest heat sink. (also steam can be used in maneuvering by blasting pressurized steam from control valves along the hull. Not really a life support issue but it's always nice to know you can maneuver with out (some form of electronic) power.)

3. Gravity. Easy one here. A simple spin along the ships axis will produce gravity via centrifugal force, and as it so happens in space, a body in motion will stay in motion until acted upon by and outside force. Once your ship start's spinning you don't really need any power to keep it spinning. You ships would end up looking like cigars and, when gravity is enabled, your deck (floor) would be the outer hull (in the outer most or top deck).


I'll do you one better: there aren't spaceships that can perform interstellar travel.

Sure there are! The Apollo moon lander can make an interstellar voyage. It will take centuries, anybody in it will be long dead (but nicely preserved due to the cold) and it's going to be, quite literally, hit or miss where it ends up. But it can do it.

I think you meant "There aren't spaceships that can perform [faster than light] interstellar travel."

Technically true. Currently. But then again...once upon a time the Sun revolved around the earth, which was quite flat. It was considered insane (and some times quite funny) for a man to attempt to fly. Barely 200 years ago people actually believed that if you traveled faster than 35 miles per hour, demons would take your soul (even though a running horse (an hence the person riding it) can do around 55 mph.)

So we'll have to amend your statement to read "There [currently] aren't spaceships that can perform [faster than light] interstellar travel."

Factually true. But then this post is about a Sci-Fi ship...so hard science (as we currently know it) has to take a back seat for the time being.


Similarly: is there a scientific law or theory that requires computers to do any of the tasks on an interstellar spaceship? Well, there isn't. That, again, makes it an engineering problem. As long as science allows it, all engineering problems need are resources and know how, which are the easiest things to provide in fiction.

Actually there is. The law of "oh my god there is so much data to crunch and so many systems to monitor and minutely adjust that an entire army (literally) of humans would be needed to do the job that a computer can do." Which is why NASA uses extremely complex computers on the ground and in even the most simple of capsules. Unfortunately, the only way to have an interstellar spaceship not require computers at all is to turn it into a giant, hollow bullet, load everybody inside and shoot it at the destination (http://www.mckinley.k12.hi.us/ebooks/pdf/moon10.pdf).


That's like saying that because someone can swim across the English Channel, swimming around the entire world is feasible.

You know...there was this one guy (http://en.wikipedia.org/wiki/Beno%C3%AEt_Lecomte)....


And in a game of Dread, there is only one mission. It's a pretty simple system that is best used simulating Horror stories. I like space horror a lot, and have a guilty pleasure in watching Pandorum (despite it's abysmal quality...). So I'm having my own go at it, mixing up the plot of Virus and Alien together.

Then I'm going to make the adventure(?) my first true graphic novel. it should be fun.

If you like Pandorum...try Event Horizon (http://www.imdb.com/title/tt0119081/)....

Sir_Mopalot
2013-09-29, 01:15 AM
Uh, buddy? As a general rule of etiquette, most of the playground prefers that people do one large post, not 5 posts in a row.

Mutazoia
2013-09-29, 09:13 AM
And if I had known there would be several posts I was going to reply to ahead of time I quite possibly would have done just that....curse my ability to see into the future for failing me just when it would annoy you the most :)

TuggyNE
2013-09-29, 07:17 PM
And if I had known there would be several posts I was going to reply to ahead of time I quite possibly would have done just that....curse my ability to see into the future for failing me just when it would annoy you the most :)

Edit Post is your friend. And ours too.

Mutazoia
2013-09-29, 09:32 PM
Edit Post is your friend. And ours too.

eh...I'll just use word pad as a scratch sheet from now on lol

Geordnet
2013-10-05, 06:58 PM
Interesting how this thread turned out...


Sorry for not being clear, I guess, I didn't know what I wanted to ask for?
Don't worry, I know exactly what that feels like. :smalltongue:



A space elevator would be a game-changer. A civilization is NEVER going to be a space civilization without a space elevator.
Actually, there's another way. The Verne Gun. (http://www.kschroeder.com/weblog/archive/2009/03/04/the-verne-gun)

The best part is, it works with current technology. No, seriously; you should tell everyone you know about it. :smallbiggrin:



Simplest of solutions...oxygen tanks. Big and cumbersome, and takes up a lot of the ships mass.
That's kind of like saying the simplest solution to the problem of currency is to just carry around bars of gold on your back.

Sure, it's technically correct... But it certainly isn't practical.



Water?
Fun fact:

The human body actually produces more H2O than it consumes.

So the problem isn't bringing the H2O, it's filtering everything else out of it. :smallamused:



2. How to heat your vessel.
No need to worry about that, humans are exothermic! :smallbiggrin:

In fact, you're actually going to need to use cooling to keep the crew from roasting alive in their own body heat. There is no good way to do this as only one of the three ways of moving heat works in a vacuum.

Solving this problem is one of the greatest engineering challenges in designing real-life spacecraft.


Depending (again) on your power source your power core would most likely provide plenty of heat.
Not "most likely"; WILL. Unless it can violate the laws of thermodynamics, or has a 99.999% efficiency, (just 90% won't cut it) it will.


The entire outside of your ship could be a giant heat-sink cooling your reactor with the nice cold minty freshness of space, which would leave the inside of the ship nice and toasty warm.
Wouldn't work, unless you consider glowing white-hot to be "nice and toasty warm".

The thing is that space is only cold because of an absence of stuff to conduct heat. Which means for practical purposes, the heat of an object in space stays in that object.



(You would probably be living near the outer hull..
:eek:

Dear god, why would you want to be closer to the deadly cosmic rays?!?


the further in toward the core you got, the hotter it would get.)
...Unless you're implying that the reactor isn't on a 200m stick with a thick shadow shield shield to protect the crew.

:eek:



Space...the universe's largest heat sink.
Also the universe's worst heat sink.

No, really; it's physically impossible to be a better insulator than hard vacuum. :smalltongue:



(also steam can be used in maneuvering by blasting pressurized steam from control valves along the hull. Not really a life support issue but it's always nice to know you can maneuver with out (some form of electronic) power.)
Inefficient. Try Hydrazine instead. :smallwink:



So we'll have to amend your statement to read "There [currently] aren't spaceships that can perform [faster than light] interstellar travel."
*cough*

Science doesn't work that way. We know, from experiment, that relativity is correct. Unlike the farcical examples you gave, we know this because scientists went out and tested it.

So, unless you happen to have more than infinite energy lying around, and an engine which can impart that to an object in exactly zero seconds, and know what the square root of negative one looks like from the inside, then faster than light travel without cheating (like the Alcubierre drive) is impossible.


Factually true. But then this post is about a Sci-Fi ship...so hard science (as we currently know it) has to take a back seat for the time being.
This thread was started for the express purpose of discussing the hard science of a sci-fi ship. :smallannoyed:

Toy Killer
2013-10-05, 09:00 PM
Huh, fancy that.

I never considered the endo/exothermic thing before...

Well, I will presume they have a means that's pretty efficient (Maybe not 100%, but pretty close) but not efficient enough; as in the temperature ramps up the longer the jumps between planets are, making a jump longer then 6 days pretty excruciating to endure.

Adoendithas
2013-10-06, 08:54 AM
About getting rid of excess heat:

Wouldn't it be possible to effectively paint the ship with a pigment that is dark in the far infrared, allowing it to radiate excess heat away? I don't know of any pigment like that, but it would be possible to find one through trial and error.

Mastikator
2013-10-06, 04:18 PM
It really depends on your method of (and what you consider to be) life support. Fictitious magic forces? Every play Spell Jammer? No electronics in there what so ever and yet...atmosphere, heat, gravity...in sort...life support.

So one can start by evaluating what we would need for life support that is not magic (or (massively) electronic) dependent: Oxygen to breath, heat to keep from freezing to death, gravity to keep muscles from atrophying over long voyages would be nice, but if we're talking FTL then you don't necessarily need gravity.

1. How to provide Oxygen with out electronics. [snip]

2. How to heat your vessel. [snip]
3. Gravity. Easy one here.[snip]
All of that is well and good except two things. Spell Jammer isn't sci-fi, it's fantasy. What's the point of brining aerospace engineers into this discussion if this isn't hard sci-fi?
The second thing is interstellar travel. You can't rely on oxygen tanks if it's a STL generational ship, a generational ship needs to be able to sustain itself indefinitely (or at least the centuries it would take to reach the destination). So it has to be a FTL ship. How do you propose to go faster than light without involving electricity in a as-hard-as-possible sci-fi scenario?

Rakaydos
2013-10-06, 04:27 PM
Step through a wormhole? (stargate, any setting with jump points)
Catch interdimentional tachion radiation on specially tuned sails, generate an imbalance, and use the pressure to shift to other dimentions. (With the Lightnings, by David Drake)

EDIT: also, for STL, a Buzzard Ramjet with hydroponics bays collecting radiation from the fusion torch.

Mastikator
2013-10-06, 05:51 PM
Tachyons is soft sci-fi though.

Wormholes might work, but it does beg the question of why bothering of going into space if you can worm-hole you way to anywhere. Space is hostile and uninteresting, why not just worm-hole to the destination from the ground?

Rakaydos
2013-10-06, 06:10 PM
Tachyons is soft sci-fi though.

Wormholes might work, but it does beg the question of why bothering of going into space if you can worm-hole you way to anywhere. Space is hostile and uninteresting, why not just worm-hole to the destination from the ground?

Humans around other stars is soft scifi, however you do it. The entire "cant use electricity" question is based around a common soft-science conceit- humans need to go to the stars themselves, and cant just send their AI children to conquer the galaxy by proxy. Ergo, AI must not work, for one reason or another.

Youre right, why bother use space if you have wormholes? I'm pretty sure there's a show about that... :P

Adoendithas
2013-10-06, 06:31 PM
Humans around other stars is soft scifi, however you do it. The entire "cant use electricity" question is based around a common soft-science conceit- humans need to go to the stars themselves, and cant just send their AI children to conquer the galaxy by proxy. Ergo, AI must not work, for one reason or another.

Youre right, why bother use space if you have wormholes? I'm pretty sure there's a show about that... :P

Wouldn't wormholes near planets cause massive problems (pun intended)?

Rakaydos
2013-10-06, 06:40 PM
Wouldn't wormholes near planets cause massive problems (pun intended)?

Depends on how hard you're being, I suppose.

Geordnet
2013-10-06, 08:06 PM
About getting rid of excess heat:

Wouldn't it be possible to effectively paint the ship with a pigment that is dark in the far infrared, allowing it to radiate excess heat away? I don't know of any pigment like that, but it would be possible to find one through trial and error.
That's basically what they actually do: they have panels of radiators which release heat through blackbody radiation.

Although, there are a few reasons why they still can't just use the body of the spacecraft itself for the job, at least not with large spacecraft:

The radiators themselves have to be hot enough to roast humans alive in order to reject heat at any reasonable rate.
Blackbodies absorb heat as well as reject it, and there's 24 hours of sunlight in (interplanetary) space. Which is why NASA generally paints its ships white.
The biggest source of heat (the reactor) absolutely MUST separated from the crew compartment by a very long pole. (Unless said crew is suicidal.) So there's no reason to move the heat to the body of the ship, instead of radiating it right there. (Where it's easier, anyways.)




Tachyons is soft sci-fi though.

Wormholes might work, but it does beg the question of why bothering of going into space if you can worm-hole you way to anywhere. Space is hostile and uninteresting, why not just worm-hole to the destination from the ground?
Easy enough: make the size limit on wormholes microscopic. :smalltongue:

(Oops, wait; I thought we were talking about wormhole-based communication.)

Adoendithas
2013-10-06, 09:25 PM
That's basically what they actually do: they have panels of radiators which release heat through blackbody radiation.

Although, there are a few reasons why they still can't just use the body of the spacecraft itself for the job, at least not with large spacecraft:

The radiators themselves have to be hot enough to roast humans alive in order to reject heat at any reasonable rate.
Blackbodies absorb heat as well as reject it, and there's 24 hours of sunlight in (interplanetary) space. Which is why NASA generally paints its ships white.
...snip...

That makes sense, otherwise you could make heat flow from a colder area to a warmer one and break thermodynamics. But materials can be made that reflect only certain frequencies of radiation. Couldn't you have a pigment that radiates and absorbs really well in a certain part of the far infrared, but reflects all visible light? The light from the Sun is concentrated in the visible range, so it would be reflected, but the heat of the ship itself could be radiated away into space.

I don't know if such a material exists, but it doesn't seem to break any physical laws. I imagine we just haven't found one because it's so much easier to tell if something makes a good pigment when you can directly see its "color."

Geordnet
2013-10-06, 11:05 PM
The light from the Sun is concentrated in the visible range,
This is where the problem is. The light from the sun after being filtered through Earth's atmosphere is concentrated in the visible range, but the full spectrum is much closer to true blackbody radiation.

http://upload.wikimedia.org/wikipedia/commons/4/4c/Solar_Spectrum.png


And as it turns out, what you're looking for already exists: several normal, everyday white paints work this way. The real problem is the first one I listed: the radiators need to be really, really HOT in order to work fast enough to cool the reactor.

(For just the crew, it turns out the body of the spacecraft can actually work. It did for the Apollo Program, at least; a larger ship might need more due to the square-cube law and all that.)


Yeah, space is weird. It's simultaneously colder than the coldest tundra yet hotter than the hottest desert. :smalltongue:

Mando Knight
2013-10-06, 11:37 PM
Yeah, space is weird. It's simultaneously colder than the coldest tundra yet hotter than the hottest desert. :smalltongue:

Because

While the average energy per volume of space is pretty low, the energy of the little bits of stuff that's there is actually a lot higher.
Vacuum is a goddamn insulator! It's how your Thermos works, except eleventy zillion times bigger!
#1 and #2 are because vacuum doesn't have a temperature! It's nothing! It's a close-as-infinite-as-the-universe-gets expanse of nothing, with clumps of something here and there. Heat transfer and temperature as we intuitively know it only makes sense when there's something.

The Grue
2013-10-07, 12:59 AM
Humans around other stars is soft scifi, however you do it.

Alistair Reynolds would like a word with you.

Rakaydos
2013-10-07, 01:17 AM
Alistair Reynolds would like a word with you.

And what exactly is fueling these massive generation ships, both getting them beyond solar escape velocity, and correcting for galactic wind over centuries of travel? Even the Orion Drive will run out of explosives, and for everything else there's massive fuel-to-mass efficency problems.

Tehnar
2013-10-07, 02:29 AM
And what exactly is fueling these massive generation ships, both getting them beyond solar escape velocity, and correcting for galactic wind over centuries of travel? Even the Orion Drive will run out of explosives, and for everything else there's massive fuel-to-mass efficency problems.

Doesn't Reynolds use Bussard ramjets in his novels (Revelation space, Redemption Ark). Those can theoretically work (at least outside of the local bubble) so its fairly plausible.

Delta
2013-10-07, 05:57 AM
Doesn't Reynolds use Bussard ramjets in his novels (Revelation space, Redemption Ark). Those can theoretically work (at least outside of the local bubble) so its fairly plausible.

I don't remember that Reyonlds ever explicitly states what kind of drive the (old) lighthuggers actually use, he only goes into more details later when the technology tends to turn Weird

Adoendithas
2013-10-07, 07:31 AM
This is where the problem is. The light from the sun after being filtered through Earth's atmosphere is concentrated in the visible range, but the full spectrum is much closer to true blackbody radiation.

http://upload.wikimedia.org/wikipedia/commons/4/4c/Solar_Spectrum.png


And as it turns out, what you're looking for already exists: several normal, everyday white paints work this way. The real problem is the first one I listed: the radiators need to be really, really HOT in order to work fast enough to cool the reactor.

(For just the crew, it turns out the body of the spacecraft can actually work. It did for the Apollo Program, at least; a larger ship might need more due to the square-cube law and all that.)


Yeah, space is weird. It's simultaneously colder than the coldest tundra yet hotter than the hottest desert. :smalltongue:

Aha, I see now. I'd forgotten about the atmosphere.


Doesn't Reynolds use Bussard ramjets in his novels (Revelation space, Redemption Ark). Those can theoretically work (at least outside of the local bubble) so its fairly plausible.

Wasn't the amount of interstellar hydrogen discovered to be way less than Bussard had assumed?

Rakaydos
2013-10-07, 09:42 AM
Wasn't the amount of interstellar hydrogen discovered to be way less than Bussard had assumed?

I recall a discussion relating to Niven that claimed that, given the efficency of nuclear fusion, a buzzard ramjet would hit terminal velocity (where acceleration from the rocket would be canceled by drag from the scoop) at around 1/5 of lightspeed- not even high enough for good relativistic effects.

Tehnar
2013-10-07, 11:12 AM
It is lower in the local bubble, some 300 ly around earth. Outside that it should be as Bussard calculated.

The bigger problem is that pp fusion gives some 0.2c velocity exhaust so you get a lot of diminishing returns on increasing your speed after that.

Still 0.2c is ppretty solid if you have coldsleep tech.