Rules Only: Interplanetary Travel (distance, acceleration, time)

[Spinward Flow]

One Way Nonstop Interplanetary Travel

D=AT²/4

D = Distance in meters (1 km = 1000 m)
A = Acceleration (1G = 10 meters / second²)
T = Seconds (12 hours = 43,200 seconds)

1 AU = 149,600,000 km = orbital distance between Sol and Terra

	1G​	2G​	3G​	4G​	5G​	6G​
12 hours (0.5d)	4,665,600 km (0.031 AU)	9,331,200 km (0.062 AU)	13,996,800 km (0.093 AU)	18,662,400 km (0.124 AU)	23,328,000 km (0.156 AU)	27,993,600 km (0.187 AU)
24 hours (1.0d)	18,662,400 km (0.124 AU)	37,324,800 km (0.249 AU)	55,987,200 km (0.374 AU)	74,649,600 km (0.499 AU)	93,312,000 km (0.623 AU)	111,974,400 km (0.748 AU)
36 hours (1.5d)	41,990,400 km (0.280 AU)	83,980,800 km (0.561 AU)	125,971,200 km (0.842 AU)	167,961,600 km (1.122 AU)	209,952,000 km (1.403 AU)	251,942,400 km (1.684 AU)
48 hours (2.0d)	74,649,600 km (0.499 AU)	149,299,200 km (0.998 AU)	223,948,800 km (1.496 AU)	298,598,400 km (1.996 AU)	373,248,000 km (2.495 AU)	447,897,600 km (2.993 AU)
60 hours (2.5d)	116,640,000 km (0.779 AU)	233,280,000 km (1.559 AU)	349,920,000 km (2.339 AU)	466,560,000 km (3.118 AU)	583,200,000 km (3.898 AU)	669,840,000 km (4.477 AU)
72 hours (3.0d)	167,961,600 km (1.122 AU)	335,923,200 km (2.245 AU)	503,884,800 km (3.368 AU)	671,846,400 km (4.491 AU)	839,808,000 km (5.613 AU)	1,007,769,600 km (6.736 AU)
84 hours (3.5d)	228,614,400 km (1.528 AU)	457,228,800 km (3.056 AU)	685,843,200 km (4.584 AU)	914,457,600 km (6.112 AU)	1,143,072,000 km (7.640 AU)	1,371,686,400 km (9.169 AU)
96 hours (4.0d)	298,598,400 km (1.996 AU)	597,196,800 km (3.992 AU)	895,795,200 km (5.987 AU)	1,194,393,600 km (7.984 AU)	1,492,992,000 km (9.979 AU)	1,791,590,400 km (11.975 AU)
108 hours (4.5d)	377,913,600 km (2.526 AU)	755,827,200 km (5.052 AU)	1,133,740,800 km (7.578 AU)	1,511,654,400 km (10.104 AU)	1,889,568,000 km (12.630 AU)	2,267,481,600 km (15.156 AU)
120 hours (5.0d)	466,560,000 km (3.118 AU)	933,120,000 km (6.237 AU)	1,399,680,000 km (9.356 AU)	1,866,240,000 km (12.474 AU)	2,332,800,000 km (15.593 AU)	2,799,360,000 km (18.712 AU)
132 hours (5.5d)	564,537,600 km (3.773 AU)	1,129,075,200 km (7.547 AU)	1,693,612,800 km (11.321 AU)	2,258,150,400 km (15.094 AU)	2,822,688,000 km (18.868 AU)	3,387,225,600 km (22.648 AU)
144 hours (6.0d)	671,846,400 km (4.491 AU)	1,343,692,800 km (8.982 AU)	2,015,539,200 km (13.472 AU)	2,687,385,600 km (17.963 AU)	3,359,232,000 km (22.454 AU)	4,031,078,400 km (26.945 AU)
156 hours (6.5d)	788,486,400 km (5.270 AU)	1,576,972,800 km (10.541 AU)	2,365,459,200 km (15.811 AU)	3,153,945,600 km (21.082 AU)	3,942,432,000 km (26.353 AU)	4,730,918,400 km (31.623 AU)
168 hours (7.0d)	914,457,600 km (6.112 AU)	1,828,915,200 km (12.225 AU)	2,743,372,800 km (18.338 AU)	3,657,830,400 km (24.450 AU)	4,572,288,000 km (30.563 AU)	5,486,745,600 km (36.676 AU)
180 hours (7.5d)	1,049,760,000 km (7.017 AU)	2,099,520,000 km (14.034 AU)	3,149,280,000 km (21.051 AU)	4,199,040,000 km (28.068 AU)	5,248,800,000 km (35.085 AU)	6,298,560,000 km (42.102 AU)
192 hours (8.0d)	1,194,393,600 km (7.984 AU)	2,388,787,200 km (15.967 AU)	3,583,180,800 km (23.951 AU)	4,777,574,400 km (31.935 AU)	5,971,968,000 km (39.919 AU)	7,166,361,600 km (47.903 AU)

Any jump, regardless of number, takes approximately one week (150 to 175 hours).
Ships in jump space are untouchable and cannot communicate with other ships or stations.
Although jumps are usually made at low velocities, the speed and direction which a ship held prior to jump is retained when it returns to normal space.

Because of the delicacy of jump drives, most ships perform maintenance operations on their drives after every jump.
It is possible for a ship to make another jump almost immediately (within an hour) after returning to normal space, but standard procedures call for at least a 16 hour wait to allow cursory drive checks and some recharging.

175 + 16 = 191 hours

If a starship has insufficient Maneuver drive power to reach a destination within 192 hours (8 days) it will usually be faster to use the Jump drive to get there than relying on the Maneuver drive for the trip.
Space Anomalies can affect navigation through normal and/or jump space, altering the conditions underlying this assumption.

 

[Condottiere]

This would be fuzzy territory, because given the choice, most people would try and avoid dropping down the rabbit hole unnecessarily.

You can always bring along a couple of jerrycans of hydrogen.

 

[tjoneslo]

One Way Nonstop Interplanetary Travel

If a starship has insufficient Maneuver drive power to reach a destination within 192 hours (8 days) it will usually be faster to use the Jump drive to get there than relying on the Maneuver drive for the trip.
Space Anomalies can affect navigation through normal and/or jump space, altering the conditions underlying this assumption.

The exception to this rule is if your starting point or destination is within the 100D limit of either a large planet or, more likely, a large star. Favorite example is a giant star like Antares. The habitable zone and the world that lives there, is weeks from the 100D limit of the star. And blocked by the 100D limit of the star. You can, in theory, jump out, but that carries a high risk of misjump.

 

[Condottiere]

Any substantial gravity well inbetwixt is going to be an issue.

I would suppose that with so many gravity wells so close together insystem, spacetime might be a little bit wonky, so anomalies, likely in miniature or temporary, are likely to occur.

 

[Spinward Flow]

Any substantial gravity well inbetwixt is going to be an issue.

I would suppose that with so many gravity wells so close together insystem, spacetime might be a little bit wonky, so anomalies, likely in miniature or temporary, are likely to occur.

The Navigation skill applies to both local interplanetary as well as interstellar plotting of routes, in addition to being the skill used for interpreting the results from long range sensors and detectors (LBB1.81, p21). Don't leave New Home IV without it!

 

[Condottiere]

You need astrogation for any jump, micro or otherwise.

Since the penalty is for only a single hex, to make it more interesting, these anomalies can turn up.

Also, the occasional solar flare.

 

[Grav_Moped]

You need astrogation for any jump, micro or otherwise.

Since the penalty is for only a single hex, to make it more interesting, these anomalies can turn up.

Also, the occasional solar flare.

Not in Classic, you don't. The only skill that affects misjump in LBB2 (and LBB5 by incorporation) is Engineering, and that's only a question of whether your driveroom is adequately staffed.

Mind you, this is early installment weirdness (TV Tropes); Classic requires a Navigator for ships over 200Td, but the rules as written don't actually have them do anything. Later rules sets do include Navigation/Astrogation DMs in the task chain, as you note.

 

[Condottiere]

There's always the jump tape.

 

[aramis]

There's always the jump tape.

Bk2 says cassette, not tape. Not all cassettes are loaded with tape.

Some are loaded with ammunition.
Some with circuits (tho' these have largely come to be almost exclusively called cartridges due to the popularity of the Atari 2600 and it's labeling the circuit board cassette as a cartridge).
Some with medications.

 

[Condottiere]

There's always the old difference between clip and magazine.

One's an annoying assistant, the other has pictures of naked women.

Considering the perception of computer memory size in the Seventies, I'm more inclined to think that it would be burned on a mini compact disc.

 

[whulorigan]

There's always the jump tape.

Bk2 says cassette, not tape. Not all cassettes are loaded with tape.

Some are loaded with ammunition. ...

Now there's a surprise waiting for your navigator ...

"The chandler at the starport said just pop it in the NavComp data slot, and ... "

 

[Spinward Flow]

Aramis has kindly consented to copy the OP with the acceleration chart into the Reference forum where it can be found easily (after this thread drops off the first page here in The Fleet forum). :ssb:

Reference forum link
Fleet forum link

 

[whartung]

Bk2 says cassette, not tape. Not all cassettes are loaded with tape.

Sure, but that's doesn't mean it isn't tape either.

Just having visions of the navigator with the cassette and a pencil cursing and winding things up before he shoves it in the slot.

Or rolling a 2 on the jump roll "Cursed machine ate the tape again!", pulling out the cassette, strands of tape snarling into a messy knot.

Great optics. Real adventure.

 

[Grav_Moped]

Sure, but that's doesn't mean it isn't tape either.

Just having visions of the navigator with the cassette and a pencil cursing and winding things up before he shoves it in the slot.

Or rolling a 2 on the jump roll "Cursed machine ate the tape again!", pulling out the cassette, strands of tape snarling into a messy knot.

Great optics. Real adventure.

...or it loops through and tries to jump your ship to Regina again (it's an 8-track).

 

[Condottiere]

If at first you don't succeed.

You get eight options within a certain time window and approach, in case you don't mention to get to your initial appointment.

 

[whartung]

...or it loops through and tries to jump your ship to Regina again (it's an 8-track).

Funny, I don't think I ever had the 8-track machine "eat" a tape. Maybe its the tape size that made the difference, I don't know how different the internal mechanism was.

I'm a fan of having the "Jump Cassette" becoming more and more unreliable as time passes. Not because of some implicit limiting tech of the cassette itself, but simply that Jump space is shifting enough that a bunch of settings from 2 weeks ago just aren't correct for the current environment. So, you can use an old Jump Cassette, but the older it gets, the more chance of a mis-jump.

 

[mike wightman]

My thoughts:
you can only use the jump cassette for your planned voyage - in CT terms that means you have to use it within the 'week' allotted to jump which includes the transit time to the 100D jump distance. If you don't use it within that window then you need a new cassette...

 

[Spinward Flow]

My thoughts:
you can only use the jump cassette for your planned voyage - in CT terms that means you have to use it within the 'week' allotted to jump which includes the transit time to the 100D jump distance. If you don't use it within that window then you need a new cassette...

This is the correct answer.
Jump cassettes have a "shelf life" before they expire.

 

[Grav_Moped]

This is the correct answer.
Jump cassettes have a "shelf life" before they expire.

They would also have a "do not open until SpaceXmas" date as well. If you're doing a journey of 3 jumps out, then 3 back*, the tape for the final return jump won't be precisely accurate until 10 weeks after you depart. This could be a problem if you need to turn back after the first jump...



*at the normal cadence of jumps on alternating weeks. Outbound jumps are during weeks 1, 3, and 5; return jumps are during weeks 7, 9, and 11.

 

[Condottiere]

The problem is less than the predicted orbits of interstellar objects, which they probably could figure out centuries and millenia in advance, but stuff they couldn't account for in that time frame.