Supercrusie Slingshot

bliss · Jun 23, 2014

I know the devs are planning some sort of super cruise slingshot maneuvers around stars/planets to reach far flung spots of interest in a solar system (i.e. a rich asteroid belt 100AU from the parent star). I have had a sweet idea though (although I bet I am not the first

):

Using super cruise slingshots to reach nearby star systems. I think currently it takes around 12 hours to reach a close star by normal super cruise. Supercruise slingshots could be used to massively cut down travel time. Each slingshot would increase your speed beyond current max super cruise speeds (i.e. a system with only one celestial body could get you to warp 1, a system with seven celestial bodies could get you to warp 7 etc). The main advantage over Hyper space would be fuel conservation. You would use some fuel in your reserve tank to get you to max super cruise speed and then cut power to all systems bar life support and your super cruise autopilot. The main disadvantage would be much longer travel times than Hyper space (travel time would depend on how many celestial bodies/slingshots you could make).

A travel system like this would be perfect for explorers wanting to reach the other side of the galaxy. You would have a choice:

1 - A fast Hyper space jump using lots of precious fuel with the risk of not being able to find a suitable gas giant or star to scope fuel from.

2 - A slow Supercuise Sling shot conserving precious fuel.

The GFX for this could be AMAZING

p.s - You could rip out the hyper drive on your Sidewinder to get a bit more cargo space

Shadowdancer · Jun 23, 2014

In the next step, could we then please have the maneuver planner from KSP to actually hit the target?

Dynamo · Jun 23, 2014

Shadowdancer said:
In the next step, could we then please have the maneuver planner from KSP to actually hit the target?

That would be amazing, ED with KSP *physics*, full newtonian etc.

However imagine the upset that would cause on here, people already think docking is too hard!

Shepard · Jun 23, 2014

Dynamo said:
That would be amazing, ED with KSP *physics*, full newtonian etc.

However imagine the upset that would cause on here, people already think docking is too hard!

Why don't you disable flight assist and try?

Macca · Jun 23, 2014

Hmmm....that eould be something. Especially since we have, I think, the basic mechanics mass-and-gravity wise. Look how your speed changes in vicinity of celestial bodies.

Pyros · Jun 23, 2014

bliss said:
I know the devs are planning some sort of super cruise slingshot maneuvers around stars/planets to reach far flung spots of interest in a solar system (i.e. a rich asteroid belt 100AU from the parent star). I have had a sweet idea though (although I bet I am not the first ):

Using super cruise slingshots to reach nearby star systems. I think currently it takes around 12 hours to reach a close star by normal super cruise. Supercruise slingshots could be used to massively cut down travel time. Each slingshot would increase your speed beyond current max super cruise speeds (i.e. a system with only one celestial body could get you to warp 1, a system with seven celestial bodies could get you to warp 7 etc). The main advantage over Hyper space would be fuel conservation. You would use some fuel in your reserve tank to get you to max super cruise speed and then cut power to all systems bar life support and your super cruise autopilot. The main disadvantage would be much longer travel times than Hyper space (travel time would depend on how many celestial bodies/slingshots you could make).

A travel system like this would be perfect for explorers wanting to reach the other side of the galaxy. You would have a choice:

1 - A fast Hyper space jump using lots of precious fuel with the risk of not being able to find a suitable gas giant or star to scope fuel from.

2 - A slow Supercuise Sling shot conserving precious fuel.

The GFX for this could be AMAZING

Problem is, ofc, that currently when we approach a planet in SC our speed slows down dramatically. So no slingshots while this behavior isn't changed.

Ferritt · Jun 23, 2014

I thought the science behind supercruise is based on an Alcubierre Drive. Any physicists out there know how this kind of space-time bending would be affected by a gravitational slingshot maneuver, if at all?

bliss · Jun 23, 2014

Pyros said:
Problem is, ofc, that currently when we approach a planet in SC our speed slows down dramatically. So no slingshots while this behavior isn't changed.

Although it would be cool/suicidal to do a manual slingshot I had envisioned the autopilot would handle flying the ship and calculating slingshots. I guess the current slow down is a fly-by-wire feature of the supercruise, as the gravity of a planet should speed you up :S The slingshot autopilot would disable that slow down.

FrogsFriend · Jun 23, 2014

Pyros said:
Problem is, ofc, that currently when we approach a planet in SC our speed slows down dramatically. So no slingshots while this behavior isn't changed.

Hmmm, I've sometimes found my FSD accelerating wildly when aimed just off a planet. I think this needs some more testing in-game

Crux · Jun 23, 2014

I've been messing around with this, and maybe someone else has documented the same results already...

In the Eranin system, I think, the planets there seem to be often reasonably aligned moving out from the Sun. If you're travelling to the Low Intensity Combat Zone, I've found you can line up a course which will take you past each planet in turn.

I've surmised that as you approach each planet, your "speed" (for simplicity's sake, warp theory aside) seems to increase far beyond what is actually displayed - you can see the yellow bar is far higher than the throttle indicator bar, so you might read 25c and the throttle indicator is halfway up, but the yellow bars are way higher than that. If you maneuver so as to exit the planet's influence you continue at a fast speed but seem to slow down rather quickly once you leave the gravity well or whatever.

You can do this with every planet on the way out, and to me it seems like it's faster than normal, but I haven't timed it. I've been told SC is relatively placeholder so it will be interesting to see what happens. I'm not expecting fully fledged orbital mechanics but something a little more developed to what is currently in place would be nice.

I really love the idea of mechanics like this playing into trading for example, like knowing that you can make a really speedy run to an outlying planet in a system if you time it right and fly when the planets are in your favour. It could really add some awesome depth and a whole new level of skill to trading, and even more so, courier/passenger missions once they are added.

Oh and once fuel is implemented this would only become even more interesting and useful

lefty1117 · Jun 23, 2014

I'm no physicist but I would think that for the slingshot to work our speed should actually INCREASE as we approach gravity wells, not the opposite as happens now. Plus supercruise is FTL travel is it not, so would the same sub-light slingshot mechanics apply?

Vargur · Jun 24, 2014

For them to make a slingshot valuable to the current gameplay, they would have to seriously discard a lot of physics to make it happen.
A slingshot maneuver isn't just a magical thing that multiplies your velocity.
There's basically 2 ways slingshot aka gravity assist is used.

One is for your craft to go near a planet and get caught in the gravity well, only to exit at the other side. What this does is it allows your craft to add -2 to +2 times the velocity of the planet's orbit around the sun to the velocity of the craft. This means it can be used to either speed up or slow down the craft, in reference to the sun. If you take as reference point the planet, your ship has the same velocity when it leaves the planet as when it approached.
This sort of maveuver would have absolutely no use in ED for 2 main reasons.

First, if even you would be able to get caught in the gravity well, the extra velocity you would get is negligible. Planets orbit at around 5 to 50 km/s , compare this to our frame shift drive and you can see it won't add up much.

Second, at the speeds we move in supercruise, you would just fly by the planet without it even having the chance to tug you into it's direction.
For example, if we were to represent the gravity of a planet by a silk thread, if your craft was a pingpongball (a slow craft) you would be able to swing it around with the thread. However if your craft was an anvil (a very fast craft), your thread would break before doing anything meaningful.
You would need a big chain to be able to swing it around, perhaps like the gravity from a black hole.

There's also a second way to make use of a gravity assist.
When you approach a planet, and at the periapsis (your closest approach) of your approach you accelerate your craft, then that acceleration is much more efficient than if you would perform this acceleration on your normal trajectory. This allows conventional crafts to be much more efficient in fuel usage in order to attain a certain velocity.

Unfortunately i'm not a physicist, so i have no idea how an alcubierre drive would affect these circumstances. But afaik, slingshots in the current ED model seem really both impossible and obsolete.

Maybe some lurking physicist could present a clearer picture to this all than i did.