Time to accelerate to 1% c at 1G

[zero]

The only reason to limit speeds when travelling would be if you have a Reaction Drive and want to save fuel :?

 

[GypsyComet]

Pilots don't plot courses through dangerous zones any more than you would aim for the guard rail while driving on the freeway.

At these accelerations travel is basically straight line. Those long arcing curves you see in NASA animations are fuel efficient limited-burn bumpercar rides between gravity wells that take months or years. By comparison, at even 1g constant you are literally pointing the nose at Saturn and hitting "GO!" Minimum time transfers have few options, and if you are vectoring around an obstacle you ARE adding time to the trip.

Space is a LOT bigger than you imagine.

:roll:

 

[rust]

By comparison, at even 1g constant you are literally pointing the nose at Saturn and hitting "GO!"

Not really, Saturn has an orbital speed of 9.69 km per second, and at 1 G
you would need about a week to travel from Earth to Saturn, so Saturn
would have moved quite a distance since you pointed the nose at it and
hit "GO!" - you would miss it by more than 5 million kilometers.

Since all planets in a system are constantly moving, the "straight line"
flight paths between them are constantly moving, too. Therefore ships
starting a few hours before or after your ship will use a different flight
path, and as a result there are no permanent "routes" between planets,
the ships do not travel on the same "highway", they are distributed over
a huge volume of interplanetary space - no traffic jams there.

So, if there really is any kind of obstacle or other problem on your inten-
ded flight path, just start a little earlier or later, and it will be gone. 8)

 

[DFW]

At these accelerations travel is basically straight line. Those long arcing curves you see in NASA animations are fuel efficient limited-burn bumpercar rides between gravity wells that take months or years.

Nope. The planets are in motion relative to each other and, your ship.

:roll:

Rolling your eyes doesn't change facts. I'm sorry. For example. If the solar system was 1 KM in diameter, the Sun would be ~1/10 of a millimeter in diameter. Jupiter would be ~1/100 of a millimeter. A 100 meter long ship is 140000 times smaller than Jupiter.

Hitting something on accident, while travelling between planets (without sensors) would be like winning the lottery. Hitting something by accident WITH sensors, pretty much an impossibility.

Even hitting something on purpose is a challenge.

 

[Rick]

By comparison, at even 1g constant you are literally pointing the nose at Saturn and hitting "GO!"

Not really, Saturn has an orbital speed of 9.69 km per second, and at 1 G
you would need about a week to travel from Earth to Saturn, so Saturn
would have moved quite a distance since you pointed the nose at it and
hit "GO!" - you would miss it by more than 5 million kilometers.

Since all planets in a system are constantly moving, the "straight line"
flight paths between them are constantly moving, too. Therefore ships
starting a few hours before or after your ship will use a different flight
path, and as a result there are no permanent "routes" between planets,
the ships do not travel on the same "highway", they are distributed over
a huge volume of interplanetary space - no traffic jams there.

So, if there really is any kind of obstacle or other problem on your inten-
ded flight path, just start a little earlier or later, and it will be gone. 8)

Not to mention that if you've just taken off from a planet, you'll already be moving at that planets speed and in the direction of it's orbit before you even clear atmosphere anyway - that's where navigator's really earn their biscuits!

 

[GypsyComet]

Rolling your eyes doesn't change facts.

Your opinion, on the other hand, is insulting.

Even hitting something on purpose is a challenge.

Not with the accelerations available casually in Traveller.

Saturn has an orbital speed of 9.69 km per second, and at 1 G
you would need about a week to travel from Earth to Saturn, so Saturn
would have moved quite a distance since you pointed the nose at it and
hit "GO!" - you would miss it by more than 5 million kilometers.

Iapetus orbits at 3.5 million km from Saturn, and Saturn's Jump Horizon is at 10-12 million km. Five Mkm off is not really a miss in Traveller terms. A 1g ship is up to Saturn's orbital velocity from flat in about 15 minutes, and if the pilot is worth his pay that was done during the last few hours of deceleration. The curve in your total flight path amounts to pulling into the right lane after driving arrow straight for two hundred miles.

 

[GJD]

Whilst interesting and entertaining, these discussions on orbital mechanics aren't really relevant to the original poster.

The significance of the 1% of the speed of light was that this was the required velocity for the FTL drive to activate in the original Star Frontiers. Travelling between planets was largely ignored beyond the transit time to reach, and decellerate from, 1% of c at the start and end of each trip.

Personally, I always thought it was a rubbish concept - in the original game ships spontaneously entered FTL when they reached .01c, no special star drive required - just lots of thrust. I always wondered why things already travelling at .01c didn't trip in and out of FTL, or what happened if you accelerated to .02c?

I quickly ditched it and added a different jump drive.

G.

 

[DFW]

Your opinion, on the other hand, is insulting.

I'm sorry. I've posted facts that show conclusively, that it is nigh impossible to accidentally run into something. If you can't counter with facts, well, there is nothing I can do to remedy that deficiency on your part.

 

[barnest2]

I'm sorry. I've posted facts that show conclusively, that it is nigh impossible to accidentally run into something. If you can't counter with facts, well, there is nothing I can do to remedy that deficiency on your part.

This is the thing. Two ships launching even a few minutes apart aiming at the same target will have quite different vectors, due to the speeds involved. So there is no chance of two things hitting each other, particularly since they can all see each other.

 

[DFW]

This is the thing. Two ships launching even a few minutes apart aiming at the same target will have quite different vectors, due to the speeds involved. So there is no chance of two things hitting each other, particularly since they can all see each other.

Exactly correct.

 

[BP]

Yeah - space is huge and mostly empty - and chances of unanticipated collisions are so remote as be less than winning most (if not all) lotteries.

However, someone usually wins a lottery eventually. Just like getting struck by lightning, hit by a meteorite, or run into by a deer. Planning for such eventualities is a good idea, expecting them to happen is another thing.

In all these cases, as with space travel, one can generally do things that impact (pun) their odds. Buy more tickets, golf in thunderstorms, move to Jupiter, speed down country roads at dusk. In space, one can try closer to gravity wells and whipping thru orbital rings (sorry, asteroid belts and such are generally just too spartan).

Safety is a relative thing. Space travel is inherently dangerous. Most impacts are gonna do damage - regardless of how fast your ship is going (especially as that has no bearing (pun) on the speed of what hits you). Going faster reduces your time in the danger zone - though it does have an impact (hehe) on vectoring. Not that it matters enough in general to make a difference, either way.

In America we have legal speed limits on our roads (posted or implied - varying by state, municipality and whim). In theory, this is for safety. However, people are injured and die everyday at these speeds and federal 'safety' tests don't test vehicles at anywhere near most of the legal limits.

In some states, the speed limits are treated legally as 'suggested safe limits' - i.e. if it was reasonably considered as safe at 120 mph as the posted limit, at the time and conditions of a ticket, the ticket has a good chance of being dismissed. In other states, however, the speed limit is an 'absolute limit' - its the law, safe or not and thus less likely to be dismissed (at least on safety grounds - being respectful to Troopers and Judges can work though ).

So, one good (only one I can see really) reason for 'speed limits' on in-system travel... so the law can catch you!

• 
  Sorry, sir, the in-system warnings are quite clear and being broadcast on all standard frequencies - there is an orbital penal colony under construction not 50,000 klicks from here - and you were also accelerating in an educational moon zone...
  
  That's triple fines and I'm gonna need you to pull over into a higher orbit and power down your maneuver drive...

 

[GypsyComet]

So, one good (only one I can see really) reason for 'speed limits' on in-system travel... so the law can catch you!

Or Search and Rescue. If something does happen (and in-system travel is where the pirates are going to be most common, as one example) your hulk isn't already past Pluto by the time the (likely rather sparse) SDBs figure out you are in trouble. A couple percent of c will have you out of the system in a remarkably short time, really.

 

[DFW]

Or Search and Rescue. If something does happen (and in-system travel is where the pirates are going to be most common, as one example) your hulk isn't already past Pluto by the time the (likely rather sparse) SDBs figure out you are in trouble. A couple percent of c will have you out of the system in a remarkably short time, really.

With actual Trav rules of in system travel. Pirates will ONLY be engaging ships at beginning or end of interplanetary trips. At mid point, the speeds are too great to engage a ship. Unless, you have been pacing them or a day or two...

 

[GypsyComet]

Or had a plant on-board. "Piracy" covers a lot of activities. That's probably appropriate to a new Topic, though.

 

[DFW]

Or had a plant on-board. "Piracy" covers a lot of activities. That's probably appropriate to a new Topic, though.

Right. Not really relevant to the topic. But, sounds like an intersting topic to discuss.

 

[rust]

Or Search and Rescue. If something does happen (and in-system travel is where the pirates are going to be most common, as one example) your hulk isn't already past Pluto by the time the (likely rather sparse) SDBs figure out you are in trouble. A couple percent of c will have you out of the system in a remarkably short time, really.

A very good point, perhaps less so because of pirates and more because
of all the other things which can go wrong with and on a ship.

 

[BP]

Yeah - that is another good reason. So they can fine.. er.. bill you or your heirs for the recovery, tow and storage... :lol:

• Mr. Jamison. The impound on your vessel, what's left of it at any rate, is indeed justifiable and I would recommend you temper your tone when addressing this court and its wisdom.
  
  Besides the long overdue payment of fees to partially defray the generous assistance of the Buloxia Guard Service and expenses both civilian and statutory of the Buloxia system, it has also come to our attention that there is also the issue of fines outstanding to the Fynyalots system for speeds exceeding their in-system guard safety limits, in addition to possible fines imposable for excessive acceleration through Orbit Complex L3 and reckless endangerment regards unauthorized maneuvers in prohibited regions adjacent to the Asteroid Resource Recovery Operations Delta IV.
  
  Let me make you aware of the terms of the Lotabool-Buloxia-Fynyalots Cooperative Collections Enforcement act of 1103...

 

[DFW]

A very good point, perhaps less so because of pirates and more because
of all the other things which can go wrong with and on a ship.

Not really. MTBF for major systems on a maintained star ship are ridiculously high.

 

[BP]

Yeah - but then there are Player ships! :lol:

 

[DFW]

Yeah - but then there are Player ships! :lol:

MTBF = every time GM feels sadistic. :lol: