Question Forced failures (engines out, etc); has anyone done this?

[Winston Smith]

Hi,

I've been working with the DG4, trying to design procedures for a safe ascent to orbit. By "safe" I mean that the crew should come out alive even if some failure occurs and the ascent must be aborted. They might end up floating in the ocean somewhere, but should be alive.

Toward that end, I've also been forcing failures in the DG4's engines. Right now I'm using OrbConnect, and on a separate Linux box I've got stuff running that waits X seconds, sends the command to the Orbiter PC to set engine thrust to zero, then resends the command once per second (so I can't just turn the engines back on). Crude, but it works.

What I'm wondering is, has anyone developed an addon that causes failures in an Orbiter craft? I'm planning to take this concept further, but if someone else has already done something like this I'll save time and use it (and whatever it is would surely be better than whatever I could come up with). I searched around on Orbit Hangar and didn't find anything but thought I'd ask here. Thanks

Winston

 

[jinglesassy]

AMSO has that

 

[Winston Smith]

AMSO has that

Thanks for the quick response! I'm really hoping there's something more generic, that can be applied to any craft.

WS

 

[andrew]

R-7 Early Missions
[ame="http://www.orbithangar.com/searchid.php?ID=4419"]R-7 Early Missions[/ame]

 

[Sky Captain]

Saving crew from engine failure is easy, just glide to any base within reach or if not possible bring DGIV to lower altitude and speed and eject the crew or do survivable crash landing. A more interesting would be attitude hold autopilot failure during reentry

 

[Winston Smith]

Saving crew from engine failure is easy ...

Really? Give this a try in the DG4

1) Start an ascent to orbit with the PRO-903 autopilot.
2) When velocity reaches 2000 m/s, stop the autopilot. The main engine should shut down automatically, if not, kill it.
3) Without using the main or hover engines, save the crew.

The problem is the ascent profile. Designing an ascent profile which allows the crew to come out alive if the engines fail isn't terribly difficult, but it's slightly more complicated than you make it sound.

A more interesting would be attitude hold autopilot failure during reentry

Agreed. If the ascent is done in a way which allows survival, then the engine failure problem's largely one of reacting quickly once the failure occurs; once the things that need to be done immediately are done, then at that point it's pretty much as you described, just gliding in, etc. That's one reason I had hoped someone had already done a generic "failure MFD" -- I'd also like to throw some other problems into the mix. A stuck RCS thruster that wants to sent the craft into a tumble; gear that suddenly drops and refuses to retract; and whatever else I can think of. OrbConnect is great, but there's only so much that can be done with it.

 

[MeDiCS]

A more interesting would be attitude hold autopilot failure during reentry

That's why I never use an autopilot :thumbup:.

(Even thou' I'm very interested in autopilots, lol)

 

[Sky Captain]

Really? Give this a try in the DG4

1) Start an ascent to orbit with the PRO-903 autopilot.
2) When velocity reaches 2000 m/s, stop the autopilot. The main engine should shut down automatically, if not, kill it.
3) Without using the main or hover engines, save the crew.

That`s easy - just set attitude hold autopilot to 60 deg AOA and you will make it. Temperatures will spike over 2000 degree and crew will G loc but they all will make it allive.

However if autopilot also not work you are screwed since without autopilot it`s not possible to keep recquired attitude.

Since I usually don`t use ascent autopilot and fly DGIV manually like a plane on a low trajectory gradually gaining speed an altitude if had an engine failure at nearly orbital speed I`d just glide and gradually bleed off speed and never reach high G or thermal loads.