Why FTL Starships Should Never Land On A Planet....

[Bamax]

This dawned on me during a discussion elsewhere on the interwebs (as you Euros like to call it, here in the States we just call it the internet).

The energy required for FTL is staggering.... even with adjustments to lower it based upon the theortical warp drive of alcubierre (instead of one Jupiter they pared it down to about the mass of the voyager probe converted into energy).


That kind of energy is more than your average nuke already.

In view of all this I decided to take a different approach than Star Wars or even Star Trek.

In my scifi universe... massive FTL carriers are what take spaceships across interstellar distances, but spaceships are like the solar system equivalent of dropships.

Yes they have enough power/fuel to planet hop a few times, but they really do not have the fuel or power to travel all over the solar system.

FTL carriers do though.

So typical practice is to park the FTL carriers in orbit about a light second out. Then undock any solar 'dropships' going to the planet.

Which will need to return to the FTL carrier if they ever want to leave the solar system.

Think of the FTL carrier as a mothership with explodium so potent you need to park it in orbit a light second away, carrying spaceships with less power and range which also are safe to land or take off from planets with.

[StarCruiser]

That's basically the Frank Herbert 'Dune' Highliner in a nutshell.

Huge FTL (albeit jump ship/dimensional gate or..?) ship - disgorges lots of smaller craft in the destination system.

[spacewhale]

https://www.eyeofmidas.com/scifi/Turtle ... tTaken.pdf

FTL could be something easy that we haven't figured out yet.

[icekatze]

hi hi

Considering that FTL travel is fictional, an author can make up whatever energy requirements they want. Rather than that, the energy and structural requirements for lifting a ship out of a gravity well makes it a good idea to separate any large space mission into an interstellar craft that doesn't need the heavy structural supports for gravy, and landing craft. Also, one doesn't want to fire off the high efficiency in space fission/fusion rockets in an atmosphere.

A light second is maybe a bit excessive for distance for the mass of voyager converted to energy, but probably not enough for Jupiter.

[Bamax]

That's basically the Frank Herbert 'Dune' Highliner in a nutshell.

Huge FTL (albeit jump ship/dimensional gate or..?) ship - disgorges lots of smaller craft in the destination system.

Sounds that way but is a wee bit different since I left out some details.

Engines use propellantless antigravity ray thrusters that rely on super batteries for power.

Unlike normal batteries they can store enough electricity to equal their mass. Meaning a fully charged kilogram battery woukd weigh 2 kilograms.


As such, it as not as if spaceships cannot take extra power packs from the mothership to extend their travel range in solar systems, they just choose not to for safety when going to planets usually.

Since batteries are so power dense, van size shuttlecraft like in star trek are thus possible.

[gaerzi]

Considering that FTL travel is fictional, an author can make up whatever energy requirements they want.

Exactly. The method of FTL travel, its energy cost, as well as the actual energy storage capacity of the starship, are all dictated by plot as a true hard-sci-fi story would not have FTL at all anyway. Quite often in space opera stories, ships have functionally unlimited energy. There may be mentions of refueling or something, or maybe needing to send an away team to mine some dilithium crystals or whatever, but unless the plot demands it, energy is just not a worry.

One amusing take on the subject I've seen was in Irregular Webcomic's space theme. There, ships can "skew" into hyperspace for FTL travel and this process of "skewing" is instant and can actually safely be done on a planet. So starships do not take off from the starport. They just skew away directly. Admittedly, this does make desperate escape scenes a lot less dramatic.

In the Elite/Frontier series, you could go into hyperspace from within a planet's atmosphere, but since hyperspace travel creates very radioactive "clouds" at both the exit and entry points, doing that while too close to a planet is a crime. Other settings may require an acceleration to relativistic speed before entering hyperspace (so you want as perfect a vacuum as possible in your path), or being far away from gravity wells, etc.

[icekatze]

hi hi

Being able to FTL onto a planet would make planets extremely defenseless places to live. So that's a little bit dramatic in its own right, at least.

Also, I've been playing a bit of Elite: Dangerous lately, and I had no idea that frame shifting within a planet's atmosphere created fallout. I've been irradiating all kinds of newly discovered bacterium...

[Bamax]

hi hi

Being able to FTL onto a planet would make planets extremely defenseless places to live. So that's a little bit dramatic in its own right, at least.

Also, I've been playing a bit of Elite: Dangerous lately, and I had no idea that frame shifting within a planet's atmosphere created fallout. I've been irradiating all kinds of newly discovered bacterium...

And that is the reason the choice of scifi tech matters.

Making up convoluted reasons for why technology so powerful is not misused can break suspension of disbelief of the author... to say nothing of readers.


I do believe scifi should have more power/energy than modern, but unlimited is not a word I really like.

I like for things to cost something.... hell, everything in life does.

Nothing comes without cost or consequence... to get something you gotta give something.

For all intents and purposes FTL carriers would have way higher travel ranges than the ships they carry, but even that would be mission based.

For example an exploratory FTL carrier trying to emulate the USS Enterprise 5 year mission would be arguably the most powerful ship in the local galaxy... since it needs it to accelerate for weeks on end if necessary.

I would only provide drop spaceships with just enough energy to land and get back to the carrier in orbit.

So no fancy flying dogfights in atmosphere with spaceships.

Aeroplanes and jets can do that far better without requiring a super dense energy source.

[gaerzi]

Also, I've been playing a bit of Elite: Dangerous lately, and I had no idea that frame shifting within a planet's atmosphere created fallout. I've been irradiating all kinds of newly discovered bacterium...

Well that was true in Frontier: Elite II and Frontier: First Encounters. I don't know if they've kept it in Elite: Dangerous, nor if it was a thing in the original Elite (I think not, I believe there were only space stations in that, planetary landings was a new feature from Frontier IIRC).

[Bamax]

For what it is worth, as fantastical as Star Trek teleporters are, they actually are a very practical thing to do for FTL capable starships.

Since why land something so freakishly powerful when you can just beam down or beam up whatver you want.


The problem then becomes how to protect planets from starships simply beaming explosives down.

Which I suppose could be easily solved by scifi shield domes covering cities or secure areas, and perhaps solid special concrete surfaces that reflect transporter beams right back at the ship so that anything teleported is beamed right back up before it materializes.

The more obvious solution is to fight fire with fire.

Orbiting starship giving you trouble on a planet?

Teleport a bunch of steel in front of it... starship will slam into it at moving at 5 miles per second.

Wanna ruin starship fleets further? Put a bunch of teleporter satelites in orbit.

No one will dare do anything stupid if they do not want to die.

[Sweforce]

Interstellar travelling ships, FTL or not really should be huge I think unless it is a probe. And in any case interstellar or interplanetary, the one thing that protect against cosmic radiation are mass. A small ship with a thin hull isn't that but if your ship is a mile long, boxy thing, chances are that you can spare that mass by having a thick hull.

Lacking a thick hull there is the other option of reducing the crew's exposure to radiation by simply minimizing travelling times by being really fast. If you can get to Mars in four weeks then you will fare better then if it took four months.

[CrimsonFALKE]

That's basically the Frank Herbert 'Dune' Highliner in a nutshell.

Huge FTL (albeit jump ship/dimensional gate or..?) ship - disgorges lots of smaller craft in the destination system.

Sounds that way but is a wee bit different since I left out some details.

Engines use propellantless antigravity ray thrusters that rely on super batteries for power.

Unlike normal batteries they can store enough electricity to equal their mass. Meaning a fully charged kilogram battery woukd weigh 2 kilograms.


As such, it as not as if spaceships cannot take extra power packs from the mothership to extend their travel range in solar systems, they just choose not to for safety when going to planets usually.

Since batteries are so power dense, van size shuttlecraft like in star trek are thus possible.

Star trek is soft science those shuttle craft have no room for rcs fuel. They'd be a one way escape pod that drifts though the void at best. Battletech does this pretty much the best with drop and jump ships.

[Bamax]

That's basically the Frank Herbert 'Dune' Highliner in a nutshell.

Huge FTL (albeit jump ship/dimensional gate or..?) ship - disgorges lots of smaller craft in the destination system.

Sounds that way but is a wee bit different since I left out some details.

Engines use propellantless antigravity ray thrusters that rely on super batteries for power.

Unlike normal batteries they can store enough electricity to equal their mass. Meaning a fully charged kilogram battery woukd weigh 2 kilograms.


As such, it as not as if spaceships cannot take extra power packs from the mothership to extend their travel range in solar systems, they just choose not to for safety when going to planets usually.

Since batteries are so power dense, van size shuttlecraft like in star trek are thus possible.

Star trek is soft science those shuttle craft have no room for rcs fuel. They'd be a one way escape pod that drifts though the void at best. Battletech does this pretty much the best with drop and jump ships.

Well.... yes. But in theory it could still be done if RCS was energertic enough as well as the liftoff engines.

Realistically you would want a tail lander shuttle to avoid needing extra landing engines besides the main ones. Perhaps a pair of side rockets on the main ship vertical body.

That said... in theory to get an SSTO you need crazy high energetic exhaust speeds.... the same kind that creates so much heat your shuttle engine would melt anyway.

If there was a more direct process of accelerating propellant without massive waste heat being a factor... like tactile kinetic reaction chambers that accelerate propellant out as it touches the the walls, then maybe you could pulse fire to save propellant as you pulse fire to orbit at crazy high exhaust velocities. You WILL leave a crater behind you though.