Kurld

Hi, ferram4. KJR is pretty much the first mod I ever add to a new install. Recently I noticed some weirdness when I use my PEBKAC LES mod with KJR: The jettison engine part is stretching/separating away from the escape engine/tower/cover part like there is a rubber band between. As soon as the jettison engine runs out of fuel, the parts snap back together. The only mods are mine and KJR and the phenomenon goes away when I remove KJR from the mix. Craft file: KSP Log: Spacedock link to my mod Thanks! Please let me know if you see anything in my mod that would be causing this.

Oddly enough, it is Kerbal Joint Reinforcement. That was the first mod I loaded into the stock install beyond my own. After adding it the problem is replicated and after I remove it again it goes away. I really don't remember this happening before yesterday, though.

And, oh joy, it does not do it in a stock install. So now to isolate which other mod is causing it to do weirdness...

I reloaded the original part that I had made and it is doing the same thing.

I'm really stumped as to what's going on here. I've never seen this before, except sometimes with docking ports. And even that stuff has gone away with KJR. This part is just a solid rocket booster, stacked on top of the main LES rocket/tower/bpc. Anybody got any idea what's going on? All I did was create a new model for the part. Original never did this. EDIT: maybe I just never noticed it.. but now it does do it. Also, after the jettison engine burns out, the parts jump back together.

I've been working a bit on a LES for the BDB mod, as well as going back and cleaning up some of my models and textures here and there. Things are kind of slow, but I hope to have something out in the next month or so. In the process of making the BDB LES, I experimented with how to go from three parts for the Apollo-style LES to a single part. I was never able to get the flight characteristics to behave the way I wanted. I think I need to go back and re-examine where the center of mass really "should" be in the unified assembly. Sometimes I really wish I had paid more attention in math class.

LOL, but better than never. Thanks!

I made some progress on a LES that will fit the BDB CM:

I'll look into it sometime.

@CobaltWolf I didn't really play with it much yet, but the Apollo CM is very nice work, so much so that it's likely to take over the top spot for 3-kerbal pods in my builds. I was all set to go down the path of modeling an Apollo CM of my own, but now I can push that plan off indefinitely. Best of all, the Apolllo-style LES I made for my PEBKAC Launch Escape Systems mod will be fairly easy to adapt to fit perfectly on this CM. Apollo BPC

Sweet! If this is as good as it looks you probably saved me from a good many months of OCD modelling!

Thanks! The nosecone has an aerodynamic lifting surface that only generates actual lift when then canards on the nosecone are deployed. These canards only deploy about 11 seconds after the abort key is pressed. So, if the flipping you are talking about happens during an abort, when the canards deploy, that is intended behavior. The Apollo LES did the same thing in real life so that the CM would be pointed the right way for the parachutes to deploy safely. If the flipping you are talking about is during a normal ascent, I don't think the nosecone would be causing that. I'd like to take a look at your ship and see what's going on and make sure I'm not causing the problem, though.

After more testing: in certain configurations and circumstances there is a collision when the SDHI/PEBKAC hybrid LES jettisons, which destroys the SDHI docking port parachute part. During one test, KSP crashed. So, the "weld" approach is not going to work reliably. Not sure what I can do at this point that wouldn't require more time than I have available. The debug log is filled with "Ignore collision failed. Both colliders need to be activated when calling IgnoreCollision" even before the craft is launched. I'm guessing this is probably because there are two colliders.. one for the original part and the other for the SDHI blast cover.

I downloaded SDHI and played with it some. I was able to weld it's blast cover to the version of the PEBKAC escape tower/motor that has no BPC. I had to recompile the PEBKAC parts model in Unity because it was using the same thrustTransform name for its escape motor as the SDHI parts jettison motors. It seems to work OK. I'll try to upload a new version later this week after I test it some more and finish balancing the new part with the existing SDHI parts.

@davidy12: I looked at the SDHI page. It uses the stock Mk1-2 pod, so what I've provided for stock should work if you use my parts instead of the ones from SDHI. It might also be possible to create a part config that will let my plugin code work with @sumghai's models. I may have time to download SDHI later today or tomorrow and see what I can come up with.

Have you tried using it with SDHI? I think somebody up-thread remarked that it worked well with that mod. That was over a year ago, though. I'll add it to my list to check it out, in case it's something super-easy. Otherwise, I may not get to it for a few months... I need to carve out some time to actually play this game for a bit and catch up on what others have been doing!

I've updated the mod. It now includes two new escape-tower/motor parts. One is for stock but has no BPC. Somebody requested this long ago for Ven's stock revamp. I've never used that mod, so YMMV. The other part is for Frizzank/DennyTx's FASA Apollo CM. I stopped short of finishing all the nitanoid details of the aft BPC, but I got so sick of looking at it... The source code for the plugin is now at https://github.com/Jurld/PebkacLaunchEscape Thanks to linuxgurugamer for adding this to CKAN! Enjoy the parts, and drop me a line with any requests! Barring anyone making any, I am going to let this rest for a while...

I've been working on the models for the no-BPC and FASA versions of the 2m pod escape parts. The lower BPC for the FASA Apollo pod is taking some time to get right, but it's getting there.

Yep, as others have pointed out, the problem is the design of your rocket. The center of pressure is almost certainly above the center of mass and that is a surefire way to guarantee you will not go to space. Try playing in sandbox mode for a bit and construct a rocket that looks like the following: http://imgur.com/UhQKGYS That engine is the LT45 "swivel" which is a gimbaling engine that will help you maneuver. The similar looking LT30 does not gimbal and is not what you want. Note how the center of lift (blue orb) is far below the center of mass (yellow orb). This is what you want in your own designs. Anyway, try flying this rocket for a while until you get used to the controls. Don't try to turn much until your speed is > 100m/s. Throttle back as you climb and burn off fuel and try to keep your acceleration < 3g's or so. With a little practice, soon everything about flying will become second nature. Good luck!

Thank you!

Thank you! I've set up the account at AVC and created a version file. It will be included in the next release. I'm thinking I'll probably move the source code out to Github.

You asked about controls, but I'll start by pointing out that, with a properly designed rocket, you will barely need to touch them. Without seeing your design, it's hard to tell if there is a real problem there or not. Maybe you can post some screen shots of your rocket? The main reason rockets become unstable is because the center of mass is "behind" or "lower" than the center of pressure. The game really doesn't give you a way to see where the center of pressure is located (it is dynamic based on many factors), but center of lift is close enough. As long as your thrust vector is not "off-center", it doesn't really matter where it is located in the vertical axis. You mentioned using wings... if you have less than 3 and they are not 100% symmetrical, it will cause stability problems. Try using the Basic Fin before moving on to something else. Several things can happen during flight that can turn an otherwise "stable" craft into one that becomes impossible to control: You burn off fuel as you ascend, which shifts your center of mass "down". If it gets low enough, it can fall below the center of pressure and your craft can become very unstable very quickly. I mentioned that center of pressure is dynamic, based on a lot of things. The only time it really corresponds to the center of lift shown by the game is when the rocket is pointed within about 5 degrees of prograde and moving at less than mach 1. Any more than that and it can move around quite a bit, depending on your rocket design. To avoid problem number one, right click on your fuel tank(s) and empty them in the VAB. Check center of mass and center of lift to be sure that the CoM is still at least a rocket diameter or two "above" the center of lift. To avoid problem two (aside from ensuring your fins are completely symmetrical), make only very slight, very brief control inputs. Keep the reticle in your navball no more that 5 or 10 degrees of prograde. The prograde marker itself is about 5 degrees in diameter. At launch, turn on SAS and do not touch ANYTHING until you get moving at least 150m/s. As you get more confident at flying, you can start turning sooner, but you need a good bit of speed before your fins will help much. Keep your acceleration under control. If you start seeing aero or heat effects in the lower atmosphere you need to back off the throttle or else be VERY careful to keep things pointed as close to prograde as possible. All this being said if your design is correct and if you don't ham-fist the controls, when you stop giving input, the craft should return to prograde all by itself. SAS can make things "interesting" sometimes, especially if you have fins or wings with controls surfaces or engines that vector thrust. Try running without it after you get off the ground and gain some speed. As far as the controls themselves: If you tap "W" it will try to point the craft towards the "top" of the navball. "S" is the opposite. "A" will try to point you at the left and "D" will try to point you to the right. "Q" will roll the craft counter-clockwise and "E" is clockwise. Good luck!

I'd like to learn how to do it, but that would be great for the short term. Can you explain how I might better organize the zip file?

I will add an INSTALL.txt file in the next update. As for CKAN, supposedly it was added there by Spacedock... but I'm not seeing it in CKAN either. Not sure what I need to do now.

I've updated this mod: jettison of the LES is now optionally stage-able from right-click menu added an agency for PEBKAC Heavy Industries that will give you flight-test contracts in career mode reduced cost of the Mk1 LES compared to the system for the larger capsule