miyuruasuka

The bug was in RealismOverhaul. It attempts to overwrite all the engines. It will be fixed, apparently, in the next version of RO. Sorry for bothering!

Apparently not. The mentioned file seems to attempt to put ModuleEnginesRF on everything to hack RealPlume on all engines. It broke KSPI horribly. After removing it, KSPI works perfectly and there doesn't seem to be anything else that has broken.

As I said, there's no specific config file that mentions the engine. StoryMusgrave's suggested hack (in the RO thread) of removing "RealismOverhaul/RealPlume_Configs/000_Generic_Plumes_Catchall/000_ModuleEnginesFixer.cfg" works perfectly for me. (By the way, why do I have to keep repeating that this is not due to RO having a broken config that changes the engine? This is a problem with RO attempting to convert everything to Real Fuels even for engines that already support RF fuel names using the stock fuel system, and has *nothing* to do with there being a config changing the engine.)

Thanks, I'll try and see whether it works. By the way, what's the rationale for RO touching engines that it doesn't have configs for?

So over at the Real Fuels and KSPI Extended threads, I've been trying to hunt down what's causing KSPI Extended engines to not scale thrust when propellants change, a bug that happens only when Real Fuels + Realism Overhaul is installed. Considering that KSPI Extended engines are labeled "non RO", I was not expecting RO to touch the engines at all, but somehow it breaks the engines. StoryMusgrave claims that RealismOverhaul "touch[es] ALL engines by changing them from ModuleEngines/FX to ModuleEnginesRF", and that this probably broke the engines. Is this true? If so, is there some way to force RealismOverhaul to *completely* ignore certain engines?

I'm not claiming it's a Real Fuels issue. As the other user said, it's probably because RealismOverhaul is "steamrollering" over everything. I was just asking whether there was a workaround (say, by config file) or not; I have no intention to blame RF. RO is weird in that it touches *every* engine whether there's a config for it for not, and somehow this touching breaks KSPI but not most other "non RO" mods. I'll post about this in the RO thread.

So if I understand correctly, there is no way of working around this issue unless ModuleEngineRF fixes its steamrolling over non-RO engines?

The "4.0 kN" thrust value is essentially pulled out of some @$$. It also doesn't scale with different fuels. It's also wrong in asserting that the engine consumes LiquidFuel only: it consumes all sorts of fuels, and they all work properly, with the correct Isp even, but the thrust is always stuck at the totally wrong 4 kN value. Removing RealismOverhaul/RealFuels makes the bug disappear. Clearly something is forcing the engine to ignore KSPI when calculating its own thrust; however, scouring the whole GameData directory I couldn't find any ModuleManager patch patching over this engine specifically. KSPI also does set the thrust correctly *somewhere*: MechJeb thinks the thrust is the value given in the KSPI documentation, and thus is also massively confused.

I'm the user who reported the problem. I'm fairly sure that the engine pack (Realism Overhaul) did not touch the affected engines. In fact, the affected engines have "(non RO)" displayed over them. Perhaps it's the attaching of the "non RO" label that messed things up? The engines are also not "altered" in the sense that any specs, ModuleManager-wise, seems to have changed. Instead, there's a new field "Real Fuels" in the VAB part description, and the thrust is stuck at the value in that field rather than varying procedurally (based on the fuel given, reactors, etc).

Can you explain exactly in what way is RealFuels taking control over engines? I think this is simply because KSPI doesn't use SolverEngines, and I think that you should consider moving to it, because AJE and a few other mods also use SolverEngines.

It happens with all the engines. It's always stuck to the thrust listed in the VAB. Please fix this ASAP, it makes Interstellar really unplayable for me because I rely heavily on RealFuels. I'm ending up only using the reactors for electricity. Edit: I'm guessing this has something to do with RealFuels' usage of SolverEngines (similar to AJE); could you look into better integration with SolverEngines with KSP Interstellar, maybe even use SolverEngines to implement thrust switching etc?

No, the issues is not with MechJeb. There is no issue as long as Real Fuels is not installed. Please see these screenshots: https://imgur.com/a/HqPe0. The thrust should be 12.4 kN in space, and it is without RealFuels, but with RealFuels it's stuck at 4 kN. *This* is what confuses MechJeb, because it's getting conflicting values from different places.

When RealFuels is installed, KSP Interstellar's engines have the wrong thrust values. Essentially, no matter the choice of reactor, etc, the thrust is always fixed at a particular, arbitrary value. The easiest way to reproduce this would be to get the CANDLE and turn it on. It always produces 4 kN in vacuum, no matter what type of fuel you give it, although the Isp does properly change. This is more than a nuisance even though the wrong value is generally in the right order of magnitude, because MechJeb and other similar tools actually think that the maximum thrust is the correct value, when in reality it's stuck at, say, 4 kN for the CANDLE. This means that MechJeb starts burns at the wrong time, crashes probes attempting to use the landing autopilot, etc.

Random thing: shouldn't the first page and the title be updated? I was really confused for a while and thought AJE had been suddenly abandoned, since I see "April" and "[0.90]"...

That is something I will definitely do once I get back home. It would be on 0.90 with the last stable version of AJE, though. - - - Updated - - - It's a constant, though. In real life, for a converging nozzle, it should start near 1, and approach 0 as the speed increases. Currently, there is no speed (according to AJESolverTester) at which a turbofan would start to produce "negative" thrust. The NetThrust decreases as ram drag increases, but after a certain point, the increasing thrust overpowers it, and goes into speedy ramjet mode. I'll demonstrate this once I get on my KSP computer.

A simple test with AJESolverTester would make it very clear: no matter what parameters you put in, as you increase speed thrust increases without bound. This is also a problem with NASA EngineSim, though. I wonder whether there is some approximation being made by the thrust-calculating code that has diverging error as speed increases. Also, it's not just "my vehicle", but a large number of vehicles I've built. Even vehicles that do work to real-life spec (for example, a MiG-21 clone I built) experience this problem if I give it a push with a rocket over Mach 2.0: the SNECMA turbojet would suddenly start going faster and faster, and you just can't get it to stop: cutting throttle doesn't work since the engine spools down slower than the thrust increases. By "gigantic turbofan" I mean the CFM whatever. It does dramatically reduce thrust as you get up to around 500 km/h, but starts picking up thrust afterwards. If you disable overheating, you can get it to produce as much thrust as you like by simply boosting it to supersonic speeds: it will then self-sustain, producing more and more thrust until the plane falls apart due to aerodynamic forces. Essentially, my subsonic airliners would fall apart due to Mach effects if I don't reduce throttle as I speed up. I remember that in real life, airliner's maximum level-flight speed is limited by thrust + drag, not overheating or airframe integrity.

Nobody commenting on my issue with the jet engines' spiraling-out-of-control thrust? Surely I'm not the only one finding this annoying?

I've noticed that in AJE, almost all jet engines would pick up thrust if you make it go fast enough. Throttling during cruise is like managing a ramjet: a bit too high, and there's a vicious cycle of increasing thrust and increasing speed that destroys the plane (or maxThrust is hit). A bit too low, and you end up settling down into a much slower cruise speed. This is especially serious for high-speed engines like the YJ93. You easily enter into an uncontrollable thrust mania at high Mach, where even at 5% throttle the thrust levels continue to climb. Several times I had to cut fuel flow completely to save my plane from self-destruction. And no, I'm not putting too much engine on too little plane --- the static TWR is about 0.2. Is this realistic? I think that for most engines that aren't designed for high-speed operation, making them go fast would actually reduce thrust. It's well-known, for example, that for high-bypass turbofans the static thrust is the maximum thrust. The SR-71's J58 seems to be the only engine for which the increasing thrust behavior is realistic. It's a bit ridiculous to have airliners with high-bypass turbofans overspeeding and tearing themselves apart when under full throttle. The YJ93 should cruise at Mach 3 only under continuous afterburner, so that seems grossly unrealistic too? Even with a maxThrust, this seems highly unrealistic: most engines gradually reduce thrust after the design speed, rather than simply starting to increase thrust more slowly. And finally, even if all this behavior is in some sense realistic, I doubt that fuel turbopumps can simply operate at arbitrarily high fuel flow rates? (I've noted that this behavior seemed to become much worse after the "engine code redo" on GitHub; my gigantic turbofans used to decrease thrust gradually until there was an equilibrium with the drag, now they decrease thrust a bit until ~0.5 mach, then just turn into huge ramjets again)

Is there any threat that RedAV8R could delete all the repos?

Sorry if I seem impatient, but when would 8.0 be coming out? I would be extremely happy to use RF on KSP 0.25...KSP without RF is not like KSP anymore to me

Sorry if it's a stupid question, but do you have FAR installed? The stock aerodynamics has *MUCH* more drag than in real life.