One shot Jump Drives

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Reynard
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Re: One shot Jump Drives

Postby Reynard » Sun Mar 10, 2019 2:20 pm

I was thinking that too. Cost and time as a system repair and the price should be more for each extra jump as the engine degrades. Definitely not a runaround for a cheap engine.
baithammer
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Re: One shot Jump Drives

Postby baithammer » Sun Mar 10, 2019 10:24 pm

The riders chief weakness is its inability to remove itself from a system where its outmatched, the one-shot drive gives it an exit while still allowing the rider to maintain a more efficient use of its displacement.

The use of the breakaway hull gives it the ability to be restocked by the tender ( Along with jump fuel), without having to go to a starport.

The role the riders play is that of assault, where longer jumps aren't required by the riders themselves. ( Not so good for patrol duties or strike missions.)
Sigtrygg
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Re: One shot Jump Drives

Postby Sigtrygg » Sun Mar 10, 2019 10:51 pm

Why not just use a jump one drive with three allocations of fuel efficient?
baithammer
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Re: One shot Jump Drives

Postby baithammer » Mon Mar 11, 2019 1:01 am

About 6x as expensive for the Fuel Efficient drive which is a tad expensive for something you'd only use in emergencies.
Condottiere
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Re: One shot Jump Drives

Postby Condottiere » Mon Mar 11, 2019 2:02 am

At a seventy five percent discount, I think I've explored most of the possibilities you could use this variant.

1. Giant kinetic kill jump torpedo.

2. Emergency rescue lifeship.

3. One way trip, possibly penal colony or exile; because with a normal colony, ou might want to set up a line of communications or trade route.

4. Strategic bomber mission to a heavily defended planet.

It's in the realm of possibilities to use it twice on a short hop; with three you're pushing it.

For more normal usage, the attraction would be for starships that are rarely used, say once a year; nothing is stated whether the jump drive can be refurbished, and we don't know why it's forcibly being obsolescenced.

If it's because it uses a zucchini rather than a Zuchai crystal.

I'd be in favour of spending time and money rebuilding the drive, but it's hard to say without understanding what's different between it and a normal jump drive. It's likely the author just added the concept in because it sounded interesting.

The way I look at it, it would depend if the deterioration is in the core, or jump capacitors, or both; if it's the capacitors, losing capacity would make it rather likely that for longer jumps they'd definitely blow.
baithammer
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Re: One shot Jump Drives

Postby baithammer » Mon Mar 11, 2019 4:51 am

Most likely the parts for the jump drive itself have relaxed standards which essentially result in higher wear and tear.

As to the refurb, the breakaway hull pod allows for the majority of its components to be reused with the drive being the only thing that needs to be replaced. ( And given that its for emergency use will most likely go unused for a long period of time.)
phavoc
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Re: One shot Jump Drives

Postby phavoc » Mon Mar 11, 2019 2:45 pm

Like many things it sounds better on paper than it would (most likely) work out in practice.

For riders, jumping out 1 hex could potentially leave them stranded in deep space. Assuming that they had a pre-arranged rendezvous point, the tenders would have to first jump to the rendezvous point AND have enough fuel to jump out to a safe refueling haven.

The cost of the drive and the complexities of the operation would make this an unlikely scenario in my opinion. The credits for the drives would be better spent elsewhere.
Sigtrygg
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Re: One shot Jump Drives

Postby Sigtrygg » Mon Mar 11, 2019 6:58 pm

baithammer wrote:
Mon Mar 11, 2019 1:01 am
About 6x as expensive for the Fuel Efficient drive which is a tad expensive for something you'd only use in emergencies.
People are talking about breakaway hulls and replacing the single use drive, a regular fuel efficient drive would be more economical in the long term.
Sigtrygg
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Re: One shot Jump Drives

Postby Sigtrygg » Mon Mar 11, 2019 7:03 pm

phavoc wrote:
Mon Mar 11, 2019 2:45 pm
For riders, jumping out 1 hex could potentially leave them stranded in deep space. Assuming that they had a pre-arranged rendezvous point, the tenders would have to first jump to the rendezvous point AND have enough fuel to jump out to a safe refueling haven.

The cost of the drive and the complexities of the operation would make this an unlikely scenario in my opinion. The credits for the drives would be better spent elsewhere.
Your tender would jump to an outsystem Kuiper belt object (or even an hypothetical Oort cloud object) and start refueling, your riders would jump out to meet it if the situation warrants it.
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Re: One shot Jump Drives

Postby baithammer » Mon Mar 11, 2019 7:30 pm

For riders, jumping out 1 hex could potentially leave them stranded in deep space. Assuming that they had a pre-arranged rendezvous point, the tenders would have to first jump to the rendezvous point AND have enough fuel to jump out to a safe refueling haven.
The tender would have an extra jump 1 and have a prearranged rendezvous point, hence why the riders are best used in assaults rather than strike missions.
The cost of the drive and the complexities of the operation would make this an unlikely scenario in my opinion. The credits for the drives would be better spent elsewhere.
And you'd lose efficient use of displacement and raise the cost of the rider. ( Not to mention would leave the riders vulnerable and less useful.)
People are talking about breakaway hulls and replacing the single use drive, a regular fuel efficient drive would be more economical in the long term.
It would be wasting credits as the drive isn't used except during emergencies which also becomes less likely as the riders are utilized for assault rather than strike missions.
phavoc
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Re: One shot Jump Drives

Postby phavoc » Mon Mar 11, 2019 7:59 pm

Sigtrygg wrote:
Mon Mar 11, 2019 7:03 pm
Your tender would jump to an outsystem Kuiper belt object (or even an hypothetical Oort cloud object) and start refueling, your riders would jump out to meet it if the situation warrants it.
In that case it would probably be better to jump with tanker support, or have tankers waiting at a pre-arranged deep-space rendezvous. Assuming you spend the money/space to upgrade the M-drives on your riders, they could simply accelerate to the rendezvous point while the enemy either chases them or allows them to disengage. Sure, the enemy could jump, but their destination would be locked in for a week while the riders could veer off and be completely out of sensor range. The side holding the system would have to make a gamble on if the riders are leading them into a trap, or drawing off the defenders while a second fleet is waiting to emerge from jump space to a weakened defense.

It could take week(s) for a rider to gather enough resources to refuel depending on the number of ice objects available. Plus what tenders are equipped to refuel by grabbing hordes of small ice objects, melting them down and converting? Or else for your hypothesis that they would be able to find a large enough object to refuel from without having to gather up smaller ice asteroids, then they'd need to know ahead of time, through scouting, just where those large ice objects are located. If the enemy tracked them and dispatched a force to catch the cruiser then you'd still lose your tender, and possibly the riders as well.

You'd also have to hope that an enterprising enemy has not mined or put some sort of passive defense on large enough objects to be used as refueling sources. Or else they haven't used them as target practice over the years, leaving instead shattered remains.

Of course either of these scenarios are possible, but are they practical? The British proposed 'unsinkable' iceberg carriers to provide cover in the North Atlantic. While proven possible using the technology at hand in scaled tests, they never went beyond paper ideas.

One-time drives have potential uses, but it's very debatable whether they would actually work well when you have more regular options. They certainly would cause an enemy some consternation the first time they got used and nobody was expecting that. But then the enemy would know that some, or all, of a class of ships had them and the surprise would end there.
phavoc
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Re: One shot Jump Drives

Postby phavoc » Mon Mar 11, 2019 8:06 pm

baithammer wrote:
Mon Mar 11, 2019 7:30 pm
For riders, jumping out 1 hex could potentially leave them stranded in deep space. Assuming that they had a pre-arranged rendezvous point, the tenders would have to first jump to the rendezvous point AND have enough fuel to jump out to a safe refueling haven.
The tender would have an extra jump 1 and have a prearranged rendezvous point, hence why the riders are best used in assaults rather than strike missions.
Are you proposing that tenders would have a one-time jump drive installed, or they would be carrying additional fuel to allow them to do a jump-1 without their riders docked?
baithammer wrote:
Mon Mar 11, 2019 7:30 pm
The cost of the drive and the complexities of the operation would make this an unlikely scenario in my opinion. The credits for the drives would be better spent elsewhere.
And you'd lose efficient use of displacement and raise the cost of the rider. ( Not to mention would leave the riders vulnerable and less useful.)
Adding in either a 1-time use drive and the fuel for that, OR adding in additional stored fuel AND the additional costs that entails for the extra tonnage also raises the cost of the rider. Any of the options discussed raises the cost of a rider (efficient use of displacement is a conversation in and of itself).
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Re: One shot Jump Drives

Postby Sigtrygg » Mon Mar 11, 2019 8:19 pm

Your tender jumps to the Oort cloud of the system to be attacked.

It manufactures drop tanks for its riders using its maker shops and refuels.

The riders make a jump 1 insystem using the drop tanks, with enough onboard fuel for an emergency jump out again or if they win the tender can join them.
Reynard
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Re: One shot Jump Drives

Postby Reynard » Mon Mar 11, 2019 9:49 pm

Now you all did it! I dug up my Battle Rider game to see what the strategy and tactics was envisioned. Need to look for other sources. Seems though travelling to and from the ort and Kuiper regions is a bit extreme. Can jump flash be detected? Light speed moves much faster than any maneuver drive. How long does it take to gather enough fuel out there? How much fuel is wasted to travel to and from the edge of a system?
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Re: One shot Jump Drives

Postby AnotherDilbert » Mon Mar 11, 2019 10:01 pm

Yes, jump flash is easily detected, see Stealth Jump, HG p48, but only in sensor range.

Riders are only really effective in CT where extra jump drives are not necessary, since the tenders can be screened in the reserve.

In MgT Riders are not effective, since you need the Hull points from a large hull to survive. A battleship has much more Hull points per MCr than a rider tender combination. A rider tender pair might be effective if you need very high jump capability, say J-6.
baithammer
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Re: One shot Jump Drives

Postby baithammer » Mon Mar 11, 2019 10:46 pm

In MgT Riders are not effective, since you need the Hull points from a large hull to survive. A battleship has much more Hull points per MCr than a rider tender combination. A rider tender pair might be effective if you need very high jump capability, say J-6.
Mgt riders can be effective as your bringing more targets and firepower to the engagement and a high jump tender is very inefficient in cost and displacement.
Your tender jumps to the Oort cloud of the system to be attacked.
And because of the strategic value of the Oort cloud will most likely be monitored and inform system defense of where the tenders are.
It manufactures drop tanks for its riders using its maker shops and refuels.
Takes way too much time to manufacturing anything when in hostile territory.
Are you proposing that tenders would have a one-time jump drive installed, or they would be carrying additional fuel to allow them to do a jump-1 without their riders docked?
Extra Jump -1 fuel so the tender jumps in ( Jump -4), undocks the riders and jumps out to a rendezvous point.
Adding in either a 1-time use drive and the fuel for that, OR adding in additional stored fuel AND the additional costs that entails for the extra tonnage also raises the cost of the rider. Any of the options discussed raises the cost of a rider (efficient use of displacement is a conversation in and of itself).
Remember the riders Emergency drive is for emergency use, so in most cases will not be used.

This means the much lower cost of the drive, which besides jump fuel is the only expended item is a better value than a full drive that will hardly ever be used.
But then the enemy would know that some, or all, of a class of ships had them and the surprise would end there.
Which is covered by the use of rider fleet, which is assault and not the initial strike into system that regular warships would be used for.

The emergency drive also rarely would be used as the rider fleet as I mentioned early would be in the assault phase of operations.
phavoc
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Re: One shot Jump Drives

Postby phavoc » Mon Mar 11, 2019 11:00 pm

baithammer wrote:
Mon Mar 11, 2019 10:46 pm
And because of the strategic value of the Oort cloud will most likely be monitored and inform system defense of where the tenders are.
Well, if the Oort cloud is a shell around a star system it would take a great number of satellites to monitor the whole thing.

baithammer wrote:
Mon Mar 11, 2019 10:46 pm
Remember the riders Emergency drive is for emergency use, so in most cases will not be used.

This means the much lower cost of the drive, which besides jump fuel is the only expended item is a better value than a full drive that will hardly ever be used.
You still have to pay for it to start, thus the cost is embedded once installed. Not using it just means you don't need to pay to replace it.
baithammer wrote:
Mon Mar 11, 2019 10:46 pm

Which is covered by the use of rider fleet, which is assault and not the initial strike into system that regular warships would be used for.

The emergency drive also rarely would be used as the rider fleet as I mentioned early would be in the assault phase of operations.
Not sure what that means. By definition you are assaulting an enemy system when you move in to it to engage the enemy. How often you have to retreat is going to be dictated by the battlefield and what the enemy has in the way of defenses when your fleet(s) arrive.

Depending on the system it's always going to be questionable whether or not a defender has enough ships to defend whatever it is you are wanting in a system as well as the local gas giant(s) and any other source of fuel. A gas giant that is two days away from the main planet gives the attacker two days to refuel. And unless you have sufficient static defenses no defender can afford to uncover what it is they are protecting.

Didn't the new Companion book have more about high guard operations, and just what makes a ship so vulnerable to attack? That's really important in this kind of discussion. It seems a ship can refuel in 6-8 hours, which almost guarantees an invader will have time to refuel before opposing forces could form up to repulse them.

The other thing here is that most fleets don't go anywhere without a fleet train tagging along (safely in the rear of course). This would be supply ships, repair vessels and tankers. Unless you are doing a hit-and-run raid, you will want your fleet train to be available as soon as the battle is over. With the time effect planned reinforcements for the defender are at least two weeks away.
baithammer
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Re: One shot Jump Drives

Postby baithammer » Mon Mar 11, 2019 11:19 pm

Well, if the Oort cloud is a shell around a star system it would take a great number of satellites to monitor the whole thing.
In system communications are considered instantaneous and the cost per monitor is rather low. ( Also hard to jam meson communications.)

Further, we also have access to gravitational analysis suite, which is ironically more effective in system than for intersystem monitoring. ( Greatly increases the detection of Jump signatures per monitor.)
Not sure what that means. By definition you are assaulting an enemy system when you move in to it to engage the enemy. How often you have to retreat is going to be dictated by the battlefield and what the enemy has in the way of defenses when your fleet(s) arrive.
The strike fleet scouts the enemy disposition and creates a beach head if able to, the assault fleet is called into break the system defense and consolidate the hold on it.

If the enemy can maintain opposition long enough for a relief fleet to be sent, the situation can dictate a retreat which a standard rider will be sol.
You still have to pay for it to start, thus the cost is embedded once installed. Not using it just means you don't need to pay to replace it.
Which is the point, as the cost for the emergency drive is 75% less than a standard drive and 112.5% less than a High Technology drive.
phavoc
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Re: One shot Jump Drives

Postby phavoc » Mon Mar 11, 2019 11:46 pm

If I did my math right, it takes 30 days for a radio signal to reach the Oort cloud (at a distance of 5,000 AU). A little digging at Nasa says the Oort cloud is believed to be spherical, at a distance of 5,000 to 50,000 AU around our solar system. So that's pretty much the end of trying to monitor the whole thing. Or even patrol it. It's supposed to be the source of comets, so if we assume that all the objects there are roughly comet sized, you'd probably not find objects the size of, say, Mimas, to refuel from. If that's the case, it's gonna be a lot of work to collect enough to refuel something as massive as a battle rider tender.

The distance is going to be too great to fully monitor it with Traveller sensors, especially if we are talking a depth of 45,000 AU!

As far as the strike fleet making a beachhead... that's not really a good analogy for space combat. There isn't a 'beach' to land on. Space is vast and you can't stop an enemy from entering your system. All you can do is place fleets a nodal points to what it is you feel you need to protect. The enemy will, by definition, be mobile. Defenders have the luxury of static defenses and monitors (which potentially would be candidates for one-shot jump engines). Attackers always have the luxury of timing and location to attack. Assuming the defenders have a safe place to fall back to rearm and repair, attackers have to bring everything with them. They can stooge around a system for a while, but unless there is something useful there it's not helpful other than tying up the defenders from moving forces out of the system. And staying too long means the defenders can potentially bring in forces that are overwhelming. Not many star-nations, even the Imperium, are going to have enough hulls in a war to just flit about and distract the enemy.

As far as cost, say you spent MCr100 for a jump drive for a 10Kton ship. That's still MCr 25 you have to spend for something you may not ever use. Granted, you may find yourself glad you have it in the first place (as will the fleets' bean counters), but whether or not it's justifiable is going to be academic. Since it's not present any other editions we've got nothing to really go by as far as how the fictional wars were fought (or might have been fought) with such a thing. Battle Riders have always been one of those items that are at risk anytime they are used in combat. And only the end of the battle tells you if it was worth the fight or not.
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Re: One shot Jump Drives

Postby Condottiere » Tue Mar 12, 2019 12:04 am

1. If the one shot jump drive is installed as an emergency exit strategy, the payload has to be worth the opportunity cost.

2. It's quite possible that you could try and lead naval guard units on a wild goose chase, permitting a second force to jump in and deal with the weakened defences, or more dastardly, jump back yourself, but that seems to over-complicate things.

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