Update Multistage2026 - Development thread

[Matias Saibene]

I got the impression that the booster particle effects were running on default (minimal/no settings)- very small and no expansion?

I hadn't thought of that, you're right! I need to review the code.

Trying to get the default SLS to launch. I noticed this in the save scn. notice the save stage and alt steps,....
SLS:Multistage2026
STATUS Landed Earth
POS -80.6538895 28.5898809
HEADING 336.00
ALT 57.434
AROT 151.087 -8.198 28.503
ATTACHED 0:0,MS_Hangar
PRPLEVEL 0:1.000000 1:1.000000 2:1.000000
NAVFREQ 0 0 0 0
XPDR 0
CONFIG_FILE Config\Multistage2026\SLS.ini
GUIDANCE_FILE Config\Multistage2026\Guidance\SLS_57302.65_GNC.txt
CONFIGURATION
COMPLEX
HANGAR
CURRENT_BOOSTER 1
CURRENT_STAGE 1
CURRENT_INTERSTAGE 1
CURRENT_PAYLOAD 1
FAIRING
MET -30.000
STAGE_IGNITION_TIME 0.000000
STAGE_STATE
TELEMETRY_FILE Config\Multistage2026\Telemetry\SLS_57310.61_TLM.txt
ALT_STEPS %.1f,%.1f,%.1f,%.1f
PEG_PITCH_LIMIT 35.000
PEG_MC_INTERVAL 0.100
END

There is undoubtedly an error in the formatting of the strings.

I also forgot to mention that Multistage2026 is now, and will be for a while, case-sensitive. It also doesn't accept periods in filenames. I need to fix this as well.

 

[Buck Rogers]

Just to note; I deleted the complex line by testing.

 

[jacquesmomo]

Hi Matias

First of all, my apologies for not giving any news about tests with Multistage 2026.

I've spent a lot of time updating my ELA4 launch site....
Now I'm going to try to make the Ariane 6 flight 267 with my rocket.

I just tried your last module but without really testing it; I only had a quick look.

I'll do a more thorough test soon, but what I can say is:

• the [FX_VENT] section doesn't work
• the [FX_MACH] section doesn't work

There seem to be some issues with the ignition controlled by the guidance file, but I need to test it more thoroughly.

note that I've adapted my Ariane 6 rocket to work with your Multistage 2015 module from October 31, 2025: there are no boosters.
(The rocket's 2 - or 4 - boosters are actually "stages".)
So for the moment I haven't gone any further with my tests...

 

[Matias Saibene]

For now it seems I was able to solve the problems with [FX_VENT] and [FX_MACH].

 

[Matias Saibene]

Guidance is now working!

 

[jacquesmomo]

Guidance is now working!

I think the main issue was the boosters :
only one was working , if you declare more than one.

 

[Matias Saibene]

I think the main issue was the boosters :
only one was working , if you declare more than one.

I'll try to have test releases available today!

 

[Matias Saibene]

Hello Multistage2026 friends!
Sorry for the long pause in Multistage2026 development.

I'm back with a test release.

Guidance, AutoPilot, FX_VENT, and FX_MACH should now be working.


Your feedback is appreciated.

 

[gattispilot]

Thanks. I tried my SLS and she does launch. but not seeing exhaust/thrust from the boosters? and just puffs from the main stage 1

[BOOSTER_1]
N=1
MeshName=SLS_2016\SLSSRB
Height=53.900
Diameter=3.710
EmptyMass=86363.600
FuelMass=622727.300
Thrust=16363630.640
angle=0.000
off=(6.300,0.000,-0.300)
BurnTime=124.000
eng_1=(0.000,0.000,-28.000)
eng_diameter=0.010
ENG_PSTREAM1=srb_exhaust
Speed=(15.000,-4.000,0.000)
Rot_speed=(-0.200,-0.400,0.000)
Eng_tex=
Eng_pstream1=SRB_exhaust
Eng_pstream2=srb_exhaust_2
BurnDelay=0.000
Expbolts_pos=(6.450,0.000,19.000)
Expbolts_pstream=exbolt
Expbolts_anticipation=1.000

 

[Matias Saibene]

Thanks. I tried my SLS and she does launch. but not seeing exhaust/thrust from the boosters? and just puffs from the main stage 1

[BOOSTER_1]
N=1
MeshName=SLS_2016\SLSSRB
Height=53.900
Diameter=3.710
EmptyMass=86363.600
FuelMass=622727.300
Thrust=16363630.640
angle=0.000
off=(6.300,0.000,-0.300)
BurnTime=124.000
eng_1=(0.000,0.000,-28.000)
eng_diameter=0.010
ENG_PSTREAM1=srb_exhaust
Speed=(15.000,-4.000,0.000)
Rot_speed=(-0.200,-0.400,0.000)
Eng_tex=
Eng_pstream1=SRB_exhaust
Eng_pstream2=srb_exhaust_2
BurnDelay=0.000
Expbolts_pos=(6.450,0.000,19.000)
Expbolts_pstream=exbolt
Expbolts_anticipation=1.000

I'm a bit lost in the SLS development thread; where can I download it to try it out?

Thanks in advance.

 

[jacquesmomo]

Thanks, Matias.

I'm trying to find the time tomorow for testing your module with my Ariane 6 rocket.

(I'm also currently building an Ariane 5.)

As soon as I've done some tests, I'll tell you

 

[gattispilot]

My SLS the srb did not separate either. And no thrust visible.
Not sure what this though

 

[Matias Saibene]

My SLS the srb did not separate either. And no thrust visible.
Not sure what this though

Argh! Memory errors again!

Can I try SLS?

 

[gattispilot]

I think it is here?

Addon icon

Space Launch System for Orbiter 2016 0.1.2

Jul 14, 2018

Imported from OHM

• gattispilot
• Spacecraft

Then here is the 2024/26 stuff

 

[Matias Saibene]

I think it is here?

Addon icon

Space Launch System for Orbiter 2016 0.1.2

Jul 14, 2018

Imported from OHM

• gattispilot
• Spacecraft

Then here is the 2024/26 stuff

Thank you so much, it's an amazing add-on, truly magnificent.

I downloaded it and after some adjustments to the scenario, I was able to run it on Linux! Keep in mind that MS2026 is currently case-sensitive, so sometimes it doesn't find .INI files, but .ini files (the same thing but in lowercase) work perfectly!

In this short video, you can see the scenario called "SLS Block 1B (Cargo) Launch Pad.scn" running, which I've attached below so you can see the modified parts.
I'll have to create a guide on adapting/modifying Multistage add-ons when this update is finished.

BEGIN_DESC
<h1>SLS Block 1B Cargo on LC-39B launch pad.</h1>
<p>This scenario begins with MJD 59731, June 6th, 2022.</p>
<br>
<p>Default date of this scenario based on proposed Europa Clipper launch date, i.e. 6th of June 2022 (MJD 59731).</p>
<p>Direct transfer to Jupiter is feasible for Europa Clipper when launched on this day.<p>
<p>Alternatively, one can wait until 17th of June 2022 to launch into heliocentric tranbsit orbits with multiple VILT maneuvers before encounter with Jupiter on 15th Jan. 2030</p>
<p>(See document for more info.)</p>
END_DESC

BEGIN_ENVIRONMENT
  Date MJD 59731
  Help SLS Block 1B Cargo Launch Pad
END_ENVIRONMENT

BEGIN_SHIPS
SLS:Multistage2026
  STATUS Landed Earth
  POS -80.6208910 28.6271778
  HEADING 360.00
  ALT 62.736
  AROT 151.047 -8.224 4.525
  ATTACHED 0:0,MS_LaunchPad_SLS
  AFCMODE 7
  PRPLEVEL 0:1.000000 1:1.000000 2:1.000000 3:1.000000 4:1.000000 5:1.000000 6:1.000000 7:1.000000
  NAVFREQ 0 0 0 0
  XPDR 0
  CONFIG_FILE Config\Multistage2026\SLS_BLOCKIBCARGOTESTNEW.ini
  GUIDANCE_FILE Config\Multistage2026\Guidance\SLS_EM1_Cargo_GNC.txt
  CONFIGURATION 0
  COMPLEX
  CURRENT_BOOSTER 1
  CURRENT_STAGE 1
  CURRENT_INTERSTAGE 1
  CURRENT_PAYLOAD 1
  FAIRING 1
  MET -10.000
  BATTERY 5400.000000
  GROWING_PARTICLES
  STAGE_IGNITION_TIME 0.000000
  STAGE_STATE 1
  TELEMETRY_FILE Config\Multistage2026\Telemetry\SLS_EM1_Orion_GNC.txt
  ALT_STEPS 200.0,350.0,1400.0,35000.0
  PEG_PITCH_LIMIT 35.000
  PEG_MC_INTERVAL 0.100
  RAMP
END
MS_LaunchPad_SLS:EmptyModule
  STATUS Landed Earth
  POS -80.6208910 28.6271778
  HEADING 180.30
  ALT 5.876
  AROT 151.047 -8.224 4.525
  AFCMODE 7
  NAVFREQ 0 0
END
LP39_SLS:SLS_PadA
  STATUS Landed Earth
  POS -80.6208910 28.6267320
  HEADING 270.00
  ALT 1.997
  AROT -180.000 80.621 118.627
  AFCMODE 7
  NAVFREQ 0 0
END
END_SHIPS

 

[gattispilot]

Thanks. so i used that scneario. and get the same thing. no thruster exhaust.
can you send me the whole scn and inis and guidance. My takes offs fast. but I may have tripled the thrust when the booster were not working

 

[jacquesmomo]

Hi Matias

So here are the results of my tests.
For this, I used my Ariane 6 rocket.

Let's assume I'm only mentioning what doesn't work.
The rest works (at least I think so).


[BOOSTER_n] Section

• Eng_tex : ok
• Eng_pstream1 : no smoke

Now we can have multiple boosters (I only tested it with 2, no more)... BUT:
[BOOSTER_1] use Eng_1 Eng_diameter= and Eng_tex= from [BOOSTER_2]
[BOOSTER_2] don't have "Eng_1 Eng_diameter= and Eng_tex=" (no exaust)

No automatic booster separation at the end of combustion
(we must press J for that)
If you press J before the boosters have finished burning, you often (but not always) get a CTD
If you cut off [STAGE_1] engine before, there is no issue


[STAGE_n] Section

• Eng_tex : no exhaust texture
• Eng_pstream1 : no smoke

[PAYLOAD_n] Section
- Payloads are not rendering.
I tried with the following settings :
Render=0 then 1
Live=0 then 1
same result...

[FX_VENT] Section
There is a problem with the operation, but it seems to be related to the guidance file (see below).
The guidance only starts at MET: -4.0 (insted of -70)
I tested it with these values :
Time_fin_1=-10 no working
Time_fin_1=-4 no working
Time_fin_1=-3 ok
Time_fin_1=0 ok

[FX_LAUNCH] section
does not work...


GUIDANCE File :
- The counter starts at MET: -4.0 step:1 instead of MET: -70.0 step:1
(The parameter "-70=orbit(460,465,73)" doesn't work because it's not read at MET: -70
But if I use 10=orbit(460,465,73), then it works.)
- The sound doesn't work
(ex: 71=PlaySound(Sounds\Multistage\A6_267\pilotage calme.wav)

BACKUP file (Current state).scn file
Every time I quit Orbiter and restart (Current state).scn, I get a CTD, whether during flight or even before.
For example, I launch my scenario, then I quit Orbiter.
If I relaunch the (Current state) file, I get a CTD.

Multistage2015_MFD
If I open this MFD, I get the following message:
This Vessel is not a Multistage2015

This is what I have been able to observe so far.

Now I have a suggestion to ask you (I don't know if it's possible):
Multistage2015 and Multistage2026 cannot be used together in Orbiter because the following files have the same name:
boom.dll
EmptyModule.dll
MS_Camera.dll
MS_Crawler.dll
MS_Hangar.dll
stage.dll
Would it be possible to give them another name, for example:
boom2026.dll
EmptyModule2026.dll
MS_Camera2026.dll
MS_Crawler2026.dll
MS_Hangar2026.dll
stage2026.dll

Because - for the moment - I'm using your version of Multistage2015 from October 31, 2025
which works very well, as long as you only declare one booster.

That said, I haven't tested it, but I think these DLL files don't cause any problems and that you can still use either Multistage2015 or Multistage2026 because the names of these two files are different (which is a good idea).

But that's a very minor point.

If I notice any other problems, I'll let you know.
Thanks again for your work...

 

[Matias Saibene]

Thanks. so i used that scneario. and get the same thing. no thruster exhaust.
can you send me the whole scn and inis and guidance. My takes offs fast. but I may have tripled the thrust when the booster were not working

Hi gattispilot!

I've attached the scenario, the config file, and the guidance.
It seems to work on Linux using exhaust, but I haven't tested it on Windows 11 yet. As soon as I finish sending this message, I'll start testing it on Windows 11.

I definitely need to pay more attention to adjusting the .ini reading parameters in the parser. I confess that I'm using ChatGPT to adjust some things when I'm completely stuck; I use it as a last resort. It mainly helps me check that my own clumsiness isn't unintentionally introducing more errors.

Hi Matias

So here are the results of my tests.
For this, I used my Ariane 6 rocket.

Let's assume I'm only mentioning what doesn't work.
The rest works (at least I think so).


[BOOSTER_n] Section

• Eng_tex : ok
• Eng_pstream1 : no smoke

Now we can have multiple boosters (I only tested it with 2, no more)... BUT:
[BOOSTER_1] use Eng_1 Eng_diameter= and Eng_tex= from [BOOSTER_2]
[BOOSTER_2] don't have "Eng_1 Eng_diameter= and Eng_tex=" (no exaust)

No automatic booster separation at the end of combustion
(we must press J for that)
If you press J before the boosters have finished burning, you often (but not always) get a CTD
If you cut off [STAGE_1] engine before, there is no issue


[STAGE_n] Section

• Eng_tex : no exhaust texture
• Eng_pstream1 : no smoke

[PAYLOAD_n] Section
- Payloads are not rendering.
I tried with the following settings :
Render=0 then 1
Live=0 then 1
same result...

[FX_VENT] Section
There is a problem with the operation, but it seems to be related to the guidance file (see below).
The guidance only starts at MET: -4.0 (insted of -70)
I tested it with these values :
Time_fin_1=-10 no working
Time_fin_1=-4 no working
Time_fin_1=-3 ok
Time_fin_1=0 ok

[FX_LAUNCH] section
does not work...


GUIDANCE File :
- The counter starts at MET: -4.0 step:1 instead of MET: -70.0 step:1
(The parameter "-70=orbit(460,465,73)" doesn't work because it's not read at MET: -70
But if I use 10=orbit(460,465,73), then it works.)
- The sound doesn't work
(ex: 71=PlaySound(Sounds\Multistage\A6_267\pilotage calme.wav)

BACKUP file (Current state).scn file
Every time I quit Orbiter and restart (Current state).scn, I get a CTD, whether during flight or even before.
For example, I launch my scenario, then I quit Orbiter.
If I relaunch the (Current state) file, I get a CTD.

Multistage2015_MFD
If I open this MFD, I get the following message:
This Vessel is not a Multistage2015

This is what I have been able to observe so far.

Now I have a suggestion to ask you (I don't know if it's possible):
Multistage2015 and Multistage2026 cannot be used together in Orbiter because the following files have the same name:
boom.dll
EmptyModule.dll
MS_Camera.dll
MS_Crawler.dll
MS_Hangar.dll
stage.dll
Would it be possible to give them another name, for example:
boom2026.dll
EmptyModule2026.dll
MS_Camera2026.dll
MS_Crawler2026.dll
MS_Hangar2026.dll
stage2026.dll

Because - for the moment - I'm using your version of Multistage2015 from October 31, 2025
which works very well, as long as you only declare one booster.

That said, I haven't tested it, but I think these DLL files don't cause any problems and that you can still use either Multistage2015 or Multistage2026 because the names of these two files are different (which is a good idea).

But that's a very minor point.

If I notice any other problems, I'll let you know.
Thanks again for your work...

Thanks for your report. Later, after testing what gattispilot told me, I'll focus on fixing your issue.

Please remember that Multistage2026_MFD is currently unavailable. I'm focusing on fixing the Multistage2026 module first.

 

[jacquesmomo]

Thanks for your report. Later, after testing what gattispilot told me, I'll focus on fixing your issue.

No problem, take your time.
As I was saying, the Multistage version October 31, 2025 works very well for me :
as long as we don't declare more than one booster, I haven't detected any issues with this version.
So this doesn't hinder me in the development of my Ariane rockets.

Please remember that Multistage2026_MFD is currently unavailable. I'm focusing on fixing the Multistage2026 module first.

Yes, that's right, you already mentioned it.

And in my opinion, this MFD isn't a priority; its usefulness is minor.

One last thing, as I wrote in my previous message, the files
boom.dll, EmptyModule.dll, MS_Camera.dll, MS_Crawler.dll, MS_Hangar.dll, and stage.dll,
whether they are dated October 31, 2025, or April 28, 2026, makes no difference :
this simplifies my tests....


@gattispilot or/and Matias

Out of curiosity, I looked at the guidance file included in the SLS_modified_MS2026.zip file.

So I have 3 questions :

1) Does MET start at -10 for you ?
If so, why does mine only start at -4 s instead of -70 ? (may be -70 is too high value ?)

2) With the command
-5.000 =engine(0.00,110.00,5.00,0.00,0.00,0.00)
there are 6 parameters. I only know 3 of them.
Can you explain the other 3 ?

3) With the command
50.000 =fairing(75,0.00,0.00,0.00,0.00,0.00)
there are 6 parameters. I only know 1.
Can you explain the other 5 ?

 

[Matias Saibene]

Thanks. so i used that scneario. and get the same thing. no thruster exhaust.
can you send me the whole scn and inis and guidance. My takes offs fast. but I may have tripled the thrust when the booster were not working

I quickly tested SLS on Windows 11 and it's quite discouraging; I'm getting missing meshes. Back to checking the parser...