sgt_flyer

The problem is, your experiment is altered by the presence of two elements : air and gravity. In a zero G vacuum environment, the results would not be the same. And we can even include ground friction - even of you are able to minimize track friction, you can't remove them - in the end, it seems that what your contraption do, is to make a sudden move in one direction, then a slow reset - the slow reset having less effect than the fast one because of the air and ground friction. This would not work in a zero g vacuum environment.

I think they also worked on a new control system, to prevent the stage from spinning during the freefall part of the descent. (That's what prevented the previous return over water from reigniting it's engines prior to the landing burn, because the fuel had centrifuged inside the tank due to the spinning)

The concept is interesting, reminds me of the game Stardrive ship design system (although you seem to be going to have crew management)

Banking for turning could have an utility - especially if your spacefighter is turning with it's main engines fired up - it will prevent the pilot from experiencing lateral Gs - which would make piloting quite difficult

well, if the numbers in wikipedia are roughly the good ones for SLS, the core stage + upper stage weight approximately 1000 tons fueled on launch, while the four SSME's gives out around 7440 kN of thrust at sea level. which gives a fueled TWR of around 0.75 for just the core stage + upper stage with no payload. a space shuttle 4-segment SRB weights around 590 tons fueled (91 tons unfueled) - so with the additional segment of the SLS SRB's, we are looking at around 730 tons for each booster. in the end, we are looking at a fueled weight for the full SLS of around 2560 tons - for a 100 tons payload. each srb gives around 16000kN of thrust, + the SSME's we are looking at nearly 40000kN of thrust at liftoff - it gives the fully fueled SLS around 1.5 / 1.6 TWR at liftoff. so no based on the known numbers, the SLS could not liftoff only on it's core stage thrust (even with no upperstage, it would not be able to liftoff, as the upper stage is extremely light compared to the rest of the rocket - the upper stage would only serve for circularization anyway, with it's 30 tons... )

one problem you will have of stacking the core stage, is that the 4 SSME's of the core stage has nowhere near the thrust of the SLS boosters... it's designed to burn a big chunk of it's fuel before the core stage has a positive TWR block I SLS has only 7,4 MN of thrust for the core stage - and 16 MN of thrust per booster you'll have more power by just stacking 3 boosters together than stacking 3 SLS core stages together @canopus the pyrios booster is the planned rocketdyne/dynetics booster with twin F-1B engines - planned to be at least as powerful as the SLS SRB's. (also, they think they can have 20 more tons to LKO with a block II SLS with pyrios than a Block II SLS with SRB's ) and pyrios would be able to be throttled / shutdown in case of problem

my new mobile rotalift launch tower - i don't know if it qualifies, but i built it for the fun of it anyway - the tower is able to drive up and down the slope at the start of the runway (but had to do it carefuly ) the rotalift is powered by SAS modules (once the lift is decoupled from the tower, i can held it in place with the landing legs at the top of the tower). i use landing legs as retractable platforms for my kerbals the spacecraft ended up making a mün landing and return

Bicycle with wings work on earth already http://en.m.wikipedia.org/wiki/MIT_Daedalus

@porkjet - if you are still searching how to integrate an engine inside your mk2 parts, maybe something akin to the X-15 can help you ? With the xlr99 http://en.m.wikipedia.org/wiki/File:North_American_X-15_Nozzle.jpg With twin xlr11 http://s35.photobucket.com/user/DanaC_/media-full//XLR11X15.jpg.html

this was a testbed i built around a variation of the krakendrive, the JD-drive (much more reliable, but less acceleration ) the JD-drive is mounted inside the hull. ended up on laythe with it, after a less than optimal intercept (yeh, understatment here ^^ 8000 m/s of delta-v for a jool intercept, no problems with a krakendrive ) this one supports the activation of the krakendrive in atmosphere (although only when you reach speeds higher than 750 m/s - and the low acceleration might have a hard time in overcoming the drag, so you can use the rapiers in airbreathing mode until the Krakendrive is enough to get you out of atmosphere) - the rapiers also have a bunch of delta-v in rocket mode when you need to do orbital manoeuvers at speeds under 750 m/s. here's the .craft : http://www./view/29ev6dodl38r1x1/JDdrive_SSTO.craft

@nuke, not if the probe is already on a sun orbit, ready to move inside one planet's SOI it should not cost much delta-v to fine-tune a gravity assist. from there, you can modify a lot your orbit if you are in position for multiple gravity assists real life probes have time for them they don't mind if they have to do several assists over the span of several years

well, most of my escape towers end up looking more or less like this although, i use a trick on those : 2 of the topmost separatrons are not using symmetry. they have the same angle, but one of the two is slightly more outside than the other - this gives the escape system a slight assymetric thrust, making the command pod veer away from the rocket without any input (i also disable the command pod torque in the abort sequence, to prevent the SAS from messing with the trajectory ) Launchpad abort test with the assymetric thrust escape tower :

@Woopert - i don't think you need your fuel lines cubic struts are fuel crossfeed capable, and will pump fuel from whatever they are radially attached to (given that the part they are connected to can get fuel from tanks) (although i hope you have enough struts ^^)

Advanced SRBs can be throttled with various means (most discussed above) but also by carefully shaping the srb's solid fuel shape, which will vary the thrust as the fuel burns. (You can find a lot of infos about that here) http://en.m.wikipedia.org/wiki/Solid-fuel_rocket

well, the main problem with real rocket engines, is that their thrust varies with atmospheric pressure Saturn V F-1 engines have 1000kN more thrust in vacuum compared to sea level thrust (6.7MN at sea level) - per engine ! imagine a KSP mainsail lacking 220 kN of thrust at sea level

Well, US air force already signed a cooperative research and devellopment agreement with reaction engines ltd - so the us are already looking into the sabre engine www.reactionengines.co.uk/news_updates.html

Regarding krakensbane activation speed, it seems to be around 700m/s (as seen while playing with krakendrives - they all fail quite spectaculary when we use them to slow down below this speed) - one way to verify if krakensbane code affects your calculations would be to see if you still experience the variation with orbital speeds under 700m/s

@gusturbo it can be used between the various stages (S-IC and S-II middle J2 engine, S-II and S-IVb's j2) and where it's the mostly interesting, between the CSM and the lander (which in turn would allow a perfectly symmetric 4-way fairing separation) so we end up with a rocket with stronger interstages (if you want to include a full interstage ring) and easier to make lander fairing - without single engine fairings in the way

It works with the help of enabled alt+f12 clipping it seems, woopert, if i followed the video correctly. Basically, he attached the decoupler as usual to the engine's node then he attached the fuel tank also to the engine's node, thanks to the alt+f12 clipping. When he removed the tank, the game considers that he removed the part attached to the engine, and thus remove the engine's fairing. This technique can be very interesting for saturn V builders

I don't think squad will work on fairings until they also remake the stock aerodynamics model. (And once the do, they'll surely rework spaceplane parts at the same time )

Well, the parachutes effectiveness is based on their weight. The heavier the parachute, the more it will slow down what's attached to it - all courtesy of the game's drag system which use, among other factors, the weight of a part in the drag formula they use (which is why you only need one xl chute for the 3 man command pod - evrn if it has the same deployed drag than the radial parachute

16th March 2014: SpaceX CRS-3, KickSat, THEIA, TechCube 1, LMRSat, Hermes 2 spaceX CRS-3 launch is also planned to test the Falcon 9 first stage propulsive return capabilities (still due to splash down at the end of the mission) - after the previous test where the fuel had centrifuged inside the tank, preventing reignition just before splashdown. http://en.wikipedia.org/wiki/SpaceX_CRS-3 all in all, it will be a very interesting launch to follow

@ Majorjim having tested the .craft without fairings (the version with the 'ladders' fairings above is built on the .craft gus made avaible in his post) roughly 450 /470 parts for the fairing

Gus, you should try to use the comms DTS-m1 antenna instead of the solar panels it should reduce your fairing part count a bit (and when i tested your rocket with the ladders fairings, your rocket did not need launch clamps it was sturdy enough to rest on it's engines

For the 'density' problem of LH2, they plan to turn it into an asset. The increased size needed will allow Skylon much less aggressive reentrys than a space shuttle. (Skylon's bigger than the space shuttle, yet it's lighter than it when it's fuel tanks are empty) the less agressive reentry profile allows to use much more standard thermal protection than the space shuttle - further decreasing the weight of the system, and the maintenance costs on the thermal protection (although they still use active cooling on leading edges for reentry, thanks to the lh2) Basically, due to skylon being bigger, air drag starts to have a significant effect at higher altitudes than the shuttle. In a jet fuel based system, you would end up having a much more compact system, which will require higher quality TPS to survive reentries.