smartech

I think this is a very useful chart for the atmospheric planets: Eve, Duna and Jool. Unless we are we have a massive delta-v budget, for the rest it is almost always better to aerobrake into a highly elliptical orbit with a periapsis barely above the atmosphere and apoapsis as close the edge of the SOI as possible around the closest atmospheric planet and wait for a good transfer from that orbit.

A very good solution to waste is to throw it into a mini black hole. It will be converted to gamma radiation as the small black hole evaporates.

Tides would make a wonderful gaming experience. Imagine being safe to land only above 500m ASL because otherwise your lander/rover/base gets washed away and destroyed by a giant tidal wave. Must collect the beach science very quickly before the next one comes. Maybe wait for a particularly large ebb so that more science from the bottom can be collected. Extra science for surf-boarding. - - - Updated - - - Maybe even once in a while a dead Kraken would wash up and you can study it only before the next tide collects it back into the ocean.

There was a similar challenge before, but I cant find the link. I think the winners managed upwards of 33km/s. Edit: here it is http://forum.kerbalspaceprogram.com/threads/59823-0-22-0-23-0-Delta-V-Maximization-Challenge

I've played around with the optimal rocket tool here: http://garycourt.github.io/korc/, and it looks like Foxster has pretty much nailed it, so the challenge is basically over . The lightest SSTO it finds with 4500m/s is 0.682t. Interestingly, going to multiple stages it goes down to only 0.652t with 2 stages because the decouplers are very heavy relative to the rocket.

Here is Tough Bird Special Edition landed on Duna after a reentry from Laythe. Unfortunately I did not capture screenshots during parachute descent. The last 2-3 pictures show them deployed (black covers) and the rear vernor trusters firing to stabilize after it bounced off the surface. The last image is right after takeoff. Posted originally here: http://forum.kerbalspaceprogram.com/threads/33312-Showcase-SSTO-s!-Post-your-pictures-here?p=1643625&viewfull=1#post1643625

I cant wait for the day when we'll be able to truly colonize the Kerbal system. Imagine landing a large supply ship on Laythe, unloading a small base to let you do small repairs (re-tile fuselage after re-entry, re-attach fallen parts?). Make a small runway, upgrade it with lights for night landings, then make a larger runway. Make an assembly building to launch rovers. Bring a terraforming (Kerbin-forming) machine, gradually gets green, some water evaporates as it gets warmer and there is more land with trees etc. Maybe then Laythe will be more interesting. Right now for me the only interesting thing about it is how to get there and back with the least amount of delta-v.

I recommend reading those wonderful charts optimal engine choice for desired TWR and delta-v. Generally, the LV-N is usefull for bigger craft with lots of fuel, which would ammortize its large weight.

Minmus is interesting because you can use the Greater flats as long runways to accelerate to orbital velocity, and you dont really need TWR > 1.

Happy New Year everyone. Today I'd like to share Tough Bird Special Edition: now able to visit Laythe and Duna on the same trip. As usual it is stock physics and 0.25 parts. This is based on my previous effort here: http://forum.kerbalspaceprogram.com/threads/33312-Showcase-SSTO-s!-Post-your-pictures-here?p=1626216&viewfull=1#post1626216 It's now opened a new category: SSLDRRV (Single Stage Laythe and Duna Roving Return Vehicle). It basically means it is capable of performing the trip Kerbin-Laythe-Duna-Kerbin in a single stage. There are some differences from the previous design: * the delta-v on rocket power is up to 6.7km/s to accommodate the takeoff from Duna, the payload is down to just 10 kerbals to maintain the needed mass fraction. * overall, along with its jet engines, the craft now expels nearly 20km/s delta-v. * there are more wings in the front part * hard to see in the pictures, but there are extra vernor engines in the rear in order to stabilize the craft after bouncing off the surface of Duna after the initial parachute drop. The landing on Duna itself brings several challenges. Because of the thin atmosphere, the craft can only land in the lowlands, no more than around 600m ASL in order to limit the descent on parachutes to 21m/s and the takeoff speed to 35m/s. Of course given enough time, it can go pretty much anywhere on the planet as it can rove around freely when landed. The landing at such a speed becomes problematic as it creates a large bounce back in the air, and that's where the extra vernors come handy. I set Mechjeb to maintain surface horizontal shortly before the touch-down, and it uses the vernors and the momentum wheels (which by themselves are too slow) to righten the craft back wheels down after the bounce. For a takeoff at 600m ASL on Duna, I first accelerate using the roving wheels to 20m/s, then engage the rockets to push further to 35m/s which should be enough to lift the nose off. The takeoff speed is not particularly high, but because of the weight of the craft at this point, it is difficult to attain it quickly. Given how the surface of Duna is riddled with small hills, high takeoff (or landing) speed is a real killer for any spaceplane. Down on the surface it has 2.7km/s delta-v. At this point of the trip, the craft has 0.56 TWR before takeoff and it climbs to 0.72 right after orbit circularization. Yes, a craft with TWR less than 0.72 can make it all the way up to orbit! After around 15 minutes of ascent while pitched up 25 degrees, after burning through 1.9km/s, it attains 45x45 low orbit with 850m/s left for the trip back to Kerbin. Pictures from Duna ascent here:

Suggestions: 1. You probably do not have either enough thrust or enough lift or both. A good rule of thumb is 15t per jet engine, 13t for RAPIER. and go to slightly more loading (17-15) when you get this working. 2. It could be hard for a large plane, but try to calculate the total lift rating of the parts and make sure it is around 0.8-1 lift rating per t. 3. Make sure the center of lift is slightly behind the center of mass (the spheres should touch or nearly touch), and the thrust vector is pointing towards the center of mass. 4. Install more control surfaces: canards near the nose of the plane, elevons near the rear. Make sure the canards are facing the right way or they wont work.

Improved version of my SSLRRV Tough Bird. The plane has stock 0.25 parts and physics. The album has pictures of a trip to Laythe's rarely seen north pole. The parachute landing was completely unnecessary since it turned out to be completely flat, although I did not know what to expect in advance. Improvements: * 50% more payload: now 26 kerbals can make the trip to Laythe and back * weight is down 12% to 207t, while still maintaining 6km/s delta-v. * more robust plane because of the weight decrease with the same 10 landing gear, 40 roving wheels, and 18 radial parachute system. Survives up to 18m/s drop full of fuel (only needs tire repair). The main improvement is going from 16 to 12 jets, which allowed me to eliminate a lot of fuel while maintaining the same mass fraction. I had to improve my ascent profile, and add some extra wings to compensate for going from 14t to 17t per jet engine. The lighter weight in turn enabled me to eliminate 1 atomic engine, now down to just 3. The plane has pretty low TWR: 0.66 on jets during takeoff, 1.38 maximum at 1km/s, just 0.1 on atomic engines initially, but it is perfectly sufficient to reach Laythe and back to Kerbin atmosphere, still have 2km/s left on atomic engines and capable of flight for another 5 mins on jet power. The low TWR necessitates the use of "stretching" burns, which raise the apoapsis nearly to the end of the SOI. To depart from Kerbin orbit to Jool, I first set up a maneuver node for the ejection burn (2.2km/s in my latest trip), then "stretch" the orbit to around 8000x100km just inside Mun's orbit (inside its SOI) keeping the periapsis exactly on the maneuver node. This sinks 850m/s, then I create a new maneuver node which should fall near the periapsis with around 1.2km/s. Then 8mins before the maneuver I start burning pro-grade for nearly 17minutes to attain the delta-v. I perform a similar stretching orbit when departing from Laythe. There I sink 600m/s in the SOI and complete the ejection with another 700m/s. Original plane info is here: http://forum.kerbalspaceprogram.com/threads/33312-Showcase-SSTO-s!-Post-your-pictures-here?p=1555016#post1555016

But rearranging does not litter, given all the parts are re-docked.

Can you design a ship that will split itself into parts and attach to the asteroid as wings, tail and landing gear, and land the whole thing on the runway? For that matter, if a craft reconfigures itself through docking, does this still count as a single stage?

This craft is built to primarily fly in space to Laythe and back, but it still qualifies as a rover: Original post here: http://forum.kerbalspaceprogram.com/threads/33312-Showcase-SSTO-s!-Post-your-pictures-here?p=1555016&viewfull=1#post1555016

"Tough Bird": a bigger better faster and stronger SSLRRV (Single Stage Laythe Roving Return Vehicle) 0.25 stock parts and physics used (Mechjeb for control). Flies 2 pilots and 16 passengers to Laythe, roves, takes off and back to Kerbin. (possibly more roving on Kerbin if lands far from KSP). Cost: 693805.5 credits. Posted originally here: http://forum.kerbalspaceprogram.com/threads/33312-Showcase-SSTO-s!-Post-your-pictures-here?p=1555016#post1555016

Is it a plane? Is it a rocket? Is it a rover? Here is "Tough Bird": a bigger better faster and stronger SSLRRV (Single Stage Laythe Roving Return Vehicle) 0.25 stock parts and physics used (Mechjeb for control). Key parameters: * 6km/s delta-V from orbit on rocket power. * Enough fuel to ascend from Kerbin and then from Laythe. * 2 pilots and 16 passengers traveling comfortably inside the vessel. (880 credits per passenger for fuel). * 40 wheels enabling roving activities. * 22 radial parachutes. Descends at 14m/s at Laythe on a typical mission. Sustains no damage up to 17m/s with full fuel load (see album) * 16 turbojets and 4 LV-N atomic engines. 22 vernor engines to shorten takeoffs to 70m/s. * 98 ram air intakes. * 229t starting mass, 140t fuel (approx. 2 S3-14400 tanks) Typical mission profile: 1. Take off from KSP, ascend to 22km altitude. pitch less than 55 degrees. 2. At 22km accelerate from 750m/s to 1200m/s (orbital) to use the highest thrust level. 3. Resume climb at 50m/s to 28km altitude, then 30m/s to 31.5km. 4. At 31.5km slow acceleration from about 1950m/s to exactly 2260m/s. 5. Pitch up 30 degrees, engage rockets, switch off engines sequentially in 4 groups as oxygen runs out and throttle drops to 2/3. 6. Circularization burn (less than 30m/s) and target Jool: ~2100m/s 7. At Jool: aerobrake or target Laythe directly. Approximately 500m/s for aerobraking, orbital insert and de-orbit maneuvers. 8. Atmospheric entry and glide to relatively flat land near sea level. 9. At least 1km above terrain: drop velocity to under 70m/s and deploy parachutes to avoid ripping fuselage off. Transfer fuel if pitch or roll above 5 degrees. SAS and brakes on, deploy landing gear. 10. 14m/s drop on terrain. Repack parachutes, repair wheels. 11. Rove! Retract landing gear, enable wheels with action group. Fine controls on, speed below 10m/s to avoid breaking wheels or ripping fuselage supports. 12. Position on a relatively flat terrain facing east, the plane needs 350m (about 1/7 of KSP runway) for takeoff with the amount of fuel remaining. 13. Rebalance jet fuel. Deploy landing gear. Brakes on. Jet engines on. SAS and RCS on (for vernor engines). When jets spool release brakes. At 65m/s pitch up, in the air switch off RCS. 14. Climb to around 15km, accelerate to 1500m/s then continue at 80m/s ascent. 15. At around 24km engage rocket engines and climb at 30deg. Switch off turbojets with action groups in sequence. 16. Short cirularization burn. At this point: at least 3km/s delta-v remains. 17. Target Kerbin, and either land at KSP, or parachute again. When nearly empty the plane glides happily at 18m/s and parachutes at 10m/s. "So why is it so big?" Because it has a large delta-v budget, and carries essentially a 10t payload (cockpit + 4 passenger segments) on a round trip to Laythe with complex capabilities. It was a very tough plane to build and test because it is initially underpowered and has a very thin margin for error during Kerbin ascent, although it is much easier to fly afterwards. A great challenge was to make it robust for parachute drops without using too many parachutes.

Here is new SSLRRV vehicle concept here: Single Stage Laythe Roving Return Vehicle. It has several unique parameters and features: 1. 6 km/s delta-V from orbit on rocket power 2. Enough fuel to ascend from Kerbin and then from Laythe. 3. Can move around as rover since it has 10 wheels in addition to landing gear. 4. Has 12 radial parachutes and can descend down to the ground at around 10-12 m/s below 2km altitude. While glide-landing on Laythe is possible, it is a bit tricky to land on some of the rocky islands near the equator. The parachutes obviously make this problem go away, plus there is no need to even turn on the jets. After landing it is easy to position down a straight path for takeoff.

I think I have a Laythe round-trip design: 5.8km/s delta-v with 30% fuel remaining after ascent from Kerbin, and 6.3km/s with no jet fuel. Laythe ascent is pretty easy by comparison because the plane will be substantially lighter and the lower gravity as well. The design grew to 38 ton start mass. I moved the LV-N engine more in-board and it can land at a much higher angle. Unfortunately I can't find a way to keep the extra 4 passenger compartment without sacrificing too much delta-v. With 4 passengers/6km delta-v will probably need a substantially bigger ~50t plane.

Hi, First time poster here, and I thought I'd share the SSTO I've built recently with the .25 update. It has a quite ambitious goal: SSTO to Laythe, land on Laythe and get back to Kerbin. Some specs: * weight 33tons * cost 120k * 4 turbojets, TWR 1.36 on Kerbin when full. * 4 mk1 fuselages with jet fuel * just one atomic LV-N rocket engine to get to orbit and maneuver in space * mk2 lf+0 small and large tanks, plus one mk2 adapter to 1.25m on which the atomic engine is mounted * 3 FL-T400 and one Fl-T200 inside mk2 two cargo bays. * passenger module for 4 additional seats just to look cool * docking port * mods used: Mechjeb, Hypededit, Alarm clock Launch to Orbit from Kerbin expends around 45% of the jet fuel. Only about 550-600 m/s delta V needed from the atomic engine, but the ascent is a little tricky because the atomic motor gives only 0.20 TWR After orbit, it has about 3.8 km/s delta V, which *might* be enough to get to Laythe and back, although I probably need to optimize the design a bit more to get to perhaps 4.5km/s (replace the passenger compartment with fuel for example). I'm also considering dropping off the FL-T tanks in the cargo bays after they are expended (not 100% reusable, but close enough). I've tried hyperediting onto Laythe, and it uses around 35% of the jet fuel for ascent, with around 300m/s delta v. Considering it will need some just fuel for maneuvering on Laythe and Kerbin, I think the jet fuel should be OK. Here are a few pictures. In the VAB Picking up speed on the runway. Rotates at 105m/s Steep ascent At 18.5km: At 24.5km At 27km At 31km, Mechjeb is throttling down the engines Turned off the outer 2 engines, and engaged the atomic engine. At 35km, Mechjeb throttles down the engines. Unfortunately it also means the atomic engine is throttled down as well, but it is still good for orbit. Turned off the remaining 2 turbojets at arond 1/3 throttle. At this point I'm picking up speed VERY slowly. 40km and on my way to orbit! Note 0.19 TWR in the Mechjeb screen below. Getting dark, but orbit is very close. 64m/s circularization burn In orbit, with 3.6km/s delta V, and 55% jet fuel remaning Opened all cargo bays Test landing nearly full of fuel, 5m/s descent. Touch down, around 2-3m/s descent Heavy braking, the nose comes closer to the ground Safely landed