Question XR Series - Possible to load empty module to fill later?

[EndeavourCmdr]

Here is the thing. I'm planing some interesting trips with the XR, and I don't actually want to take all of the LOX up with me from Earth. Instead what I'd like to do is bring just the empty LOX containers up with me, and then fill them once I reach one of my "layover stops" along the way to the outer planets.

I attempted to load the XR2 up with an empty LOX container, but when trying to load it, nothing happened. Upon reading the comments in the config file for this payload, I see the reason justified as the LOX container has exceeded its lifetime and can no longer be filled.

Is it possible to maybe adjust the way that the config file and code works Doug so that we could have a "default loadout" and "max loadout" setting so that say, by default a payload would be loaded with <default loadout> when it's added using the payload manager, but that it could then be filled to <max loadout> amount of either LOX / Scram Fuel or Main Fuel later (obviously scram would be a bit of an exception since it can only be filled on Earth)?

This would be very much appreciated, and I can't imagine that it would be very hard to implement on your end.

Thanks in advance.

 

[Cras]

I am not sure I understand the problem here, because from what I read, you want to put and empty module into the cargo bay, and then fill it while it is in the ship.

If that is the question, then you can, because I do it all the time. I re-use the fuel tanks and scram tanks and a LOX tank. I have them all laying around KSC, empty. When it is time to go on a trip, I am able to load them into the cargo bay of the XR-2, and then load them up with fuel, or oxygen, no problem.

I dont get this "exceeded its lifetime" thing you are talking about.

 

[EndeavourCmdr]

Hmm maybe thats the thing is that you have them laying around KSC empty. I'm talking about when you load an XR2 LOX module using the payload manager, for example. It's already full. There is an option to select LOX - Half or LOX - Empty, but those two options aren't about quantity in the tank, more like, max capacity half and max capacity 0.

 

[Cras]

Could be. I added them to the scenario via the scenario editor, because I wanted to name it a certain way, I didnt want it in the ship just yet, and I wanted them empty and not filled magically from the start, I wanted to fill them when in the ship, because it is not often I fly with the tanks full.

 

[EndeavourCmdr]

Right exactly same here, and I was wondering if maybe it might be possible to load empty modules the same way using the built in XR payload manager.

 

[dgatsoulis]

It is very easy to make one for yourself. Go to the Orbiter\Config\Vessels directory and make a copy of the XR2PayloadMainFuel file.
Rename the copy to XR2PayloadEmptyMainFuel and open it with an editor (notepad).
Change these lines:
ClassName = XR2PayloadEmptyMainFuel
Description = XR2 Naquadah Empty Fuel Tank
PropellantResource1 = 0

Save and exit. Voila you can now load an empty fuel tank on your Ravenstar with the payload manager.

 

[dbeachy1]

That behavior is by design. When you spawn a fuel or LOX tank it is always spawned as a full tank. If you want to use an empty tank you can either load the tank in the XR vessel and empty it via fuel dump, or you can save the scenario and then edit it to set PRPLEVEL for the tank(s) to 0 (to empty them).

 

[EndeavourCmdr]

Im more concerned with LOX, which is not a propellant resource, or scram fuel, which again, I believe is handled differently. Believe me Ive already looked at the config file way of doing it. The tanks are either empty and unfillable, or loaded full.

---------- Post added at 11:00 AM ---------- Previous post was at 10:58 AM ----------

That behavior is by design. When you spawn a fuel or LOX tank it is always spawned as a full tank. If you want to use an empty tank you can either load the tank in the XR vessel and empty it via fuel dump, or you can save the scenario and then edit it to set PRPLEVEL for the tank(s) to 0 (to empty them).

So Doug do you have any plans to implement the ability to actually load an empty tank, as an option from the Payload Manager's pulldown list of modules?

Wouldn't it be possible to add another entry to the config file like I described above to gain this functionality inside Orbiter so not have to do it the other way. Having to load a full module and then dump it seems silly, and is definitely not realistic. Having to go outside Orbiter to make an edit creates a discontinuity in the simulation.

 

[dbeachy1]

LOX tanks have a propellant resource like any other Orbiter vessel, it is propellant index #2. e.g.,

XR2PayloadLOX-02-1:XR2PayloadLOX
  STATUS Landed Earth
  POS -80.7057140 28.6322740
  HEADING 150.00
  ATTACHED 0:1,XR2-01
  AFCMODE 7
[COLOR="Red"]  PRPLEVEL 2:0.999985[/COLOR]
  NAVFREQ 0 0
END

To sum up: index 0=Main/RCS fuel, 1=SCRAM fuel, 2=LOX

 

[EndeavourCmdr]

Okay I guess I'm just not explaining this correctly.

Are you telling me that if I wanted to load up an XR5 with all empty tanks, the current way would require me to exit Orbiter, and MANUALLY change the propellant resource levels to 0 for each of the 30 something tanks that I wanted empty??

Doesn't that seem a little bit tedious?

All I am asking is if it would be possible on your end to implement such functionality, since it does appear that others also desire the ability to load empty tanks, and having to do it the current way is a lot more difficult, time consuming, and not as immersive as if we were able to do it using the already built in payload manager, which, although I have not seen the code, I do not know how much time you have to implement such a feature, and I am not familiar with the complexity of the surrounding code, seems to me that it wouldn't be but a few extra lines of code to have the XR parse the payload config files for a seperate optional entry, such as <Fuel at load> which when a value is provided, would be the default amount of propellent that particular payload would have when loaded via the payload manager. This would give the ability to create a payload like "LOX - Empty" or "LOX - Half" which would be refillable to full.

 

[dgatsoulis]

I see what the problem is now. You mean that even though you can load an empty LOX tank, you cannot refill it by using the external supply lines, correct?

 

[EndeavourCmdr]

Yes. I think it would be a really nice feature to be able to select either a full OR empty tank from the payload manager built into the XR, and if I select an empty tank, say, to save on weight, then, when I arrive at one of my stopover points, say, the moon, then I can fill those empty tanks. In this way, I can save on weight during ascent from Earth, since the gravity is much higher and the atmosphere doesnt help much, but on planets with lower gravity and lesser atmosphere, those would be good places to fill the tanks.

 

[garyw]

Are you telling me that if I wanted to load up an XR5 with all empty tanks, the current way would require me to exit Orbiter, and MANUALLY change the propellant resource levels to 0 for each of the 30 something tanks that I wanted empty??

Doesn't that seem a little bit tedious

Whats wrong with spawning the payload then using the scenario editor change the prop level from 100% to 0%?

 

[EndeavourCmdr]

A. Tedious when you have 30 of them
B. Shouldn't be necessary when the XR payload manager already ALMOST does this
C. Scenario editor can't change the propellant level of the grappled cargo bays can it? I tried this easier and the propellant option was greyed out.

 

[Cras]

you best bet here is to load them all into the XR-5s bay, then dump the fuel. Then you can time skip and have the empty tanks in a matter of seconds.

 

[dgatsoulis]

Cras is right. The best way to go about it is to load them and then vent the LOX. Use a little bit of time-warp and it'll be done in seconds.
I understand what you mean when you say

...not as immersive as if we were able to do it using the already built in payload manager...

but this is the way vessels are "spawned" in Orbiter. The XRpayloads are vessels that use simple config files, but even if they had their own .dlls, I don't think that there is a way to create a vessel with a percentage of the amount of fuel/propelantresource it can hold, without having to edit the PRPLEVEL line in the scenario. It's always 100% of the preset parameters.

PropelantResourcei F [F] - TSpecs for propellant resource i (i = or > 1). First value: max. fuel capacity [kg]. Second value: fuel efficiency factor (>0,default: 1)

- (From OrbiterConfig.pdf)

B. Shouldn't be necessary when the XR payload manager already ALMOST does this

I'm not sure what you mean by "ALMOST". If you try to refuel a half LOX tank then you'll get half the LOX a full tank can provide. Half a LOX tank is just a full LOX tank with PropelantResource3 set to 1/2 of what a full one can provide.

Another thing. Since you plan to make a journey that requires to pickup fuel/LOX/SCRAM/ on the way, wouldn't it be better if you didn't have all that deadmass of the empty tanks on your ship, but instead pick them up on your way?

 

[n122vu]

Since you plan to make a journey that requires to pickup fuel/LOX/SCRAM/ on the way, wouldn't it be better if you didn't have all that deadmass of the empty tanks on your ship, but instead pick them up on your way?

This.