MaxL_1023

The drag force is proportional to the cross-sectional area, drag coefficient and the vehicle velocity. It is independent of vehicle mass (and therefore likely liftoff thrust). A 1.25m rocket would experience 1/4 the drag force of a 2.5m rocket using an identical boby shape and ascent profile. However, your rocket is 8 times heavier (mass scales with the cube of radius). Therefore, the drag force would only cost half as much delta-v due to your higher mass and inertia. Basically, 2.5m or 3.75m rockets are far better at overcoming drag due to their sheer mass - it becomes negligible for 3.75m stacks especially with decent payload shapes/fairings. I routinely launch groups of 4 2.5m or 3.75m stacks held together with struts and a central payload (only way I can find to get 200 tons to orbit) and drag is not an issue with a 1.25 starting TWR - the engine's control authority from thrust vectoring is larger than any drag force assuming my AoA is not crazy.

Eve still shouldn't burn anything up above 80km assuming a 90km cutoff line. It has 5 times Kerbins sea level pressure, so unless the scale height is much larger (which seems unlikely due to the strong gravity) the pressure on Eve should "lead" Kerbins by about 10km. Basically, something moving at 5km/s which would burn at about 60km on Kerbin would feel the same drag at 70km on Eve. It looks like you guys model a very steep pressure rise at the very top of the atmosphere - is there any way to flatten it out a bit so that there is a zone of aerobraking regions which would only take a few m/s with negligible heating?

I survived a ballistic eve landing with no chutes or engines by using 8 over-sized landing struts - they all exploded on impact and the main body landed soft as a breeze.

I am not sure how overpowered it would be - any bonus beyond +4 would require a Kerbal who has went to LKO,Mun,Minmus and Duna/Ike or a Jool mission (level 4). For example, landing a level 2 Kerbal on the Mun would give you +2(3.5) +7 science, +7 rep or +7000 funds for the landed EVA report. It is enough to notice, but not too much. I think surface samples should be mostly as-is, since they are examined on Kerbin. Basically, the Kerbal is told what to collect and brings it back in a bag. Reports are done on-site and are supposedly what the Kerbal notices.

It would be useful to have crew/eva report science rewards scale with Kerbal experience. Surface samples and experiments should be nearly constant, as they are processed at home. A possibility: Pilot Crew/EVA Reports: Give reputation according to experience (+ base science yield) of +0, +1,+2,+4,+8,+16, times science multiplier... think Neil Armstrong, etc Engineer Crew/EVA Reports: Give bonus funds (+ base science yield) of +0,+1000,+2000,+4000,+8000,+16000 times science multiplier...symbolizes industrial applications of observations, etc. Science Crew/EVA Reports: Give bonus science (+ base science yield) of +0,+1,+2,+4,+8,+16 times science multiplier, representing superior report quality and observations. Make it rewarding to send high level Kerbals to get information, and allow the Kerbal selected to give a different class-based rewards useful in career.

What I used to do was take the starting and ending TWR for each Kerbin launch stage, subtract 1, and average them. This gives you a linear approximation with a good over-design margin when you are spending time burning horizontally higher up. As Jeb says: "When in doubt, use more boosters. Put boosters on boosters. Use tweakscale to make bigger boosters. Then, use KJR so they don't fly apart. Put a command seat on the final stage, preferably also a booster."

If you have maneuver nodes unlocked I recommend going to Minmus before the Mun. It takes only another 100m/s of delta-v but the gravity is much weaker, letting you land or change your orbit using much less fuel. Believe it or not, a kerbal can easily jetpack from orbit to Minmus' surface and back up to orbit, especially from the highlands or midlands. If you have the funds, unlock surface samples from the level 1 science upgrade. You can get one from every KSP and Kerbin biome and they give you considerably more science than the normal temperature/pressure readings. Also, if you have the OKTO don't worry about returning science. Just transmit for the 50% from Minmus or the Mun - that will give you enough science to unlock the 2.5m engines+tanks and give you the power needed to send manned return missions.

The orbital science lab works in orbit, on the surface, or even flying through the air if you have enough stuff attached. You collect data from normal science experiments (it is separate from "science" - you can get data once from everything, even if you have already cleaned the science points out) and spend electric charge to store it in the lab. If you have at least one scientist in the lab (2 is better) you can use electricity (about 4 a second) to slowly convert the data to science. 5 data points will eventually get you one science. Higher level Kerbals get you science faster. Once you fill up (at 500 science) you stop getting more, but you can transmit what you have at any time. You can basically get infinite science this way - a mission to LKO and HKO and the Mun or Minmus orbit can get you 2500 science from the data with plenty of extra experiments available. The hard part is getting a 3.5 ton 2.5m part into space - you need a pretty heavy launcher and it is hard if you don't have the mainsail unlocked.

I find that clusters of 3+ are stable, but one or two engines has a habit of falling more often than not. It does seem like rockets are a little less stable on the pad than you would expect with symmetry enabled.

MOAR BOOSTERS!!!!! Seriously though, you do need engines of some type. If you docked a cluster of fuel tanks and a NERVA you could probably get that to the Mun, Minmus or even Duna/EVE orbit with enough fuel. The acceleration is small enough to mitigate structural risk, while unlike ions you will actually see your velocity meter moving. You can set it up with a mobile processing lab and move it from SOI to SOI as you run out of data.

In RSS you get no science from the surface of the earth - I am pretty sure that is intentional. You have a lot more science instruments though (Geiger-Muller, Micrometeorite and Telemetry Scan for example) so you get more once you launch something.

Now that you mention it, I would like to see some cluster-type engines in stock KSP. Cluster 4 Reliants together, give them a thrust bonus and a little less weight overall and say that the Kerbals took a mainsail turbopump and hooked it up to 4 Reliant chambers. 4 1.25m engines would make a perfect 2.5m part, potentially with higher TWR and efficiency than the skipper or mainsail at the expense of raw power. Also, in RSS that RD-171 is insane. Makes the F1 A/B look like an old pile of junk.

Assuming you have the KSC relocation mod, you can change your launch site using the tracking station. On the map of Earth/Kerbin you should see a bunch of small rocket icons - click one to move your launch site. Your KSC relocates, keeping all upgrades.

The solution I advocate is introducing upgraded versions of the Terrier and Reliant. The vector is basically a swivel on steroids (more gimbal, thrust, etc) - there should be a Vactor derivative which trades the gimbal for mass/thrust and a Vacuum engine with about 400 ISP.

When you use "Vectors" as attitude control jets.

Flying wings are aerodynamically unstable. Continuous 3-axis control input is required to maintain level flight. The B2 stealth bomber had independently controlled engines which varied their thrust output slightly to act as yaw controllers, in addition to the pitch and roll control you can get through thrust vectoring and control surfaces. Since you are stuck with pitch + roll only ( at least using SAS - a mod or manic mouse clicking could allow differential thrust to some extent, although it would be funny to watch and probably would not work) you end up having difficulty controlling your aircraft. You might be able to get around this using Vernor engines as RCS thrusters - they point outwards (so near-nose placement gives you decent yaw torque) and they are quite a bit more powerful than standard RCS thrusters. Since you need RCS for spaceflight anyways (if you want the SSTO route) I would recommend using a couple and trying it out. 50+ tons may be pushing it a bit, but you should be able to stay at least somewhat stable with SAS working with your jury-rigged 3-axis control. In short, you have 3 degrees of freedom with 2 degrees of control, meaning that no matter what you do something is going to mess you up eventually. It would be a nice challenge though - "make it to the island airfield with no vertical lift or control surfaces."

My technique was to use struts to attach the widest parts of the rover, attached to mini-decouplers so I could get rid of them in space. You could also put a 2.5m rover on top of a 3.75m stack - at that point the aerodynamic profile should be less important as you have a lot more connection strength and thrust to overcome air drag.

I usually just put an ISRU and mining drill + ore tank on any lander intended for another planet. You only need one small tank (you can just use the ore and re-fill it) and the weight is not that big of an issue as you basically half your fuel requirements for non-atmospheric bodies. When it comes to launch, I just make it as draggy as I want, and launch it nearly straight up at a low TWR to start. This minimizes drag losses and only takes a moderate investment in extra delta-v.

That far out, hydrogen would condense to a liquid if it had that kind of density. Hydrogen boils at 20k (13.8k triple point), so outside of 100AU it would liquefy as long as the pressure is more than 7.04 kpa. Unless the body was big enough to have significant internal heat, you would not see a hydrogen atmosphere at that distance. Most likely, any object that formed in the dwarf planet (say < 0.1 Earth Mass) range would be too close in to capture any hydrogen, then ejected to a distant orbit where the gas density is basically zero. I don't think the universe is old enough for liquid hydrogen planets - you would need a gas giant to eventually cool completely and have it in interstellar space or around a black dwarf.

With respect to frame rate, I seem to have trouble based on the rocket mass, not the number of parts. Usually the majority of specific parts are on or near my payload state (I use procedural for fuel tanks). When my rocket gets into the 1000+ ton range (one shot 5 tons to Neptune FTW) the game slows down, as if it can't process the physics fast enough. By the time I decouple my first stage the game is speeding up, as I have burned away most of my mass. Once I get to second stage separation the game is basically at full speed. In RSS/RO your launch vehicles are a lot larger than in stock - if the game is modeling rocket parts using some type of mass or size based mesh then larger vehicles will lead to problems.

Hello Everyone, I just tried to skim the upper atmosphere of Neptune from a somewhat eccentric orbit (700km x 1.25M km). I figured with an atmosphere height of 700km I would be safe with a Perapsis of 691km. Instead, my probe instantly exploded. Literally - it blew up at 699,992m. Should the atmospheres really be set up as a brick wall? Granted I was traveling at 22 km/s (3 times orbital speed for earth) but still - 8 meters?? Is there some kind of rounding taking place right at 700km? I figured there would be a curve function with a root at the atmosphere edge, do you guys instead decay the exponential from 0 ASL and then chop off whatever is left? It seems strange to me - using Neptunes scale height of ~20km, the atmospheric pressure at 691km would be 10^-15 times the ASL pressure (34.55 factors of E is about 15 factors of 10). Even with a 3000 atmosphere surface pressure (which is also wierd - isn't the surface considered the 10 bar level for diameter purposes?), you would have only 3.33*10^-11 atmospheres at that height. That would be the equivalent of Earth at 215km, assuming a scale height of 8.5 km. Does the game take earth's 130km pressure (2.283 * 10^-7 atmospheres) and interpolate that to the atmosphere top for everywhere? I could understand getting re-entry heat at 22 km/s with 10^-7 atmospheres, but 3.33 * 10^-11? Anyone know what is going on here? Thanks, Max

For most reasonable transfers, the difference between "exactly on" and "about a week off" isn't huge - on the order of a couple hundred m/s of delta-v on both ends. The delta-v requirements are non-linear functions like parabolas - you get a broad trough with increasing slope when you get farther off the optimal point. My solution in stock was to use the ion engine with a couple gigantor solar arrays - you get enough delta-V to correct almost anything. If you are operating near Jool/Eeloo you will have trouble powering the ions, but for Duna/Eve/Moho you can usually transfer and enter orbit easily. Landing needs chemical rockets (except for Gilly or maybe Minmus if your probe is really light) but orbiting with ions is fairly easy.

Is there a way to negate all liquid hydrogen boiloff? I tried using active radiators and a cryogenic tank but I still lost everything within a couple months. I wanted to use a radioisotope rocket for probes and need liquid hydrogen for fuel.

Transfer windows are periods where the alignment of your launch site and your destination allow low-energy, short period transfer trajectories. For example, Kerbin to Duna: [B]Kerbin and Duna both at 12 o'clock[/B] 1. You need to burn the delta-V to raise your AP to Duna's orbit 2. When you get to your AP, Duna isn't there. Since it was on a higher orbit, you passed it a month ago. 3. Revert Flight 4. Burn the delta V to raise your AP past Duna's orbit. Now, when you reach Duna's orbit, you are ahead of Duna. Duna catches up to you while you are outside. If you time it right, you fall back through Duna's orbit while passing close to Duna. 5. You enter Duna's SOI with a velocity of 5 or 6 km/s and fly off into space. 6. Revert Flight 7. You make 4 or 5 burns to gradually raise your orbit, until you eventually reach Duna with reasonable velocity. 8. Your Kerbal's Grandchildren land on Duna [B]Kerbin at ~10:30, Duna at 9 o'clock (Rough Transfer Window assuming CCW orbits) [/B]1. You need to burn the delta-V to raise your AP to Duna's orbit 2. When you hit Duna's orbit, you enter Duna's SOI. The head start Duna had at launch compensated for your lower orbit. 3. Since you are only moving slightly slower than Duna, you don't need to burn so much fuel to enter orbit Basically, transfer windows let you get to another planet in half an orbit (for Hoffman) or one orbit (Bi-Elliptical). Otherwise, you need to do a resonance drift (set it up so that after 4 or 5 orbits you meet your target) or expend a lot of radial delta-v to shift your orbit in flight. If you have over-engineered rockets, you might just be doing hyperbolic transfers, where your orbit goes out way past your target but you meet in the middle. This is what probes like New Horizons did (with a gravity assist) to reach the outer planets in a reasonable time. However, if you want to enter orbit or land without wasting fuel you need to use a transfer. You can get away with flying all willy-nilly "Jebsplosion style" but it makes Bob and Bill nervous.

I had the problem on mars - I just went to space center and back and the lander was re-situated on the surface.