>
> On 28Jun2020 1525, Thomas Jones-Low wrote:
>>
>> The other thing to keep in mind is developing the Jump Drive is a
>> difficult challenge. It’s only been done seven times in in the
>> history of Charted Space. Based on the outcomes of the misjumps and a
>> few other statements, the process of entering jump space is an
>> unstable, chaotic one. You, the Astrogator and the computer system
>> you are using need to know a number of factors to a high degree
>> accuracy.
> The jump drive, as it was originally described, was a quite reliable
> piece of kit. You could only misjump using the original '77 rules if
> you jumped too close to a world or star (and the star part is
> explicit), were using unrefined fuel, or your drive was past due for
> maintenance. The chance was 12+, -1 if using refined fuel (i.e. no
> chance at all) if you did things right.
>
> The '81 version changes things somewhat - using unrefined fuel is
> perfectly safe in a scout of military ship, stars are no longer
> mentioned as causing problems, there's an extra DM for being within 10
> diameters of a world (in case within 100 diameters wasn't scary
> enough), lack of drive maintenence doesn't make misjumps more likely,
> and a bad enough roll can destroy a ship rather than just cause a
> misjump.
>
>
> In both versions, given the size of the computers required for jumps,
> especially long ones, it seems that finding a 'course' that gets you
> where you want to go is hard, but without it it seems that actually
> you just go nowhere.
>
> In MegaTraveller there are a series of tasks required before you can
> jump, but the same rules applies - if you play it safe there's no
> chance of a misjump.
>
> In TNE the same applies, but there's also a Piloting roll upon
> emergence, and a poor roll on that means emerging with an inconvenient
> vector.
>
> T4, I'm not sure of the way it's expressed, but I think it's like the
> original '77 rules, but without the bonus for refined fuel. If so,
> this is the first set of rules that gives a chance of a misjump when
> you're doing everything right.
>
> GURPS Traveller allows a small chance of something going wrong on a
> jump even if you play it safe, and there's some chance this will be a
> misjump, but they should be very rare unless the ship's engineer has a
> low skill level.
>
> T20 is less than clear (I assume the DC21 check for misjump is a typo,
> because otherwise it's automatic), but seems to imply that with a
> low-skill astrogator it'll be fairly common, but most misjumps just
> damage machinery or mess with the occupants - about 1in20 are 'go who
> knows where' events, and 1in10 are 'game over'.
>
> MgT requires an engineering check, modified for bad fuel, etc., which
> means that a skill engineer can safely jump when common wisdom says
> you really shouldn't (something that's also a thing in MT, TNE, and GT).
>
> I don't know T5 well enough to be sure of the odds of misjumps, and
> don't have access to other Hero Traveller.
>
> Overall, the newer the rule system, the worse your odds, it seems.
>
GT: Far Trader (IIRC) actually addressed this - modulo GM shenanigans,
El Capitane succeeding on a Shipmaster +2 (or +3) roll means that
particular jump was routine - ie, all paperwork in order, no need to
roll for jump, etc etc etc, crush the lesser races, unlimited rice
pudding for all.
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