Reusable space programme - refuelling and crew return?

[XLjedi]

33 minutes ago, Corona688 said:

1. You didn't attach anything to your ISRU's exposed, spinning, red-hot guts, just glitched them there.  Blowing up the ISRU will expose them hovering on elfin magic.
2. The big ISRU's guts are supposed to be hot.  Attaching cold things to it will stop it from working.
3. Squad didn't implement this restriction in subatomic detail, just barred you from building there at all.

https://kerbalx.com/Corona688/8LMH-Ergrates

It's got lots of room for improvement.  You can get away without RCS or improved reaction wheel, surprisingly, but it's not exactly comfortable to fly.  I'm just afraid to touch it lest I mess up its balance again.

 

Ah...  is that what Squad did?  Good talk!  I'll stow that away for my next ISRU design.  Somehow the radiator manages to work... disconnected and elf-magical though it may be.   I dunno, maybe Squad programmed in some elfin cooling magic.  I s'pose there's lots of magic in the designs nowadays, most of it is elfin auto-strut magic to offset the programming limitations that were first implemented for a rocket-only design program.

Thanks for uploading your craft, I have it in the VAB now...  So you could just rip the fuel cell array off the ISRU on my rover if you like, there's extra fuel cells on the ore container and it doesn't look like you used any fuel cells in your design anyway.  Pretty sure Squad mounted all the little fuel cells on a thick sheet of insulation though, probably why they haven't blow-ded up yet.  Not too concerned about the gear I put near the ISRU, it manages to hold its own on spaceplane re-entry so figure it should continue to survive there OK.    

 

Edited January 22, 2018 by XLjedi

[RizzoTheRat]

7 hours ago, Corona688 said:

1. The big ISRU's guts are supposed to be hot.  Attaching cold things to it will stop it from working

Do radiators work like that?  I thought they operated like a thermostat and let parts heat up to their design temperature before starting to cool?

[Guest]

27 minutes ago, RizzoTheRat said:

Do radiators work like that?  I thought they operated like a thermostat and let parts heat up to their design temperature before starting to cool?

They're on thermostats. I just tested an ISRU/drilling unit and temperatures quickly rose to 1000/500 degrees and 100% thermal efficiency, and then stayed exactly there. If I switched off the radiators they started rising until the system stabilised at a lower thermal efficiency. 

On 19/01/2018 at 5:56 PM, ShadowZone said:

I am also not a huge fan of SSTO spaceplanes. Probably because of the lack of cargo capacity.

Well yeah if your idea of cargo capacity is 1000+ tons then yeah SSTO planes probably won't cut it.

I do routinely loft wide payloads of around 200 tons by plane though.

Edit: about designing for the big ISRU

Here's my current prototype mobile ISRU/drilling platform, with a docked survey rover and the delivery plane in the background. No clipping (other than the wheel mounts which do clip into the fuel tanks but I think you'd have to be pret-ty purist to not allow that.) The radiators and the fuel cell array are surface-attached to the fuel tanks. They do protrude over the ISRU unit but they don't clip, just normal surface attachment. Works well. 

 

Edited January 22, 2018 by Guest

[RizzoTheRat]

3 hours ago, Brikoleur said:

Well yeah if your idea of cargo capacity is 1000+ tons then yeah SSTO planes probably won't cut it.

I do routinely loft wide payloads of around 200 tons by plane though.

To be honest the main reasons I'm not using space planes at the moment are:

1. It takes a long time to reach orbit and recover compared to a VTOL SSTO
2. It takes a lot longer to design and test
3. I'm crap at designing them and really struggle to make something that won't flip on re-rentry
4. I'm crap at flying them.  I have to use MechJeb's Smart A.S.S. to set a pitch attitude as I just can't get on with flying on a keyboard

I have in the past had reasonably success with SSTO planes as fuel tankers, crew shuttles, or for delivering small satellites, but I've never managed anything decent with bigger than Mk2 parts.  But having not played KSP for a while until the last couple of weeks I seem to have completely forgotten everything I learned. 

 

Points 3 and 4 are particularly embarrassing as I have a degree in Aeronautical Engineering and about 8 hours solo in gliders plus several hours P2 in Chipmonks and a Piper Warrior

[Corona688]

9 hours ago, RizzoTheRat said:

Do radiators work like that?  I thought they operated like a thermostat and let parts heat up to their design temperature before starting to cool?

I've overwhelmed ISRU's with too many radiators before, but this is really arguing about nothing since the game won't let you attach to ISRU's guts.  That reasoning is my guess about why.

Edited January 22, 2018 by Corona688

[suicidejunkie]

For fuel sourcing, I like to refine on the surface for faster fueling action.  Pumping mass quantities from one tank to another goes a lot faster than running the ISRU conversion.  The surface bases can mine and refine in the background while I'm off doing other things.

My fuel stations have 2.0 TWR at Minmus surface, and refill on the flats from the refinery tanks before heading back to their posts near LKO and Mun.

For launch vehicles, I usually have them boost the payloads only to space; the payloads can circularize themselves before refueling, which saves on the booster size.

Crew transfers and small cargo ride direct to Minmus surface with a whiplash/nerva Mk2 spaceplane.  I used to do random browser stuff while the planes chugged their way to orbit, but my new PC is a lot faster.

KAS for doing in-situ repairs is also critical to maintaining your fleet and reducing the number of replacements necessary.  Having a collection of common spare parts is much more cost effective than having entire spare vehicles.

[XLjedi]

9 minutes ago, suicidejunkie said:

KAS for doing in-situ repairs is also critical to maintaining your fleet and reducing the number of replacements necessary.  Having a collection of common spare parts is much more cost effective than having entire spare vehicles.

What do you like to keep on hand for spares?

[suicidejunkie]

I've found I've mostly needed midsize engines and landing legs due to terrain/loading glitches.  Smaller fuel tanks and 909s are provided by the junkyard from my early surface-staged rockets.

I do keep a crate at my bases well stocked with lights, screwdrivers, cans of Perri-air (IE; the smallest TAC LS containers), and some RTGs for emergency slapping on to crippled craft to give the engineers time to work.

There's also the standard orbital rescue kit with oscars, ant, octo, parachutes and fins for punting random things (contracts mostly) into Kerbin's air for recovery.

My spaceplanes on the other hand, are generally repaired in the SPH since that's the only place the mirroring can be properly fixed for hands-off ascents.  Jeb was involved when they were officially Kerb-rated for one-wing zero-control reentries / lithobraking, and the more common problem is Minmus nipping off a control surface leading to flat spins on reentry, but I've gotten pretty good at recovering from the latter and putting 'er down on the runway anyways.