Missing maintenance = misjump rule.

[RogerMc]

Running High and Dry solo (which it is actually well fitted for) it occurred to me that when you leave Walston you have to make the standard engineering test to jump somewhere - which is easy (4+) but has a -1 DM per month when routine maintenance has been missed.

While the scenario is not very specific quite clearly the former operators of the scoutship were not the types to maintain it properly - plus it has now been sat on a mountaintop for at least a few weeks and a lot of the important kit has been left outside to rot and be chewed at by the pet they abandoned in the crater.

Being Traveller I'd probably say that it has missed 1D or 2D months maintenance - which makes a misjump quite likely.

The same also applies to the various mysteriously abandoned ships that litter the Traveller universe that you are sometimes supposed to be able to restart and take over - with no crew aboard how long has the Kinunir or the Annic Nova gone un-maintained?

Or does a jump drive that sits unused even need maintenance? (which may solve my High and Dry problem).

[RogerMc]

Also on misjumps there is a -4 DM to the Engineer roll for being within 100 diameters of the planet.

So what about being within 10D of the planet or trying to jump from within its atmosphere?

In both cases a misjump should be pretty much certain - but you can imagine situations where even a 50% chance of ending up in empty space with no fuel to get you anywhere and all dying when you run out of air and food still beats certain destruction.

Also what about any blind jump where the astrogator has had no time to plot a proper course but things are so desperate they just hit the big red initiate jump button anyway.

Mechanically you'd presumably deal with that as a very hurried task with a formidable difficulty - so you are very likely to get a big negative effect from a failed astrogation test which is then applied as a negative DM to the engineer test and again makes a misjump much more likely.

[MonkeyX]

I’d say the DM penalty is for missed maintainance where the ship has still been in use. There’s a difference between leaving a pristine car on your driveway for a few months that driving one and meaning to get the clinking a scraping noise looked at.

[AnotherDilbert]

Being Traveller I'd probably say that it has missed 1D or 2D months maintenance - which makes a misjump quite likely.

The same also applies to the various mysteriously abandoned ships that litter the Traveller universe that you are sometimes supposed to be able to restart and take over - with no crew aboard how long has the Kinunir or the Annic Nova gone un-maintained?

Quite, in the absence of specific rules it is up to the Referee.

Or does a jump drive that sits unused even need maintenance? (which may solve my High and Dry problem).

I would guess that an unused J-drive needs less maintenance.

[AnotherDilbert]

Also on misjumps there is a -4 DM to the Engineer roll for being within 100 diameters of the planet.

So what about being within 10D of the planet or trying to jump from within its atmosphere?

In previous editions there has sometimes been a double DM if closer than 10 D, so I would use DM -8.


Note that with good skill, a little help (Expert systems, augmentation), and taking your time with both the Astrogation and the Engineering roll you can get quite good positive DMs to prevent misjump.

[Condottiere]

You could scale it in ten percent increments.

Maybe from two to twenty percent penalty.

[Rikki Tikki Traveller]

Also on misjumps there is a -4 DM to the Engineer roll for being within 100 diameters of the planet.

So what about being within 10D of the planet or trying to jump from within its atmosphere?

In both cases a misjump should be pretty much certain - but you can imagine situations where even a 50% chance of ending up in empty space with no fuel to get you anywhere and all dying when you run out of air and food still beats certain destruction.

Also what about any blind jump where the astrogator has had no time to plot a proper course but things are so desperate they just hit the big red initiate jump button anyway.

Mechanically you'd presumably deal with that as a very hurried task with a formidable difficulty - so you are very likely to get a big negative effect from a failed astrogation test which is then applied as a negative DM to the engineer test and again makes a misjump much more likely.

I always ruled that if you Jumped from within 10D you did misjump and your ship came out with a number of critical hits equal to 10-Diameter of the jump. Before there were critical hits, I said it couldn't be done at all - think Han Solo fleeing Tattooine - he pulls the lever and ... nothing... he was still inside 10D, once he got past 10D, the field formed and the drive can engage the Jump, with all the appropriate DMs...

[RogerMc]

Was also thinking of Battlestar Galactica jumping into and out of atmosphere in New Caprica - IIRC it arrives in flames with a big bang.

Somehow I don't think anything the size of a scoutship would survive that.

[RogerMc]

Was also thinking of Battlestar Galactica jumping into and out of atmosphere in New Caprica - IIRC it arrives in flames with a big bang.

Somehow I don't think anything the size of a scoutship would survive that.

[Reynard]

"Or does a jump drive that sits unused even need maintenance? (which may solve my High and Dry problem)."

Maintenance is for dealing for wear and tear usually from active use. Over long stretches of time, not just weeks or maybe even months, parts can age. Your sometimes mandatory Abandoned Prize Ship may have sat/floated for years or decades in less than pristine environmental conditions and could use a tune up before firing the jump engines.

I don't believe H&D considered the issue or it would have been written in as part of the adventure.

[RogerMc]

"Or does a jump drive that sits unused even need maintenance? (which may solve my High and Dry problem)."

Maintenance is for dealing for wear and tear usually from active use. Over long stretches of time, not just weeks or maybe even months, parts can age. Your sometimes mandatory Abandoned Prize Ship may have sat/floated for years or decades in less than pristine environmental conditions and could use a tune up before firing the jump engines.

I don't believe H&D considered the issue or it would have been written in as part of the adventure.

Another aspect is that the Scout/Courier in H&D is over 200 years old - which according to the logic of the core book old ships table should give it 20 or so 'quirks' - most of which are if stacked together several times over quite crippling.

And yet Traveller canon is full of ships far older than that which are still fully operational - hell don't the Darrians have whole squadrons of ancient ships older than the Third Imperium itself?

Speaking of which has anyone done an expanded a d66 Ship Quirks Table where most of them are actual quirks rather than operationally crippling defects to key systems like sensors and thrusters (or my favourite the radioactive power plant that will turn your game into a re-run of K19 The Widowmaker because you rolled a 2 on just one of those 10 or whatever 2Ds).

[Klooth Quethos]

Let's also not forget- though rare they may be- the occasional traveller who decides to misjump with distinct purpose. But yeah, anything within 10D is fraught with some very real issues.

[Condottiere]

If you do it within an atmosphere, you're displacing a lot more atoms than in space; and if we assume the process visually is a lot like Star Wars hyperjumping, not a lot of time for those atoms to get pushed aside.

[RogerMc]

If you do it within an atmosphere, you're displacing a lot more atoms than in space; and if we assume the process visually is a lot like Star Wars hyperjumping, not a lot of time for those atoms to get pushed aside.

So jumping out from within an atmosphere a whole lot of atoms suddenly disappear completely and other atoms are displaced violently to fill that sudden void?

Is that going to create a massive or even a nuclear explosion?

I so every starship in an atmosphere has the option to hit the jump button and go out with a bang and take the whole starport or even city with it - which would be a very useful plot device.

[Reynard]

When lightning disperses a lot of atmosphere almost instantaneously it doesn't cause massive surrounding destruction just a really big boom. A scout ship probably displaces far less volume.

[phavoc]

I have always assumed that a jumping too close to a planet (10D or less) just doesn't work. Too deep in the gravity well and the jump field simply won't form. No muss, no fuss, just nothing.

After the 10D limit you can form a field, but it's unstable the closer you are to the gravity well.

The original jump method had ships powering their jump grid built into their hull (lanthanum grid), so it basically popped itself into jump space. MGT has a bubble forming, though it's never been clear if the bubble is a sphere, or if the bubble is conformal around the hull. T5 gives a couple of variants.

[Rikki Tikki Traveller]

IF you allow jumping from inside the atmosphere, FINE, you cause a lot of damage to the planet.

BUT, what happens to the ship? I have always ruled that you CAN do it, but if you are in an atmosphere, your ship is destroyed - roll up another character.

I allowed it in one game and then we got to thinking about the Ine Givar terrorists (or any other terrorist group). IF a suicide attacker wanted to, they could destroy just about any major starport for the cost of a crappy old ship. The 3I setting sure doesn't seem to allow that, so we decided that it wasn't possible.

Our explanation was that the Jump Bubble could not form in an atmosphere. You needed a vacuum; even a Trace atmosphere was too thick.

That DOES mean it could be used on a vacuum world, but again, within 10D you ship is destroyed and we roll up new characters. AND, in a vacuum, your jump within 10D isn't going to damage anything... so it was a wasted attempt.

Roll Critical Hits or just saying "dead", either way, there needs to be an in-game reason why everyone isn't just jumping from the surface.

Also I believe I stated my rule incorrectly about Critical Hits.

It is 1 Critical hit per 10D inside the 100D limit. At 10D, you would roll 10 Critical Hits - inside 10D, your ship emerges from Jump Space as a splash of sub-atomic particles and a small gamma-ray-burst - very pretty. Let's roll up new characters...

HOWEVER, if you follow the Marc Miller concept of Jump Shadows, then quite simply, it is impossible to jump from inside the 100D limit. PERIOD.

Your Game, Your Ruling

[Condottiere]

Like I said, make the effects incremental to the distance.

[steve98052]

Assuming that an attempt to jump within an atmosphere is possible at all -- and a ship inside an inflated gas balloon in space outside 100 diameters of any massive body might be such an instance -- it would leave a void in the atmosphere equal to the volume of the ship plus jump bubble, maybe 5% extra. The sudden disappearance of 1400 cubic meters of starship from an atmosphere would be a momentary void in the atmosphere, which would immediately collapse inward at a speed determined by the average thermal velocity of the atmosphere -- around Mach 1.35 in room temperature air -- until the void filled, after which it would rebound with something resembling a thunderclap. That would not be catastrophic, though it could cause deafness, light injuries, and minor damage locally.

[Reynard]

And people on the ground report hearing the sound of 'BAMF!' and the lingering smell of sulphur.