Why can't we just attach two airplane engines on both sides

>>8794292
I have lots of questions like this too. Should have majored in rocket science :(

>>8794292
Better yet we could put a rocket engine on the bottom of the rocket

Jets quickly become less efficient as you gain altitude and the air gets thinner. The highest cruising altitude of a commercial jet has been 18 km, which is about double the standard. Space doesn't start until 100 km

>>8794298
There's a reason civilian aviation doesn't use rocket engines.

>>8794313
>quickly
That's the part that matters because of enormous air resistance and gravity.

>>8794313
Space is fake
Earth is flat
Polaris is the center
NASA is a government agency

>>8794322
Gravity is a lie.
Density is the primary reason objects sink or rise in a liquid or gas.
Example, blimps, submarines

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>build large rocket similar to the space shuttle but with an enclosed fuel tank
>takes off like a normal aircraft, using a runway thanks to the large 'take-off wings' that sheathe over the smaller heat protected landing wings
>once it reaches maximum altitude the large wings break away and the shuttles rocket fires using full power to enter orbit
>lands on a runway like the regular shuttle
disposable wings are a lot cheaper than disposable rockets, also they could be light enough to parachute down safely.
where do i accept my nobel prize?

>>8795132
Adding wings and a get engine mechanism so that you can use a less powerful form of propulsion doesn't make sense. Just use that weight to load up more jet fuel.

>>8795141
it can use the rocket engines a lot more efficiently when taking off like a plane and then switch to full power for the last stretch.

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>>8794292
For small rockets it makes perfect sense, but for larger rockets it's not really worthwhile because jet engines are way weaker (if more efficient) than rockets.

If you want to fly your rocket sideways to get to a high altitude you need so much structural reinforcement that it's not even funny, rockets are heavy due to all the fuel and only strong in only one dimension.

Pic related, it's an anti-ballistic missile missile being used as a satellite killer by an F15. Usually it's not able to reach space.

>>8794335
You realize bouyancy is a direct result of gravity right? You are basically saying that gravity isnt real, and instead you propose that things "sink" in the atmosphere because they have more weight (see gravitational attraction) per unit of volume than said atmosphere.

>>8794333
holy shit it's a conspiracy post that actually got 1 out of 4 things correct
>but which one?
>xfilestheme.wav

>>8794292
Airplane engines usually rely on an atmosphere. There's usually no atmosphere in space. So you need to bring the oxygen with you.

>>8795150
>the last stretch
>actually 90+% of the journey
>would be require more acceleration and a change of direction after doing that little plance stunt

Brainlets first "invention" huh

Two would not be enough. For comparison some numbers. First stage of a Saturn rocket has an output of 6700 kN. One jet engine CF6 has an output of 185 kN. (credits to wikipedia for data) These can be assumed to be in the ballpark of what is necessary and what is possible. You would need about 36 turbojets to get the same output as the rocket engine. One big problem would be the amount of parts to go wrong. Of course building bigger jet engines would be possible to some extent. The amount of fuel they require would be similar. The jets may end up weighing more. Theoretically the suction of air, from around the rocket body to feed the turbojets would provide some additional lift, and probably destabilize the rocket in the process.

Lets forget about jet engines and just concentrate on making a rocket take off like a plane from a runway. Lets say we could make detachable wings with a fuselage frame that cradles the rocket so that the rocket does not have to bear the stresses of the take off. Wouldnt the rocket burn a lot less fuel because it doesnt have to overcome its own gravity to get moving? It would excellerate extremely quickly and gain altitude very rapidly. The wings/fuselage would be detached around 50,000 feet where air no longer supports the wings. Wouldnt such a rocket use a lot less fuel and so be a lot lighter/smaller?

>>8797250
That's a lot of extra effort just to get through the first 5% of ascent.

Sure, it might help marginally if engineered very well, but so far it just hasn't been worth the effort

>>8797250
No
The "problem" with rockets is that they are lowish efficiency, due to their method of operation and the fact they carry their oxidizer

Taking off horizontally doesn't change that.
The point of taking off horizontally is that you can use a lower thrust to weight air breathing jet engine

But remember this, the Falcon 9 weighs 1 million lbs on the pad, no plane ever built could lift that.

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← single stage to orbit (SSTO)

>>8797174
>First stage of a Saturn rocket has an output of 6700 kN
Actually each engine of the first stage had that output, and there were 5 engines on the first stage.

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>>8796602
lol underrated

why not fly something to space with a string attached and leave it there, that way people can come up and down the string whenever they want

>>8798260
fuck space elevators

We seriously need to learn how to manipulate gravity.

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>>8794292
Such a plane would drop down as soon as it exist the atmosphere because of no aerodynamics in space and then it would burn up.

That's why they use multi-stage rockets so that the space capsule can come down with a parachute. There's no way they can make a parachute big enough to land a plane.

>>8794335
No, it isn't. They've already detected gravity waves so objects can sink and float just the way as it does in liquid/gas waves.

>All these retards throwing around the word "efficient"

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Kek

why didn't you come out with this theory in the 60s?

do you have any idea how much energy we have wasted because of you?

>>8795132
the delta-v and altitude gained from a launch like that isn't worth the mechanical and engineering costs

>>8798283
>Such a plane would drop down as soon as it exist the atmosphere
>then it would burn up
>That's why they use multi-stage rockets
>so that the space capsule can come down with a parachute
>There's no way they can make a parachute big enough to land a plane

Most brainlet post of 2017 so far?

>>8794292
Skylon has been either ignored or laughably under-funded for decades.

Last I heard the Chinese stole the designs, which is good, because they can sctuslly get shit done.

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>>8794292
on my way to mars. wish me luck

>>8798139
Thanks. That would make it even more impossible then. Imagine 180 turbojets in a grid. Would the airflow keep them cool enough or would they seize from excessive heating?

does anyone know what percent of rocket stages are used up going through the the air atmosphere (the first 30,000 ft)?

I recall that the largest stage of a Saturn V, about 1/3 of the size of the rocket, is burnt just going through air atmosphere