Short fast jumps, long slow jumps, and the 7.0 LY limit
Posted: Mon Dec 17, 2012 5:16 am
One interesting thing I've noticed with the Advanced Navigational Array is that it frequently seems like the shortest route with fewest witchspace jumps between two systems over (say) 12.0 LY apart is also the slowest - and the longer route with more jumps is the fastest. Which is counter-intuitive, especially as due to the 7.0 LY limitation on witchspace jumps your ship is typically forced to spend a significant amount of time in normal space travelling to a convenient refuelling point (a station, fuel satellite, or the local star to sun-skim with your fuel scoops), so in theory more frequent jumping / refuelling would incur a greater time penalty than less frequent jumping. After all, here on Earth the flight-times for transoceanic airliners with refuelling stops are greater than those which can fly non-stop, and this is why commercial aircraft have been built with sufficient range to fly (say) Auckland to Los Angeles non-stop instead of having to refuel en route in Apia and Honolulu.
So if the Advanced Navigational Array calculations are correct, this anomaly exposes a significant property of travelling through witchspace... which may also explain (in-game) the 7.0 LY witchspace jump limit and why no Oolite ship carries more than 7.0 LY worth of Quirium in standard tankage.
One possible explanation is that the greater the length of the jump, the longer it takes to pass through the tail end of a witchspace wormhole compared to a shorter jump, possibly due to the amount of "kick" into witchspace that a ship gets when entering the wormhole. At the start of the wormhole entry the ship is travelling quite fast, but due to (handwave) wormhole physics the ship starts to slow down... and the longer the wormhole is, the slower - relatively speaking - the ship is travelling though the tail end before it exits. This means that short jumps would result in an overall faster transit time through the witchspace wormhole as the ship would be moving relatively faster in the last half of a short jump as opposed to a long one.
The 7.0 LY limit can also be explained in the same way. It is possible that the wormhole tail slow-down effect for a ship dramatically increases past the 4.0-5.0 LY point, so that if a jump of 7.5 LY or over was attempted the ship would have lost sufficient speed so that it never leaves the wormhole (and is either stuck in hyperspace or between dimensions). Therefore, 7.0 LY is the maximum "safe" limit for a standard witchspace jump. In-system refuelling methods such as sun-skimming, fuel stations and GalSec stations means that there is little incentive to install additional fuel capacity at the expense of cargo or weapon loads other than for the truly dedicated, and commercial imperatives of "not building capacity that will never be used" means that no shipbuilders in the Oolite universe have any incentive for constructing ships with standard fuel tanks that will carry more than 7.0 LY worth of Quirium. Galactic hyperdrives are not subject to this wormhole effect as (handwave) different principles are used in galactic wormhole generation as opposed to "standard" witchspace drives.
The only problem with the this theory for the 7.0 LY limitation is that the safety limit could be controlled by the witchspace navigation computer without the need to artificially limit the size of fuel tanks, leaving a ship to perform multiple < 7.0 LY short jumps on a single 20.0 LY capacity tank without frequent refuelling or risking getting lost in witchspace. Given that there's tankers carrying large quantities of Quirium about the Ooniverse, and we've established in the "Tankers" thread that tankers don't regularly go "BOOM!" just because they're hauling bulk Quirium, a 20.0 LY capacity fuel tank isn't inherently impossible or unsafe from a technical perspective.
It's possible of course that the 7.0 LY fuel tank limit is regulatory in nature, rather than technical. Maybe GalSec classes every ship with Quirium tanks greater than 7.0 LY capacity as "Tankers", and taxes them to the point where 7.1+ LY capacity fuel tanks are just not in demand outside of Quirium haulage companies...
So if the Advanced Navigational Array calculations are correct, this anomaly exposes a significant property of travelling through witchspace... which may also explain (in-game) the 7.0 LY witchspace jump limit and why no Oolite ship carries more than 7.0 LY worth of Quirium in standard tankage.
One possible explanation is that the greater the length of the jump, the longer it takes to pass through the tail end of a witchspace wormhole compared to a shorter jump, possibly due to the amount of "kick" into witchspace that a ship gets when entering the wormhole. At the start of the wormhole entry the ship is travelling quite fast, but due to (handwave) wormhole physics the ship starts to slow down... and the longer the wormhole is, the slower - relatively speaking - the ship is travelling though the tail end before it exits. This means that short jumps would result in an overall faster transit time through the witchspace wormhole as the ship would be moving relatively faster in the last half of a short jump as opposed to a long one.
The 7.0 LY limit can also be explained in the same way. It is possible that the wormhole tail slow-down effect for a ship dramatically increases past the 4.0-5.0 LY point, so that if a jump of 7.5 LY or over was attempted the ship would have lost sufficient speed so that it never leaves the wormhole (and is either stuck in hyperspace or between dimensions). Therefore, 7.0 LY is the maximum "safe" limit for a standard witchspace jump. In-system refuelling methods such as sun-skimming, fuel stations and GalSec stations means that there is little incentive to install additional fuel capacity at the expense of cargo or weapon loads other than for the truly dedicated, and commercial imperatives of "not building capacity that will never be used" means that no shipbuilders in the Oolite universe have any incentive for constructing ships with standard fuel tanks that will carry more than 7.0 LY worth of Quirium. Galactic hyperdrives are not subject to this wormhole effect as (handwave) different principles are used in galactic wormhole generation as opposed to "standard" witchspace drives.
The only problem with the this theory for the 7.0 LY limitation is that the safety limit could be controlled by the witchspace navigation computer without the need to artificially limit the size of fuel tanks, leaving a ship to perform multiple < 7.0 LY short jumps on a single 20.0 LY capacity tank without frequent refuelling or risking getting lost in witchspace. Given that there's tankers carrying large quantities of Quirium about the Ooniverse, and we've established in the "Tankers" thread that tankers don't regularly go "BOOM!" just because they're hauling bulk Quirium, a 20.0 LY capacity fuel tank isn't inherently impossible or unsafe from a technical perspective.
It's possible of course that the 7.0 LY fuel tank limit is regulatory in nature, rather than technical. Maybe GalSec classes every ship with Quirium tanks greater than 7.0 LY capacity as "Tankers", and taxes them to the point where 7.1+ LY capacity fuel tanks are just not in demand outside of Quirium haulage companies...