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Space Shuttle - Development

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Re: Space Shuttle - Development

Postby Thorsten » Wed Nov 27, 2019 4:07 pm

Okay, it seems I finally have the helium system under control - I've just tested a leak in the center engine reservoir with supplying the center engine from the pneumatic reservoir - works okay till MECO (and triggers the expected warning lights).

The system now has the correct pressure behavior, so only the highest pressure reservoir supplies the interconnect manifold and an engine only draws from the interconnect manifold if its own line pressure is lower than the interconnect manifold pressure (at least that's how I read the valve schematics...)

I suspect (since the helium flow rates are now constant during engine operations) that for long engine use (TAL and RTLS) it may now be required to let the failed engine supply the helium for the others.

I assume there would be cases when two systems fail that make it necessary t manually shutdown a good engine during the late ascent to make sure there's enough helium left - though I've never seen it documented, it would make sense to me..

Currently I assume that we start with 4700 psia and use 3300 psia during a nominal ascent for each engine (which gives some margin till the regulator pressure is underrun...). The pneumatic system is assumed to use 800 psia (so it has enough to compensate for a complete loss of one system).

If anyone has better data, let me know. Also, if anyone has data on how much additional helium the MPS propellant dump would consume - let me know (since the system is now fairly detailed, we can insert all sorts of behavior).

(Oh, and unless you use the property browser you can't try it yet because the 3d work for the switches isn't done yet...)
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Re: Space Shuttle - Development

Postby wlbragg » Wed Nov 27, 2019 6:50 pm

@Wayne: Do you think it is possible to have some attachment points on Hubble to Grapple it and put it back to the bay ?

My plan is to eventually make a Hubble assembly mission. I suppose a disassembly mission, the opposite, would be doable. I need to look at how Thorsten set up the existing capture scenario and should be able to duplicate something of the sorts easy enough. Of course the Hubble is too big to fit in on piece as far as I know. Yet they did put it up in on shot, right? Just need to pack it away in the reverse order it was installed.
The assembly mission is definitely on my long term to do list.

I'm also in the middle of a proper Space Station rendering. I got started on it and the AirCrane grabbed a hold of me again.
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Re: Space Shuttle - Development

Postby Thorsten » Wed Nov 27, 2019 7:04 pm

For normal payloads you'd instance the payload management class and simply define an attachment point, except HST is special, so it has its own management class and the attachment stuff probably has to be copied over.

It *should* be easier to add payloads now, I've done plenty of streamlining.
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Re: Space Shuttle - Development

Postby GinGin » Wed Nov 27, 2019 7:39 pm

My plan is to eventually make a Hubble assembly mission. I suppose a disassembly mission, the opposite, would be doable. I need to look at how Thorsten set up the existing capture scenario and should be able to duplicate something of the sorts easy enough. Of course the Hubble is too big to fit in on piece as far as I know. Yet they did put it up in on shot, right? Just need to pack it away in the reverse order it was installed.
The assembly mission is definitely on my long term to do list.

I'm also in the middle of a proper Space Station rendering. I got started on it and the AirCrane grabbed a hold of me again.


Wow, thanks for that.
That will be a big plus to have a nice ISS



@Thorsten:

Your numbers seem coherent. I hardly found any strong informations about helium consumptions. ( I sent you one relevant doc)
Red lower limit for MPS is 1100 ( engine shutdown) and 3800 for pneumatic system ( left X over valve opened to feed Pneu with left mps helium)

And a lot of cases in ascent pocket checklist for non isolated helium leak, with cross feed and like you said potential engine shutdown.

I guess its gonna be possible now to do a proper propellant purge with center and right interconnect out, left in, and X over valve opened to put all the helium into the feedlines.

Very nice work.
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Re: Space Shuttle - Development

Postby wkitty42 » Wed Nov 27, 2019 8:18 pm

Thorsten wrote in Wed Nov 27, 2019 6:12 am:
i'm consistently getting the following with the latest shuttle dev repo and the latest FG next repo.


That seems to be SRB-separation.

there is some of that... this is a fatal launch from the shuttle landing area... it was working last week and then i foolishly updated my FG from the repos instead of rebuilding what i already had and now i cannot launch at all...

Thorsten wrote in Wed Nov 27, 2019 6:12 am:What are the values of

/ai/models/ballistic[0]/orientation/hdg-deg
/ai/models/ballistic[0]/orientation/pitch-deg
/ai/models/ballistic[0]/orientation/roll-deg

at that point?

no clue as the craft is broken and dragging itself across the landscape upside down at full thrust...

Thorsten wrote in Wed Nov 27, 2019 6:12 am:Also - is this a regression, i.e. does it work for you in older FG versions, or isit characteristic for your setup (I'm not seeing this on any of my setups).

i don't know if it is a regression or not... i think so, though... i'll try to record a video of it...

[EDIT]

i should note that i'm not doing anything fancy... simply loading the shuttle from the launcher by selecting the "ready to launch" one... i am using a config file that specifically disables fuel-freeze since we figured out that was why i could not launch previously... i've made numerous flights to orbit from the KTTS South)Ramp parking area... it is the only place i currently try to launch from... recently i was using the compositor but some problems i was seeing lead me back to using plain ALS and not enabling the compositor at all... i had several good launches after that until the other day when i updated from the repos and now all i can do is blow up on the pad... quite horridly...

[EDIT2]

here's a link to the 1.5 minute video i just made... it is on dropbox but i didn't make it with "dl=1" to show up automatically... you'll have to click it and go from there... it is 29.5MiB in size...
https://www.dropbox.com/s/7mp4bp9jbede7rt/2019-11-27%2017-17-24.mkv?dl=0
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Re: Space Shuttle - Development

Postby wlbragg » Wed Nov 27, 2019 11:09 pm

Oh, and unless you use the property browser you can't try it yet because the 3d work for the switches isn't done yet...)

Switch animations are now pushed to dev branch.
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Re: Space Shuttle - Development

Postby GinGin » Thu Nov 28, 2019 5:39 pm

As we are in Helium, can we have the body flaps push button that extinguishes at the end of the prop dump ? :)


Thanks Wayne!
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Re: Space Shuttle - Development

Postby Necolatis » Thu Nov 28, 2019 11:56 pm

Don't know if you are aware or already are using stuff from them, but I found a GPL 2.0 project (NASSP) that has lots of (untextured but nice) models of Cape Canaveral's launch complex. (Apollo era)
They are not AC3D but easy to convert (I tried a couple). Maybe they just need small adjustments to pass for shuttle complex.

There is the crawler and other stuff in there:

Code: Select all
Apollo_2chute                       LTA_2R
Apollo_3chute                       milkstandext
Apollo_3chuteEX                     nAstp2
Apollo_3chuteHD                     nAstp3
apollo8_lta                         nsat1aerocap
ApolloLC39_MSS                      nsat1intstg
BoostCover                          nsat1stg1
CanaveralLC34LUT                    nsat1stg2
CanaveralLC34MSS                    nsat1stg21
CanaveralLC34Pad                    nsat1stg22
CanaveralLC37                       nsat1stg23
CanaveralLC39                       nsat1stg24
CanaveralLC39A                      Rocks
CanaveralRoad                       sat_target
CanaveralRoad4                      sat5AstroS
CM                                  sat5Flag
CM-ApexCover                        sat5intstg
CMB                                 sat5intstg4
CM-Balloons                         sat5intstg8
CMB-ApexCover                       sat5sky1
CMB-HatchC                          sat5sky2
CMB-HatchO                          sat5skylab
CMB-Recov                           sat5skylablaunch
CM-CMP                              sat5stg1
CM-CMPEVA                           sat5stg2
CM-CREW                             sat5stg2base
CM-CrewRecovery                     sat5stg2intstg
CM-HatchC                           sat5stg3
CM-HatchO                           sat5stg31
CM-Interior                         sat5stg32
CM-OpticsCover                      sat5stg33
CM-Probe                            sat5stg34
CM-ProbeExtended                    sat5stg3base
CM-Recov                            sat5stg3intstg
CM-VC                               Saturn1bML
Crawler_centerpanel                 Saturn5ML
Crawler_centerpanel.static          Saturn5ML.static
Crawler_centerpanel_reverse         Saturn5MLPedestals
Crawler_centerpanel_reverse.static  SM
Crawler_drivetrucks                 SM-core
Crawler_Mainbody                    SM-CRYO
FraMauro1                           SM-HGA
FraMauro2                           SM-Panel1
KSCCrawlerway1                      SM-Panel2
KSCCrawlerway2                      SM-Panel3
KSCCrawlerway3                      SM-Panel4
littlejoe                           SM-Panel5
littlejoelauncher                   SM-Panel6
LM_1                                SM-RCS
LM_ascent                           SM-RCSHI
LM_ascent2                          SM-RCSLO
LM_ContactProbes                    SM-SIMBAY
LM_Descent                          SM-SPS
LM_Landed                           SM-SPSTanks
LM_NoWheel                          SubSatellite
LM_Parked                           VAB_exterior
LM_SLA                              VAB_exterior.static
LRV                                 VAB_interior
LRV_console
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Re: Space Shuttle - Development

Postby GinGin » Fri Nov 29, 2019 6:59 am

Interesting, in which version did you looked ?
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Re: Space Shuttle - Development

Postby Necolatis » Fri Nov 29, 2019 7:09 am

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Re: Space Shuttle - Development

Postby Thorsten » Sat Nov 30, 2019 5:53 pm

We should have the BF indicator signal the end of MPS dump now - I haven't tested whether it switches correctly back to the normal function during a normal entry, and I still have to add it to the RTLS and contingency MECO conditions, so don't report oddities just yet...
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Re: Space Shuttle - Development

Postby GinGin » Wed Dec 04, 2019 7:38 am

Very nice.
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Re: Space Shuttle - Development

Postby Gomendio » Thu Dec 05, 2019 12:43 pm

Hi there guys.

To put some light into the issue then. I deleted the 2019.1 after suffering major bugs and correct me if I'am wrong.

The rolling back into the 2018.3 assures the proper functioning of the latest dev version shuttle in all the scenarios right? Launch orbit de-orbit taem...
No more crashes..over G when panning through the external views and so on.

Is there a major change in graphic quality and overall control between the 18.3 and the 2019.1? The Earthview 8k High res could be modded as well into
this version?

And the last one. The troubleshooting with the 2019.1 is expected to be extensive and complicated?
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Re: Space Shuttle - Development

Postby Thorsten » Thu Dec 05, 2019 2:26 pm

Since we don't exactly know what we're dealing with, there are no certainties.

The facts of the matter are that both GinGin and I have tested the Shuttle a lot on 2018.3 and seen no major issues - eatdirt has done long-duration missions with FG on for a day or longer. So as far as test data goes, that's quite good.

If what you've seen is not 'yet another thing', then you should see the same.

There's no loss on rendering quality by reverting to the previous FG version I would know of, in particular Earthview works just the same.

The troubleshooting with the 2019.1 is expected to be extensive and complicated?


That sounds about it.
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Re: Space Shuttle - Development

Postby Gomendio » Fri Dec 06, 2019 6:12 pm

Many thanks thorsten :wink:
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