camlost

Simply making thrust scale with Isp will not solve problem #1 mentioned in OP. Also I don't think that adding a third curve would suffice. Some kind of hard cap would be needed to nerf the thrust at low altitude, AJE users would know what I mean. And then, the key thing is that IntakeAir as a resource must be get rid of.

What you described is basically AJE: the over heating ,ramjet, etc. SSTO is still easy on Kerbin, and something like Skylon is possible on Earth.

That's interesting, did he get any response?

First, Problem 1 can be solved be adding a CoMOffset to the part. Problems with the main topic: 1.The current system is built around "IntakeAir" as a resource. You did not make clear of whether it is to be remained. If so, limiting and categorizing inlets will not stop people from spamming it but encourage it further. And as long as they are spammed, the thrust will be the same at altitude. Auto-throttle-down when IntakeAir is insufficient was implemented in v0.21 but it does not solve the problem. Besides, the number seems arbitrary and lacks realistic reason, and it could be rather confusing to players. 2.Speed performance and fuel efficiency are intertwined not separated. For example, high bypass turbofans have high Isp, low TWR and works at low speed only. Afterburning turbojets have low Isp, high TWR and works at high speed. It is hard to imagine an engine that has high Isp, low TWR but works at high speed. That is against thermodynamics. The reason why rocket engine have choices like that is, they choose different cycles (closed cycle vs. gas generator etc.). Jet engines are not that case. 3.The nozzles are not like rockets where you worry about expansions. Jet engine nozzles are variable at the throat, in order to cater to different throttle and speed. Having them perform differently solely based on altitude is incorrect (that it rocket thinking into jet realm again XD) 4.The whole system contains too many configurations (3x3x3=27) that are categorized arbitrarily, thus difficult to balance.

Just in this specific case, how can we justify the mysterious "IntakeAir"? And who's dev really? I think the whole system was made by C7 as a mod.

I'm pretty sure that speed can be reached if the parameters are set right. I make sure of that in AJE even. Players need to change the playstyle a bit: a small price to pay. But the inevitable aero overhaul is the same, why not do everything right?

Question is, did you have great fun because of it or in spite of it?

Yes. That's why IntakeAir needs to be got rid of. IMO? I only stated facts. I have zero interest in your opinion or how you or anybody play. I, as a customer, have problem with how KSP is designed. Yes, you can even use jet engines as first stage. Won't happen with a correct thrust/altitude relationship. In reality, people refer to TWR at sea level when they talk about airplanes. It's probably fine to have a TWR=15 turbojet, but thrust really needs to change with altitude properly. It is not a good approximation of anything, because of the two problems I stated.

The thrust doesn't decrease with altitude, you cannot find such curve in cfg. In 0.22 version or something, Squad added a function to auto-throttle-down the engines when IntakeAir is not enough. That is wrong and totally missed the point. Engines need inlet to work, but simply adding more inlets will not make engine work better at high altitude. They claimed to have done it to improve game experience. However this is the exact problem that encourages intake spamming. My point again: IntakeAir must die. Using IntakeAir as a resource is unreal, counter-fun, and encourages stupid things.

I agree with that. However in defense of the stock aerodynamics, it is not the aerodynamics itself that encourages bad habits, it's the control being jumpy, the runway being short, the engines being overpowered, the inlets being nonsense and such things that encourages bad habits. In short, the whole thing is a mess. And for those of us who come from other flight simulators, we come with good habits formed in those softwares. Of course we want FAR so everything would make sense. A week into the game I converted to FAR and never looked back. An example of good habit/bad habit: pulling 15G's at sea level and supersonic speed is crazy, and should never work.

In my mod, CoM offset was implemented to deal with this problem about 4 months prior to OP. It's always a good thing to do research on all available mods regarding the topic before suggesting.

Really? I highly doubt that, and I never seen any dev mentioning what I said. Ignoring such serious issues for more than two years and not touching it is not a compromise.

Tested with the same craft as above, indeed the bug's fixed. Don't know how to thank you now. XD

No, that would be even worse. What really should be is that the Isp stays roughly the same, but thrust decreases in high altitude, so less fuel is burnt. That's why passenger planes always cruise at 30000 feet. Divide the Isp by 15 has a huge impact on plane designs, and everything especially fuselage has to be re-balanced. Maybe because jet engines are difficult and rarely taught. We've seen home-made rockets but there's no home-made turbojets. However, that is no excuse to ignore the issues. The two points I've made are as bad as the aerodynamics, has been there for as long as the aerodynamics, yet nobody realizes how serious it is. All these proposals about re-balancing stuff completely missed the point, instead they need a complete overhaul, as badly as the aerodynamics.

Now that Squad is finally reviewing their aerodynamics, I feel it's about time to stress the problem with jet engines. Flying airplanes in stock KSP is truly weird, but 'souposphere' is only half the concern. The erroneous jet engine/inlet model ruins the game no less, yet not talked about as much as the aerodynamics. Initially, all engines in KSP were rockets, they have a max thrust and a curve of altitude vs Isp, a simple model that works fine. And later on, jet engines are added as derivation of rockets, on top of the Isp curve, a speed vs thrust curve is added. Jet engines also requires another resource named IntakeAir, that is created by inlets. This model is totally wrong and leads to terrible mistakes in two aspects. First, thrust is dependent not only on speed, but also on altitude (roughly proportional to static air pressure). Also, Isp should be dependent on speed besides altitude. Second, when we talk about Isp (usually 2000-4000s range for jet engines) we are referring to the consumption of fuel, not including the air going through the engine. However, in KSP the IntakeAir is also counted as a fuel. Take the 'basic jet' part for example, the actual Isp is 15x higher than what the game says. Players are heavily misled by these problems. Because thrust doesn't decrease with altitude, basically any design can reach high speed and altitude with enough wings and controls. As long as there's enough IntakeAir, the engines can push the aircraft all the same, and when IntakeAir runs out, they suddenly flame out. The unusually high Isp makes a player never care about the fuel. The result is clear: it encourages engine spamming and inlet spamming, that's why you see them so much. It also makes hypersonic flight a trivial task, which it really shouldn't be. Why nobody cares then? Maybe I need a PR campaign? I think the reason lies in how things are balanced: people would just make a plane and say 'hey it flies' or 'hey it SSTOs' and be done with it. Hopefully applying mistakes on top of other mistakes (aka souposhpere) makes things right? I don't think so. Bugs are bugs not features and they should be fixed. Now that they are finally redoing the aerodynamics, maybe it's time to review the jet engines as well. It's a shame that these problems goes unnoticed forever.

On inlets, pls read the OP.

Tested with the same craft as above, still having the same stalling effects.

I don't think anybody in this thread reported 'improved' stalling. This doesn't make any sense as stalling has nothing to do with speed. What he said is merely that he made a delta-wing glider, which doesn't use flaps anyway. The aerodynamics would be wrong nonetheless, if FAR wasn't able to solve the wing interaction.

Area is proportional to thrust, but you'll need more inlet area as well. For more stuff about the parameters and physics look for my other repo on github. Nonetheless, I don't see why you'll want to buff the thrust of SABRE.

How's that different from what I said? OK a little different, but that is on another level of simulation, we need to reach that level first, by making the compressor more real with performance maps

with 0.13 adn FAR dev version, both the ailerons and the flaps are 15 degrees.

Currently there isn't an intercooler. I just pretend that SABRE is a turbojet with super-high temperature tolerant compressor. The reason is I don't think it makes too much difference, a cooler merely transfers energy from before the compressor to after the compressor.

1.Since you're already using RSS, the increase in SSTO difficulties is trivial, since you'll spend most of the fuel in rocket mode anyway. Someone posted a working skylon pages back. What really is affected is aircraft designs 2. It's not always a nerf. At certain points it is more powerful than without AJE. It's not my intention to nerf or buff anything, I just want realism and realism is all I want. I never care about disabling or enabling certain kinds of designs. 3. I appreciate the endorsement from RO guys, but RO still works without AJE, just missing some realism. @Tellion, As said, the LH2 has much higher combustion heat than kerosene. But it also has very low density, so you'll need big tanks. What's really bad is when you don't have RF. Also keep in mind that Isp is heavily dependent on throttle, speed, temperature. Also, SABRE is an imaginary engine with little data, that is to some extent different from a turbojet. So don't expect too much realism, I can only say it makes more sense than the stock.

Already calls that? what is the name of the function?

That should not be part of this mod. What you reported should because of AJE setting max temp but not the heatproduction of the second engine module. I'll try fix this in dll