interesting, but certain things were innaccurate.

Mostly the "spacefighter" parts. A 1-2 man space "fighter" in the way an F-14/-15/-16/-18 is a "fighter" are useless in space because all spacecraft work in the same environment (the only difference is if a spaceship can enter and exit atmosphere; that is, land/ascend on/from a planet).

Effectively, what we consider "fighters" are never going to be in space. Not when a missile will do the job for a much cheaper cost because- a missile bus (re: missile that shoots missiles) is cheaper than a manned "fighter" (re: 1-2 vehicle that shoots missiles). Both do the same thing, but both have far different capabilities. A disposable missile bus (inherently it would be disposable) will only need enough delta-v (change in velocity, in other words propellant+fuel*) to get to the target, shoot its missile payload, and likely attempt to impact the target.

In contrast, a manned fighter needs 4 TIMES the delta-v a missile bus needs. Why? A missile bus just needs to get to the target, deploy payload, and maybe try to impact the target. A fighter needs to be recovered. But why 4 TIME as much? Simple- you need the delta-v to 1) get there, 2) cancel your inbound vector (assumes "deep space" or interplanetary combat), 3) some extra delta-v for maneuvering in combat, and 4) some delta-v to get to a rendezvous point with the "carrier".

And all that is without the accounting the extra mass of life support systems and similar.

*Fuel and Propellant are only rarely the same. Fuel is what is used by a propulsion device to create energy, Propellant is what actually works the magic of Newton's Law of Action&Reaction. Pretty much only chemical rockets (like firecrackers, backyard rocket kits, the Space Shuttle, Saturn V) have a fuel/propellant that is the same. Think of it this way- in an ion or plasma thruster (you know, the one that uses a lot of electricity and glows a pretty blue color) uses an electrical power source (like a nuclear reactor or maybe solar panels) for "fuel" (the power source generates the needed energy), and a typically gaseous propellant like Xenon (ion drives) or Argon (plasma drives).

Nuclear propulsion is very similar except- in fission based systems, Uranium, Thorium, or Plutonium can be used for fuel (energy-creation for the drive), while water or hydrogen are the preferred propellants. Fusion propulsion uses either deuterium/tritium, deuterium/deuterium, or helium, boron, or other low-mass atoms that combine very easily (in various combinations) to create energy. Fusion and Fission based propulsion systems use very similar propellants.

well, I can find a rationale for a fighter.

A ship that is air/space. Basically, a "fighter" launched from space that can then enter atmosphere and strike ground targets (this is a psychological effect thing, and it may be more economical to preserve ship munitions for ship-to-ship/-station engagements), and then ascend back into space.

That, or the "Fast Attack Craft", used to investigate possible resources and defend them from light assaults. FACs could also be useful for striking small or weak orbital targets (like communications satellites) while the big ships take out the "starbases" and orbiting defender's ships.

EDIT: also, Jonnan- nice avatar. Very funny. 2 thumbs up man!

Right. So when the evil alien Conquerers from the next galaxy over feel the need to expand because they were agressive enough to take out the goody-goody There's-no-war-in-space-because-we-can-nuke-them-back-to-the-stone-age races before they could nuke the hostile homeworld, we should just roll over to them because in the thousands of years since any species has had any combat experience we've all grown soft and squishy.

Also if a galactic nation has the ability to wage war on another, would that not require many worlds in many systems producing the raw materials needed to fund the military? Wouldn't destroying their homeworld only push them to fight longer and harder? And if they were planning to go to war with another nation, would they reveal sensitive information like comm-channels and the location of major construction, political, and economic planets and systems? Even if you had been at peace with them, and suddenly decided to invade for reasons unknown, why would you give away the position of any critical outpost or comm frequency?

But that could just be my imagination running wild.

that was a good read! thanks.

I have no problem with anything you have said except for this. The TLAM is land attack only and is completely unable to take control of an AO (area of operations, don't mean to be snobby if you do know what it means, just a lot of ppl I know don't). The F-18 on the other hand can engage air and ground targets alike, and unlike most conventional warhead TLAMs can engage multiple targets. Also the F-18 can be re-equipped depending on the mission with things like surveillance equipment or electronic warfare equipment. Also TLAMS are more conventionally fired from ships other than carriers, whereas the F-18 helps make our carriers some of the most lethal ships on the planet.

A better example might have been the F-117 or the B-2. However, ironically enough the B-2 can carry and fire cruise missles similar to the TLAM so that one isn't quite as good an example either. Also both of those can attack more than one target unlike the conventional warhead TLAM.

Other than that example, it would appear that you would be correct. However depending on the type of weaponry/propulsion/technology deployed if/when we do start fighting wars in space, the viability of space fighters could change.

@lifekatana- Both spheres and cylinders (or cigar-shaped) ships have pros&cons.

Cylinders/cigar-shape can sustain much higher acceleration* and mass loads than a sphere, but cannot turn as fast.

Spheres can pretty much be swept around in a jiffy, but must have a very precisely balanced internal cargo while under acceleration, and cannot support the higher acceleration and mass loads of a cylinder.

*by high acceleration, I mean the rate at which something can gain velocity. Not the maximum velocity attainable (which is dependent on the duration of acceleration or the max exhaust velocity of a propulsion system (since it's impossible to go faster than your exhaust).

@Dragoon4ever- the basic principle of a "TLAM" outperforming an "F-18" in space still applies. In atmospheric operations the points you bring up matter quite a bit, but in space, a "TLAM" can be fitted with different warheads (modular warhead packages could even be fitted before weapon deployment if necessary); additionally it is nigh impossible to take control of an AO (I actually didn't know what the term was, nor had even heard of it, before today; thanks because it will actually be quite useful for me) in space (the closest to having control of an AO is area denial; that is, you have enough reach that a substantial area is denied the enemy because it is too risky to attempt to operate in a certain area).

In space, surveillance/reconnaissance will be done by a ship, and not a fighter, because- the ship can carry bigger sensors, and space is EXTREMELY sensor friendly.

I refer you to the good site http://projectrho.com/. You will have to navigate from their to the section "Advanced Design". For assistance on why a cigar (which is actually a cylinder, so I made a mistake their a little) is better (or worse, you decide). Note on the acceleration bit- a "cigar" and a sphere will both be capable of the same final velocity (assuming they have the delta-v and comparably powerful propulsion systems). The rate at which they gain the velocity will be different.

HERE's some on why a cylinder is good/bad-

The cylinder is more aerodynamic (for take-off and landing on planets with atmospheres), and allows the use of a smaller anti-radiation shadow shield (because from the point of view of the reactor the body of the ship subtends a smaller angle). It also lends itself well to the tumbling pigeon concept since it does not have to spin as fast as a sphere of the same volume in order to generate the same centrifugal gravity.

Drawbacks include a larger surface area, and a larger "moment of inertia" for yaw and pitch maneuvers (but a lower moment of inertia for roll maneuvers). This means it takes forever to point the ship's nose in different directions as compared to a sphere, which means poor maneuverability (See short story "Hide and Seek" by Sir Arthur C. Clarke for details). Larger gyros or stronger attitude jets will be needed. A faster roll rate is actually not of much use, unless you are trying to get a weapon turret to bear on an enemy ship (See the wargame Attack Vector: Tactical for details).

Cylinder shapes are also better if your ship has a so-called "spinal mount" weapon, that is, where instead of mounting a weapon on your ship you instead build the ship around the weapon. Such weapons are typically long and skinny, which fits the profile of a cigar more than a sphere

AND now the sphere-

Spheres have the largest enclosed volume for the smallest surface area of any shape, which is a major advantage where every gram of structural mass is a penalty. They also have a smaller moment of inertia for yaw and pitch maneuvers. Drawbacks are the opposite of the cylinder: they are only slightly more aerodynamic than a brick, they don't shadow shield well, and they are lousy tumbling pigeons.

Spheres also require more internal support structure than cylinder to handle the same acceleration load, particularly if you're going to be putting decks inside of it that rely on the structural framework of the spheroidal hull for rigidity. Cylinders under acceleration support themselves in the same manner as a skyscraper building, spheres need extra bracing to keep the equator from sagging. Of course this only becomes a problem if the acceleration is greater than a tenth of a gee, neither spheres nor cylinders have any problem coping with milligee acceleration.

On the other tentacle, if the shape has to be pressurized, like a fuel tank or a crew compartment, non-spherical shapes require more bracing mass and are more expensive to construct than spherical shapes.

Ken Burnside noted that another drawback of a sphere is that your internal volume is going to have a lot of "wasted dead spaces" near the hull. Odd shaped volumes that are what happens when you have an interior wall sectioning off part of the curved surface of the sphere. Anybody who has tried to lay out a floor plan inside a Buckminster Fuller geodetic dome house knows the problem.

AND a bit of comparison-

Yet another thing to keep in mind is that using current manufacturing techniques, constructing a cylindrical hull costs about 70% of the cost of constructing a spherical hull with the same volume.

Why? Because it is more difficult to manufactured girders and plates that are bent compared to straight ones. A cylinder is constructed using straight stringers. The frames are circular, but all the frames have the same radius and radius of curvature. A sphere on the other hand uses curved stringers and circular frames all of different sizes (well, there are actually two frames of each given radius, but you understand the point I'm trying to make).

On most modern wet-navy warships, the hull plates are mostly straight, with a few bent in one dimension, and only a couple bent spherically in two dimensions. Bending is expensive. Eliminating the bending cost will require one and perhaps two breakthroughs in manufacturing technology.

SO there you have it. (capitalized 1st words are for differentiation of sections). EDIT: Forgot to mention this- the shapes are reduced to the fundamentals. As for the exhaust velocity- I read it somewhere and cannot seem to find the source. I am reasonably confident that it is on the Atomic Rockets site.

That, and a "cylinder" shape is also more aesthetically (sp?) pleasing (at least to me).

eww, borg. And ST in general, considering how {pilot: "Captain, we're overteching the tech" Data: "Captain, if we tech this other tech this way it will make the tech being extremely efficient"} and detrimental to perception of science.

and what is to say that the missile/bus must have any interaction with the launching craft whatsoever post-launch? To me, the weapon is equipped with a simple sensor+guidance suite, complex enough to not be fooled by simple countermeasures and simple enough to be cheaply manufacturable.

Effectively, a launch procedure is such that- you detect what you think is the enemy; it is then identified as the enemy. You program the weapon to search the general (w/in a couple 1000 km) area as it flies in to destroy the target. This is for erratic movement compensation on the part of the enemy, as it would be more intelligent to launch the weapon on an intercept trajectory, rather than launch it where you got a contact (which, if distance is on the order of light-seconds (many 100k km), then you see the target where it was, and launch the weapon toward where it will be).

I really think you should check the site projectrho.com. It has some very good arguments for/against fighters (more against than for BTW). I think that fighters make sense in certain, very particular contexts.

Probably the biggest problem about the feasability of spacefighters in general is "what is a space fighter?" Is it an F-15 IN SPACE! or is it a B-1B/B-2/B-52H equivalent craft that is designed to destroy other B-1B/B-2/B-52H equivalent craft?

To me, a traditional "spacefighter" is a 'simple' 1-2 man craft. Therefore, it is probably going to be too small to carry a meaningful amount of ordnance&delta-v. Thus, it can't really do any damage and it can't really get anywhere. One thing to note is that a current F-15 (I believe it's the F-15) weighs about 36 metric tonnes (36,000 kg) fully loaded, sitting on the ground ready for launch. A Boeing 787 weighs between 200-300 metric tonnes. I envision not a spacefighter per se, but a "Fast Attack Craft", a small, 3-5 man crew (dependent on ship size, sophistication, and mission; a combat FAC would likely have 5+, while an exploration/scout FAC might need only 3-5 crewmembers) operating it; the ship itself would weigh in from 200-500 metric tonnes or maybe more.

Thus, in order to really discuss (civilly, as if we wish to devolve into a simple and single-minded flame war, we can just say "missile busez pwn fighterz" and "no, fighterz own missile busez", etc. etc. ad nauseum) spacefighters, we must 1st define what a spacefighter is. I consider it to be a low mass (under 100 metric tonnes) craft, making it rather unfeasible (particularly with current engine technology) to say the least.

If the guidance+sensor suite is simple enough to be cheaply available, eventually countermeasures will show up that are too complicated for it, driving the price up as more and more sophisticated sensors will be needed to counter the countermeasures. I guess I see Missile combat in space as more of a remote guidance sort of thing, while you see it as the instalation of rudimentry AI subsystems onboard the missile. I can see where you are coming from and I accept it as a valid viewpoint, but I guess that you and I will just have to agree to disagree on the viability of a small manned craft in space combat.

Lasers I think they will actually be used. Sure they take energy, but we got fusion in the future!