Question Functional launch escape system

[vsfx]

Just how difficult would it be to create a generic launch escape tower for use with a manned capsule spacecraft (CTV, CEV etc.)?

I know most launch vehicles don't simulate launch abort situations but I want to make something fairly simple but also useful as my first functional add-on. Multistage is often used to make a just-for-show LES which jettisons in flight but this would not be controllable before being spawned (and I think it would spawn with no fuel anyway due to the multistage bug ?).

I don't no anything about coding, the LES tower would just be a seperate spacecraft3 vessel, so does that leave any other methods? I guess this may be asking to much as it has not be done by someone already. I may just end up creating an LES tower in a ground test type scenario as a practice exercise in making a simple spacecraft.

 

[Zatnikitelman]

Well, if you're using SC3 or Multistage2, you'll be fairly limited in terms of functional. I guess you could have a rocket with a payload of an LES which has a payload of your actual payload, but I'm not sure how functional it would be. The best way really is to custom code it. My Prometheus launcher has LES functionality, and if Microsoft will stop throwing monkey wrenches into things, my upcoming Orbiter Payload Handler framework will ease the use of creating Launch Escape Systems.

 

[Hlynkacg]

Well, if you're using SC3 or Multistage2, you'll be fairly limited in terms of functional. I guess you could have a rocket with a payload of an LES which has a payload of your actual payload, but I'm not sure how functional it would be. The best way really is to custom code it. My Prometheus launcher has LES functionality, and if Microsoft will stop throwing monkey wrenches into things, my upcoming Orbiter Payload Handler framework will ease the use of creating Launch Escape Systems.

So long as the LV uses standard orbiter attachment points or docking ports to secure the payload it wouldn't be that hard to write a generic LES module. However, you're not going to be able to do it with SC3 or Multistage due to the need for certain OAPI commands.

 

[vsfx]

However, you're not going to be able to do it with SC3 or Multistage due to the need for certain OAPI commands.

Ok I guess in the end I'll have to learn how to code but I was hoping this was something simple. I'm finding out that if it hasn't already been done it's not simple!

my upcoming Orbiter Payload Handler framework will ease the use of creating Launch Escape Systems

I like to use Universal Cargo Deck for attaching an upper stage and payloads to different launchers and the OPH add-on sounds similar. Infact you can attach an LES tower as a payload to a capsule using it and it is functional. But to actually use it involves switching vessels and seperating the re-entry capsule from the service module, which in some cases spawns new vessels which then screws up UCD. etc. etc. which is not ideal if your supposed to be blasting away from an exploding launcher a qucikly as possible.

Most launchers I've used don't have abort situations simulated, with the exception of the Dragon launchers by glider ([ame="http://www.orbithangar.com/searchid.php?ID=5442"]http://www.orbithangar.com/searchid.php?ID=5442[/ame] and having them makes launching much more tense a bit like re-entry. Sometimes knowing you are going to get to orbit with no issues makes it less exciting.

 

[Hlynkacg]

Ok I guess in the end I'll have to learn how to code but I was hoping this was something simple. I'm finding out that if it hasn't already been done it's not simple!

I was actually working on the LES for my Apollo addon when I realized that, with a little work, it could be made compatible with almost any .dll based vessel a-la Artlav's Universal RMS.

The main issue is that my method requires access to the simulation's VESSELSTATUS structure and this means a proper plugin module is in order.

I'm not going to post my code because it's still very much a work in progress but the basic theory is this...

• LES is spawned as a independent vessel.
• Object handle for "the capsule" is assigned either via config file or scenario editor.
• Using that object handle the LES module accesses the VESSELSTATUS state of the Capsule and copies the capsule's state to the LES. It also generates a VESSEL Class interface for the capsule allowing the LES module to manipulate the capsule's flight parameters, and state within the simulation.
• Liftoff!
• Abort Initiated!
• Using the class interface the LES cuts the capsule free of the LV and attaches it to the LES as a payload.
• LES autopilot engage!.
• LES THRUST TO MAXIMUM!
• Upon completion of pre-programmed escape profile (or running out of fuel) the LES releases the capsule.
• Capsule plummets towards earth, hopefully the parachutes open but that's hardly the LES's problem, it did it's job just fine.

ETA
It's step 6, cutting the capsule free, that's most likely to cause issues, if the LV isn't using the standard attachment or docking interfaces to attach the payload all sorts of nasty bugs will pop up.