Whoa whoa whoa- 1000D limit?

[kilemall]

Went perusing through the FFE document links and read through the forms PDF for T5.

Clearly very good stuff, with highly flexible gun and vehicle builds, a possibly interesting starship build system, and lovely alien mechanics.

DNA feed into characters? Wow.

Been using my own homebuilt for knowledge type skills, skill sets are neat, so all looking good, as one would expect coming up on 4 decades of Traveller dev.

However, the big shock was the 1000D limit for M drive.

Years ago I was already using a 10D like limit for grav, so I am onboard with that.

But I have a whole lotta sublight and Oort cloud action going on, just a single solar system is a Big Verse, and so I am highly likely to utterly ignore that rule.

However, I would be interested to know what the backstory reasoning is (beyond game design of forcing players to 'interesting places'). Maybe there is something in the tech description that makes this concept palatable or even desirable.

 

[SanDragon]

That's the range that the drive operates most efficiently.

The grav drive is with 10 diameters, then it drops off.

The maneuver drive is efficient within 1000 diameters of an object that has gravity to push against.

 

[whulorigan]

However, the big shock was the 1000D limit for M drive.

Years ago I was already using a 10D like limit for grav, so I am onboard with that.

But I have a whole lotta sublight and Oort cloud action going on, just a single solar system is a Big Verse, and so I am highly likely to utterly ignore that rule.

However, I would be interested to know what the backstory reasoning is (beyond game design of forcing players to 'interesting places'). Maybe there is something in the tech description that makes this concept palatable or even desirable.

The limit is probably a nod to the fact that otherwise any ship owned by anybody can become a potential relativistic kinetic-kill planet-buster if it can accelerate without limit. The 1000D limit had already been established for M-Drives in T4 as well.

Note that the M-Drive can still be used past 1000D, just at 1.0% efficiency. Beyond that, it is probably reasonable to install something like a HEPlaR Drive, at least as a secondary maneuvering drive in addition to the M-Drive. Alternatively, you could perhaps use an N-Drive (NAFAL).

Note also that the "Thruster" in T5.09 is a Drive that can accelerate independent of G-Fields. It is styled as a "Dean-Drive", but if that seems a little too pseudo-science, you can always just use the rule-mechanics for the Thruster and replace the handwavium with something similar to MT/DGPs Strong Nuclear Force based Reactionless-Thruster.

 

[kilemall]

That's the range that the drive operates most efficiently.

The grav drive is with 10 diameters, then it drops off.

The maneuver drive is efficient within 1000 diameters of an object that has gravity to push against.

So maneuver drive is some super space-gravitic drive?

You crazy kids and your new editions!

 

[Spartan159]

A thought that occurs to me is that going from a smaller planet to a larger one is no real problem, just coast between 1000 diameters, but going from a larger to a smaller you need to be careful not to over accelerate as you will have a shorter deceleration distance. Not sure I'm thrilled with the 1000 diameter thing either.

 

[robject]

A thought that occurs to me is that going from a smaller planet to a larger one is no real problem, just coast between 1000 diameters, but going from a larger to a smaller you need to be careful not to over accelerate as you will have a shorter deceleration distance. Not sure I'm thrilled with the 1000 diameter thing either.

Very good observation. Be careful when slinging from Saturn to Pluto. Unless your chord dips inside the 1000D limit, in which case you're good.

By the way, 1000D from Jupiter is 1 AU...

Usually the 1000D limit doesn't matter. When you're travelling that distance, you usually jump to your destination. Even 80 AU at 6G is 10 days. So it changes the edge effects.

And of course MOARN -- map only as really necessary -- in other words, if it won't contribute to a particular game session, don't use it. That rule ALWAYS applies to EVERYTHING.

There's also NAFAL now, which could supplement the M-drive for canon cases (e.g. the Islands Cluster colony ships, the Loeskalth planetoid, Chamax sleeper ships) and things like insystem Deep Space barges.

 

[pendragonman]

Then remember just how much delta-v you build up, even at 1 g, accelerating at a constant rate to the 1000d limit.

Provided my arithmetic is correct...

Take a size 7 planet. ~11,200 km for a diameter. So ~11,200,000 km until loss of maneuver efficiency. Or ~11,200,000,000 meters. At 1 g you accelerate at 10 meter per second squared. Or about 33,466 seconds of acceleration. So at the end you are cruising at ~334,660 meters per second. Or ~335 km per second.

1 AU is ~149,597,871 km. takes a bit more than 124 hours to travel, or a bit more than five days.

Of course, then you gotta stop...


The point is, the Oort Cloud is ~5000-10,000 AU. You were probably already using jump to get there if you have it. If not, well, this limit is not going to elongate your trip by that much. You are still cruising the system like the early age of sail.

 

[kilemall]

The limit is probably a nod to the fact that otherwise any ship owned by anybody can become a potential relativistic kinetic-kill planet-buster if it can accelerate without limit. The 1000D limit had already been established for M-Drives in T4 as well.

I'm a simple caveman coming out of my CT/2300 low berth after a sleep of 30 years, I have no idea what T4 or any of the others are.

That fuel-based version I'm reading about is practically a redo of Triplanetary movement. But even Triplanetary had torch drives.

Note that the M-Drive can still be used past 1000D, just at 1.0% efficiency. Beyond that, it is probably reasonable to install something like a HEPlaR Drive, at least as a secondary maneuvering drive in addition to the M-Drive. Alternatively, you could perhaps use an N-Drive (NAFAL).

Caveman. Simple. No intervening edition knowledge.

Okay, read up on a summation here on drives, accurate?

http://forums.sjgames.com/showthread.php?t=93906

And NAFAL is a general term for what I guess would be an unusual near-C deep space drive option.

Having two maneuver drive types mounted on the same ship just smacks very hard of sail-and-steamships, three is just an Einstein-Rosen bridge too far for me.

I can sort of get into the intense microgravitic field generating thrust in some of the articles I'm reading, it's like being pushed by an internal Alcuberrie drive, but stutterwarp seems cleaner then all of this.

Note also that the "Thruster" in T5.09 is a Drive that can accelerate independent of G-Fields. It is styled as a "Dean-Drive", but if that seems a little too pseudo-science, you can always just use the rule-mechanics for the Thruster and replace the handwavium with something similar to MT/DGPs Strong Nuclear Force based Reactionless-Thruster.

Hmmm, I'm still sticking with my IMTU mix for now, not feeling it for these options.

 

[kilemall]

Then remember just how much delta-v you build up, even at 1 g, accelerating at a constant rate to the 1000d limit.

Provided my arithmetic is correct...

Take a size 7 planet. ~11,200 km for a diameter. So ~11,200,000 km until loss of maneuver efficiency. Or ~11,200,000,000 meters. At 1 g you accelerate at 10 meter per second squared. Or about 33,466 seconds of acceleration. So at the end you are cruising at ~334,660 meters per second. Or ~335 km per second.

1 AU is ~149,597,871 km. takes a bit more than 124 hours to travel, or a bit more than five days.

Of course, then you gotta stop...


The point is, the Oort Cloud is ~5000-10,000 AU. You were probably already using jump to get there if you have it. If not, well, this limit is not going to elongate your trip by that much. You are still cruising the system like the early age of sail.

Oh sure, I'm jumping out there, but somebody had to get out there in the first place to map all the smidgeny bits of grav field generated by the larger objects so you can get to oasis of maneuver.

There is going to be huge chunks of space in-between maneuver oasis, and what the heck do misjumped out in the middle of nowhere ships do to get home?

Finally, I guess it just feels like cramping my space style. Not necessarily logical, just feels that way.

 

[Spartan159]

Finally, I guess it just feels like cramping my space style. Not necessarily logical, just feels that way.

Just had an image of Cat from Red Dwarf saying that pop into my head. :rofl:

 

[mike wightman]

I for one will never adopt the T5 normal space drives. That would require the retconning of my favourite bit of The Traveller Adventure - the trade war scenario where you ambush ships in an empty hex - no objects for the T5 drive to work so no scenario.

 

[pendragonman]

I for one will never adopt the T5 normal space drives. That would require the retconning of my favourite bit of The Traveller Adventure - the trade war scenario where you ambush ships in an empty hex - no objects for the T5 drive to work so no scenario.

planemos...

 

[Magnus von Thornwood]

Responses.

/snips/

There is going to be huge chunks of space in-between maneuver oasis, and what the heck do misjumped out in the middle of nowhere ships do to get home?

/more snips/

They die of course. Space travel is dangerous like that.

I for one will never adopt the T5 normal space drives. That would require the retconning of my favourite bit of The Traveller Adventure - the trade war scenario where you ambush ships in an empty hex - no objects for the T5 drive to work so no scenario.

T5 allows for empty hex move, it just means packing reaction drives, not just gravitic ones.

 

[aramis]

The 1000D limit is NOT new to T5. It was introduced in T4.

 

[GypsyComet]

The 1000D limit is NOT new to T5. It was introduced in T4.

Hmm. I thought it was earlier than that.

 

[aramis]

Hmm. I thought it was earlier than that.

Fans were arguing for it on the TML in 1994-95, IIRC, but it wasn't canon until T4.

 

[kilemall]

They die of course. Space travel is dangerous like that.

Fie on killer gravitic drive! If Ripley can make it back low berthing on a reaction drive gig, good enough for me!

 

[mike wightman]

T5 allows for empty hex move, it just means packing reaction drives, not just gravitic ones.

Oh I know all about the work arounds.

But that means re-designing the standard subsidised merchant with a reaction drive.

 

[mike wightman]

Fans were arguing for it on the TML in 1994-95, IIRC, but it wasn't canon until T4.

IIRC the first time the idea was in print was a DGP Q&A in either a Traveller's Digest of a MTJournal. Have to go check the loft...

 

[aramis]

IIRC the first time the idea was in print was a DGP Q&A in either a Traveller's Digest of a MTJournal. Have to go check the loft...

MT errata has early "antigravity maneuver drives" limited after 10 diameters. The 1000D limit isn't in the consolidated errata. And doesn't become canon as far as I can tell until T4, with FF&S2 making all gravitic thrusters fall off after 1000D - note that in both MT and T4, it wasn't to 0-thrust, either.