Chronosheep

Look closer:

My experience so far is the exact opposite: RAPIERs and turbojets have been heavily nerfed (which is a fact. Their ISP is halved, and their thrust heavily reduced). Hardly any of my SSTOs (that were able to get to space with ease in 1.0 and 1.02) are able to get to space anymore, and it takes ages to climb. Seems like i'll need about twice the number of engines I've been using before.

Even if you don't consider this a gameplay problem, is this a reason to be opposed to a more sensible and realistic fuel flow logic? I get the impression that my suggestion would be much better received if I never mentioned rockets flipping at all.

First of all: Yes, it is possible to work around this, but this is not an excuse for having an illogical default fuel flow system in the game. And no, this is not only an issue with poor rocket designs (though this is certainly often the case); it is also largely due to the way fuel is drained. No, this would not at all be unrealistic. You are making the assumption that fuel is contained in a single tank with the length of the entire rocket. In KSP, the fuel is contained in multiple small tanks, and is pumped between tanks. If such a system was used in real life, no sane person would ever start by draining the top tanks. Even if you make the argument that the many small tanks linked together in KSP should be considered to be a single large tank, liquid fuel and oxidizer are in real life contained in separate tanks at different heights in the rocket, and these two tanks would be drained proportionally. In this case, the center of mass stays roughly in place (of course depending on the payload).

Since 1.0.2 many players have complained about their rockets flipping when reaching a certain altitude. The main reason for this is that the center of mass moves to the bottom of the rocket as fuel is drained from the top tanks. A simple fix for this issue would be to change the fuel flow logic to drain fuel from the bottom tanks first, not from the top tanks. The center of mass would then move towards the top as the rocket ascends, and the rocket would remain stable. EDIT: It is obvious that this needs some clarification: In a real life rocket, liquid fuel and oxidizer are located in separate tanks at different heights in the stage. These tanks are drained proportionally, and the center of mass will therefore not move nearly as much is it does when the tanks are drained from top to bottom. In KSP, we have multiple fuel tanks per stage, that drain into each other. If such a system was used in real life, no sane person would start by draining the top tanks. This is not only a problem of poorly designed rockets, as some like to claim (though this certainly plays a role), but is largely a problem with the default fuel flow.

This doesn't seem to be the case. The arrows are still rendered (inside the tanks), but with zero length -- they look like red pancakes.

Thankfully seems to be a rendering bug. Will edit the first post to avoid misleading.

After some further testing, it seems like this bug is circumstantial, and I haven't yet been able to determine exactly what triggers it. I've been using surface attachment, but using the radial attachment point will in some cases also do it. In this case, some tanks are dragless, while others are not: I suppose it's also possible that it's a rendering bug on the arrows. I guess it requires some more testing.

I've been experimenting a bit with the aerodynamics in 1.0.2, and found some interesting, and hopefully useful results. 1. Nosecones: All air intakes, all 1.25m nosecones, and the shielded docking port all produce the same amount of drag. This doesn't seem quite right, since some of the parts should realistically be more aerodynamic than the others. The 1.25m parachutes only produce slightly more drag than the nosecones. 2. Mk2 to 1.25m adapters: Contrary to what you might think, the long adapter produces (slightly) more drag than the short adapter. 3. Back-facing surfaces: A back-facing flat surface produces the same amount of drag as a forward facing flat surface. 4. EDIT: First assumed to be an aero bug, but turned out to be a rendering bug. Sorry about the confusion. Drag arrows do not always render properly when objects are perpendicular to the air stream.

Thanks for the suggestion, but I'm afraid it won't help. Because of the absurdly high lift of the mk2 parts, the center of lift will be too far to the front when there is little fuel left, even if you put all the fuel in the frontmost tank.

The game currently has 3 sizes of (retractable) landing gear: Small, large and gigantic (a.k.a. small, medium and large in the game). It would be really nice to have medium sized landing gear that actually is medium sized. The current medium landing gear is way too large for most medium sized planes.

While Laythe-return SSTO flights appears to be out of range in 1.0.2 (except perhaps for ion or ISRU based SSTOs), getting an SSTO to Duna and back is possible with good margins. This craft has about 5.3 km/s delta V available from LKO, carrying a fair bit of unnecessary oxidizer. I wasted large amounts of fuel during the trip, and still had 1.5k delta V to brake with when returning to Kerbin. Unfortunately, the plane turned out to be completely unmanageable on empty tanks, which resulted in a very Kerbal landing back at Kerbin. Back to the drawing board, I guess..

Let me introduce the future of spaceplane SSTOs: Seriously. I built this as a joke, but it turned out to be one of my most successful designs in 1.0.2. There is absolutely no need for wings anymore. You might think that this thing would drop like a stone when landing, but nope; it floats slowly through the air like a blimp.

I must admit I'm a bit frustrated by this re-balance. Not so much because I don't like it, but mostly because I had finally figured out how to build an SSTO that most likely would be able to return from Laythe in 1.0. Such major changes should come as a patch less than a week after release. In 1.01, returning from Laythe (is at least for me) slightly out of reach. Duna should be possible, though.

Fun challenge. Here is my contribution: going for the unmodded time record.

This sounds like a good opportunity to advertise my interplanetary SSTO spaceplane, the Archangel. (Download available in the Spacecraft Exchange thread) Of the planes posted before, my vote for the best looking would go to Wanderfound's Stratos N.

10 degrees sounds a little low to me. You have to adjust the pitch to keep the vertical speed positive at all times (the vertical speed is the dial next to the altitude counter. The 2 dots between 10 and 100 indicate 20 m/s and 50 m/s). It could also be that you ascended too quickly from 30,000m. You have to make sure to reach a surface (not orbital) speed of at least 2,050 m/s before reaching 34,000m with that version of the plane. Anyway, I have now uploaded a new version of the plane, which is much less prone to asymmetric thrust and asymmetric flameouts. It has a rather different ascent profile than the first version (see new ascent instructions), and is is (in my opinion) much easier to get to orbit. It now has approx. 7,000 m/s delta-v available after reaching LKO.

Thanks, that link was actually quite enlightening. I was not aware that the airflow to the different engines was affected by the order in which the intakes are placed. One of the main reasons why I need so many intakes is that I have to throttle down to avoid asymmetric flameouts. I might try reducing the number of intakes using this trick (though I'm quite happy with the looks of the current design). As for the weight in intakes, it steals about 125 m/s compated to 8 RAM intakes, assuming that the same amount of fuel is used.

The definitions of air hogging and what is cheating is clearly a subjective matter in this game. I personally draw the line at clipping engines/fuel tanks/air intakes into each other in a way that could not conceivably work (unless you roleplay about what the parts actually are). I would, however, much rather admit that this design is cheaty than claim that other designs are not. Realistically, I'd say any amount of intakes that can get you above 30,000m is cheaty to some degree. The reason why I consider intake stacking more cheaty is that you no longer have to take air intakes into account in your design at all - one might as well just multiply the intake area of the intakes by a factor 10. Regarding the number of intakes, I found that this amount is required if you want to do all but the circularization on jet power. It seems to me that the necessary number of air intakes does not only depend on the number of engines, but also on the weight of the craft.

Thanks. The part count is 128. A bit high for a craft this small, but it does have quite many air intakes. Added it to the original post. My definition of air hogging (and what I had the impression was what most people think of as air hogging) is stacking or clipping air intakes in such a way that many of the intakes could not conceivably receive any air. I built the plane in such a way that every intake would realistically be functional, and receive a large fraction of its maximal airflow. Anyway, I removed the [Non-Airhogging] tag from the title to make it less misleading to people who don't agree with my definition.

Hello, Kerbonauts! After following this forum for some weeks, I've decided I'd post one of my own crafts here. Presenting my most successful craft of any kind so far: The Archangel. This is an interplanetary SSTO spaceplane built without any cheaty air intake stacking (where is the challenge in building a SSTO when you have infinite air?), and using only minor amounts of part clipping. I have taken earlier iterations of the plane to Laythe and Duna with plenty of fuel to spare upon return. In the right hands it would probably be capable of an Eeloo return trip. This is a pure pleasure/exploration craft, and doesn't have any cargo capacity (but feel free to build your own cargo version). For Laythe trips, I recommend dumping some of the oxidizer before launching. I also recommend this if you intend to use the jet engines upon returning to Kerbin. The plane is meant to be flown with SAS on at all times. Large amounts of control surfaces keep it fairly stable even when the center of mass and center of lift are far separated (due to fuel consumption). Update 18.01.2015 New version built using the intake placement order trick. This greatly reduces problems with asymmetric thrust and asymmetric flameouts. The plane now needs far fewer air intakes than before, so I have removed a some of them. It still has more air intakes than necessary, but I left them for aesthetic reasons. The ascent instructions have been updated for this version. Features - Roughly 7,000 m/s of delta-v (rocket powered) to play with after reaching LKO. - Belly thrusters for take-off and landing assist. VTOL capable on low-gravity bodies. - Shielded Clamp-O-Tron and docking light. - Probe core allowing for unmanned flights and SAS assist when flown by particularly incompetent kerbals. - Full (somewhat overdimensioned) RCS suite. - All the landing lights you'll ever need. - Part count: 119 Action Groups 1: Switch between Jets to Atomic engine, toggle basic air intakes. 2: Toggle main air intakes. 3: Toggle belly thrusters. 4: Toggle Atomic engine. 5: Toggle Clamp-O-Tron shield and docking light. 6: Extend/Retract ladders. Ascent Instructions - Keep the nose pointed at 60 degrees till you reach 20,000m. Open main air intakes (action group 2) at 15,000m. - Point nose at 30 degrees till you reach 26,000m. - Point nose at 20 degrees until your surface speed reaches 2,050 m/s. Note: At around 30,000m, you will get some asymmetric thrust. Fight it, and do not throttle down. It will go away at around 32,000m. - Once you reach a surface speed of 2,050 m/s, lock the heading to prograde, and throttle down to get a vertical speed of 40 m/s. - Keep adjusting the throttle to maintain a vertical speed of 40 m/s until your liquid fuel level drops down to 1429. If you reach a point where the vertical speed increases even without engine power, leave the engines running at the lowest throttle marker until the liquid fuel level reaches 1429. - Once the liquid fuel level reaches 1429, kill the engines. Switch to nuclear engine (action group 1), close air intakes (action group 2). - Your orbit should now typically be 36-42,000m periapsis, 85-105,000m apoapsis. - Circularize at apoapsis. If everything went according to plan, it should still be above 70,000m when you reach it. Download Fist version was more prone to asymmetric flameouts, and needed more air intakes to compensate. Ascent Instructions - Keep the nose pointed at 60 degrees till you reach 20,000m. Open main air intakes (action group 2) when engines start running low on air (typically around 17,000m). - Point nose at 30 degrees till you reach 26,000m. - Flatten trajectory sufficiently to reach 1,700 m/s surface speed before reaching 30,000m. Throttle down when one of the engines begins to struggle (this also applies to subsequent steps). - Climb slowly, aiming for a surface speed above 2,050 m/s at 34,000m. - Keep 30-40 m/s vertical speed until you reach 40,000m. - When your periapsis is above 30,000m, lock the heading to prograde. Keep throttling down when necessary until the engines are completely shut down. - Your orbit should now typically be 40-45,000m periapsis, 100-130,000m apoapsis. Switch to nuclear engine (action group 1), close air intakes (action group 2). - Circularize at apoapsis. Download