Surefoot

Had the issue where the USModule would block the fuel flow from a tank on its opposite side. Removing then reinstalling the part "solved" it but I was not really confident it would last.. Solution for me was to swap their positions.

Looks like you'll have to either add VTOL capability to your SSTO or find a suitable flat surface (small rocks have no colliders). Another option i've considered is to use that mod which allows building runways on other planets.

Wait til you see a few other places like Eve (the planet) or Laythe

I just landed on Eve on my freshly restarted career. Mind blown, jaw dropped. Well played sir ! This is amazing. I wont spoil the thing (went there without looking at the trailer or anything) so the surprise is intact - it's all worth the trouble.

The tail part seems too small on that SU-34, especially the vertical rudders (but i'd say the rear part is too small in general compared to the front ?). Or is it the camera ? Compared to your SU-27 for example..

Very nice details on that SU-27 !

First make sure your control surfaces, and wing shape/surface are similar to the real thing: Also make sure you try and keep the proportions right (and thus the CoL vs CoM) because that's a key element. Also note how the wing root extensions are done and merging with the fuselage, and how they cover the intakes (which are not too far behind the cockpit actually). I know first hand it's a lot of hours of work doing all that fine detail, but Sukhoi are into fine details that are kinda important to aerodynamics... Once you have a really close model, you'll find out it's completely unstable and will flip over immediately. You need the AtmosphereAutopilot mod that simulates the fly by wire system of modern jets. Just set the limits in AA to decent realistic values, and you'll have an SU 27 that flies almost like the real thing (edit) from what i see in DCS (and i suppose it's like the real one) the edge slats are working in counter-AoA mode.

Impressive models here, i can see a lot of attention to details, what mod did you use to get the fuselage so perfect ?

You still need to work that model a bit here's a mig 35 isometric projection view: It should be wider and shorter in length. Also notice how the air intakes are completely hidden below the wing root extensions (and not sticking out).

That F-14 is looking good ! Did you manage to recreate the variable wings or are they just swept all the way permanently ?

It does mostly, and if you stick to (proven) realistic designs they usually work very well. That's the main reason why i love FAR so much and spent hundreds of hours tinkering with aerodynamic designs. It's like "build-your-own-X-Plane" simulator Fighter jets usually fly pretty much like in the best flight sims out there, which is amazing.

I use both B9PW and Procedural Parts, they work fine in 1.3.1.

Procedural wings is a must have, keeps part count a lot more reasonable.

They seem to work, at least the flight model of my KU-57 seems realistic enough, although i have limited elements of comparison (SU-33 simulation in DCS or other flight sims). I know the SU-33 (it's basically an SU-27 with canards) is not the same design as SU-57 but it takes from the same bag of tricks and is also naturally unstable. On my flight tests with FAR i notice the leading edge AoA slats will definitely improve handling at high AoA and delay stall. With thrust vectoring i can even throw the plane around at such high G's i'll just disintegrate the airframe from the stress. Putting a G limiter on AA makes it fly mostly like an agile SU-27. The real world SU-27 has also very wide flight characteristics and is able to pull damaging G's if you override the joystick limiter, to pull aerobatic figures like the "cobra". Yeah that turns out to be similar to how they work on real models, you can watch them in DCS for example on SU-27 you'll see the leading edge slats countering AoA. Same goes for the F-15 "side pods" extensions, they do move counter to AoA (although in a very limited manner). And yeah on that F-22 photo you can see them clearly too. (edit) on that very nice SU-57 photo they are also quite obvious:

Yes, if possible you should have elevators near the center, and flaperons as far as possible on each side (see how the B-2 achieves it). It's not the guarantee of a perfectly stable aircraft though, if your CoL shifts too much when opening the bay (and that pressure curve doesnt look good...) that might be another cause for instability. I'd try to add more yaw authority first, in any case.

Others will comment better than i do, but i give a few hints: I see an aera ruling issue here, coupled with a distinct lack of vertical surfaces. You should first try and reduce the area behind the bay, or give extra width to the area around the bay (or move it backwards, that would reduce the impact). See that yellow line, it should be as straight as possible. Then you seem to lack control surfaces, are you using flaperons for yaw control ? If not, try either adding control surfaces used as assymetric airbrakes for yaw control (there's a specific option given by FAR to allow this) or increase substantially your vertical tail fins, current ones are way too small, and way too tilted so they'll produce pitch/roll coupled with the yaw and have a very weak yaw lever. (edit) also where is your CoM in relation with your CoL, what's happening probably is open bay doors add a hint of lift and move the CoL forward which would bring more instability.

Yeah he got the body / fuselage quite right, impressive. Getting the wings and elevators perfectly matched is a lot easier.

The problem with canards and forward swept wings, is the bad re-entry heat/mechanical resistance. Canards will take a lot of heat being out of the shock cone, and fw swept wings will take a huge load out of the slightest AoA bump. I'd rather stick to standard tailless delta, even though these tend to have lawn dart behaviour...

I used the diagrams i posted above, which i believe represent the real F-15. Thing is the MK2 body is a bit wider, otherwise i tried to respect proportions, also you might be induced into thinking that because of the stubbier nose (nothing i can do there, i have to do with the MK2 parts i have). Like i said, it's quickly slapped together, not up to the level of detail of my KU-57. It still flies rather well and has fighter-like agility.

If you want to do a F-15 that works you have to pay attention to all the aerodynamic details (wing surface ratio, thickness, anhedral, sweep, etc.), all proper control surfaces sized like the real one, and the CoM should be really near the CoL almost on top of it. Fighter jets are very twitchy by nature. Just look at the KU-57 example i posted on previous page (page 47) here, it flies very well but i had to go into a lot of details to be close to the original. If i look at that blueprint: I can see that the wings have a specific shape, slight anhedral, are top mounted, and pitch ailerons are quite offset to the rear possibly for increasing their authority. The wing root starts with a weird oblong shape that's on the side of each intake, i suppose that's for area ruling (which is also a thing in FAR so we have to pay attention to it), i also notice the "thin waist" and on photos of the real thing the rounded shapes for each engine pod. Notice each control surface size and shape, and the big fixed twin vertical tails. Taper is also taken into account by FAR somehow and it's noticeable on that blueprint. The F-15 has no leading edge slat (notice the difference between control surfaces and leading edge of each wing) so it should be a relatively straightforward design to do in KSP. Intake pods cannot be done exactly like on the F-15 but we can do something close. (edit) slapped something together very quickly: Yep, it works It's not as unstable or twitchy as my KU-57 but flies still very nice. Of course there's no double cockpit length wise in KSP so the front is a bit shorter here. I think i got the system to make that F-15 apart from the intakes i'm not happy with what i did there. I also could elongate the cockpit by adding a fuselage section behind it. But that was a quick job and the CoM is really well where it is now. So yeah, it flies, it rolls pretty well and has enough pitch authority to destroy itself from G forces and incoming airflow. Also it's a stable design, so SAS is enough to fly it.

Land it vertically, on its tail ?

@Jonney5 it works like a charm, thanks a lot

The patch works for Realchute parachutes, but stock ones are still missing ?

If you want that one (now called KU-57 ) i can send you the .craft file Flies very well, definitely needs Atmosphere Autopilot as it's an unstable design, and of course it's made with FAR in mind. Love your mod Simple, clean, effective, makes flying planes and spaceplanes a lot more pleasing.

The Rafale is also built for high AoA, so far in combat exercices it's superior to most alternatives, be it BVR or dogfight. The Russians may be thinking in similar ways, that once the BVR exchange of formalities is done, it's high G time, and there whoever can manoeuver the best has a much easier time. If you play a bit on DCS World you can see the strengths of SU-27 vs F-15 for example, it's quite interesting.