totm june 2018 Work-in-Progress [WIP] Design Thread

[Darth Lazarus]

26 minutes ago, Temstar said:

ZOMG reusable booster, I'm making one as well but using wings.

How do you setup the parachute landing so it lands so horizontally? I tried to do parachute horizontal landing but it's very difficult to get the CoL and CoM match up. Is it just trial and error?

You know what your system reminds me of? The MTKVP: https://falsesteps.wordpress.com/2012/10/06/mtkvp-glushkos-opening-gambit/

lot's and lot's of trial and error. first i try to find the dry mass of the booster, then i place the chutes ... and then testing ...
and i had something more like this in mind:

http://www.buran.fr/energia/img/blocA-en.jpg

[Temstar]

25 minutes ago, Darth Lazarus said:

lot's and lot's of trial and error. first i try to find the dry mass of the booster, then i place the chutes ... and then testing ...
and i had something more like this in mind:

http://www.buran.fr/energia/img/blocA-en.jpg

That's a reusable Zenit right?

My own attempt at horizontal landing was focused on splashdown which meant it had to land very horizontal and below 6m/s. I couldn't get that to work. You inspired me to have another go with your system.

The Zenit diagram is shown with landing legs. Is there any advantage to using landing gear in ksp over landing legs?

[Darth Lazarus]

29 minutes ago, Temstar said:

That's a reusable Zenit right?

My own attempt at horizontal landing was focused on splashdown which meant it had to land very horizontal and below 6m/s. I couldn't get that to work. You inspired me to have another go with your system.

The Zenit diagram is shown with landing legs. Is there any advantage to using landing gear in ksp over landing legs?

yup, reusable zenit booster for my Energia M

there is a very big difference in impact tolerance. landing legs have a tolerance of about 10 m/s, landing gear has 50 m/s (lol). and the landing gear looks way better then the normal legs.

[Rune]

8 hours ago, Temstar said:

ZOMG reusable booster, I'm making one as well but using wings.

How do you setup the parachute landing so it lands so horizontally? I tried to do parachute horizontal landing but it's very difficult to get the CoL and CoM match up. Is it just trial and error?

You know what your system reminds me of? The MTKVP: https://falsesteps.wordpress.com/2012/10/06/mtkvp-glushkos-opening-gambit/

I'd imagine he checks CoM with the empty tanks, then places the chutes symmetrically around it. It seems we will soon see a Buran with the reusable boosters the real thing never had. Yup, I totally called it right, but a tad too late as it seems I was working with a page 8h old (Firefox is cool saving me bandwidth, but sometimes it does a bit too much). As to your booster concept, I saw it and thought "I should have thought of it myself". Oh, and that blog you linked, I have to investigate it further...

 

Rune. Surprisingly enough, in KSP, wings may end up weighting less than chutes, or surprisingly close. 1xBigS delta = 5x Radial chutes

Edited December 24, 2015 by Rune

[Darth Lazarus]

nearly fnished the work on the reusable boosters. Energia M ready for lift-off

[pTrevTrevs]

Soon

[sgt_flyer]

i managed to find a way to fire SRB's from within a hull made of stock fairings - so now i can build custom size stock SRB's (can't fire the engine while stowed be damned ^^)

here it is custom sized SRB ^^ - around 2m in diameter, with only the skirt extending to 2.5m (also, thanks to the skirt, i could place the kickbacks higher up within the 'hull' - so the SRB's COM is further upwards within the SRB)

the winged ET is just something i thrown together fast so i could test if the separation sequence worked correctly ^^)

 

basically, there's multiple sets of fairings that make up the SRB's skin - each one covering less than half of the kickbacks (else the 'stowed in' thing pops up). i combined that with my technique to create open ended fairings at the lower end, so the kickbacks thrust can exit the fairing - yup, all stock 78 parts for each SRB, with all the nose cone assembly + the separatrons which account for a whole lot of parts :p)

- those currently house 7 kickbacks each. (though, those kickbacks could reaallly use an increase in thrust :p)

 

 

 

 

one small problem though, is that the custom nose i built out of radiator panels in order to house the parachutes tends to heat a bit during ascent ^^ (besides, while the booster survives intact a 7m/s landing on ground, it despises water and ruds upon splashing down ^^)

 

 

so if you need to place an order of custom SRB's for your own shuttles, feel free to ask ^^

Edited December 27, 2015 by sgt_flyer

[Temstar]

Hmmmm, how does that winged ET fly? Can it safely re-enter and land at KSC?

[sgt_flyer]

@Temstar

 

This winged ET can go into a flat spin easily at low speeds (especially if you stray a bit too far from the prograde marker (more than 25° / 30°) - could use some dihedral angle for the wings

though, i had roughly 25% fuel left, i could recover from the spin by firing the engine.

^^ - other than that, it can survive reentry from a 100km orbit, with an agressive reentry deorbit burn (from above the desert's mountain, 145m/s deorbit burn, the suborbital line drops in the ocean a bit after KSC - so pretty agressive, the nose and the tanks heat up a bit)

though, it still needs an AoA of 30 /40° above the horizon to bleed off speed at high altitudes) - still, even without tweaks to the lifting body it seemed to be able to fly a bit better than a winged brick (i have large flat structural wings between the main wings)

Edited December 27, 2015 by sgt_flyer

[Temstar]

I may have to steal that winged ET idea for a Block III version of my reusable lifter @sgt_flyer


In other news, after much tedious trial and error I got parachute recovery ET tank worked out, thanks to @Darth Lazarus and this thread for the inspiration.

Edited December 27, 2015 by Temstar

[Majorjim!]

8 hours ago, sgt_flyer said:

Snip

Hmmm. How many fairings per stack?

Edited December 27, 2015 by Majorjim

[sgt_flyer]

@Majorjim

the current version use 4x 1.25m fairings per booster (might be feasible with 3, but using 2 won't work (one of the two would trigger the stowed status) - of course, if i remove the parachute assembly and only add a 1,25m nosecone (for the separatrons) it would lower drastically the overall part count. (without the chutes, the radiators section (made of 36 radiators) could be replaced by stretching further the topmost fairing. in addition, we could remove all the parachutes (and the parts used to radially attach them) and decouplers, plus the probe core and batteries.

i'll try to create a post about it in the open source construction techniques thread

Edited December 27, 2015 by sgt_flyer

[Majorjim!]

Just now, sgt_flyer said:

@Majorjim

the current version use 4x 1.25m fairings per booster (might be feasible with 3, but using 2 won't work (one of the two would trigger the stowed status) - of course, if i remove the parachute assembly and only add a 1,25m nosecone (for the separatrons) it would lower drastically the overall part count. (without the chutes, the radiators section (made of 36 radiators) could be replaced by stretching further the topmost fairing. in addition, we could remove all the parachutes (and the parts used to radially attach them) and decouplers, plus the probe core and batteries.

i'll try to create a post about it in the open source construction techniques thread

It looks ok I just hate the fairings with a passion. I will stick to using a bundle of just SRBs for my shuttle. I will use a fairing for the ET though. For the right diameter tank.

 Also that's eight long fairings. How much do they all weigh?

Edited December 27, 2015 by Majorjim

[Mad Rocket Scientist]

[sgt_flyer]

@Majorjim

the 4x fairings weight 2.7 tons. (3.2 tons if you add the empty 1.25m to 2.5 C7 adapter i used at the bottom - though like the topmost nosecone, i use it to support the separatrons - so they aren't 'stowed' within fairings) - so you're looking at around 3.3 / 3.4 tons per booster for the full body work (if not using parachutes)

Edited December 27, 2015 by sgt_flyer

[Mad Rocket Scientist]

SpaceX style reusability:

[Mad Rocket Scientist]

Feedback greatly appreciated:

[Mad Rocket Scientist]

[Mad Rocket Scientist]

/me hates fairing based command pods with a purple passion

[Mad Rocket Scientist]

Alright, what should I do here:

Any position of any engine that doesn't get the stowed message ruins the look of it.  So here's my choices:

A. Ruin it.  Form over function.  Engines will show.
B. Rebuild it.  Rebuild the engine nacelle so that engines can fit.  Won't look as good, and will be annoying to rebuild again, but could possibly look better than ruining it.
C. Screw it.  Rebuild the entire capsule with that fuel tank.  Loses some overall looks and interior, but probably best option for non-cheaty good-looking engine nacelles.
D. Cheat it.  Stuff bigger engines somewhere where they won't show.  Not sure where this is, so that may not work, and you would see a engine plume.

What should I do?

[sgt_flyer]

@Mad Rocket Scientist

yeh, you need to make the engines just more than half outside the 'stowed' zone - but that can be hard to do, as it often does not exactly match the shape of the fairing... (i think it's because they are calculated out of spheres) - i managed to do it for my soyuz descent module's separatron retrorockets, but they are placed just nearby the seam between two fairings. (the 'seam' has the same diameter on each because i copied the fairing, then edited them to create each section's shape  - but in your case with a custom inside, might not be feasible.

possibility you might be able to use the long structural intakes to both create the shape and have something you can surface attach your 24-77 onto

[Majorjim!]

4 hours ago, sgt_flyer said:

@Majorjim

the 4x fairings weight 2.7 tons. (3.2 tons if you add the empty 1.25m to 2.5 C7 adapter i used at the bottom - though like the topmost nosecone, i use it to support the separatrons - so they aren't 'stowed' within fairings) - so you're looking at around 3.3 / 3.4 tons per booster for the full body work (if not using parachutes)

OK, that's not too bad weight wise. I think I would want more than 8 SRBs though. We really need a larger size SRB..

[Mad Rocket Scientist]

6 minutes ago, sgt_flyer said:

@Mad Rocket Scientist

yeh, you need to make the engines just more than half outside the 'stowed' zone - but that can be hard to do, as it often does not exactly match the shape of the fairing... (i think it's because they are calculated out of spheres) - i managed to do it for my soyuz descent module's separatron retrorockets, but they are placed just nearby the seam between two fairings. (the 'seam' has the same diameter on each because i copied the fairing, then edited them to create each section's shape  - but in your case with a custom inside, might not be feasible.

possibility you might be able to use the long structural intakes to both create the shape and have something you can surface attach your 24-77 onto

I've tried to get the engines outside the fairing, but even when it looks more than halfway out it still doesn't fire.

I don't think that will work with an interior, so that won't work.

I've already tried, and they're too long.

[sgt_flyer]

@Majorjim

well, they are all centered anyway, so the plume doesn't spill on the sides, and the exhaust can get out of the open ended fairing - i built a simpler version without parachutes, and i added 12 Kickbacks onto the initial one  although, even like this, those kickbacks are soo lacking in twr that you might need to lower the fuel...

with 13 kickbacks the booster alone had something like 2,5 TWR @ sea level...

[Majorjim!]

3 hours ago, Mad Rocket Scientist said:

Feedback greatly appreciated:

Looks lots of fun to fly! I assume its a WIP so I wont mention strut tidying.

Just now, sgt_flyer said:

@Majorjim

well, they are all centered anyway, so the plume doesn't spill on the sides, and the exhaust can get out of the open ended fairing - i built a simpler version without parachutes, and i added 12 Kickbacks onto the initial one  although, even like this, those kickbacks are soo lacking in twr that you might need to lower the fuel...

with 13 kickbacks the booster alone had something like 2,5 TWR @ sea level...

Damn... They are so underpowered compared to what we need them for. Ho hum, we can but hope.