How Much Delta V Is Necessary To Get Around The Solar System?

[Spacescifi]

 

Here is the scifi scenario:

We have scifi drives that run off batteries (no propellant required) that are 3 meters in radius and a meter thick, and weigh a ton each (disc shaped). Each battery provides 30 min of thrust... throttling thrust to max or low won't effect the thrust time for better or worse. It will run the battery dry in 30 minutes of constant engine acceleration either way.

Thrust for the scifi engine is always sufficient for however heavy a ship is for it's stated max load to move it around efficiently. Once batteries drain you need more, otherwise you will be drifting in space with no sublight engine power.

Goverment regulations: It goes without saying that scifi goverments have to regulate this kind of thing for civillian freighters and passenger liners.

Civillian vessels: Are regulated to not have max engine thrust higher than 3g.

Goverment vessels: Manned vessels have a max thrust of 6g. Robotic unmanned vessels can do 20g.

Millitary/exploration vessels: Use a scifi reactor (not a battery) that grants... 1000 hours of thrust before reactor fuel is exhausted. Much like the battery drive throttling thrust won't effect thrust time and the drive requires no propellant.

Solar system travel Regulations: Civillian ships need a max amount of batteries they are allowed to carry. Likely it will be based on their travel itinerary.

So to go to the moon and back doing 1g may take about 12 batteries with a payload *fuel* weight of 12 tons.

To go to Mars and back under 1g? LOL. Problematic. The rocket equation STILL MATTERS. Because at some point your battery to payload ratio becomes ridiculous enough if you just pile on too many batteries that it will go past max payload and lower engine thrust down from stated max levels.

Even so, the setting does have warp drive which at least translates the ship's position across space. Changing the trajectory and speed the fastest way involves using the battery powered 30 min each battery drive.

Using warp AND the battery drive, what is a reasonable smount of batteries for a civillian vessel to have? 2 hours worth (4 batteries)? Since it goes without saying that the said vessel could accelerate at 3g for 2 hours and attempt to ram Earth. Goverments have to regulate that kind of thing.

What number of batteries is sufficient to explore explore the solar system?

I think 2 hours worth is fine. Since warp will get a vessel close enough to it's planet of interest, and every planet in our solar system (except the inner planets like Earth) orbit slower than Earth anyway.

Which means:

Takeoff: About ten minutes or less to low Earth orbit using 3g.

Transfer: Warp drive at light speed. Drop out in low orbit of oh... say Mars. Use battery engines to slow down for mars low orbital speed. should not take more than ten min at 3g.

What have we got left? A little over an hour and a half left of battery power for sublight engines.

With about ten more minutes of thrust we wiill drain our first battery... to land on Mars.

So it seems that 3g at 30 min is good enough to reach LEO, transfer speed, and even land on another body... so long warp transfer of vessel's position in space is applied.

 

What do you think on this? Did I get it right or miss or overlook something?

Edited October 18, 2020 by Spacescifi

[SOXBLOX]

2 hours ago, Spacescifi said:

...miss or overlook something?

Yes. What if some wise guy slaps a nuclear reactor or solar panels on his ship?

[kerbiloid]

Solar System Delta-V map

Spoiler

 

[Spacescifi]

25 minutes ago, SOXBLOX said:

Yes. What if some wise guy slaps a nuclear reactor or solar panels on his ship?

 

I see what you are up to.... clever even.

The scifi batteries are not rechargeable. Neither do they make a rechargeable one and for good reason.

Even if someone DID make a rechargeable battery, you know it would take a long time to charge up enough power and propel any ship with a payload of reasonably profitable mass (100 tons), not counting ship mass itself. Using only solar or nuclear anyway.

 

The industrial factories that make the batteries use several AM reactors to charge the batteries in a far more reasonable amount of time.

No goverment in their right mind is handing AM reactors out to spaceships owned by civillians.

Edited October 18, 2020 by Spacescifi

[kerbiloid]

1 minute ago, Spacescifi said:

The industrial factories that make the batteries uses several AM reactors

So, instead of charging the batteries directly from the energy source, they first produce AM, then charge the batteries via the AM intermediate reactor, spending most part of produced energy with no purpose.

[Spacescifi]

11 minutes ago, kerbiloid said:

Solar System Delta-V map

  Hide contents

 

 

Thanks.

So I take it I was right about orbiting objects farther from the sun orbiting slower than the inner worlds?

Which means flying to an inner world will cost more delta v than an outer one usually?

8 minutes ago, kerbiloid said:

So, instead of charging the batteries directly from the energy source, they first produce AM, then charge the batteries via the AM intermediate reactor, spending most part of produced energy with no purpose.

 

AM reactors charge the batteries faster than more conventional means.... that's the story I am sticking to anyway.

They are scifi reactors so they must do something really amazing to charge batteries with enough power to provide thrust to engines that do not use conventional mass propellant.

The fact the scifi batteries can even contain that amount of energy is also scifi.

Edited October 18, 2020 by Spacescifi

[kerbiloid]

18 minutes ago, Spacescifi said:

AM reactors charge the batteries faster than more conventional means...

They can't because the battery charging speed is limited.

They just heat the air.

AM is not a source of energy, it's a weird intermediate battery.

Edited October 18, 2020 by kerbiloid

[Spacescifi]

13 minutes ago, kerbiloid said:

They can't because the battery charging speed is limited.

Yes charging speed is limited when using conventional means

Using a scifi AM reactor is rather... unconventional though.

Just like the battery itself is.

For all we know the reactor could be doing something at the quark level with the battery to charge it faster.... very unconventional.

Even more so that the battery can take that and survive.

This is getting off OP though.

Edited October 18, 2020 by Spacescifi

[Gargamel]

4 hours ago, Spacescifi said:

Which means flying to an inner world will cost more delta v than an outer one usually?

Why haven't you picked up KSP yet?   It's right up your alley.

[Spacescifi]

9 hours ago, Gargamel said:

Why haven't you picked up KSP yet?   It's right up your alley.

 

You make a valid point.

Want full honesty? I will PM you.

[linuxgurugamer]

8 minutes ago, Spacescifi said:

 

You make a valid point.

Want full honesty? I will PM you.

Curious here as well

 

Edited October 18, 2020 by linuxgurugamer

[RealKerbal3x]

6 minutes ago, Spacescifi said:

 

You make a valid point.

Want full honesty? I will PM you.

Is it because you know it'll ruin your enjoyment of science fiction?

It's a sad side effect

[linuxgurugamer]

It doesnt take a huge amount of dV to get to the outer planets, if you don't  mind taking years to make the trip.  Faster trip  needs more dV

[Spacescifi]

Just now, linuxgurugamer said:

It doesnt take a huge amount of dV to get to the outer planets, if you don't  mind taking years to make the trip.  Faster trip  needs more dV

 

Not with warping at lightspeed! It will allow you to skip all that useless SPACE in between and allow you to use engines for what they can get by with less ISP... orbit or land.

3 minutes ago, RealKerbal3x said:

Is it because you know it'll ruin your enjoyment of science fiction?

It's a sad side effect

 

Oh not at all... that did not happen too much... as the scifi I like most (B5 and DS9) has good enough character and plot that I can ignore the bad science.

[RealKerbal3x]

1 minute ago, Spacescifi said:

Oh not at all... that did not happen too much... as the scifi I like most (B5 and DS9) has good enough character and plot that I can ignore the bad science.

Yeah, fortunately I can still watch stuff like Star Trek as it's so far removed from real science. 

But if you do get KSP, be prepared to never take movies like Gravity or Interstellar seriously again. You'll constantly be pointing out 'hey that has way too much dV!' and 'that maneuver makes no sense!'

[Spacescifi]

3 hours ago, RealKerbal3x said:

Yeah, fortunately I can still watch stuff like Star Trek as it's so far removed from real science. 

But if you do get KSP, be prepared to never take movies like Gravity or Interstellar seriously again. You'll constantly be pointing out 'hey that has way too much dV!' and 'that maneuver makes no sense!'

 

I will put it this way... any time I see a flamey rocket nozzle SSTO take off or land and do it AGAIN and AGAIN without refueling propellant, or with a low propellant to payload ratio.... my eyes start rolling.

I rather see rockets based on real science or even theoretical science since we understand them so well.

If you must cheat then make stuff up, but do NOT pretend rockets can work miracles without the requisite power or propellant.

Actually let me rephrase that... to do any of the stuff in the movies you need at bare minimum 2 things.

1. Requisite power. Movies and TV throw around fusion power like it's a make-it-so button. Overlooking or ignoring the melt-the-walls heat the fusion creates. No known material... not steel, not even tungston or quartz can stand up to fusion heat. Magnetic fields as so far are... slippery 'hands'.

2. Requisite propellant: The great thing about propellant is you can dump a lot of engine heat into your propellant exhaust. The bad thing is that too much will lower your payload to propellant ratio... unless you use staged dumping of rockets, but that only works ONCE. On launch. Without propellantengine heat becomes a greater issue the greater thrust you create.

Gravity was good for the most part. Clooney was dumb enough to die for no good reason if IRL physics are in play. Besides having a spacesuit that had a lot more propellant gas than the ones IRL.

Edited October 18, 2020 by Spacescifi

[kerbiloid]

8 hours ago, Spacescifi said:

Not with warping at lightspeed! It will allow you to skip all that useless SPACE in between

Or just select another location in popup menu. Were on Mars, appear on Pluto.

Same scientific to date.

Just recollapse your wave-function at Pluto.
Or just switch your multiverse focus position to the proper version of Universe with you on Pluto.