Stutterwarp and Beyond

[aramis]

Originally posted by Tom Kalbfus:
I still think the star data could stand to be reorganized into sectors and subsectors 50 light year and 25 light year cubes respectively. There are 8 pages of star data to sort through, and they are not arranged by proximity, but in alphabetic order, which means there could be 2 stars 3 light years apart, one begins with A and the other begins with Z.

organizing it suchly would not make it any the easier to use for me; I don't use the NSL until I know the name of the system being searched for from the map(s); having to remember a sector as well (especially since 2300 astrography doesn't lend itself well to arbitrary structures based upon the reference axes) would be more of a pain for me. The 2300 materials (the map) already shows ALL the elligible routes under the givens of the rules, setting and the NSL version used. Which, BTW, intentionally left out some known but not confirmed (as of then) data.

2300's setting uses some small fraction of the systems in the NSL sphere... the rest are "Unreachable" without GM tweaking. (OK, the know 12LY hop for a towed vessel could be done, but if I'm going to do that, I'll just run a quick program to find it.

Hmm. The NSL hop finder could be done as a palm app (using the D^2 >= d(X)^2 + d^2 + d(z)^2 method). I'm not conversant enough with math Lib to do the floating point maths needed on a palm. Nor with database functions on the palm.

if I get REALLY motivated, I might try it.

 

[TKalbfus]

You could also have multiple stutter warp drives on you ship and eject them as they get too hot. Or you can shut them down so it doesn't get any hotter and use your other stutter warp drive and discharge them both when you reach a gravity well, but that's cheating, isn't it?

 

[Colin]

Originally posted by Tom Kalbfus:
You could also have multiple stutter warp drives on you ship and eject them as they get too hot. Or you can shut them down so it doesn't get any hotter and use your other stutter warp drive and discharge them both when you reach a gravity well, but that's cheating, isn't it?

You can eject a drive, then bring another one online. That's exactly what the _Bayern_ did in her flight to the Pleiades. You can't, however, simply take a charged drive off-line and keep it aboard the ship. Taking a charged drive off-line can have disasterous consequences, akin to the drive overloading in the first place. Leaving it on-line and using another drive has a similar result, as the first drive continues to build a charge. And no, I'm not making this up.

 

[Colin]

As far as the NSL goes, as far as I'm concerned, the stock list from the original game should be used. Too much of the original material rides on that list and its assumptions. At the same time, I'm not adverse to the idea of, say, a Traveller's Aid for 2300 that has an updated list, along with some alternate setting information. Space and time permitted, maybe something like that could be in the new book, but I think the T2320 setting information has to take priority.

 

[aramis]

Originally posted by Tom Kalbfus:
You could also have multiple stutter warp drives on you ship and eject them as they get too hot. Or you can shut them down so it doesn't get any hotter and use your other stutter warp drive and discharge them both when you reach a gravity well, but that's cheating, isn't it?

Actually, that is covered in the rules, and is a no go. you can't safely shut down a charged drive. you CAN tow a totally inactive drive, and eject or otherwise dispose of the charged one, but until discharged, it continues to gain charge, and WILL blow up sooner or later.

the rules provide for the "Two Ship" solution (one way) or "Three Ship Solution" (Two way). In either case, since deep space meetings are hard to do, and "Hot drives can't be shut down", it assumes that the 3SS is actually a two way set of the 2SS.

the 2 ship solution works this way: ship A tows ship B to 3.5 LY out. Ship B then brings on-liine it's drives, and goes to system 2, up to 7.7 LY out from there. 11.2 LY. Ship A then returns to the port of origin.

on the three ship solution, A tows B one way, and C tows B the other way, establishing a two-way (and expensive) link.

In theory, one could add a third stage, and get 15.5 LY or so... but the cost is probably prohibitive.

 

[TKalbfus]

Also doesn't a stutterwarp drive make the starship harder to hit? The ship after all has a pseudo-velocity, momentum doesn't apply. The ship can suddenly make right turns and whatnot. If you are going to target a ship using its stutterwarp, your going to have to anticipate where the ship is going to be when the missile/projectile/laser beam is going to arrive. With a normal velocity, the ship has to accelerate to reach a certain speed, its future position is somewhat more predictable. Now what if you set the stutterwarp to blink in a random direction? i.e., the ship jumps, forward, backward, up , down, left, right, many times per second. Instead of having an illusionary speed, it has a probability function on its position. The ship looks blurred and out of focus and covering an area that's larger than its volume. If the ship can blink its length the probability of it being in any one position would be 3.7% or 1/27. This is at a cost of the ship's ability to maneuver. What do you think, can a stutterwarp be used this way?

 

[aramis]

Originally posted by Tom Kalbfus:
Also doesn't a stutterwarp drive make the starship harder to hit? The ship after all has a pseudo-velocity, momentum doesn't apply. The ship can suddenly make right turns and whatnot. . This is at a cost of the ship's ability to maneuver. What do you think, can a stutterwarp be used this way?

follow the logic trail here;
1) we can target hem effectively with lasers, therefore the firing solutions must exist.

2) drive speed doesn't significantly affect firing solutions per the rules, therefore the increased maneuverability is a minor issue.

3) turn modes exist, therefore the ship can't "Suddenly" do a right angle turn, and therefore has pseudo-inertia of some kind.

4) That higher efficiency drives recieve no bonuses for high pseudo-velocity in terms of damage taken, the tunnelling efffect is not marco-distance enough (per displacement pulse) to warrant mechanical inclusion

5) that the displacement is short enough in duration to be longer than the beam pulse.

This leads to traditional hang-time-fire fire solutions for space combats: either you are close enough for "He can't be out of the way before my shot arrives" (much like modern short range artillery, especially missile artillery), or "Where could he end up being, saturate that zone". the latter relies upon high volume of fire for minimal hits, but can guaratee hits if sufficient fire is available, ala WW II through 'nam era massed artillery battery fires... you know your target was at X location, and can only move Y speed, so at (Time of Fire + Flight time) it will have to be within this "circle", so we put overlapping rounds so that the entire area described is beaten.

the only real concessions made by GDW in the design are that missiles use stutterwarp, too, and thus could be out-run in theory, and can be shot before they fire.

 

[TKalbfus]

follow the logic trail here;
1) we can target hem effectively with lasers, therefore the firing solutions must exist.

2) drive speed doesn't significantly affect firing solutions per the rules, therefore the increased maneuverability is a minor issue.

3) turn modes exist, therefore the ship can't "Suddenly" do a right angle turn, and therefore has pseudo-inertia of some kind.

4) That higher efficiency drives recieve no bonuses for high pseudo-velocity in terms of damage taken, the tunnelling efffect is not marco-distance enough (per displacement pulse) to warrant mechanical inclusion

5) that the displacement is short enough in duration to be longer than the beam pulse.

The velocity of light is 299792458 m/sec. The rules state: At a threshold of 0.0001 Gs Maximum speed for stutterwarp drops below light speed. This is at a distance of 100 Earth Radii from Earth or about 637,800 km from Earth. At this distance, it the Stutterwarp cycles 1 per second, it must displace 299,792,458 meters. Lets assume the ship is cube shaped and is 10 meters on a side. For it to displace its own length, it would have to cycle 29,979,245.8 times per second. The rules would then assume that the ship can only travel in one direction, the direction the starship is pointed in. The warp efficiency number of a starship is how many light years a ship can travel in a day. That means that the ship would steadyly increase it speed as it pulled away from Earth intil it reached that number. 1 light year a day is 365 times the speed of light. Now if the Starship left 6 hours ago, it should have traveled 1/4 of a light year at warp efficiency 1. Now suppose they are bank robbers and the Interstellar Police are after them, 6 hours have past, but the Police can still detect the starship leaving the Solar System, even though it is 1/4 of a light year away. You see the light from the escaping starship as it crossed the orbit of Pluto is only now reaching the vicintity of Earth. The cops can then follow the light trail in pursuit of the robbers. Now lets say the Police Starship has a warp efficiency of 2. In about 12 hours the police starship catches up to the robbers and pulls alongside them, they are in interstellar space, with no gravity wells nearby and traveling at 365 times the speed of light. Now one police sergent gets the bright idea of knocking out the robbers stutterwarp drive so the can be captured, so he carefully aims the laser cannon at the robber ship and fires. What do you think happens? He misses, because the other starship is not there by the time the laser arrives, it is traveling at an FTL pseudo-velocity, so how are the Police to capture the bad guys?

 

[Whipsnade]

"The rules state: At a threshold of 0.0001 Gs Maximum speed for stutterwarp drops below light speed. This is at a distance of 100 Earth Radii from Earth or about 637,800 km from Earth."


Mr. Kalbfus,

Yup, the rules most certainly say that. You can't go FTL until you clear the 0.0001 gee limit and Earth's 0.0001 gee limit is roughly 100 times its radius.

Of course, you managed to forget one small thing...

THE SUN

... it has a 0.0001 gee limit too. That is roughly 2.45 AUs or about 1.45 AUs beyond Earth's orbit. Your robbers aren't going to go FTL until they clear that limit.

"Now one police sergent gets the bright idea of knocking out the robbers stutterwarp drive so the can be captured, so he carefully aims the laser cannon at the robber ship and fires. What do you think happens? He misses, because the other starship is not there by the time the laser arrives, it is traveling at an FTL pseudo-velocity, so how are the Police to capture the bad guys?"

Both 2300AD and Star Cruiser explicitly state that FTL ship combat is impossible. Ships only fight inside the 0.0001 gee limit. Beyond that they can't target their weapons and can barely use their sensors, just as you surmised.

How will the cops catch the robbers? They can either hope to catch them before reaching Sol's 0.0001 limit or they can try and trail them to the next star down the arm and effect a capture there. Trailing is tough, so sometimes the robbers get away.

The 3D nature of 2300AD space movement and the 7.7 ly limit tend to restrict which stars a vessel can travel to from any given star. If a vessel leaves one star along a certain vector and maintains that vector long enough, it can only be heading for a certain star or stars. I believe your copy of 2300AD may contain references to 'doglegs', a manuever by which a departing vessel tries to fool an observer into thinking it is heading for one star when it is really travelling to another.

In summary, ships in 2300AD worry more about clearing stellar 0.0001 gee limits and FTL combat in 2300AD is impossible.


Sincerely,
Larsen

 

[aramis]

As for "Capturing the Bad Guys" from Tom's post, the cops (who have a faster drive, if they are meeting in deep space) ares simply going to parralell until they get into the new gravity well... wherein both ships are STUCK in system in most cases, due to drive limits. Then they attempt to effect capture by normal means.

And as for the cyclic rate? 30 MHz seems a little SLOW to me; I've always envisioned 30 GHz to 30 THz displacements; the FTL kicker is the point where the drive can reliablly go from 1-20cm displacements to 10m displacements.


The rules are non-specific as to displacement size, but since at the "Combat Speeds", we know that in the time it takes to fire, the ship is essentially not moving terilby far out of its own way.

(Now, annything with a turn mode describes a funnel shape, at least util the 90degree turn... that funnel, plus accelleration/deceeleration limits, determines just whee you need to put shots. So long as the section of cone based upon time-to target lag that you need to cover is less than the size of the targget, you can get an "aimed hit" rather than a "saturation hit." To assure hits in larger cone sections, you need a number of shots (minimum) equal to the apparent-cross-section-area of the cone section divided by the apparent-cross-section-area of the target, asusuming simmultaneous shots. The math gets UGLY, even though it is very simple conceptually. With true 3D flexibility, it can get really bad.)

 

[TKalbfus]

There should be an inverse square law that determines how fast a stutterwarp goes up to its maximum warp efficiency, based on distance from a given mass. Has anyone worked this out. I can probably write a formula if I have the time, but perhaps its in the rules somewhere. I know that at 1/10,000-G a stutterwarp is traveling at the speed of light. As it approaches the mass, it should slow down according to the inverse square law of gravity, and as it pulls away, it should increase its speed. Couldn't a stutterwarp missile detonate on top of an FTL ship, if it pulls ahead of it first? Also another point. The FTL robbers couldn't see the cops pursuing them until they pulled alongside, since the light from the cops would never reach the robbers. The rule would be whoever's ahead can never see the persuers behind. The persuers can see the persued. Radio communication between two FTL ships is somewhat problematic Perhaps two ships could synchronize their flickering and then could exchange radio voice and video communications.

 

[Colin]

The cut-off points are exactly that, cut-off points. There is no leading up to it. After the 0.001 G threshold. FTL travel is possible. Before it, it isn't and speeds are cut drastically. There is anotehr cut-off, at 0.01 G, I think, after which a stutterwarp can barely provide station-keeping ability.
These are all sudden cuts in performance, without any sort of gradual fall-off. This was, I suspect, mostly to keep it easy, but one could explain as some sort of quantum interaction. <waves hands frantically>

 

[BMonnery]

Originally posted by Tom Kalbfus:
</font><blockquote>quote:</font><hr /> follow the logic trail here;
1) we can target hem effectively with lasers, therefore the firing solutions must exist.

2) drive speed doesn't significantly affect firing solutions per the rules, therefore the increased maneuverability is a minor issue.

3) turn modes exist, therefore the ship can't "Suddenly" do a right angle turn, and therefore has pseudo-inertia of some kind.

4) That higher efficiency drives recieve no bonuses for high pseudo-velocity in terms of damage taken, the tunnelling efffect is not marco-distance enough (per displacement pulse) to warrant mechanical inclusion

5) that the displacement is short enough in duration to be longer than the beam pulse.

The velocity of light is 299792458 m/sec. The rules state: At a threshold of 0.0001 Gs Maximum speed for stutterwarp drops below light speed. This is at a distance of 100 Earth Radii from Earth or about 637,800 km from Earth. At this distance, it the Stutterwarp cycles 1 per second, it must displace 299,792,458 meters. Lets assume the ship is cube shaped and is 10 meters on a side. For it to displace its own length, it would have to cycle 29,979,245.8 times per second. The rules would then assume that the ship can only travel in one direction, the direction the starship is pointed in. The warp efficiency number of a starship is how many light years a ship can travel in a day. That means that the ship would steadyly increase it speed as it pulled away from Earth intil it reached that number. 1 light year a day is 365 times the speed of light. Now if the Starship left 6 hours ago, it should have traveled 1/4 of a light year at warp efficiency 1. Now suppose they are bank robbers and the Interstellar Police are after them, 6 hours have past, but the Police can still detect the starship leaving the Solar System, even though it is 1/4 of a light year away. You see the light from the escaping starship as it crossed the orbit of Pluto is only now reaching the vicintity of Earth. The cops can then follow the light trail in pursuit of the robbers. Now lets say the Police Starship has a warp efficiency of 2. In about 12 hours the police starship catches up to the robbers and pulls alongside them, they are in interstellar space, with no gravity wells nearby and traveling at 365 times the speed of light. Now one police sergent gets the bright idea of knocking out the robbers stutterwarp drive so the can be captured, so he carefully aims the laser cannon at the robber ship and fires. What do you think happens? He misses, because the other starship is not there by the time the laser arrives, it is traveling at an FTL pseudo-velocity, so how are the Police to capture the bad guys? </font>[/QUOTE]They don't. Once you cross the FTL threshold you're going so quickly that you can't even see other ships. The perps don't have to align their exit vector with their destination , they can dogleg out.

As for combat, ships have "psuedo-velocity" and turn using conventional thrusters. This drastically reduces the number of endpoints, although I still think its a little high.

Since turning is accomplised by normal drives, and stutterwarp speed takes a significant ammount of time to alter (I'll regard it as fixed for our purposes), you can treat the enemy vessel as if it were G-maneouvering.

Using the TNE 20 tons per MW number (HEPlaR), a Kennedy maneuvers at about (150x20 = 3,000 tons, ~12,000 tons normal load = 0.25G) 0.25G. The Suffren is about the same, Konstantin a bit better (but old tech, som perhaps less efficient), Aconit (MHD powered) much worse at only 0.05G.

I tried to include some maneuvering factor in one of my articles:

http://www.users.globalnet.co.uk/~dheb/2300/SG/Martel/BMLEMartel.htm

Bryn

 

[TKalbfus]

They don't. Once you cross the FTL threshold you're going so quickly that you can't even see other ships. The perps don't have to align their exit vector with their destination , they can dogleg out.

If they are in normal space between Stutterwarp jumps, they can be seen, they will reflect light and give off a therma-signature. The image that is seen of them might not be up to date, but it does indicate where they were. With powerful enough sensors an FTL ship can be tracked through deep space. Also after crossing the threshold the ship is going just above the speed of light, its velocity increases beyond that the further it pulls away.
Also consider this, a stutter warp spaceship may be traveling away from you at 365 times the speed of light or Warp efficiency 1, but its image will appear to be moving away from you at less than the speed of light, but more than half that speed! This is an optical illusion caused by the fact that the light reflected off and emitted by the receding FTL ship, still travels at the speed of light. Here is a concrete example.
A stutterwarp ship is moving away from you at Warp Efficiency 1 (365c). In 1/365th of a second, the ship is 1 light second (299,792,458 m). In 1 second + 1/365th of a second, you would see the starship moving away from you at a distance of exactly 1 light second (299,792,458 m), its no longer there of course, but thats where it appears to be. The Stutterwarp ship actually appears to be moving away from you at 99.5% of the speed of light (298,973,353 m/s). In reality, no onject moving directly away from you at below the speed of light will ever appear to be traveling at more than half the speed of light. This is the counter part to the optical illusion of an object moving directly toward you at just under the speed of light. An object moving toward you at 90% of the speed of light (269,813,212 m/s), will appear to be traveling at ten times the speed of light. (2,997,924,580 m/s)

 

[aramis]

Originally posted by Tom Kalbfus:
</font><blockquote>quote:</font><hr /> They don't. Once you cross the FTL threshold you're going so quickly that you can't even see other ships. The perps don't have to align their exit vector with their destination , they can dogleg out.

If they are in normal space between Stutterwarp jumps, they can be seen, they will reflect light and give off a therma-signature. The image that is seen of them might not be up to date, but it does indicate where they were. With powerful enough sensors an FTL ship can be tracked through deep space. </font>[/QUOTE]Agreed. FTL ships CAN BE SEEN, especially if yo're going FTL in parrallel trailing course.

 

[TKalbfus]

Aramis said,

Agreed. FTL ships CAN BE SEEN, especially if yo're going FTL in parrallel trailing course.

Not only that, and FTL ship can slow down and stop, look back and see itself approaching in reverse time sequence on its own sensors. The FTL ship has out run the light that was reflected off it, and that it emmitted, it can look back and see a prior image of itself before it slowed down, because that light is only now reaching its sensors, it sees the stutterwarp blink out, a small amount of time passes and it sees another image of itself further way and prior to the moment of the first image, this process repeats itself over and over again, each image is further away, revealing a prior moment in time, until the ship exceeds the sensors capabilities. Now the rule for the apparent velocity is this:

For an object moving directly away at an FTL speed, the velocity appears to be ...
the speed of light (c) - the speed of light (c) / the speed of the spaceship (v)

or

Vapp = c - (c/v)

For an FTL object moving toward you, you don't see anything until it arrives or passes you, but then you see a reverse time image of the spaceship that appears to be moving at ...

Vapp = c + (c/v)

In this way you can tell whether an FTL ship is moving away from you or has already arrived and its image is moving away from you.

 

[kafka47]

On a lighter note, I just found a link for the earlier discussed and much maligned Cthulhu drive.