Jump to content

Reentry problems whit my space shuttel


Recommended Posts

HI 

I have a problem with my space shuttle when I going pack to the space center. When I enter a point around 40km to 30 km. I lose ful control of the shuttle and it is spinning and hurling. I have been using this shuttle for a very long time and never had a problem whit reentry. What are wrong and how do I fix it??

Link to comment
Share on other sites

Check where the CoM is in relation to the CoL with the fuel you have at that point. 

If the CoM is at or behind the CoL then you will struggle to get it down. 

Try shifting some fuel to tanks at the front of the craft if possible. 

Link to comment
Share on other sites

Possibly an issue with the CoP (Centre of Pressure) shifting away from CoL during reentry due to high AoA. It would be easier to find out with screenshots of your shuttle (you can't upload images directly on the forums but you can upload them to an image hosting site and simply link them in your post).

Edited by Gaarst
Link to comment
Share on other sites

15 hours ago, Gaarst said:

Possibly an issue with the CoP (Centre of Pressure) shifting away from CoL during reentry due to high AoA. It would be easier to find out with screenshots of your shuttle (you can't upload images directly on the forums but you can upload them to an image hosting site and simply link them in your post).

https://imgur.com/gallery/NMQLU

Here is some pictures 

Link to comment
Share on other sites

@Emilbjorn, I can understand your frustration.  This is a pretty common problem with attempts to build space shuttles in KSP.  Lots of people run into this.

Lots of people want to make a space shuttle, because, well, it's cool.  :)  And KSP makes it really really easy to build a space shuttle, because it gives you exactly the parts that have been specifically designed to look like a space shuttle.

The problem is... it doesn't work.  That is... if you simply put the parts together in a way that looks like the space shuttle, it's horribly aerodynamically unstable and won't fly well.

Here's someone who built essentially the identical ship that you did, and had the identical problem, with a discussion of what the problem is and how to fix it:

A brief Q&A to summarize:

  • Q: Why does my shuttle keep flipping?
  • A:  Because your CoM is in the back, and things with a CoM in the back will almost always flip.
  • Q: But my CoL is behind the CoM, and people told me that's what you're supposed to do!
  • A:  Not relevant here, because CoL is not the important thing.  "CoL behind CoM" is necessary, but not sufficient.  If your CoM is in the back, you're going to flip, regardless of where your CoL is.
  • Q:  But my control surfaces--
  • A:  Also not relevant, because you've put them at the back, right next to the CoM.  And a control surface next to the CoM accomplishes nothing, because it has no lever arm to work with.
  • Q:  Then why does the real space shuttle fly?
  • A:  Because it's not built out of KSP parts and its CoM is much farther forward.
  • Q:  So how can I fix it?
  • A:  See the linked thread above.
Link to comment
Share on other sites

23 hours ago, Emilbjorn said:

 When I enter a point around 40km to 30 km. I lose ful control

On top of what has been said already: maybe its just the plasma blackout messing with you?? It's a setting they introduced not too long ago, and you could toggle it off and try again. Just a thought.

Edited by Dafni
Link to comment
Share on other sites

42 minutes ago, Snark said:

@Emilbjorn, I can understand your frustration.  This is a pretty common problem with attempts to build space shuttles in KSP.  Lots of people run into this.

Lots of people want to make a space shuttle, because, well, it's cool.  :)  And KSP makes it really really easy to build a space shuttle, because it gives you exactly the parts that have been specifically designed to look like a space shuttle.

The problem is... it doesn't work.  That is... if you simply put the parts together in a way that looks like the space shuttle, it's horribly aerodynamically unstable and won't fly well.

Here's someone who built essentially the identical ship that you did, and had the identical problem, with a discussion of what the problem is and how to fix it:

 

Have been using the shuttle for a very long time and it hav been working with out problems and suddenly it could not go through the atmosphere 

Link to comment
Share on other sites

1 hour ago, Emilbjorn said:

Have been using the shuttle for a very long time and it hav been working with out problems and suddenly it could not go through the atmosphere 

Okay, so, if I'm understanding you correctly, this describes your scenario, yes?

  1. It was working fine
  2. You changed something.  Would have to be at least one of the following:
    • What you're doing in-game (ship design, or how you fly it)
    • Something about your game environment (new KSP version, installed a mod, uninstalled a mod)
  3. Now it doesn't work anymore

Correct?  If so, well... what exactly did you do in step #2?

Things don't just "suddenly stop working".  If something was working, and now doesn't, then you just need to identify what changed, and your answer will be right there.

Link to comment
Share on other sites

4 hours ago, Emilbjorn said:

Have been using the shuttle for a very long time and it hav been working with out problems and suddenly it could not go through the atmosphere 

@Emilbjorn are you sure its not the newly introduced Plasma Blackout??

Link to comment
Share on other sites

Your CoL behind CoM,  but the two are very close.  The blue indicator in SPH does not account for body lift, and you have a lot more body ahead than behind.

You either need to allow a bigger margin of safety or install a mod called CorrectCoL that indicates where your real CoL lies.   Also i strongly recommend RCS build aid - gives you a  red ball showing your Empty CoM,  saves you having to keep filling and emptying fuel tanks to check.

I'm not a fan of the Vector engine.  It's too powerful and too heavy, unbalances the orbiter.  It also has crappy vacuum ISP.    The real rs-25 was half the weight relative to the orbiter, only supplied 20% of takeoff power relative to SRBs, but had superb vacuum ISP.

 

Link to comment
Share on other sites

This thread is quite old. Please consider starting a new thread rather than reviving this one.

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...