Whoa whoa whoa- 1000D limit?

[Hyphen]

FWIW, T4 Fire, Fusion & Steel says that the drop-off comes at 2000 AU from a normal, Sol-like star.

 

[whulorigan]

FWIW, T4 Fire, Fusion & Steel says that the drop-off comes at 2000 AU from a normal, Sol-like star.

I cant find that reference in T4:FF&S. Do you have a page number?

In T4: Starships it says:

T4: Starships, p.71:

Thruster Plates (Tech Level 12+)
Another effect of the tech level 12 mastery of gravitics (the science of gravity) is the invention of thruster plates. Earlier contragrav technology only negates the effects of a gravitational field: thruster plates actually use the field itself for propulsion, by ‘grabbing on’ to the curvature of space and running along it much like an ant on the slope of a sugar-bowl. Rather than wasting valuable mass by hurling it out the rear of the ship, as lower-tech rockets do, gravity drives use the stellar system itself as their reaction mass (much as a train pushes against its track, and the planet below, rather than by expelling exhaust). A small change in a star’s momentum translates to a huge velocity change for the much smaller spacecraft.

Unlike the ant of the earlier example, however, the slope of the “bowl” has a different effect on gravitic-drive ships. They depend on the slope for propulsion. Beyond a certain point, quantum-gravitic effects drastically reduce the efficiency of a gravitic drive ship by a factor of a hundred or more, and thus they cannot maneuver effectively in deep-space unless they have an auxiliary drive, though they can remain there while, for example, computing jump parameters. The cutoff parameter turns out to be around 2,000 solar radii. Beyond this point, thruster plates are virtually worthless for anything beyond stationkeeping, and some alternate form of propulsion is needed. Thus, the Drenid Deep Space Research Facility in Sylea system is still resupplied using an automated freighter driven by a fusion rocket.

Another disadvantage of thruster plates is their gravitic and visual signature: gravity-wave sensors can easily detect the peculiar emissions characteristic of the system. Normal telescopic sensors are approximately as useful: the ‘thruster plates’ themselves give off exotic particles, which very quickly decay as they leave the thruster field. The bright blue glow emanating from the rear of many new Imperial vessel is, perhaps, more distinctive than the subtle space-warp.

2000 solar radii is 1000 solar diameters.

 

[aramis]

Wayne, the most important thing to understand about that quote is that it shows T4 Starships wasn't written by people who had done the math fully...

A station-keeping drive is (typically) around 0.01G for sats... it's also about 10x the G-rating that the fastest moving space probe ever sent from real-world Earth to date has had: The DS-1 probe. If it provides any continuous thrust, it's capable of quite powerful vector buildup.

Also, the T4 FF&S2 page reference (which quotes exactly like T4 starships), is page 85, right column.

 

[whulorigan]

Also, the T4 FF&S2 page reference (which quotes exactly like T4 starships), is page 85, right column.

You and Hyphen are right. FF&S2, p.65 does say 2000AU for the "cut-off" instead of 2000 radii.

Wayne, the most important thing to understand about that quote is that it shows T4 Starships wasn't written by people who had done the math fully...

A station-keeping drive is (typically) around 0.01G for sats... it's also about 10x the G-rating that the fastest moving space probe ever sent from real-world Earth to date has had: The DS-1 probe. If it provides any continuous thrust, it's capable of quite powerful vector buildup.

Oh agreed. I am not arguing that the Thruster wouldn't be useful even past the "cut-off". I was just pointing out that T4 & T5 both noted the same limitation of 1000 diameters. The FF&S2 quote, however, is an interesting anomaly. I take it that one or the other is a T4 erratum.

 

[aramis]

You and Hyphen are right. FF&S2, p.65 does say 2000AU for the "cut-off" instead of 2000 radii.

Oh agreed. I am not arguing that the Thruster wouldn't be useful even past the "cut-off". I was just pointing out that T4 & T5 both noted the same limitation of 1000 diameters. The FF&S2 quote, however, is an interesting anomaly. I take it that one or the other is a T4 erratum.

Check to see if it's in the T4 errata... if not, add it to the errata thread.