More for less fuel?

[KerbMav]

SSTO vehicles are quite common in sci-fi movies - and they are usually rather small, so one has to ask: "Where is all the fuel that creates that big flame under it?"

In other movies you can see a relatively large craft hovering by relatively small thrusters.

How do I get so much more ooomph/mileage from my bucket of fuel?

How do I hover my space fighter with three fist sized thrusters?

[Tommygun]

Zero-point energy:

http://en.wikipedia.org/wiki/Zero-point_energy

.....or Unobtainium:

http://en.wikipedia.org/wiki/Unobtainium

[Nibb31]

Science fiction is fantasy. It just replaces magic with technobabble. So those thrusters and antigravity devices just use magic with a different name.

People who look for a rational explanation for everything they see in Star Trek or Star Wars are just ruining their own fun. It's not about being scientifically accurate. It's about telling a story. Sit back, relax, and suspend your disbelief.

Edited June 2, 2014 by Nibb31

[phoenix_ca]

Extremely high-energy fusion thrusters maybe? Hovering in place takes quite a bit of effort...you'd be better off just using a fan.

[Red Iron Crown]

Very, very high exhaust velocities.

[rtxoff]

Very, very high exhaust velocities.

Agreed, if it's going to be possible at some time then through accelerating the exhaust gases with some sort of technology. Something like electric propulsion we have nowadays but on a much more powerful scale.

[Streetwind]

It's a common theme in soft sci-fi settings (that is, those in the vicinity of the fantasy genre, or actual hybrids like Star Wars). The reality of spaceflight and its rules and limitations are unfortunately both counterintuitive and disappointing to the average guy who just wants to see cool fighters blow each other up on the movie screen.

Look at Star Citizen: big huge sci-fi game, lots and lots of detail in everything they, plenty of technobabble. Fighters and spaceships move by accurately modeled manuevering thruster power which twist and turn it and act as a piloting aid. You also have the option to toggle this "fly by wire" system on and off at will, and get real Newtonian flight physics instead, so they even dodge the "engines must be always on to move" pitfall that many space games fall prey to.

Now look at the spaceships themselves: the entire interior is available as space to walk in. There are no fuel tanks whatsoever. Every engine on every ship in the game is a jet engine, both from the physical model and the exhaust effects. They have the typical adjustable, thrust vectoring turbojet nozzles. The ships have wings and air intakes and stabilization fins. Bonus: they currently have a player-built ship model contest, with the winner making it into the game. One of the finalists is a design that does not feature jet engines; instead it has banks of glowing energy strips angled in a claw-shape (one of the judges called it "Gundam style"). Do you know what the single most voiced complaint about it is? "That doesn't look like proper spaceship engines." And with that, they mean jet engines - as if they were somehow more proper for the application than a complete fantasy construct.

No, Star Citizen is not an authentic, hard sci-fi experience by any stretch of the imagination. Much rather, it compares to some kind of uniform, infinite atmosphere field with no gravity sources in which atmospheric fighter jets can have three-degrees-of-freedom air battles (and let's not talk about the laser cannons that shoot laser "bullets" that barely move faster than the speed of sound). However, Star Citizen is also something which a lot of people really, really, really want to play. This highlights an important point: sometimes its okay to kick realism to the curb in order to create something fun. Star Citizen's combat model would not work in a real physics simulation; realistic space combat would involve computer-executed surprise attacks against vessels thousands of kilometers away, with single hits spelling the end of the entire vessel and the only human interaction factor being the act of hoping that your shot reaches the target before they manage get a return shot off. That is not fun. Nobody wants to play that.

No, we want jet fighters in space. And thus we get spaceships with wings, no fuel tanks, and jet engines. Worked for Star Wars, and will work for Star Citizen too.

Edited June 2, 2014 by Streetwind

[RenevB]

As Nibb31 said, it's mostly about suspension of disbelief. Also, I guess that ships like that are fueled with plot. If the ship has to get to orbit for the hero to escape, the ship has enough fuel get to orbit. If the hero needs to be captured, the ship will run out.

[magnemoe]

No, Star Citizen is not an authentic, hard sci-fi experience by any stretch of the imagination. Much rather, it compares to some kind of uniform, infinite atmosphere field with no gravity sources in which atmospheric fighter jets can have three-degrees-of-freedom air battles (and let's not talk about the laser cannons that shoot laser "bullets" that barely move faster than the speed of sound).

Question, can I arm the ship with an 30mm machine canon or AA rockets? as both is Mach 3+ so it should be easier to aim

[SargeRho]

I wonder if it'd be possible to build a sort of air-augmented fusion engine with enough thrust to get a (compared to Venture Star or Skylon) small SSTO into Orbit?

[magnemoe]

I wonder if it'd be possible to build a sort of air-augmented fusion engine with enough thrust to get a (compared to Venture Star or Skylon) small SSTO into Orbit?

I think the problem with fusion engines is that for an high performance fusion engine you need an vacuum camber where you let the fusioned end product escape as a beam, air will enter this hole and the fusion process will stop. Same with ion engines, you can not use them in atmosphere.

Option would be to run it as a power plant and use the power to heat or move air, main issue with any high isp engine is that you will get problem with waste heat, one option might be to leak steam from the cooling system into the jet engines and heat it more with microwaves, this will give you an high trust option.

[Aghanim]

I have think about coupling ion beam from the vacuum of DPF reactor to a scramjet high pressure. However, it is possible to do that, by using plasma window.

Look at this: http://en.wikipedia.org/wiki/Plasma_window It is the closest thing that we have to a fictional force field

A large craft hovering using a small thruster? Probably possible. A SSTO without fuel tank? Sorry, invent some kind of reactionless drive first before thinking about that

Edited June 2, 2014 by Aghanim

[KerbMav]

A SSTO without fuel tank?

Not without a fuel tank, but often these crafts are to small to hold any significant amount of fuel, let alone to reach orbit.

[Ayo99]

Higher ISP = More for less fuel

[WinkAllKerb'']

t~ a few more waste, bah who care * shrug* may be we can learn something unexpected even from some more waste as it never already happen too.

Edited June 2, 2014 by WinkAllKerb''