sevenperforce

Every time.

Paging @Ultimate Steve, @IncongruousGoat, @Wanderfound, @qzgy, @Kergarin, @macktruck6666, @Earthlinger, @ShadowGoat, @Thor Wotansen...

The invention of Debug Drive (pioneered by one Cheiter "Alt-F12" Kerman) has rendered the complexities of orbital mechanics virtually obsolete. Now, spaceships can simply turn on their Debug Drive and zip almost instantly from any orbit to any other celestial orbit, without consuming a single drop of propellant. Some have decried the use of this technology as "too easy", but most have embraced it with enthusiasm. The new tech has only one limitation: it can only be used once a stable orbit has been established, as the Tunnelizer Particles used by the drive will rip the ship apart if exposed to too much gravitational imbalance. So while orbital mechanics is no longer a concern, rocket science remains alive and well. THE CHALLENGE: Build a ship capable of deorbiting and orbiting at many worlds as possible, without refueling, staging, or docking. Your ship is only responsible for the deorbit and orbit; it does NOT have to perform transfer or capture burns. You may use the Debug Menu to "jump" from any stable orbit to any other stable orbit, but you cannot jump from the surface (or from a suborbital trajectory) to orbit. Your vehicle must be manned. At no point can any parts explode, break off, or otherwise leave your ship. Absolutely no part mods. This challenge is about design, so you do not have to fly your ship into orbit; you start the challenge in LKO, fully-fueled. You decide what order to visit worlds in. SCORING: You gain points each time you land and reorbit from a given world. Each world is worth a certain number of points as shown below. Gilly: 6 Pol: 26 Minmus: 36 Bop: 46 Ike: 78 Dres: 86 Mun: 116 Eeloo: 124 Duna: 145 Vall: 172 Moho: 174 Laythe: 290 Tylo: 454 Eve: 800 (if anyone can pull it off) Good so far? Don't get started just yet. You can earn bonuses based on vehicle design and mission parameters. Each bonus is a 10% increase to your final score, and they multiply, so two bonuses means a 21% increase, three bonuses means a 33.1% increase, and so forth. OP reserves the right to add new bonuses in the future. Homeward Bound: Return to the surface of Kerbin from LKO at the end of your mission. Infinity and Beyond: Your vessel consumes neither xenon nor ablator, meaning it could conceivably refuel at any ISRU station and continue its mission indefinitely. In the Neighborhood: Visit each planetary system only once. In other words, you complete all landings within a given system before moving on to the next one. Baby Grand: Visit every world but Eve. Kerbin's Sweet Caress: Land within visual range of the KSC at the end of your mission. No Surly Bonds: Your vessel is capable of SSTO from Kerbin, independent of your main mission. Rocket Scientist: Be the first person to post, in this thread, an accurate explanation for how I arrived at the scoring for each world. Hera, Wife of Zeus: Land on all the moons of Jool. Powerhouse: Your vessel carries no solar panels. Disembark: Your Kerbals can leave the vessel and plant flags on every world without needing their jetpacks. Regular Ace: Fly the entire mission without relying on informational or piloting mods. Pickup Artist: Your vessel is capable of EDL at Eve and re-ascent to orbit if Infinite Fuel is enabled after landing, independent of your main mission. One Stop Shop: Your vessel consumes only a single type of propellant (e.g., xenon only, LF only, monoprop only, or LFO only). Killing Me Smalls: Your vessel has the lowest dry mass of any submission. To qualify, you must land on either Laythe or Tylo. Rule of Cool: You have a dual-thrust-axis lander, capable of vertical takeoff and landing perpendicular to your main engine thrust vector using dedicated engines. Good luck, everyone! LEADERBOARD: @Wanderfound Touches down on Laythe and the Mun before coming home to Kerbin for a pinpoint KSC landing. For now, the smallest submission capable of Laythe, so 791 points!

Oh, definitely. It would be a "You thought landing on Eve was a piece of cake? Try this" situation. But it would actually be possible, unlike Jool, which is instant death no matter what. Another thing that would be neat (and incorporate a little of the real-solar-system ice giants) would be to make the planet's rotational axis and its rings VERY heavily inclined, further complicating missions.

A gas giant with rings would be really neat, particularly if the rings had interesting/useful properties. For example, the rings could have a small ore concentration, so that Convert-O-Trons could operate without an ore source while flying through the ring. Or the rings could be the only source of xenon outside of Kerbin. One of the bad things about adding another gas giant is that it's yet another planet you simply can't land on. This could be remedied if, rather than modeling it as an atmosphere of infinite depth with gradually-increasing density, it was modeled as a thin, high-density atmosphere on top of a low-density ocean. This would enable you to land and take off again, if you have something low-density enough that you can float with it. So it would be less gas giant and more ice giant.

By my count, you would need 17.2 km/s of dV to visit every single world (excluding Kerbin, Jool, and Eve), assuming that you use aerobraking for free EDL at Duna and Laythe. The inherent tankage mass ratio in KSP means that an infinitely large ship powered by nukes cannot exceed 18 km/s of total onboard dV, but since you could conceivably use ions for landing on some of the smallest worlds and you can use jet engines on Laythe, it MIGHT be possible to hit them all.

Right. From orbit to surface and back, as many worlds as possible, no docking/staging, no ISRU, jumps between orbits are free. The rules don't apply to getting off Kerbin in the first place, of course. (One could imagine a future in which cheap, lightweight, reactionless warp drives permit rapid transit between planetary orbits, but can only be used in a stable orbit due to gravitational effects or somesuch. In such a world, you'd want your Everywhere Ship to be able to visit multiple planets in a single trip.)

Thanks! Trying to figure out where I could or couldn't land got me thinking...would anyone be interested in a Future SSTO competition, where the goal is to land on as many bodies as possible, in a single stage, without refueling, but with free transfers? In other words, you are only designing the lander, not the transfer vehicle, and you don't have to worry about the transfer or capture burns. Alt-F12 the vehicle into each desired orbit in turn. Interesting?

Made it. Eve, Gilly, Minmus, and orbits around Kerbin, Kerbol, and the Mun. 98 parts at launch. Partial album below. Let's see. That should be good for, what...1820 points? @Ultimate Steve@Earthlinger

Another thought: what about leaving Gilly for a Kerbin gravity assist to Duna/Ike orbit, then back for a Minmus landing and Mun orbit? What kind of dV would that take? The SAS assumes all engines point roughly through the CoM and gimbals accordingly. With a tight cluster, this is a sufficient approximation, but with a really wide cluster like that one, it causes problems. An engine on one side will have a different gimbal-induced vehicle torque than its opposite, since there's a brief instant where the moments of torque are in opposition. So yeah, turn down the gimbal range on the outer engines. The center one can have full gimbal range. Or, if you really want to get fancy, go into the advanced tweakables and turn off pitch authority for the dorsal and ventral engines (relative to your control module's navball), and turn off yaw authority for the port and starboard engines. Keep roll authority on, of course, as the core engine has no roll authority at all, simply by physics. Pitch and yaw in a cluster is better (more efficiently/reliably) controlled by differential throttling than by gimbal, but unfortunately KSP can't do that.

Let's see...I have 7100 m/s of dV left, and I'm in Gilly orbit. Is that enough to transfer, orbit, and return from Moho, and still have reserves for Kerbin orbital insertion and a Minmus landing? If not, I'd get more points for simply going straight back to Kerbin and hitting Minmus and a Mun orbit.

I originally tried with regular structural panels and they went bam every time.

I'm 2.33 tonnes in orbit around Gilly (my Kerbal is EVA'd down to the surface) and I have a single Dawn. Moho should have plenty of power but the Dawn still peaks at 2 kN, so with Moho's 1/3 gee gravity, I would have to be under 0.74 tonnes to get a TWR>1, so that's a non-starter. Of course, I could get really clever and do a suborbital catch using EVA as my descent/ascent stage, but that's too tricky for a "just one try" approach. Running a single SP-W 3x2, which gets 3.4 EC/s at Gilly, so it will get a maximum of 0.8 EC/s at Ike. This limits the effective continuous thrust of the Dawn to 0.43 kN, meaning I'd need to be down to 0.4 tonnes to get a TWR>1. So that won't work either. Minmus, of course, is easy enough. Should at least be able to make Moho orbit before coming back. Without good TWR I don't want to risk the Jool system.

Also, since I'm using ions and solar for my return stage, Dres and Jool are probably out of the question. Maybe Ike too; I don't know.

Gilly should be easy enough. I'd like to pick up Moho, Ike, Minmus, and the Mun. Not sure whether Dres is possible.

Update: off Eve, down to six parts, and only 9,020 m/s of dV left in the tanks. Where shall I go from here?

Well, the launch vehicle itself was only 15 parts. Transfer vehicle is 3 parts. Entry, landing, and ascent vehicle is 73 parts; return vehicle is 7 parts.

I kind doubt this, but feel free to prove me wrong Working on it. Currently in Eve orbit, entry and landing vehicle intact, with a LOT more dV in my transfer vehicle than I had expected.

At least 18.

Right, I meant at launch too. Under 100 parts. Eve, flag, back.

Hardly. Heck, just for that, I'll do it in under 100 parts.

Simply getting to Eve's surface and back, successfully, would earn...let's see...1520 points.

I did that once for a Sea Dragon challenge, before I understood buoyancy in the Kerbin oceans. Assembled the rocket in the SPH, drove it out into the drink with rover wheels, decoupled the rover wheels, then used pairs of Hammers at the fore and aft ends to flip vertical before staging to release the Hammers and ignite the first stage. Took a lot of doing, but I managed it. Of course, that's not the most reuse-friendly architecture, especially when you have to assemble it manually. In testing the two different architectures I've attempted so far (Energia-style with parallel staging, and Stratolaunch-style with a winged second stage), I relearned the importance of vertical thrust on Eve. I had thought that using a winged vehicle would enable takeoff with TWR<1, and it does, but rocket engines are so inefficient on Eve that you don't really climb appreciably before your mass drops and your TWR is enough to just point radial-out and be done with it. So it would seem the primary advantage of using HTOL is "free" crossrange/landing and presumably easier vehicle mating, but nothing really in the ascent department, since you need to be pointing radial before any actual progress is made. VTHL would have the same advantages with none of the disadvantages, but getting it erect would be very challenging. And we still have to make sure the first stage is beefy enough to have the dV for significant suborbital hang time, or there's no way to get the second stage orbital and switch back in time.

All right, she's done, and I tested the ascent. Launch mass of 490 tonnes, payload of roughly 90 tonnes, enough LF for at least 18 round-trips. LF is the limiting factor; I packed enough xenon for 64 trips, so I will definitely run out of LF first. A sneak preview:

I've already tested the assembled LV on Eve using the cheat menu. My initial first-stage booster (with the second stage slung alongside, Energia-style) wasn't quite big enough to get a high apoapse, but that just means I need to go a touch bigger. The upper stage makes orbit without too much trouble. No way you can recover the side boosters in stock. A VTHL core stage, using the oceans to go vertical for launch, is one promising architecture I hadn't considered. See, this is why I made a challenge out of it!