Peter Balholm

The specs for this engine are all messed up. It was designed to work with Realism Overhaul, and it does work well in previous versions. However, RO uses different units for thrust, fuel volume, etc., and so without RO, it doesn't make sense. That is why its TWR was so low it couldn't lift off at all. I have just arbitrarily decreased the fuel load to make it lift off, but I have not attempted to get it exact an realistic. BTW, this is a hybrid rocket based roughly on this design: In my alternative storyline, it is used for a Mars mission in 1917. I have a story plotted with hundreds of characters, only two of whom are fictional.

Here is my folder from inside GameData. Perhaps the parts would all work, but the "FirstStageEngine" is the one I am working with right now. https://drive.google.com/file/d/0ByFshSPbart8cTlUZ0s0aHJUTWs/view?usp=sharing

After a lot of deleting and reinstalling mods in various combinations, I have found that the fundamental problem is caused by Realism Overhaul. Without it, the engines work great, even in the modded version. I don't strictly need RO, but would like to figure out how to make my engines compatible. I haven't found anything on the forums right off. Any suggestions? Thank you so much for all your help!

I reduced the fuel load and now it works, in the basically unmodded versions. It does not work yet in the heavily modded RO/RSS 1.2.2. In this, it has no thrust (exactly zero) and does not even register as an engine on the staging diagram. This was my original problem, of course, and it was what led me to not suspect that the problem in the unmodded versions was different, since it acted much the same. Only Kerbal Engineer could show the difference. So, do you have any thoughts on what could be disabling my engines in the modded version? I have tried removing RealFuels, but that did no help. I will be gradually reinstalling mods and seeing what makes a difference.

Thanks to your advice, it got off the ground! Hooray! More specifics later.

I have tried modifying my .cfg from the mainsail engine. I have removed the fairing module, etc. The only part I have added is propellant. This is a hybrid rocket, and so contains its own propellant, like an SRB does, but is throttleable. Like my other version, it still produces no thrust. However, it does not display the flame effect or sound until it is staged. Here is the .cfg file: https://drive.google.com/file/d/0ByFshSPbart8Y29WeHg1NWhGT1E/view?usp=sharing

https://drive.google.com/file/d/0ByFshSPbart8TVF2cGxncXUxVGs/view?usp=sharing I believe this should do it. Sorry about the delay. This is learning curve with more than just KSP!

Okay, first, if I paste a picture into the comment box, it displays nicely, but then disappears when I actually post. Back to the Imgur technique, I guess. Here is a link to the .mu file for my engine. https://drive.google.com/open?id=0ByFshSPbart8TVF2cGxncXUxVGs

Here is a picture of the second-stage engine. I can't find the file for the first stage right now. They act the same, I believe. By the "model" you mean this Unity file, right? How do I upload it? Can you point me toward instructions?

I removed the animation module. Thanks. It still doesn't work. The other symptom I have noticed is that as soon as the vessel is loaded on the launchpad, the exhaust and engine noise are going. before I have throttled up or staged. And then, when I do stage, there is the clunk noise of the engine starting, but no thrust. Does that help?

Okay, I just stripped my install of KSP 1.1.3 down to nothing but Squad parts and my custom engines. This makes it a direct comparison with my 1.2.2 install. Now, the two exhibit the same behavior! Neither works. Here is a picture, after my rocket tipped over. Perhaps it had a tiny bit of thrust; I can't tell. But it certainly didn't have enough even to scoot it sideways. So, my engines do not work in either unmodded install. They work in modded 1.1.3, but not modded 1.2.2. (My mods, by the way, run heavily toward RO and RSS.) I'm puzzled. Any thoughts?

I have a thrust transform on my model. Is it a child of the "Game Object" in the picture you posted? (The hierarchy still confuses me.) If it helps to narrow down the possibilities, my engine works in 1.1.3. So I feel that it should have everything there. There must just be some slight glitch. Thanks!

I have built my own engines for KSP by the usual methods; Blender, Unity, and then modifying a .cfg file to fit my specific engine. The engines work just great in KSP 1.1.3. However, when I install them in KSP 1.2.2, they have no thrust. They use fuel, produce smoke, and make noise; they just do not have any thrust on the pad and no thrust is computed on the stats in the VAB. I am using a completely stock install of 1.2.2, except for the engines, which are in their folder under GameData. Here are two photos of the same part in action in both versions. Here is my .cfg file: PART { name = hybridFirstStage module = Part author = Peter Balholm, after Kartoffelkuchen mesh = model.mu rescaleFactor = 0.7 node_stack_top = 0.0, 33.42, 0.0, 0.0, 1.0, 0.0, 1 node_stack_bottom = 0.0, -4.4, 0.0, 0.0, -1.0, 0.0, 1 TechRequired = start entryCost = 0 cost = 2000 category = Engine subcategory = 0 title = Hybrid First Stage Engine manufacturer = Sarawak Tank Company description = A hybrid rocket engine which can be clustered to build the first stage of the Cassandra rocket. The oxidizer tank is bamboo plywood and holds nitrous oxide pressurized with gaseous oxygen. The fuel is paraffin wax and powdered aluminum. The sea-level nozzle made of Baekelite reinforced with asbestos fiber. // attachment rules: stack, srfAttach, allowStack, allowSrfAttach, allowCollision attachRules = 1,1,1,1,0 // --- standard part parameters --- mass = 3.33 dragModelType = default maximum_drag = 0.2 minimum_drag = 0.2 angularDrag = 2 crashTolerance = 7 breakingForce = 200 breakingTorque = 200 maxTemp = 3600 RESOURCE { name = LiquidFuel amount = 6012 maxAmount = 6012 } RESOURCE { name = Oxidizer amount = 24048 maxAmount = 24048 } EFFECTS { running_closed { AUDIO { channel = Ship clip = sound_rocket_hard volume = 0.0 0.0 volume = 1.0 1.0 pitch = 0.0 0.2 pitch = 1.0 1.0 loop = true } PREFAB_PARTICLE { prefabName = fx_smokeTrail_veryLarge transformName = smokePoint emission = 0.0 0.0 emission = 0.05 0.0 emission = 0.075 0.25 emission = 1.0 1.25 speed = 0.0 0.25 speed = 1.0 1.0 localOffset = 0, 0, 1 } MODEL_MULTI_PARTICLE { modelName = Squad/FX/ksX_Exhaust transformName = thrustTransform emission = 0.0 0.0 emission = 0.05 0.0 emission = 0.075 0.25 emission = 1.0 1.25 speed = 0.0 0.5 speed = 1.0 1.2 } } engage { AUDIO { channel = Ship clip = sound_vent_soft volume = 1.0 pitch = 2.0 loop = false } } flameout { PREFAB_PARTICLE { prefabName = fx_exhaustSparks_flameout_2 transformName = smokePoint oneShot = true } AUDIO { channel = Ship clip = sound_explosion_low volume = 1.0 pitch = 2.0 loop = false } } } MODULE { name = ModuleEnginesFX thrustVectorTransformName = thrustTransform engineID = AJ-26-62 runningEffectName = running_closed exhaustDamage = True ignitionThreshold = 0.1 minThrust = 0 maxThrust = 924 useEngineResponseTime = False engineAccelerationSpeed = 20 heatProduction = 400 fxOffset = 0, 0, 1.5 PROPELLANT { name = LiquidFuel ratio = 0.4 DrawGauge = True } PROPELLANT { name = Oxidizer ratio = 1.6 } atmosphereCurve { key = 0 345 key = 1 268 } } MODULE { name = ModuleGimbal gimbalTransformName = AJ-62_Engine_Nozzle gimbalRange = 4 } MODULE { name = ModuleAnimateHeat ThermalAnim = --None-- } MODULE { name = ModuleAlternator RESOURCE { name = ElectricCharge rate = 8.0 } } RESOURCE { name = ElectricCharge amount = 0 maxAmount = 0 isTweakable = false hideFlow = true } }

I'll try to increase the torque by rearranging my engines. I'll also try MechJeb. I didn't know that I could still use it. I suppose I just keep the Stability button clicked on TCA, and nothing else?

I added four BIG thrusters (c. 75 kN) and put them right up near the top. It flies straight up beautifully, and doesn't deviate more than a degree or two. (of course, other than the RCS, I have no roll control). But when I set the orbital autopilot, It still does the wobble at 1500 meters, and goes completely off the rails at 6000 meters, shutting down entirely. Thank you for the formula, by the way. It makes it all much less mysterious! So, it would appear that the gravity turn is kicking in too fast for even my enhanced craft, and forcing it to shut down. I tried to fly it nearly straight up, basically beyond the atmosphere, and then hit the Prograde control. I had hoped that this would force it to thrust over at the horizon. But It did not seem to try, and continued at about a 60 degree angle. I don't know what I should do, but let me explain how this rocket's throttle steering should work, in my fictional real-life. The cluster of 127 rockets would all fire at launch. The rocket would lift off. If it got a little off course, all of the rockets on one half of the rocket (roughly 60) would throttle back. In an extreme situation, they would shut down entirely for a moment, perhaps. Thrust would be lost, of course. But under no circumstances could it drop below 50%. To make this work with the first stage (for example), I would probably rebuild my part files. Instead of having one giant cluster with 18 strapped-on control rockets, I would have one central rocket (required by symmetry) and six-pie shaped wedges of clustered rockets. (It is sixfold-symmetry because that is how cylinders pack the best--the reason for honeycomb.) Each of these wedges would be one engine as far as the game was concerned. Therefore they could be throttled up and down and control the ship with a great deal of authority, and the part count would only be 7 for the entire first stage! My question is, can TCA control such a craft? Could I get past the shutdown gremlin? Thank you for your help!