My Findings for my current launch problems

[The D Train]

So, with help from two kind people from the community "Vanamonde and DeMatt" (Thanks to you both) I solved the problem of securing the SRB's to the side the Orbiter with the use of struts as instructed. However, it turns out there was a much bigger problem causing the in flight break up. The first thing I noticed was that the anomalous events would take place at a definitive moment during the vehicle climb out. Somewhere around 15k. The anomalies being, a strange snap/click/buckling sound coming from the vehicle, after which the entire vehicle would pitch steeply and the break up would occur. I noticed that when this strange snap or clicking sound would take place, there was a marked deceleration and the engines seemed to get quieter. I started to wonder if for some reason the main Orbiter engines were the issue. Perhaps the engines were running out of fuel. However, while watching the fuel gauges on left by the stage display, the main engines still showed fuel to be burned. I checked the fuel window that shows all the fuels on board and their status's and saw again that there was still fuel left to burn. Then I noticed the Oxidizer. 0/2750. I ran the launch again and watched the Oxidizer drain to 0 and all of the anomalous events once again took place. There was fuel enough left to burn alright but, it couldn't burn anymore. No Oxidizer. Which I learned after looking up rocket engines and SRB's and learning what I could about fuel/propellant mixtures and how Oxidizer is required. I thought Oxidizer was only needed in space where there's no atmosphere or oxygen to be had. Apparently it's needed on the ground as well.

After all of these findings I concluded that, the Oxidizer was running out, the main Orbiter engines could no longer produce thrust, symmetry was gone, the SRB's thrust took over, overwhelming the SAS stability control and the sudden pitch of the vehicle caused the in-flight break up.

Next task? Figure out the solution to the loss of Oxidizer. If there is any other solution other than merely carrying more Oxidizer.

If anyone after reading this sees that my logic or understanding of how these things work is flawed, please let me know what I'm missing. I'm eager to learn more if I can. My hope is that this might help someone else avoid this mistake during their KSP travels. Thanks!

Edited June 13, 2015 by The D Train

[SAI Peregrinus]

There are several kinds of engine in (stock) KSP:

Solid boosters, Liquid fueled engines, Jet engines, and RCS thrusters.

Solid boosters come with their (solid) fuel and engine attached. Things like the RT-10 are solid boosters.

Liquid fueled engines use Liquid Fuel and Oxidizer, and require both. These are things like the LV-T30 and LV-909. They can NOT take intake air in place of Oxidizer. For an IRL equivalent, they'd be burning something like unsymmetrical dimethylhydrazine as the liquid fuel and dinitrogen tetroxide as the oxidizer.

Jet engines take Liquid Fuel and Intake Air. They also require both to operate. They can NOT take Oxidizer in place of intake air.

RCS thrusters take monopropellant only, and are used for precision maneuvering.

Right-clicking a part in the parts list will show what fuels it takes in the detail pane.

There are also some niche engines, with more specific purposes.

RAPIER engines are a sort of hybrid that can act like jet engines or like liquid-fueled engines, depending on their mode. They're good for space planes.

NERVAs are nuclear-thermal engines, they use only use Liquid Fuel (no oxidizer) and are only good in space (not for early stages of lifters). They're highly efficient but weak, good for interplanetary transfers.

Ion engines use electricity and Xenon. They're very weak, and don't work in atmospheres to any appreciable level. They're mostly for very light probes.

Edited June 13, 2015 by SAI Peregrinus

[The D Train]

There are several kinds of engine in (stock) KSP:

Solid boosters, Liquid fueled engines, Jet engines, and RCS thrusters.

Solid boosters come with their (solid) fuel and engine attached. Things like the RT-10 are solid boosters.

Liquid fueled engines use Liquid Fuel and Oxidizer, and require both. These are things like the LV-T30 and LV-909. They can NOT take intake air in place of Oxidizer. For an IRL equivalent, they'd be burning something like unsymmetrical dimethylhydrazine as the liquid fuel and dinitrogen tetroxide as the oxidizer.

Jet engines take Liquid Fuel and Intake Air. They also require both to operate. They can NOT take Oxidizer in place of intake air.

RCS thrusters take monopropellant only, and are used for precision maneuvering.

Right-clicking a part in the parts list will show what fuels it takes in the detail pane.

There are also some niche engines, with more specific purposes.

RAPIER engines are a sort of hybrid that can act like jet engines or like liquid-fueled engines, depending on their mode. They're good for space planes.

NERVAs are nuclear-thermal engines, they use only use Liquid Fuel (no oxidizer) and are only good in space (not for early stages of lifters). They're highly efficient but weak, good for interplanetary transfers.

Ion engines use electricity and Xenon. They're very weak, and don't work in atmospheres to any appreciable level. They're mostly for very light probes.

Thank you very much for the overview of various engines. I noticed you said "stock". I'm guessing there have been many addon engines and rockets developed since KSP launched. Any addon recommendations? I also noticed that the most popular addon from I can tell is this "MechJeb". A tool to help streamline and perfect vehicle functions I assume? Worth getting?

[Harry Rhodan]

I also noticed that the most popular addon from I can tell is this "MechJeb". A tool to help streamline and perfect vehicle functions I assume? Worth getting?

MJ is a full suite of autopilot and information overlays. If you just want the readouts you should look for Kerbal Engineer Redux (KER) or Vessel Orbital Information Display (VOID).

If you are looking for something specific there's a nice thread in the addon forums: http://forum.kerbalspaceprogram.com/threads/55401-Community-Mods-and-Plugins-Library (I would recommend parts from Nertea and/or Necrobones as they look extremely "stockish")

[jwenting]

I'd start figuring out the stock engines and fuels before installing addons that add even more variety

MJ is a great tool, Lots of functionality. Some people consider its option to help control vehicles as "cheating" or "destroying the game". If you feel like that, just don't use those functions (they're not mandatory to use...).

For me, after launching hundreds of things by hand, I'm more interested in designing and planning missions and let the autopilot handle the throttle levers for me

[Snark]

+1 to SAI's excellent overview of engine types; basically, if you're running a conventional liquid-fueled rocket engine, give it tanks that have a full load of both fuel and oxidizer.

I'm curious about your description of how you hit a problem with things going asymmetric when you run out of oxidizer; it's hard for me to picture your ship design. Are your SRBs and/or liquid-fueled engines not symmetrically arranged? I can imagine how running out of oxidizer could cause you to not have enough total thrust, but I'm having trouble seeing how it would make things asymmetric.

[The D Train]

MJ is a full suite of autopilot and information overlays. If you just want the readouts you should look for Kerbal Engineer Redux (KER) or Vessel Orbital Information Display (VOID).

If you are looking for something specific there's a nice thread in the addon forums: http://forum.kerbalspaceprogram.com/threads/55401-Community-Mods-and-Plugins-Library (I would recommend parts from Nertea and/or Necrobones as they look extremely "stockish")

I will look into Nertea and Necrobones. Thanks for the tip and information on Mechjeb!

I'd start figuring out the stock engines and fuels before installing addons that add even more variety

MJ is a great tool, Lots of functionality. Some people consider its option to help control vehicles as "cheating" or "destroying the game". If you feel like that, just don't use those functions (they're not mandatory to use...).

For me, after launching hundreds of things by hand, I'm more interested in designing and planning missions and let the autopilot handle the throttle levers for me

I can understand the desire to preserve the challenge by not using tools that create full automation. After all, many people that use simulations like this, want to simulate the entire experience of having to do things manually or "by hand" and work their way up to easier days. Just like we did with NASA. That's why I love simulations. Especially ones that strive for realism and immersion. It gives you a unique perspective on what it was or is like when you can't actually be there yourself. I've launched and failed so many times that, I imagine what it must have been like in NASA's early days. The Astronauts routinely risking their lives for the Adventure of the Century. The "New Frontier" of spaceflight. My experiences also taught me how complicated the process really is. Why attention to detail is needed. The need for the creation of checklists, contingency procedures etc... One thing that has stuck out in my mind is how at least in KSP we can slap on SAS and test some things out without having a Kerbal on board, risking his little digital life. Astronauts like John Glenn, Ed White and Alan Shepard weren't that lucky. And in Ed White's case, unfortunately we didn't have automation to test things out even during ground testing. All that being said, I will still try out Mechjeb at some point. After I learn to do things the hard way and manually I hate the fact that I don't have a joystick to use. Makes things even tougher for me. Thanks for the information you provided!

+1 to SAI's excellent overview of engine types; basically, if you're running a conventional liquid-fueled rocket engine, give it tanks that have a full load of both fuel and oxidizer.

I'm curious about your description of how you hit a problem with things going asymmetric when you run out of oxidizer; it's hard for me to picture your ship design. Are your SRBs and/or liquid-fueled engines not symmetrically arranged? I can imagine how running out of oxidizer could cause you to not have enough total thrust, but I'm having trouble seeing how it would make things asymmetric.

Snark, I'm sorry for the confusion. I probably just used the term incorrectly. What I meant was, when I lost the Orbiter's main engine due to the lack of oxidizer, I lost thrust on that side of the vehicle when before that happened, I had the thrust from the two SRB's plus the Orbiter engine. So, it was a bit more equal. Once the Orbiter's engines seized up, the whole vehicle pitched over. I'm assuming from the sudden loss of thrust from one side. If there is a word used to describe the placement of engines in order to create an equal amount of thrust, then that is what I mean. Again, sorry for the confusion

[moogoob]

I find Mechjeb worth it for the customizable engineering readouts alone. Of course, Kerbal Engineer does the same thing, too.

As far as autopilot is concerned, while I do a fair amount manually still (docking, most landings, all rover driving) I go all the way when using probes - I try to design it so that NO manual input is allowed, only commands through Mechjeb's various autopilot modules. It's a probe, after all. It HAS to land by itself! It becomes an engineering constraint - How can I design this so that even Mechjeb won't mess things up?

EDIT: Well, next to no manual input. When doing probe missions I do allow hitting the "stage" button, right-click actions and action groups. They're sometimes needed, but i try to minimize it.

Edited June 14, 2015 by moogoob

[MarvinKitFox]

When doing probe missions ....It HAS to land by itself

If you want realistic probe landings, then install RemoteTech. With communication delay.

You land a probe on Duna, and tell it to throttle up. 25 minutes later, the throttle goes up!

[Michael R]

I can understand the desire to preserve the challenge by not using tools that create full automation. After all, many people that use simulations like this, want to simulate the entire experience of having to do things manually or "by hand" and work their way up to easier days. Just like we did with NASA.

I'm fairly sure that no NASA astronaut manually piloted his rocket off the launch pad, nor routinely had to bet his life on his ability to manually start and stop a maneuver burn with precision timing (absent an Apollo 13 type incident). These are arcade game skills, and while I highly recommend everyone learn to do everything in KSP manually first, to me, adding the automation to some of these steps adds realism, and doesn't take me out of the experience the way that key mashing does. If my rockets fail, it should be because I designed them or used then incorrectly, not because my finger slipped.

But I appreciate that other value different experiences in KSP. For an extreme example of play that's totally opposite of my style, watch

. That's why this is such an incredible game. There are so many different things to do, and so many different ways to play. It's a single player game. There's no such thing as cheating. Do what's fun.