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How will you get to one of the planets?


Candre

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Got a lot of responses :)

I reasoned that a Munar 'slingshot,' if I\'ve been using the term correctly, would put me in a very high, circular orbit around Kerbin for just the dV of a Munar insertion orbit, which would then allow for an express shot out of Kerbin\'s SOI. Now that I\'ve read up on the Oberth effect, it is probably more efficient to just burn after making orbit. Maybe it could be more efficient, as it sounds like a bi-elliptic transfer, but only if *something about a 11.4 ratio*.

Cool ideas everyone. I\'d like to see the smallest ship one can get to one of the planets, or possibly a spaceplane design that *might* work on a body with an atmosphere.

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Getting close enough to Kerbol that you can circularize and use the Planetrise burn method is ridiculously fuel-expensive. You\'d be looking at circularizing at about 10,000 km altitude over Kerbol, and you\'d need a spacecraft capable of over 120km/s of delta-V to circularize that low, and burn out of that orbit again.

In that case:

• First, exit Kerbin\'s SOI.

• Next, get into an orbit with an apoapsis the same as Murz\'s orbit and a periapsis slightly lower.

• WARP

• Enter Murz\'s SOI

• Don cool sunglasses

• Circularize barely within Murz\'s atmosphere, wait for orbit to slowly decay, parachutes + small amount of thrust to land

• Take off again

• Rendezvous with orbiting rocket, EVA all crew into it

• Exit Murz\'s SOI

• Get into an orbit with an apoapsis the same as Kerbin\'s and a periapsis slightly lower

• WARP!

• Land on Kerbin.

Or, if/when that doesn\'t work:

• Give up

• Use Mechjeb

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Maybe (might be a bit easier) we could go to minmus and extend our orbit from there? Or even possibily use it as a gravity boost toward a higher orbit or another planet\'s SOI. But an ion engine and solar panels wouuld be the best way if that is implemented in 0.17.

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Just did a Mun gravity sling. Flew out to Minmus and then slung past the Mun. I was able to get out to a 19 Billion meters circular orbit with a tiny rocket (on the back of a plane). Based on this. The sling method seems like the best way to get to a planet and back.

screenshot144a.png

capsule, full fuel tank, small engine, 4 landing legs, decoupler, full fuel tank and large engine.

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Just did a Mun gravity sling. Flew out to Minmus and then slung past the Mun. I was able to get out to a 19 Billion meters circular orbit with a tiny rocket (on the back of a plane). Based on this. The sling method seems like the best way to get to a planet and back.

screenshot144a.png

capsule, full fuel tank, small engine, 4 landing legs, decoupler, full fuel tank and large engine.

Take the same spacecraft, and put it in a low circular orbit around Kerbin (~100km or so).

Wait until you cross the midnight line, and then burn prograde.

Keep burning until the patched conics show that your eventual apoapsis in Kerbol orbit will be at 19Gm.

Then shut off the engines, coast out of the Kerbin SOI, into the Kerbol orbit, out to the 19Gm apoapsis, and circularize.

Compare how much fuel you have when you do so .

Edit: Admittedly the rather egregious low-throttle fuel-efficiency bug will muddle the results significantly, if triggered. It\'s capable of eking dozens of km/s of delta-V out of a single fuel tank.

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Here\'s what I did just now as a proof of concept using the Anvil I mod rocket and some KW parts (3x 1m fuel tank and the most powerful 1m engine). There needs to be three phases of burn (and I do mean phases, multiple stages may be involved in each phase). One phase to take off from the surface of Kerbin, which could be SRBs and LFEs, 'heavy configuration' with crossfeeding parallel fuel tanks, anything to get out of the atmosphere. Second phase is to get to orbit, obviously. The third phase is to do the transfer.

The rocket needs to get mostly out of the atmosphere before the orbital stage is initiated. Then the orbital phase needs to put the ship into an orbit, and the transfer phase needs to have enough fuel to accelerate to escape velocity and put the apoapsis at the required distance. There has to be a clean break between each phase, for example you can\'t complete the orbit with the transfer stage or you won\'t have enough fuel.

This is how I did it, you could also use teh Orbital Construction mod to build a big rocket in orbit and send it on its way.

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Mission to Mars .... isn\'t that the one where the ship has engine problems during orbital insertion and to avoid flying off indo deep space they EVA across to a ship that\'s already in orbit. Completely ignoring that they need to spacewalk away the excess delta-v left over from the failed insertion maneuver.

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*WARNING* Wall of text incoming.

Mission

First, like some others, I\'d build an orbital fuel depot for (of course,) refuelling other ships, but also to serve as a dry dock for the construction of the interplanetary vessels. For a mission to another planet, (Murs?) I\'d send three out, one at a time. The first would serve to map out the surface with the ISA MapSat plugin in order to locate the best possible landing area, as well as to land some preliminary base components (solar panels, rovers, ect.). The second ship would, save for cargo, be virtually identical in mission and in configuration.

The last spacecraft would be manned, and rendevouz with the others in order to form a temporary space station. Its lander would carry three Kerbonauts to the surface in order to do some science. They would stay in on the surface for approximately six months, supplies being delivered beforehand by the first and second ships\' landers. When the time comes for return, they would blast off in their ascent capsule and dock with their ship in order to transfer their crew. The now useless ascent capsule would then use its remaining fuel to deorbit. No sense in carrying dead weight.

Upon returning to Kerbin, the manned spacecraft would once again rendevouz with the fuel depot, where a surface-to-orbit spacecraft would be waiting in order to bring them back to the surface. For another mission, all the transfer spacecraft would need would be to receive a new (possibly manned) payload and to top off the tanks.

Design

The transfer spacecraft would be composed of a single Kosmos or BACE node surrounded by propulsion, habitation, docking, and payload modules.

On the 'top' and 'bottom' would be the docking nodes. These would simply be pressurized corridors tipped with a docking ring.

On the 'left' and 'right' of the node would be the habitation modules, composed of either BACE or (more probable) Kosmos modules. Simple.

In 'front' would be situated the payload rack, which does exactly what it says on the tin. The lander would dock to the tip of this module.

Last, but certainly not least, would be the propulsion module. This would be composed of a Kosmos Expedition fuel tank feeding one of their NERVA-style nuclear-thermal rocket engines. Feeding off of liquid hydrogen, this would give the craft all the delta-V it could ever need.

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I think people would find it more appealing if you colored it, like this:

Mission

First, like some others, I\'d build an orbital fuel depot for (of course,) refuelling other ships, but also to serve as a dry dock for the construction of the interplanetary vessels. For a mission to another planet, (Murs?) I\'d send three out, one at a time. The first would serve to map out the surface with the ISA MapSat plugin in order to locate the best possible landing area, as well as to land some preliminary base components (solar panels, rovers, ect.). The second ship would, save for cargo, be virtually identical in mission and in configuration.

The last spacecraft would be manned, and rendevouz with the others in order to form a temporary space station. Its lander would carry three Kerbonauts to the surface in order to do some science. They would stay in on the surface for approximately six months, supplies being delivered beforehand by the first and second ships\' landers. When the time comes for return, they would blast off in their ascent capsule and dock with their ship in order to transfer their crew. The now useless ascent capsule would then use its remaining fuel to deorbit. No sense in carrying dead weight.

Upon returning to Kerbin, the manned spacecraft would once again rendevouz with the fuel depot, where a surface-to-orbit spacecraft would be waiting in order to bring them back to the surface. For another mission, all the transfer spacecraft would need would be to receive a new (possibly manned) payload and to top off the tanks.

Design

The transfer spacecraft would be composed of a single Kosmos or BACE node surrounded by propulsion, habitation, docking, and payload modules.

On the 'top' and 'bottom' would be the docking nodes. These would simply be pressurized corridors tipped with a docking ring.

On the 'left' and 'right' of the node would be the habitation modules, composed of either BACE or (more probable) Kosmos modules. Simple.

In 'front' would be situated the payload rack, which does exactly what it says on the tin. The lander would dock to the tip of this module.

Last, but certainly not least, would be the propulsion module. This would be composed of a Kosmos Expedition fuel tank feeding one of their NERVA-style nuclear-thermal rocket engines. Feeding off of liquid hydrogen, this would give the craft all the delta-V it could ever need.

See?

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Guest butt head

I think people would find it more appealing if you colored it, like this:

-snip-

thanks for setting it up like this i think it was easyer to read although it may be considered spam?(i would like it to be left up-hint hint wink ;) wink ;) mods?)

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Mission to Mars .... isn\'t that the one where the ship has engine problems during orbital insertion and to avoid flying off indo deep space they EVA across to a ship that\'s already in orbit. Completely ignoring that they need to spacewalk away the excess delta-v left over from the failed insertion maneuver.

lol ya but hopefully the engine won\'t fail in KSP :P

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Mission to Mars .... isn\'t that the one where the ship has engine problems during orbital insertion and to avoid flying off indo deep space they EVA across to a ship that\'s already in orbit. Completely ignoring that they need to spacewalk away the excess delta-v left over from the failed insertion maneuver.

Engine problems caused by meteoroids striking the exposed fuel lines, probably left exposed because it was a rushed mission. There was some science thrown to the wind as far as their attempt at joining with the craft in orbit, but oh well, it\'s a scifi movie.

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To get to Murs, I\'d take my largest ship with lander, and escape from Kerbin in the direction of its orbit so I am travelling faster than Kerbin. I\'d then burn gradually until I entered the planet\'s SOI at the right height, timewarp, retroburn, descend, ascend, orbit, then escape back to Kerbin. If it wasn\'t possible with stock parts no plugins why would they be adding planets now?

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Take the same spacecraft, and put it in a low circular orbit around Kerbin (~100km or so).

Wait until you cross the midnight line, and then burn prograde.

Keep burning until the patched conics show that your eventual apoapsis in Kerbol orbit will be at 19Gm.

Then shut off the engines, coast out of the Kerbin SOI, into the Kerbol orbit, out to the 19Gm apoapsis, and circularize.

Compare how much fuel you have when you do so .

Edit: Admittedly the rather egregious low-throttle fuel-efficiency bug will muddle the results significantly, if triggered. It\'s capable of eking dozens of km/s of delta-V out of a single fuel tank.

The sling uses less fuel. I only burnt to Minmus range and waited for low Mun, low Kerbin pass-by which through me out to 19Gm. I know about the fuel glitch which is why I used 100% throttle. I only just got out that far but it is doable with small rockets.

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I would probably point my rocket at it and fire the engines until nothing\'s left.

And miss, and fail horribly because I didn\'t plan the mission properly.

But remember: New parts are being added, there might be super-efficient low thrust engines for use in interplanetary space, or different SRBs and fuel tanks that may mean heavy lifter rockets are a lot easier.

I hope so, right now, using the bigger parts is extremely hard...

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The sling uses less fuel. I only burnt to Minmus range and waited for low Mun, low Kerbin pass-by which through me out to 19Gm. I know about the fuel glitch which is why I used 100% throttle. I only just got out that far but it is doable with small rockets.

I\'m sorry, I can\'t tell from your response, and don\'t want to assume. Did you attempt the provided control experiment?

Edit: Figured I\'d try myself, full-on-burns, all the time, using a spacecraft that consisted of just the last stage of yours, As I neither have your .craft file, nor am I particularly good at flying spaceplanes, starting from a 100km circular orbit to take advantage of the Oberth Effect.

WQQihl.png

Waited until I crossed the Midnight line, and did a full on burn until my projected escape path put me into an orbit with an apoapsis of 19GM from Kerbol.

q0uqzl.png

LXfxMl.png

I then coasted out to that apoapsis and circularized, again with full on burns.

ZkT4Yl.png

0cPpsl.png

Fuel at start 400, fuel at end, 117.1. A little over 2/3 of a tank of fuel. Could have gone far farther, and circularized much higher. Probably could have escaped Kerbol.

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With the new parts, hopefully it will be easier for such things. I\'ve already orbitited around Kerbal a few times and returned to land on Kerbin with a space plane. The plane is able to reach orbit, but because I had to switch out an aero-spike engine for a liquid fuel engine, it doesn\'t seem to be able to get much past an orbit. Hopefully the new parts include a high efficency engine I can attach a decoupler to, and il be all set for visiting and returning from a planet 8)

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If there is any significant atmosphere on the planet, the only way I can imagine returning is by leaving one ship in orbit, and landing with a second ship. It would be easier with docking, but two missions will work for now.

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