# OFSS IV-pilot roll call

#### kamaz

##### Unicorn hunter
If you are free to fly now, I will post the scenario right away on this thread.
Please do. I should be able to fly it on Saturday at the latest.

#### Castor

##### New member
Okay, kamaz and ADSWNJ, here is the scenario for the first flight. It will be later included in the flight package:

Code:
BEGIN_DESC
Themis-A is primed for launch at T-100 seconds.
Launch MFD has already been set up for the correct orbit.
Good luck!
END_DESC

BEGIN_ENVIRONMENT
System Sol
Date MJD 60219.7711306855
END_ENVIRONMENT

BEGIN_FOCUS
Ship Themis-A
END_FOCUS

BEGIN_CAMERA
TARGET Themis-A
MODE Cockpit
FOV 30.00
END_CAMERA

BEGIN_HUD
TYPE Surface
END_HUD

BEGIN_MFD Left
TYPE User
MODE Themis Control
END_MFD

BEGIN_MFD Right
TYPE User
MODE LaunchMFD
BOOLALT 0
BOOLENG 0
HOV 0
BOOLLNC 0
BOOLTGT 1
BOOLHUD 1
BOOLPTC 1
BOOLCOR 1
BOOLDAS 0
BOOLLOWINC 0
GCCONT 0
ALOCK 0
PVIEW 0
INCL 1.12
IFACT 0.50
AFACT 10.00
PEA 219990.98
APA 219990.98
GCSTEP 10.00
TGT LaunchMFD-Probe-Themis-A
TGTDISP 64>105q
END_MFD

BEGIN_SHIPS
loco01:SaganSpaceport\\loco01
STATUS Landed Earth
POS 169.5332697 -0.8578510
AFCMODE 7
NAVFREQ 0 0
Angle 0.00
SpeedT 0
SpeedC 0
END
Crane:SaganSpaceport\\XR5_Crane
STATUS Landed Earth
POS 169.5270000 -0.8542000
AFCMODE 7
NAVFREQ 0 0
X_P 0.50
Y_P 0.00
Z_P 0.50
X_T 0.50
Y_T 0.00
Z_T 0.50
END
STATUS Landed Earth
POS 169.5375920 -0.8578510
AFCMODE 7
PRPLEVEL 0:1.000000
NAVFREQ 0 0
Arms_P -0.000137
Arms_T 0.000000
Lights 0
END
STATUS Landed Earth
POS 169.5330990 -0.8597000
AFCMODE 7
NAVFREQ 0 0
END
STATUS Landed Earth
POS 169.5321950 -0.8686880
AFCMODE 7
PRPLEVEL 0:1.000000
NAVFREQ 0 0
Lights 0
Config -1
END
OFSS:IMS\Command_Modules\BM201_CONTROL_MODULE
STATUS Landed Earth
POS -95.7481615 1.3305911
ATTACHED 3:0,Themis-A
AFCMODE 7
PRPLEVEL 0:1.000000 1:1.000000 2:1.000000
NAVFREQ 0 0
COMMAND 0 1
TDPOINT 0,0,0 0,0,0 0,0,0
EMPTYMASS 10000.000000
MASSCENTER 0.000000 0.000000 0.000000
PMI 8.150000 8.150000 2.300000
CONSUMABLES 0.0001 0.0001 0 0.0001 0.0001 0 0.0001 0.0001 0
TEMPERATURES -1:298.00:273.91
HEATING -1
THGROUPLEVELS 0 0 0 0
CREW 2 0
ENERGY 396000000.000000
MFC 0 0 0 -1 -1 -1 -1
MFC 0 0 0 -1 -1 -1 -1
MFC 0 0 0 -1 -1 -1 -1
MFC 0 0 0 -1 -1 -1 -1
MFC 0 0 0 -1 -1 -1 -1
MFC 0 0 0 -1 -1 -1 -1
MFC 0 0 0 -1 -1 -1 -1
MFC 0 0 0 -1 -1 -1 -1
MFC 0 0 0 -1 -1 -1 -1
MFC 0 0 0 -1 -1 -1 -1
MFC 0 0 0 -1 -1 -1 -1
MFC 0 0 0 -1 -1 -1 -1
MFC 0 0 0 -1 -1 -1 -1
MFC 0 0 0 -1 -1 -1 -1
END
Themis-A:Themis-A\Themis_5x8
STATUS Landed Earth
POS 169.5375920 -0.8578510
AFCMODE 7
PRPLEVEL 0:1.000000 1:1.000000 2:1.000000 3:1.000000
NAVFREQ 0 0
PL_DESCRIPTION OFSS 0.000 0.000 27.000 -0.0000 -0.0000 -1.0000 0.0000 1.0000 0.0000 0
IN_JETTISON 0 0
J_MARKER 0.000000
FC_Config 250000.035285 90.000016 0 0 44.100000
FC_State 0 0.000000 0.000000
LV_State 1 1 1 1 0.000000 1
LV_Config 2 1 1
END
LaunchMFD-Probe-Themis-A:LaunchMFD-Probe
STATUS Orbiting Earth
RPOS -2870250.93 962552.54 6337780.71
RVEL -1841.726 7049.499 -1902.258
AROT 0.00 -0.00 0.00
AFCMODE 7
NAVFREQ 0 0
END
END_SHIPS

BEGIN_uap
END

---------- Post added at 08:48 AM ---------- Previous post was at 08:33 AM ----------

Date of completion for first mission: May 27 (Tuesday)
Date of launch of second mission: May 30 (Friday)

ADSWNJ, please confirm that you will be acting backup for the first mission, and also post if you are ready to go ahead with the second mission on May 30.

---------- Post added at 09:37 AM ---------- Previous post was at 08:48 AM ----------

One more thing: don't forget to check out the new IMS RC9

#### Loru

##### Moderator
Donator
Are you planning to fly Themis manually, using it's AP or LaunchMFD autopilot? I'm not sure it'll work with LaunchMFD autopilot (It uses thrust vector control instead of regular RCS for first stage ascent)

#### Castor

##### New member
Are you planning to fly Themis manually, using it's AP or LaunchMFD autopilot?
I think that kamaz will also use the Themis's default AP. Personally, in all my test flights, I used the default AP, which is why I have set the left MFD to Themis Control in the scenario.

#### kamaz

##### Unicorn hunter
LaunchMFD to calculate heading, Themis AP to fly.

#### Castor

##### New member
The OFSS III subforum has been renamed to OFSS, so that all discussions (with regard to OFSS) can continue to take place within this subforum.

#### kamaz

##### Unicorn hunter
Pre-flight check failed:

Code:
>>> ERROR: No vessel class configuration file found for:
---------------------------------------------------------------
>>> ERROR: Themis-A\Themis_5x8
>>> [Vessel::OpenConfigFile | .\Vessel.cpp | 252]
---------------------------------------------------------------
>>> TERMINATING <<<
...can I have your Config\Vessels\Themis-A\Themis_5x8.cfg ?

#### garyw

Tutorial Publisher
Can you not use the configuration tool to re-generate that config?

#### kamaz

##### Unicorn hunter
(a) because 5x8 is fairing type, it tells me nothing about the number of SRBs and the upper stage type
(b) to let Castor know that the official mission kit should include this file

Also, I only got the error after I edited the .scn and switched BM201 to non-IMS version -- with the scenario as posted, Orbiter was simply crashing.

Of course I could have simply said that "Orbiter is crashing with nothing of interest in the log file", but that would not be helpful, would it...

---------- Post added at 09:58 PM ---------- Previous post was at 07:54 PM ----------

Um. Using Themis-A editor, I've made the missing file like that:

Code:
; === Configuration file for vessel class 'Themis-A' ===
ClassName = ThemisA
Module = Themis-A\Themis-A_Core
EditorModule=Themis-A\Themis-A_Core

;Fairing configuration
Fairing = 2

;Decides 2nd stage configuration
Upperstage = 2

;Boosters configuration
Boosters = 0

;Configures offset above ground
Offset = 0
...and Orbiter now crashes with an utterly unhelpful log file

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#### Castor

##### New member
I am extremely sorry. Copy the config file below and rename it as Themis_5x8.cfg.

Code:
; === Configuration file for vessel class 'Themis-A' ===
ClassName = ThemisA
Module = Themis-A\Themis-A_Core
EditorModule=Themis-A\Themis-A_Core

;Fairing configuration
Fairing = 2

;Decides 2nd stage configuration
Upperstage = 2

;Boosters configuration
Boosters = 6

;Configures offset above ground
Offset = 0

---------- Post added at 03:36 AM ---------- Previous post was at 02:52 AM ----------

Never mind, I have included a release with the required config files and scenarios. Just download that from the first post of this thread (no documentation yet).

#### Pipcard

##### mikusingularity
Donator
(apologies if you think I'm ripping off kamaz here. I want to do an in-character business letter, too)

Dear Mr. Castor,

As Hatsunia's commercial launch service provider, Hatsunespace is seeking to launch the Tranzit orbital tug with the M-II Heavy rocket for the OFSS IV program's fifth mission. The M-II Heavy has a maximum lift capacity of 32,700 kg to low Earth orbit, but it will be less for an 800 km orbit with 64° equatorial inclination. On its own, the Tranzit has a total mass of 33,000 kg at lift-off and a delta-v budget of about 4 km/s. Because of that, we are confident that it (with slightly less fuel) can be launched on the M-IIH from Negishima Space Center in order to rendezvous with the station.

Once the M-II's high-energy upper stage has delivered the Tranzit to an apoapsis of approximately 800 km, it will still have plenty of fuel left over to dock with the station and support its construction. On each of the sixth and eighth missions, the Tranzit can rendezvous with the modules carried by the Smerch or DM-2 tugs and ferry them, all at once, back to the station in order to save time and fuel.

However, we will have to develop a larger payload fairing (over 6 meters in diameter) in order to accommodate the vehicle.​

Sincerely,

Satoshi Nasuda
Hatsunespace CEO​

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#### kamaz

##### Unicorn hunter
Um... it crashes again.

Some quick investigation shows that the crash is caused by IMS -- i.e. if I edit the scenario to replace BM210 with non-IMS version, then the scenario loads fine. I have reinstalled IMS RC9, but it did not help.

...Worst case I'll cheat by flying the mission with a normal BM210

---------- Post added at 08:43 AM ---------- Previous post was at 08:41 AM ----------

(apologies if you think I'm ripping off kamaz here. I want to do an in-character business letter, too)
Oh, it's sweet. I think we could have more of these

#### Pipcard

##### mikusingularity
Donator
Don't forget to post screenshots!

#### Castor

##### New member
In order to try and replicate your problem, I installed the addons one by one in a fresh Orbiter installation, but I didn't get a crash. Didn't install the XR2 and the XR5 though. My internet connection has been quite slow for the past few days, but anyway I am uploading that Orbiter installation to my dropbox and will PM you the link as soon as it is done.

On its own, the Tranzit has a total mass of 33,000 kg at lift-off and a delta-v budget of about 4 km/s. Because of that, we are confident that it (with slightly less fuel) can be launched on the M-IIH from Negishima Space Center in order to rendezvous with the station.

Once the M-II's high-energy upper stage has delivered the Tranzit to an apoapsis of approximately 800 km, it will still have plenty of fuel left over to dock with the station and support its construction. On each of the sixth and eighth missions, the Tranzit can rendezvous with the modules carried by the Smerch or DM-2 tugs and ferry them, all at once, back to the station in order to save time and fuel.
The Tranzit requires about 10% of its fuel just to deorbit. As dictated by safety rules, each tugging must be allotted at least 15% fuel and a reserve of 10%. Since we have two tugs, that makes it 50%. Adding the quantity required to deorbit, makes 60%. Finally, in case of some error in the initial rendezvous procedure, corrections may require 5%.

In short, the Tranzit must be fueled somewhere between 65% and 70%, which translates to a mass of 24900 kg to 26100 kg. Will that weight reduction be sufficient for M-II to deliver the Tranzit to within 50km of the station ?

#### Pipcard

##### mikusingularity
Donator

Dear Mr. Castor,

Hatsunespace has recently conducted launch trajectory analysis simulations and has determined that the M-II Heavy is able to launch the Tranzit with 75% of its maximum propellant load to an orbit with an inclination of 64°, an apoapsis of 800 km, and a periapsis of 200 km. Our analysis takes into account the more massive fairing required to encapsulate the payload. The payload itself will have a mass of 27,300 kg at launch, and a delta-v of 3486 m/s. We have also found out that the delta-v required to change an 800x200 km orbit to an 800x800 km circular orbit is only about 167 m/s. This is about 4-5% of the total delta-v budget allotted.​

Sincerely,

Satoshi Nasuda
Hatsunespace CEO​

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#### Castor

##### New member
Hatsunespace has recently conducted launch trajectory analysis simulations and has determined that the M-II Heavy is able to launch the Tranzit with 75% of its maximum propellant load to an orbit with an inclination of 64°, an apoapsis of 800 km, and a periapsis of 200 km. Our analysis takes into account the more massive fairing required to encapsulate the payload. The payload itself will have a mass of 27,300 kg at launch, and a delta-v of 3486 m/s. We have also found out that the delta-v required to change an 800x200 km orbit to an 800x800 km circular orbit is only about 167 m/s. This is about 4-5% of the total delta-v budget allotted.
All proposals accepted.

---------- Post added at 03:39 AM ---------- Previous post was at 03:00 AM ----------

Since OFSS can be not only a fun endeavor for those experienced in Orbiter, it could also be a teaching experience for the newbies. So, I'm going to propose that the documentation will not cover mission specific details, but instead they will be discussed here on the forum. So, I would like to know what the current pilots feel about this idea.

#### mojoey

##### Bwoah
I think it'd be prudent to include a somewhat vague mission-by-mission guide, in case for whatever reason they can't find this thread. Sort of a: 'Take this bit off, and put this other bit where that bit was, then put the original bit on top of the new bit' thing.

#### Pipcard

##### mikusingularity
Donator
Did a practice run (with non-spherical gravity turned on), starting with a scenario with these conditions:
-the ISS (with CMG) in a 800 x 800 km orbit
-the Tranzit in a 800 x 200 km orbit, planes already aligned with the ISS

I managed to rendezvous and dock with the station using 206 m/s of delta-v.

Sync orbits with non-spherical gravity isn't as bad as I thought it was going to be. All I needed were small corrections to the DTmin whenever I passed the intercept point.

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#### Castor

##### New member
ADSWNJ, please confirm that you will be available for the second launch.

If any of the other enrolled pilots are interested in acting backup for this mission, please speak up.

Enrolled or otherwise, all pilots on this forum are free to take up mission 3.

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