what settings to use for Deadly Reentry and Far?

[jarmenia]

I've been following along with Scott Manley's interstellar quest. Looking at the mod list here: http://www.reddit.com/r/KerbalSpaceProgram/comments/1upc6g/scott_manleys_interstellar_quest_modlist/ It says that he reduced Deadly Reentry's settings to compensate for FAR.

I have been unsuccessful in finding what settings I should be using. I tried reducing heatMultiplier to 22 but am still burning up in a sub orbital flight. I read in the DRE config that I may want to change the schockwave settings, is that true?

Thanks.

Edited June 4, 2014 by jarmenia

[TechnicalK3rbal]

The default settings work fine for me. I still don't understand why he changed them.

[Taki117]

I also dont have any issues with stock settings. If you are burning up on a suborbital flight make sure the command pod (or whever is on the bottom of your craft) has a heat shield.

[jarmenia]

Here are some screen shots to show what's happening. My decent doesn't seem to steep, and I do have a heat shield as you can see.

[ArcFurnace]

What was your periapsis before you began aerobraking? If you lower your orbit until it intercepts the ground, it may not look steep, but it's actually steep enough to seriously stress your heat shield, if not overload it to the point of failure. I find an initial periapsis of between 25 and 30 km will guarantee single-pass capture without overloading your heat shield (using default DRE settings). That way you do most of your braking in the thinner upper atmosphere. In that picture you posted, you're moving at 1800 m/s at less than 8 km altitude; that's definitely way too fast to be that low.

Note that this means that suborbital flights can actually be more dangerous than returning from orbit, since by definition your periapsis won't be very high.

Edited June 4, 2014 by ArcFurnace

[jarmenia]

This was suborbital, I never got me Periapsis above the ground. Apoapsis was about 90 km.

[xandalis]

The problem you're having (parts attached radially to the command pod) isn't settings, it's placement. It's very very hard to tuck larger parts like the goo canisters "inside" the area heat shielded area on that pod. Try a girder under the pod, science stuff on the girder, and a 1.25m heat shield under it all. Also, shoot for a 20-25km periapsis for reentry, when in low orbit. Higher orbits will lead to you needing to do at least some level of speed braking before you hit atmo. If your speed 3km/s or higher when you hit lower atmo, you'll have problems anywhere from excessive G's, to burning up (or both). Quicksave/load or sandbox for practice without killing your career kerbals.

[jarmenia]

The problem you're having (parts attached radially to the command pod) isn't settings, it's placement. It's very very hard to tuck larger parts like the goo canisters "inside" the area heat shielded area on that pod. Try a girder under the pod, science stuff on the girder, and a 1.25m heat shield under it all.

Ok, I'll give this a shot but the goo blowing off is only half the problem. The entire heat shield gets used up and the capsul burns up at the end.

Also, shoot for a 20-25km periapsis for reentry, when in low orbit. Higher orbits will lead to you needing to do at least some level of speed braking before you hit atmo. If your speed 3km/s or higher when you hit lower atmo, you'll have problems anywhere from excessive G's, to burning up (or both). Quicksave/load or sandbox for practice without killing your career kerbals.

The periapsis never got above ground. The apoapsis was about 90km so there was really no way to make the slope much flatter.

[Taki117]

It looks like you have 2 heat shields(The MK1 pod has one built in), this shouldn't be necessary, even for a sub-orbital flight. You are also moving way too fast at 8km than what you should be. Also, if your Apoapsis is 90km you shouldn't be moving that fast that low which means something is wrong somewhere. Now then, what I suggest is that the next time your ship explodes take a look at the flight log (F3) to see what exploded and why. You may not actually be overheating but instead being destroyed due to over-G.

[jarmenia]

I also dont have any issues with stock settings. If you are burning up on a suborbital flight make sure the command pod (or whever is on the bottom of your craft) has a heat shield.

I will also add, if I turn FAR off, I have no problem returning without burning up.

[Jananton]

I too was 'captured' by Scott Manley's Interstellar Quest and I can vouch that certainly in the beginning stages of career mode the game is strangely more difficult then later on when one is able to get to orbit. Suborbital flight seems the most prone to going south since you're landing angle is mostly too steep for comfort, lost two Kerbals in the process that way, something that never happened to me before.

As others said before I just use the default settings for Far and Deadly Reentry. The only thing to really watch out for is keeping the periapsis between 30 and 32 km height to have a shallow long stretched entry through the upper atmosphere to lose enough speed. As for parts sticking out outside the heat shield like goo containers for instance, I didn't have any problems with those as long as I observed the reentry heights given above and making sure my velocity stayed under approx 2850 m/s when hitting the thicker air layers at 30 to 32 km height.

Greets,

Jan

[Taki117]

I will also add, if I turn FAR off, I have no problem returning without burning up.

Sounds like it might be a FAR issue (Though I don't see why) you might want to make sure that FAR is properly installed and updated (same with DRE)

[Specialist290]

I will also add, if I turn FAR off, I have no problem returning without burning up.

This leads me to conclude that the point of failure (I'm reluctant to call it a "fault," as it's a natural consequence of the way FAR is designed to change the way aerodynamics works) is a result of FAR's behavior. In the way stock aerodynamics works, drag is applied for every part on the craft regardless of whether it's in the airflow, while in FAR the cross-sectional area of the craft as it faces into the wind actually matters. The net effect is that more actual drag is applied in stock aerodynamics, which causes the craft to slow to terminal velocity much more quickly than in FAR -- which means less time for the craft to absorb shock heating from the extreme deceleration, and thus less heat absorbed by the craft overall. At least, such is my theory, assuming I'm properly understanding how FAR and DRE work together.

I've got an install of KSP that has both DRE and FAR, and I can confirm that it's entirely possible to recover a craft from either a suborbital or an orbital flight safely with the stock settings. If you're going to be doing any more tinkering with the plugin code in the DRE configs, I've found this handy post where he explains what each of the parameters does and how they work together; it might help you make everything fit together.

Hope this helps!

[ferram4]

The problem is that you've clipped the unnecessary 1.25m heat shield into the Mk1 pod (which already has a built in heat shield) in a way that prevents FAR from applying drag properly. You've glitched the vehicle, and that's why it's having problems. Get rid of the heat shield and it will fly perfectly fine.

[Hodo]

Your decent is to steep. Your PE is to low, set it to 25KM like others have said.

FAR should not have an affect on re-entry heat.

[jarmenia]

The problem is that you've clipped the unnecessary 1.25m heat shield into the Mk1 pod (which already has a built in heat shield) in a way that prevents FAR from applying drag properly. You've glitched the vehicle, and that's why it's having problems. Get rid of the heat shield and it will fly perfectly fine.

This was the problem. I removed the heat shield and the goo containers as well as the capsule made it down in one piece. Even with a steeper decent it worked fine. Thanks for the help, that was really frustrating.