Lt_Duckweed

Today, I flew on Duna using stock jet engines

The reason being that restock very slightly changes the colliders and the drag cubes and thus is technically not stock physics. So this mod is for people like me (I run and film stock missions). I want good looking plumes, but need to stick with the stock parts & models.

For the purposes of landing, do water landings count or must it be on land?

Nerv does help though. On my Eve sstos, I use a ratio of 2 nervs for every 1 vector. I start up the nervs and vectors at the same time at 16.5km, the vectors then run out of fuel at a surface speed of about 2500m/s and the rest of the trip to orbit is done by the nervs. With these ratios I have been able to achieve 5% payload fraction to orbit. Ideal twr in terms of efficiency balance between engine dry mass and total fuel load seems to be ~78 tons per 1 vector and 2 nerv. So for a 176 ton ssto this translates out to 2 vectors, 4 nervs, and ~8.8 tons of payload. I found in my testing that taking away a pair of nervs and replacing with more fuel for the vectors had a negative impact on payload.

For an Eve ssto, ions don't make sense unless you are trying to get back to Kerbin. The total impulse you can extract from an ion engine on an ssto ascent is less than the impulse you can get by just replacing the ion engine with liquid fuel for your nervs.

Even at the top of the highest mountain on Eve Nervs produce 0 thrust, so no way to spin the props. Unless you mean using the nerv ec to power the prop, which might work, depending on if ec scales with throttle or real thrust.

A large drill has a base rate on asteroids of 5 ore a sec, which means it can power 10 recipes. A small drill has a base rate of 1 ore per sec, so it can power 2 recipes. To get more fine grained: The base rate for the liquid fuel + ox mix is 0.5 ore a sec for .55 ox and .45 liquid fuel. The base rate for ox only is .55 ore a sec for 1.1 ox. The base rate for liquid fuel only is .45 ore a second for 0.9 liquid fuel. The base rate for monopropellant is 0.5 ore a sec for 1 monopropellant.

I know this answer is really late, but there is another option. Currently they bend and flex because the thrust from the rapiers is not pointing through the attachment point of the servo. If you use the shift key to increase offset range, you can offset the engines so that they are centered on the attachment point of the servo. This should let you get away with a smaller, lighter servo while also having much less flex.

You can aerocapture everywhere (including Eve) without using any ablator, as heatshields are already insanely heat resistant on their own.

Looks like none of the forum css is able to load for some reason.

It does not. The wings will behave entirely normally.

Considering the number of blades you are using, you can almost certainly drop one size down on the rotors and use the medium rotors. This will let you use 16 rtgs instead of.... 100

Essentially, there are a number of different parts in the game that can under the right circumstances produce lift to drag ratios MUCH higher than what is possible with standard wings. The very simplest is the small retractable landing gear. Simply roll it 90 degrees so it is sideways, then angle the front upwards about 30 degrees. This particular one can give a lift to drag ratio about 3x higher than what can be done stock (stock max supersonic/hypersonic lift drag is in the range from 4.3 to 5, depending on mach number, with the landing gear trick it is nearly 15. They range anywhere from the 15 lift drag of landing gear, all the way up into the multiple 100's depending on the part.

More specifically, nuclear engines are one of the parts that cause it to stutter, don't know if there are others but thats the biggest offender for me. To add to this, there will be 3 numbers in each row. First number is currently exposed area of that face of the drag cube (taking node occlusion into account), second number is how streamlined this face of the drag cube is (0 is infinitely pointy, 1.00 is a flat plate, anything bellow .45 is good, bellow .3 is really good), the third number is the total area of that face of the drag cube. So you can compare the 1st and 3rd values to see how much of that face is currently covered.

Yes, it is modeled. In fact, at subsonic speeds, backface drag is nearly as bad as frontal drag.

As long as you build a well optimized craft, just barely dipping bellow 120km and then going back to orbit isn't all that difficult. Speed of sound is very high on Jool so heating isn't nearly as bad as you would expect, and 120km on Jool is the equivalent of about 8km on Kerbin so even Nervs will work reasonably well (and you should use nervs for the high delta v). Basically you want minimal wing area so you can preserve as much speed as possible, use fairings as nosecones, and try to get town to 120km while still at 2000m/s or so, then ignite the nervs and burn back to orbit. As a note, I say "not too difficult" but that presupposes already having a good grasp on aerodynamic flight. I would recommend watching this tutorial: I would say that once you understand the importance of wing incidence (explained in the video) and can get liquid fuel only sstos into kerbin orbit with several km/s left over you will be ready to tackle a Jool diver.

It sounds like the effect of the rapier cone is strongly tied to the rapiers/ton ratio of the craft. I was only getting a 2% decrease, but I was also taking off from the runway at nearly 44 tons on a single rapier.

That's where ksp gets tricky. L-I-D is the drag that comes as a result of the fact that in ksp the lift from wings is parallel to the wing surface, not the velocity vector. This vector gets decomposed into actual lift, and lift induced drag. The actual drag listed in the action windows for wings, or displayed via the F11 arrows, is considered to be parasitic drag. The true lift induced drag will be both of these drag values added together. The true fuselage parasitic drag will be quite low. On the setup I've been toying around with: Cruise altitude: 22300m at start of cruise. Cruise speed:1658m/s at start of cruise. Mass: 37,934 kg DeltaV: 47,367m/s Total drag: 33.32 kn Lift to drag ratio: 4.191 Fuselage parasitic drag: 2.80 kn (0.75kn from rapier engine, 2.05 from everything else) Game "lift induced drag": 12.02 kn Game "wing parasitic drag": 18.5 kn True lift induced drag: 30.52kn Thus the breakdown of drag on my craft is: Fuselage parasitic drag: 8.4% (Rapier: 2.25%, rest of the body: 6.15%) Lift induced drag: 91.6% Thus it can be seen that it is VASTLY more important to optimize lift induced drag by mounting your wings at an optimal angle of incidence. This also plays into my opinion that the rule against rapier rear cones is dumb, sure it's ~25% of total body drag that you would save, but in the grand scheme of things it's only about 2% of your total drag, and thus one of the least important things to optimize. You save more by learning to build a well optimized craft in general.

What AoA are you using? Hypersonic lift/drag ratio of wings begins to fall off after 5 degrees AoA so if you are using, say, 10, that would degrade your l/d ratio, while also having you flying at a higher altitude, meaning more drag and less thrust for a lower top speed overall.

Quick question, would having some wings in a bay be against the rules? Basically, be able to open the bay for some extra lift during takeoff, but be able to close them away during cruise to have a lower cruising altitude (depending on the exact craft dynamics a lower cruising altitude can be counter intuitively more efficient). They wouldn't be physically clipped, just located within the bay.

That's exactly what this is about lol. On a lot of my more optimized sstos/planes in general (intended as exercises in theory more so than any practical craft) I am pushing takeoff mass per rapier well north of 40 tons, some even as high as 50+. I ramp up the hills to the west, then accelerate down the hills and across the flats before climbing onto the runway from the side at a very shallow angle, then take off at the end of the runway much like any "normal" plane would. This allows for very high fuel fractions and thus very high dv.

Removing the node via module manager will do nothing to reduce the drag. Drag in ksp is calculated off of "drag cubes" which have surface area and "pointiness" factors for each of 6 different faces. Each node on a part is assigned to one of the 6 faces. Drag cubes can only ever be modified by node attatchment, NOT by deleting a node in the part deffinition. When you node attach two parts, the drag cube faces tied to each node are compared. The ways this can turn out are: 1. The smaller face (by surface area) is removed entirely. The larger face has the surface area of the smaller face subtracted from it, and it's pointiness factor adjusted to reflect the shape of the surface area still exposed. 2. If the two faces are exactly the same size, both get removed. 3. If they are close in size, but don't quite match, its a bit inconsistent but sometimes the pointiness of the larger face gets set to 0, making it infinitely pointy, and thus effectively removed.

Question, one of the rules mentions that you must take off from the runway. But it mentions nothing about the takeoff run needing to be entirely on the runway or not. So my question is: as long as I spawn on the runway, and my wheels leave the ground for powered flight on the runway, does the location of my craft between these two events matter?

For cargo bay occlusion, ksp does not care about where you attached the part, only that it is physically inside the bay. You can attach parts anywhere on a craft and offset them into a bay and the bay will shield them.

I'm fairly certain this s a visual UI only bug. Stratz and I saw something very similar with our Jool craft, where the blades still had drag listed in their part windows, even though the bay was closed. But it was purely visual, the blades were actually producing no drag, but when you closed the bay it didn't update the UI correctly.