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Jump from aground

Carlobrand

SOC-14 1K
Marquis
Jeng Abri is suicidal. Unfortunately, his captain does not realize that - but he'll find out shortly. Jeng is the chief, and only, engineer on duty in the engine room of the free trader when his captain calls down to prepare for takeoff. Jeng, reflecting on life, decides to seek the answer to a question that has been bugging him for most of his career. He activates the jump drive - while the ship is aground, docked at the starport.

And ...

What happens next? Not from the engineer's point of view: short of some fantastick stroke of luck, his role in the game is at an end, as are those of the captain and everyone else on the ship. What happens to the dockworker stowing fuel lines outside the ship? What happens to the young lady watching her beau off from the observation window of the starport docking bay? What happens to the neighboring ship in the next berth?
 
Boy this got my juices flowing :devil:
I'm creating results chart of what happens to the ship people in and out of the ship and other fun :devil: details.

In short though N/A at A, B & most C starports due to port controlled safety interlocks.

For outside of the ship the question would be what kind of jump field does the ship have (grid, bubble, other).

IF they survive, which is possible, the campaign has just entered a whole new realm. :devil:

The real question is do you as the GM want them to survive or is this how you want to end the game/campaign? :confused:
 
By T5 it probably wouldn't work due to interference - p373 "if during the process of initiation a Jump objects larger than the ship are in (or partially in) the ship’s jump field, the Jump fails. The Jump Drive receives Mishap damage.".

Since the ground the ship is sitting on and the atmosphere surrounding it counts, the drive would probably overload and not work. Wether it fails with a bang or a fizzle is up to the GM.

If the (mis)jump was allowed - then it would depend on wether you have plates, a grid or bubble.

A grid wouldn't affect anyone not touching the hull, plates would probably clean up the dock worker but no further, while a bubble would make a real mess.
 
Someone must have had you in mind. From the DGP Starship Operators' Manual Vol. 1.:

Jumping In a Gravity Well: While it is possible to enter jumpspace from anywhere (even sitting in a docking bay on the surface of a planet), there are certain practices which are recommended. - pg.13

In Megatraveller there is a lanthanum grid which surrounds the ship, the warp bubble hovers 1 meter from the grid. if there is a hull breach greater than 1 meter in size the bubble may intrude the phyisical space of the ship to keep the bubble intact. People go insane or die if they get within a few centimeters of the bubble.

I would start off with anything within 1 meter of the ship is toasted. The field breaks up the ground, kills everyone within a meter of the warp bubbl, maybe takes the atmosphere of the hanger into jumpspace.
 
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As far as what the dockworkers might see. A normla jump looks like this:

Observing Jumpspace Transition: To an outside observer, the entry of a ship into jumpspace is a most spectacular sight. It begins when the jump grid is first warmed up during the preparation for jump. The lanthanum traces in the hull slowly build up a faint blue-white gloW which forms a crisscross pattern across the surface of the ship. When the Captain orders the ship into jumpspace, the increased energy flow causes the pattern to suddenly become so bright it is almost painful to look at with the naked eye. A blue "energy haze" forms about the ship as the weave of the targeted jumpspace level is disturbed. Finally, too last for the eye to follow, the ship seems to collapse into a line along its central axis and quickly shrinks to a brilliant point of light before it vanishes completely. Only the blue haze remains to mark the passage into jumpspace, and that quickly fades.
To an observer aboard a starship, the process is far less sp9ctacular. One second he is looking at a normal star field with a glare from the energized lanthanum hull grid clearly visible; lhe next, he can see only the undulating gray ·nothingness · of the protective jump field. - pg. 14
 
Using HG2, calculate the EPs that are stored in the jump capacitors.

Now release that energy in a blast of hydrogen plasma...
 
Misjump: Each time the ship engages in a jump, throw 13+ for a misjump: Apply the following DMs: +1 if using unrefined fuel (and not equipped to do so), +5 if within 100 planetary diameters of a world, +15 if within 10 planetary diameters of a world. If the result is 16+, then the ship is destroyed - Book 2 Starships (1979 edition) pg 6

In CT, the ship is always destroyed by RAW as there is no DM's mentioned which reduce the the roll. Barring house rules or something I have not found yet, the minimum roll is 17. So always destroyed ship...

Ah, but the question is where is the debris.
If it goes into JumpSpace, there may be that displacement inrush of air due to all 1400+ kiloliters of matter disappearing.

If the destroyed ship stays in normal space:
As far as energy is concerned: from High Guard, Jump capacitors store 36 EP per ton.

Jump capacitors = .005 * Jump Number * Tonnage (already included in the Jump Drive).

So barring additional capacitors your standard Type S Scout and Type A Free Trader store 36 EP. The only conversion I have found is from Striker. Comparing it is implied perhaps that 1 EP ~ 250 megawatts so the energy coming from the capacitors may be on the order 9 gigawatts. Does that help?
 
[FONT=arial,helvetica]If the destroyed ship stays in normal space:
As far as energy is concerned: from High Guard, Jump capacitors store 36 EP per ton.

Jump capacitors = .005 * Jump Number * Tonnage (already included in the Jump Drive).
[/FONT]
So barring additional capacitors your standard Type S Scout and Type A Free Trader store 36 EP. The only conversion I have found is from Striker. Comparing it is implied perhaps that 1 EP ~ 250 megawatts so the energy coming from the capacitors may be on the order 9 gigawatts. Does that help?

Despite the name, "Energy Points" are actually rating "Power" (Energy per unit time), not Energy (Watts are a measure of Power, not Energy). And depending on how quickly the power is released by the capacitor will tell you how much actual energy is released (1.0 Watt-second = 1.0 Joule). If 9.0 GW is the discharge rate (and 9.0 GW were provided by the capacitor (and totally discharged) over the course of a full second (i.e. a 1 second discharge time)), 9.0 GW-sec (Gigajoules) of energy would be released (and that would be the energy storage capacity of the capacitor). If the power were released over the span of a millisecond or so (i.e. at a 9.0 GW discharge rate over a 1 millisecond discharge time, and totally discharged during that timeframe), the energy released would be 1/1000 of that, or 9.0 Megajoules (MW-sec) (which, again, would be the total storage capacity of the capacitor).

The question becomes, how quickly does a Jump Capacitor discharge under normal operation, as that will determine the actual amount of energy stored in the capacitor.

On the other hand, if 1 EP (for capacitor purposes) is considered to be equivalent to 250 MW-turns of energy (1 turn = 20 minutes), then the 36 EP capacitor is storing 9.0 GW-turns. Converting, this is equal to (20min/turn) x (60sec/min) x 9 GW-turns = 10800 GW-sec (or 10.8 Terajoules total energy capacitance). The fact that a ship can use energy in its capacitors during combat to power itself from energy absorbed from Black Globes (see) would tend to favor this latter interpretation.

Note that 1.0 ton of TNT is ~4.184 Gigajoules (1.0 kiloton of TNT ~4.184 Terajoules). By comparison, Little Boy (Hiroshima) was 16.0 kilotons (67 Terajoules), and Fat Man (Nagasaki) was 21.0 kilotons (88 Terajoules).


NOTE: Please check my logic/math - I am at work and keep getting interrupted by little nuisance things at random moments, so I may have made an error in my analysis.
 
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On the other hand, if 1 EP (for capacitor purposes) is considered to be equivalent to 250 MW-turns of energy (1 turn = 20 minutes), then the 36 EP capacitor is storing 9.0 GW-turns.

In MT for M-drive the wattage listed would be considered as per second. As that is how the M-drives are spec'd and designed. Acceleration per second for a given size & power requirement. So, best to carry that for all ship systems.
 
I did not study chemistry or physics. I try to find a real life data point(s) which matches a gaming data point. So take a look at this, see how silly it is. I am more concerned about the gaming effects. If the correlation of energy to explosive value holds true....
The Type S Scout is holding ~ 10.8 terajoules of energy and 1.0 kiloton of TNT ~4.184 Terajoules, then the capacitors hold about 2.581262 ktons worth of TNT explosive energy. If that is the case...

In Striker Charts and Tables pg. 46, there are the Demo Charge tables, A demo charge is 10kg. While the destructiveness of a demo charge varies by TL, I will assume that it is at the lowest power, at TL 5-6 for 10 demo pts per charge. The 2.581262 of TNT = 2581262 kg of TNT. This may be the same as about 258126 Demo Charges. This equates to 2.5 million demo points. This in turn equates to a penetration 84 attack in Striker.

As far as what gets affected:
Code:
Penetration	Range
84		Contact with explosive. Penetrates 1400cm hard steel
44		Up to 10 meters away.  Penetrates 43.6cm hard steel
36		Up to 20 meters away. Penetrates 21.8cm hard steel
28		Up to 30 meters away. Penetrates 10.9cm hard steel
20		Up to 40 meters away. Penetrates 5.45cm hard steel
12		Up to 50 meters away. Penetrates 2.75cm hard steel
4		Up to 60 meters away. Penetrates 0.75cm hard steel
For reinforced concrete double the cm. For me, from a gaming perspective, there is going to be a ~ 28 meter crater in the starport. Other objects may tumble into the crater but perhaps not suffer as much damage.
For personnel, even in TL 14 battle dress, you are dead up to 30 meters away, based on the minimum possible damage roll (2) + penetration (28) - armor (18) = 12 (dead) if no other factor is involved. After that you might survive.

From a High Guard standpoint.
Weapon attacks themselves can be translated to EP. 36 EP =
Code:
Number of attacks
x factor	Turret or Bay Type
4x9		Beam
4x9		Pulse
4x9		Plasma
4x9		Fusion
1x7		Particle Attack
1x9		Non-nuke missile attack
1x2		Meson attack
Don't know how much armor the atmosphere provides. If any.
 
Interesting. Options are:

1) nothing, due to port-controlled safeties (technically not mentioned in canon, but a reasonable precaution.) In T5, nothing, but the drive takes damage in the attempt.

2) The jump capacitors let go, releasing - I'm not sure where that 10.8 terajoules comes from - 250 megawatts x 1 turn (20 minutes in High Guard) = 300 billion joules is one EP, if I understand it right, which is equivalent to 71.7 tons of TNT if you can get it to express itself as an explosion, and it takes two turns to charge up a capacitor for a jump, so it's 1 EP for two turns per 100 dTons times jump number. Jump-2 scout goes for 286.8 ton blast. :ssb: :toast:

And then of course there's the question of how much of that energy manages to exit a hull equivalent to over a foot of steel. My money says you get a massive blast out the airlock and viewports as the interior gets vaporized, maybe massive blast from seam edges as the hull gives along weak points, and you're left with an empty, distended hull glowing deep red and igniting fires in the near vicinity from the heat being given off by the hullmetal.

Or maybe an empty, distended half-a-hull as the upper half is launched upward by the blast.

Or maybe an empty, distended missile as the aft hull wall breaks free at the edges and is launched backward while the ship driven forward like a giant hypersonic bullet.

Or some combination thereof.

3) The ship jumps, maybe never to be seen again, or at least not as an intact ship. As described in SOM, it emits a blue glow then appears to shrink rapidly - taking everything within a meter of the hull with it and possibly resulting in a thundrous crack as air rushes in to replace the departed volume. (However, Megatraveller, on which SOM is based, tells us the odds of the ship being destroyed are absurdly low; see below.)

A CT scout gets a DM to its roll, so minimum possible roll is a 2 +15 for being inside 10 diameters -2 for being a scout = 15, a 1 in 36 chance of misjumping instead of being destroyed by event #2 or event #3 above.

An MT scout gets no bonuses, but it doesn't really need them. In MT, a jump within 10 diameters is a formidable hazardous task. Formidable means you need 15 on 2d6, impossible without some DMs in your favor. Exceptional failure occurs on 13 or less (before the DMs), and of course a natural 2 is a fumble. DMs for Engineering and high education (1/5 of the stat, round down; usually at least 1 point for the typical engineer). A skilled engineer (Engineer-3, +1 to 2 for education = +4 to +5) might actually pull it off, though it's a real long shot.

Failure presumably means nothing happens, you fail to jump with no other consequence; maybe you realize impending doom and slap the emergency shutdown. Presumably the fuel gets used, so you've got that problem to deal with.

Exceptional failure means another 2d6 roll: superficial mishap 14/36 times, minor mishap 20/36, major 1/36 (reroll 1/36).

Fumble (1/36 regardless of DMs) means a 3d6 roll: superficial mishap 20/216 times, minor mishap on 88/216, major on 88/216, destruction on 20/216.

Superficial = jump relativity error, ship arrives on target but takes 1d6+4 days to get there instead of the usual 6-8.

Minor = jump relativity error (1d6+4 days in jumpspace) plus arrives 1d6x8 hours farther away from the target.

Major = jump relativity error (1d6+4 days in jumpspace) plus misjump: the classic 1d6 6-sided dice to find parsecs travelled and 1d6 for random direction.

Destruction = "the ship is destroyed," which is presumably #2 or #3 above.

In other words, if you jump straight from the berth in MegaTraveller and suffer an exceptional failure or fumble, you'll still arrive at your desired system about 95.8% of the time, just a couple days off and a day or two out from it. Odds of a misjump are about 3.9%. Odds of destruction are 0.257% - about once in 400 attempts. Your worst fear, other than misjump, is actually that you suffer a simple failure and don't get anywhere: in a bizarre twist, your odds of getting there are actually better if you let the steward handle the jump, 'cause he has absolutely no chance of a regular failure, does no worse on the mishap table and has no more chance of a fumble than the engineer. Ooh, that's odd - I hadn't realized that. :oo:

Just have a plan in place for a misjump, 'cause that can ultimately be as fatal as being inside an exploding ship - just slower.
 
2) The jump capacitors let go, releasing - I'm not sure where that 10.8 terajoules comes from - 250 megawatts x 1 turn (20 minutes in High Guard) = 300 billion joules is one EP, if I understand it right, which is equivalent to 71.7 tons of TNT if you can get it to express itself as an explosion, and it takes two turns to charge up a capacitor for a jump, so it's 1 EP for two turns per 100 dTons times jump number. Jump-2 scout goes for 286.8 ton blast. :ssb: :toast:

If the destroyed ship stays in normal space:
As far as energy is concerned: from High Guard, Jump capacitors store 36 EP per ton.

Jump capacitors = .005 * Jump Number * Tonnage (already included in the Jump Drive).

So barring additional capacitors your standard Type S Scout and Type A Free Trader store 36 EP.


The 10.8 Terajoules is the energy in a capacitor that can provide 36 EP (not 1 EP). It was determined upthread that the ship in question would have capacitors storing energy that could provide 36 EP of power. (300 Gigajoules x 36 = 10.8 Terajoules).
 
Once you have equated EP to TNT you simply find an analgous value for the game in question. As an example if it is a 268.8 ton blast, in Megatraveller Referee Manual pg 103, the Demolition Table there indicates a penetration value of 100 or a breach penetration of 70.

2) The jump capacitors let go, releasing - I'm not sure where that 10.8 terajoules comes from - 250 megawatts x 1 turn (20 minutes in High Guard) = 300 billion joules is one EP, if I understand it right, which is equivalent to 71.7 tons of TNT if you can get it to express itself as an explosion, and it takes two turns to charge up a capacitor for a jump, so it's 1 EP for two turns per 100 dTons times jump number. Jump-2 scout goes for 286.8 ton blast. :ssb: :toast:
The 10.8 terajoules comes from
Despite the name, "Energy Points" are actually rating "Power" (Energy per unit time), not Energy (Watts are a measure of Power, not Energy). And depending on how quickly the power is released by the capacitor will tell you how much actual energy is released (1.0 Watt-second = 1.0 Joule). If 9.0 GW is the discharge rate (and 9.0 GW were provided by the capacitor (and totally discharged) over the course of a full second (i.e. a 1 second discharge time)), 9.0 GW-sec (Gigajoules) of energy would be released (and that would be the energy storage capacity of the capacitor). If the power were released over the span of a millisecond or so (i.e. at a 9.0 GW discharge rate over a 1 millisecond discharge time, and totally discharged during that timeframe), the energy released would be 1/1000 of that, or 9.0 Megajoules (MW-sec) (which, again, would be the total storage capacity of the capacitor).

The question becomes, how quickly does a Jump Capacitor discharge under normal operation, as that will determine the actual amount of energy stored in the capacitor.

On the other hand, if 1 EP (for capacitor purposes) is considered to be equivalent to 250 MW-turns of energy (1 turn = 20 minutes), then the 36 EP capacitor is storing 9.0 GW-turns. Converting, this is equal to (20min/turn) x (60sec/min) x 9 GW-turns = 10800 GW-sec (or 10.8 Terajoules total energy capacitance). The fact that a ship can use energy in its capacitors during combat to power itself from energy absorbed from Black Globes (see) would tend to favor this latter interpretation.

Note that 1.0 ton of TNT is ~4.184 Gigajoules (1.0 kiloton of TNT ~4.184 Terajoules). By comparison, Little Boy (Hiroshima) was 16.0 kilotons (67 Terajoules), and Fat Man (Nagasaki) was 21.0 kilotons (88 Terajoules).


NOTE: Please check my logic/math - I am at work and keep getting interrupted by little nuisance things at random moments, so I may have made an error in my analysis.
The computation of Energy Points comes directly from CT High Guard pg 31.
The capacitors contained in the ship's jump drive may be used to store this energy; additional capacitors may also be purchased. The jump drive capacitors mass .5% of the ship's mass, per jump number; for example, a drive capable of jump3 will include capacitors equal to 1.5% of the ship's mass. Additional capacitors may be purchased at MCr4.0 per ton. One ton of capacitors (in a jump drive or not) will hold 36 EPs.
Both a Type S and a Type A have 1 ton of capacitor and so 36 EP.
As the capacitors must be fully charged to jump, that means at the moment of jump there must be 36 EP. That part is RAW, well in CT anyways.
 
I think the ship and everything within 1 meter pops into jumpspace and there is an implosion as air rush in to fill the vacuum left behind. I don't know how violent the implosion would be, but I doubt it would be in the same class as any sizable explosion.



Hans
 
And then of course there's the question of how much of that energy manages to exit a hull equivalent to over a foot of steel.
But, the explosion isn't necessarily inside the hull - the jump grid/bubble is outside the hull. We mentioned the capacitors, but that doesn't mean the capacitors are the means of expressing the kaboom. What if it's the jump field that carries the energy? Conceivably, you could have everything outside the ship experience the explosion, but the hull stops it from impacting inside the ship.

Personally, I would have the PP and the jump drive both give off massive amounts of neutron radiation inside the hull while the explosion took place out side the hull. So, your end result would be an empty shell of a ship misjumped somewhere, and a massive hole/crater where it used to be. (Along with ensuing radiation and such.)
 
I once figured the chance of success when doing this. If using the 'simple gravity' model then from an Earth-like world the chance of success in MT is Formidable+2. (Proof here.) Failure could mean the ship explodes but this is not guaranteed.

Assuming the ship doesn't explode then, IMTU, for those 'left behind' I think there would be three different effects to take into account.
  • First, there would be the jump flash. Probably sub-nuclear in strength but still pretty nasty to those exposed in the immediate area.

  • Second, the OP didn't say if this was in atmosphere or not. If there was then there would be a sudden air implosion equal to the size of the jump field. This would cause a shock wave radiating out from that point.

  • Third, anyone in close proximity, who wasn't killed in the flash or implosion, would have to contend with the psychological effects of momentary exposure to jumpspace. I assume the unshielded effect will reduce with distance according to the inverse square law.

The psychic effect would travel fastest (near instantaneous speed), making it the first warning to duck that some people get. A split second behind this, at light speed, would be the flash. And lastly, at the speed of sound, would be the implosion shock wave.

Having the ship explode might be preferable.
 
For all, perhaps recompute your energy requirements. I have been reading further:
Jump Governor: When the command is given to jump, energy from the zuchai crystals is directed into the jump governor. This device, which incorporates its own highly accurate computer system, is linked to the ship's main computer system for guidance and backup. With utmost precision, the governor applies initial bursts of energy (about 20% the the charge) in the proper sequence· to the lanthanum net (which is incorporated in the hull of the ship), thereby "warming up the grid". At this point, if anything out the ordinary is detected, it is possible to abort the jump.
The next step, Ihe transition phase, commits the craft to the jump. It is impossible to abort the jump once transition has started.
The transition phase begins when the jump governor feeds the remaining portion of the energy stored in the zuchai crystal array (the remaining 80% of the charge) to the hull grid, opening the weave to the desired jumpspace level. Once this opening is made, the craft tumbles into the breach and leaves normal space. - Starship Operator's Manual Vol. 1 pg 13
So...maybe 80% (28.8 EP, 8.64 terajoules) is only in play. As to where the energy is in the transition step:
The lanthanum network spread throughout the hull turns blue, or rather the ship does all along its lines, The thing looks like one of those computer drawings that naval architects use. It doesn't light up all at once, either, but extends from one point to another, however the navigator set it up for whatever jump vector he's trying to hit.
So once this grid shape is formed, the whole area around the hull starts glowing this same shade of blue. A couple seconds later and the ship's gone, and this blue patch just shrinks down into a point belore fading completely. - Starship Operator's Manual Vol. 1 pg 11
So in a normal jump, the grid is "saturated" as it were before the weave opening occurs. The phases of jump are listed from the book as follows:
Pre Jump
Vector Comp
Charge Up

Transition
Weave Open
Cross-Over
Tumble
Weave-Close

Jump Space
Travel (1 week)

Post-Jump
Emergence
Normal Space
 
Depending where in the jump start-up cycle things went wrong, some of that energy will be diverted into bending space time and opening the entrance to jump space. If things go bang after that some of the energy and bits of the ship might be shunted into jump-space.

Bit less of a bang on the landing pad
 
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