If you haven't already checked out Erin Palette's post on how Maneuver and Jump Drives work in Traveller, take a moment to do so. It's really good stuff. Plus, it's Erin Palette actually talking about gaming and how often does that happen? ;)
I kid, I kid, I am the kidder.
Now, I have nothing so cool as an intelligent and well thought out scientific essay on the technobabble of our mutual favorite Sci-Fi RPG (or at least one of them). Instead, I have a cool illustration of the alien Za'Tachk, another member of the Hive Federation...
And a cool chart showing how 'fast' Traveller's Jump Drive goes IMTU. See, in the Traveller Universe I have been using for the last 20+ years or so, Jump Drive is slightly different than the way it has been traditionally presented in canon.
Generally, when a starship enters Jump Space, it is there for a week. So, a Jump-1 vessel goes 1 parsec in 1 week. Likewise, a Jump-6 vessel (the most powerful and effective Jump Drive there is) goes 6 parsecs in 1 week. Now, how long would it take a Jump-6 vessel to go 1 parsec.
Simple. 1 week. It takes 1 week to go from Normal Space to Jump Space and back. It always takes 1 week.
That did not sit well with my collection of Star Trek, Star Wars and related Sci-Fi IP buddies, so we have an alternate breakdown of how long a starship is in Jump Space and how long it takes to travel a given distance. Like so...
So the skinny here is that as drives improve in power they are also more efficient to some degree. Regardless however, the key is always that it takes 1 week to go the number of parsecs equal to the drive designation. Also, if you have a Jump-5 Drive it should take you two week (2 x The Drive Designation) to go 10 parsecs. A Jump-2 vessel will take two weeks to go 4 parsecs, etc.
The change doesn't have a major effect on the game except that the character's don't age as quickly just getting from place to place. Also, it does (somewhat) encourage a bit more traveling in Traveller, which I am all for, but I am aware not every Traveller GM enjoys. Many prefer that their PC crews hang out in one place for a while. Not me. Part of the reason for this chart is that I want to play Traveller not Settler.