Mephisto81

Thank you for the detailed explanation! Getting the reusability was the issue at hand.

Does anyone her have an idea on how to either reduce the frontal plate drag of the shielded docking port or how to get a low drag junior docking port at the front with good heat resistance? I am trying to build some smaller SSTOs with docking capabilities. From my point of view, the best location for a docking port is in front, where the main engines on the back can be used for maneuvering. Foxster did some tricks with offsetting a fairing to reduce drag for a lander can at an Eve Ascent vehicle. But I haven't been able to replicate the effect.

Your Altair is a really sexy craft. Did you choose Aerospikes for aesthetics? And did you have any issues with exploding landing gear, if I may ask?

That is an interesting flight profile. Straight line is rather simple, if TWR is sufficient. 0.40 TWR sounds quite sufficient to me. And I second the part about drag. "Drag is king" I had crafts, which flew good and accelerated beyond the 400 m/s mark, but then a tiny bit changed and suddenly there was too much drag. This craft here is a good example, still scheduled for release in the next couple of days: This is a study, whether I can bring three Kerbals with a full science suite to almost anywhere in a lightweight plane. SSTA light, if you allow me to call it, powered by one rapier and one Nerv. Apart from getting the torque offset reduced by the Rapier and the Nerv, similar to some crafts from Turbo Pumped and Stratzenblitz, getting the drag down was an issue. Especially the service bays produced different amount of insane drag. Then, I realised that the drone core had to be put in front of the service bays, so that his slightly larger diameter can shield the bays behind from drag. Rearranged the order of service bays, drone core and science junior and ... the craft flew past 400 m/s again. No additional mass or parts, just rearranged the order. Another example of SSTO design margins is this one here, my beloved XR-02 Ranger. Inspired by the XR-2 Ravenstar from the Orbiter Space Flight Sim and the Ranger from Interstellar, it is one of my most efficient builts. This brick can land on Tylo and take off again whithout the need for a seperate lander, fly to the fiery depths of Moho. Only for Eve, I need an dedicated lander. As you can see, the take-off weight is around 89 tons, powered in atmosphere by only three Rapiers. This comes very close to my goal of 30 tons per rapier engine. The reason was to save engine weight, as Rapiers are mostly dead weight in space. For the weight of one rapier I can add two Skiffs, giving me much more rocket thrust and a higher efficiency (Rapiers have an Isp of 305 seconds, Skiffs of 330 seconds in vacuum). But now my TWR in atmospheric flight is only 0.36, which is a good part below 0.4. I had to really optimize the craft. The wings are slightly angled upwards, so the craft's body is more alligned with the airflow. This reduces drag. "Lift with the wings, not the body" All the open nodes on the outside are covered, no parts are sticking out. The different parts have been carefully checked in flight for drag. "Open nodes are draggy" Fun thing was, the frontal fuel tank, the 2.5m to Mk2, which I wanted for the looks, was producing insane amount of drag. Apparently, the fairing didn't register properly with it. Solution was to put a adapter plate right behind it. Suddenly, frontal drag was much more managable. The ascent profile depends on the Rapiers getting beyond 400 m/s at sea level, as the air is thickest and the thrust from the rapiers is the highest. After I got some speed, I can start to climb. With this low TWR, a straight line to orbit is not manageable for me. The rest of the way to space was easy. Mephisto (Attention span of a squirrel. Oh look, an SSTO!)

X-111 Universal Lightweight Lander https://kerbalx.com/Mephisto/X-111-Universal-Lightweight-Lander There was a question on the Interwebs for Duna lander pictures. The quite underpayed, but overstaffed design bureau of Mephisto Metalworks an Aeronautics decided to answer the call. The motto of the CEO for the day was "go big and go small". As nobody in the design bureau had a clue what the mad visionary ment, they just cobbled some fuel tanks, cheap engines and a chair together with a bunch of basic science instruments. Final part was the sacrifice of some snacks ( as no interns volunteered) to the Kraken, and with some real DARK MAGIC (a.k.a. the offset tool), the craft was real drag optimized as well. 7.3 t take-off weight, slightly over 5000 m/s dV. Takes one brave (or stupid, the line blures sometimes) Kerbonaut to the surface and back of most planets and moons in the Kerbol system. Tylo rated. and Duna tested. Has an initial TWR of 1 with full fuel tanks on Tylo. Last-minute add of a drogue chute and ladder. Mephisto (Can you use Ion Engines for cooking?) (Turns out, you can...)

And now, for something productive: Anuki Kerman is LOST IN SPACE. Naturally, Bill decided to design a brand new SPACEPLANE for the daring rescue mission. With clever book keeping tricks, Bill managed to get proper funding for the craft. Because space is big and scary, Bill decided to play it safe: 10 Rapiers, 3 Skiffs and 4 Nerv Engine would propel the 200 t craft. Just in case, the craft was build with a modest error margin: The craft was able to reach the outer planets or Moho and refuel with its ISRU. One can never know. 7000 m/s maximum range with only liquid fuel tanks should be enough. As the craft is quite overpowered, Bill was pondering, whether he should also include an Eve Lander at the front? Mini Tylo Lander in the cargo bay for later? And notice the fairing right behind the cockpit. In a later version, I might add an Eve Lander onto the front and build a fairing around it. A small cubic octogonal strut right behind the shielded docking port allows for part attachment to a shielded docking port. Normally, they lack attachment nodes. Will the craft suffice for a rescue from low Kerbin orbit? We will see... Mephisto (Insert witty one-liner here.) Airbreathing engines are much more fuel efficient than rocket engines. (Efficiency is often measured as Isp, the higher, the better) Therefore, every m/s you can get out of your airbreathing engines saves you oxidiser. Oftentimes, I fly quite lazy and only reach 1450-1500 m/s at that height. Rest has to be done by Rocket Engines until orbital speed of app. 2240 m/s is reached (from the back of my head) But most vacuum-optimised engines like terriers or Nervs, even Ion Engines, bring almost their full thrust there as well. So, if you have a spaceplane with rapiers and Nervs, you can switch on the Nervs when the rapiers are still breathing air at 18km.

Life goal achieved. People are confused.

I don't know his profile, but for most crafts I use the following: - gain speed close to sea level to get past 400m/s - gain some altitude to reduce drag (7-10km), getting more speed. - at around 20km craft should be flying at 1500 m/s, if possible even 1600 m/s - switch to rapier rocket mode, as soon as speed start to drop. - accelerate with rocket mode, until apoapsis is at 75km - turn prograde to reduce drag. - circularize close to Apoapsis If your craft has a really high thrust to weight ratio with rapiers, you can sometimes start your climb earlier. My Colibri has a take off weight off around 8 tons and a rapier. That is enough thrust to take off vertically. You just have to find the right angle on ascent, where you arrive at 1600 m/s on airbreathing engines without exploding at 21km above sea level. Rest of the ascent profile is the same. Picture of the Colibri:

X-112 Anuki SSTO Anuki Kerman is LOST IN SPACE. But fear not, rescue is underway! Naturally, Bill decided to design a brand new SPACEPLANE for the daring rescue mission. With clever book keeping tricks, Bill managed to get proper funding for the craft. Because space is big and scary, Bill decided to play it safe: 10 Rapiers, 3 Skiffs and 4 Nerv Engine would propel the 200 t craft. Just in case, the craft was build with a modest error margin: The craft was able to reach the outer planets or Moho and refuel with its ISRU. One can never know. 7000 m/s maximum range with only liquid fuel tanks should be enough. As the craft is quite overpowered, Bill was pondering, whether he should also include an Eve Lander at the front? Mini Tylo Lander in the cargo bay for later? With the main side tanks filled with LF/OX and locked, you still have 5.300 m/s dV on Nervs. What should Bill put in the Service Bay? And notice the fairing right behind the cockpit. In a later version, I might add an Eve Lander onto the front and build a fairing around it. A small cubic octogonal strut right behind the shielded docking port allows for part attachment to a shielded docking port. Normally, they lack attachment nodes. Wanted to save parts and did not include any retractable radiators in a chique service bay at the sides. Unfortunately, existing service bay did not meet my aesthetic requirements for radiator placement. Therefore, Bill and I decided to omit them. What was the worst that could happen anyway? All the heat producing parts have been bolted onto the center back liquid fuel tank (Nerv clusters, ISRU, Drills). As fixed radiators only cool adjacent parts, 3 radiator panels in the aft service bay should keep the craft from overheating and exploding. HyperEdited to Moho, turned on the Nervs. Started time acceleration and went to the get breakfast and shower. Upon return, fuel tanks where empty and the craft still intact. Passed the test. Will this craft suffice, to rescue Anuki Kerman from low Kerbin Orbit? We will see... Mephisto (Every landing, where you can land on your helmet is a good one.)

Hm, bringing a Lab to the Mun or Minmus is an interesting idea for science farming. Might try to steal that mission profile someday...

KerbalX link for the Colibri: https://kerbalx.com/Mephisto/X-108-Colibri-Mini-SSTO Mephisto (Parachutes substitute pilot skill.)

Was experimenting with lightweight SSTO concepts after watching too many videos of Turbo Pumped, Stratzenblitz and the likes. Behold, the mighty (ahem...) X-108 Colibri https://kerbalx.com/Mephisto/X-108-Colibri-Mini-SSTO And in the SPH: Can take off horizontally, landing with parachute assistance. Flight profile is really fun: Take off horizontally, turn slowly to level flight. Accelerate insanely and gain altitude juuust below terminal velocity for rapiers. Orbit was achieved with 400 m/s dV for chemical rockets, 4000 m/s dV with ion engines.

Well, if you put your Eve Lander inside a fairing... Add some wings, wheels and engines to it.... And then strap the whole thing in front of your primary SSTA for world domination. Or leisure cruises. Whatever floats your boat. Then, you'll discover that the Whiplashs lack the oooomph and switch them for Rapiers. Suddenly, it works again. Mephisto. (Almost reliable crafts.)

Mephisto Metalworks and Aeronautics. The Future is now. Link to Kerbalx-Hangars: https://kerbalx.com/Mephisto/craft XR-Series: Go everywhere - Kerbol Exploratory Latest Version is the XR-06 Ranger Mk III SSTA with attached Javelin Eve Landerfor four Kerbals https://kerbalx.com/Mephisto/XR-06-Ranger-Mk-III-Grand-Tour-with-Javelin-Eve-Lander Older Version is the XR-02 Ranger Mk I https://kerbalx.com/Mephisto/XR-02-Ranger-XR-04-Agamemnon-SSTA-and-Eve-Lander Four different crafts in one package: Ranger is a powerful SSTA, Agamemnon is a lightweight Eve lander and ascent vehicle, Tycho is the final stage of the Eve lander and can be docked into Ranger's service bay. Brahe is a moon truck addon for Tycho. Both can fit into Ranger's Service bay. The XR project was built upon results the older X-84 Akkadian / Ishtar project: Fly to every moon and planet in the stock solar system as well as in the outer planets mod and collect science with three Kerbals. The take-off-weight of Ranger SSTA / Agamemnon Eve Lander Combo is 30 t lower than the Akkadian / Ishtar at 120t. XR-01a Tycho Space Sledge https://kerbalx.com/Mephisto/XR-01a-Tycho-Space-Sledge XR-01b Brahe Moon Truck https://kerbalx.com/Mephisto/XR-01b-Brahe-Moon-Truck XR-02 Ranger https://kerbalx.com/Mephisto/XR-02-Long-Range-Scout-Moho--Tylo--Laythe--Kerbin XR-03 Ninsianna Eve Lander and Ascent Vehicle (32t, for Beginners) https://kerbalx.com/Mephisto/XR-03-Ninsianna-Eve-Lander XR-04 Agamemnon Eve Lander and Ascent Vehicle (26t, for advanced Players) https://kerbalx.com/Mephisto/XR-02-Ranger-XR-04-Agamemnon-SSTA-and-Eve-Lander XR-01 a/b Tycho / Brahe combo XR-02 Ranger SSTA XR-03 Ninsianna Eve lander with 32t Ascent Vehicle XR-04 Agamemnon Eve Lander with 26t Ascent Vehicle XR-02 /04 Ranger SSTA with Agamemnon Eve Lander - 120t take off weight. Enough oooomph for every planet and moon. XR-08 Behemoth Multi Mission SSTA 30t to Minmus, 10t to Tylo surface and back (with ISRU...) https://kerbalx.com/Mephisto/XR-08-Behemoth XR-08 Behemoth with Space Station https://kerbalx.com/Mephisto/XR-08-Behemoth-with-Station Dolphin Mk V Mini SSTO https://kerbalx.com/Mephisto/Dolphin-Mk-V XS-Series Extra Small to orbit: Small is the new big, thought the marketing guys. Here's to space on a budget. XS-01 Viper - upload pending- Viper is a lightweight, single use crew transfer system with a rapier and an ion stage. At 30 parts and 5.5t take off weight, it brings one Kerbal into orbit with 7.600 m/s dv left. This should suffice for most destinations in the Kerbol system. Fancy stuff like landing gears or parachutes is omitted. Just power up the engine and fly. TWR in orbit for the ion stage is 0.3, which is fairly reasonable. In order to not only bring pilots into space, it has drone core equipped. XS-02 Sparrow - upload pending - Sparrow is a light weight single stage to orbit concept with one rapier and one ion engine. At 6.3t take off weight, it brings one Kerbal to orbit regardless of profession. As the ion engine only has an TWR of 0.07 in low Kerbin orbit, getting somewhere is a game of patience. XS-03 Sparrowhawk https://kerbalx.com/Mephisto/XS-03-Sparrowhawk-RapierIon-SSTO-to-Minmus An improved version of the Sparrow, the XS-03 Sparrowhawk has significantly greater ranger and twice the thrust in low orbit. Now even with landing gear.The larger battery pack as well as the quad ion engines allow for sustained ion burns of app. 250 m/s. The TWR of 0.12 in LKO is fairly reasonable for ion engines. XS-04 All-Seeing Eye https://kerbalx.com/Mephisto/XS-04-All-Seeing-Eye The latest excrements in ore surveillance technology. Also knows your bad habbits and browser history. Comes equipped with ressource scanners, regular and relay antennas as well as repeateable science experiments. Powered by "a excrementsload of batteries and some spare ion engines", as the designers at the Kerbal Space Center put so eloquently. Comes with solar panels. Has roughly 15.000 m/s dV with ion engines, so evading it by moving to Dres or Eeloo seems kind of futile. Better use that incognito mode in your browser more often.... XS-05 Mighty Flea https://kerbalx.com/Mephisto/XS-05-Mighty-Flea-3t-Micro-SSTO 3t to orbit in a single stage. Kerbal included. No science experiments, no shenanigans. Mephisto. (To infinity and beyond.)

Same issue in 1.4.4. 6x LT2 Landing Struts on a 30t rocket. Command seat inside fairing at the top. As soon as a Kerbonaut enters the command seat, craft wobbles for a small moment and the landing struts explode. Landing struts explode also on Eve touchdown at 4 m/s with parachute landing. 1.4.4. KSP plus DLC Making History Only Mods are Mechjeb and KER.

Ore is 10kg per unit. Basically, you'll need to bring 9t payload into Eve Orbit again. And to bring it somehow to Gilly. Two (theoretical) ways to do this: Go big: Build a reusable SSTO from EVE with mining capability and 9t ore payload capacitiy. When you revover the monstrosity, you are again in budget. Go small: Small is relative, but here we need the usual asparagus staging eve lander, albeit with 9t capacity to orbit. Whole system has to be within 1.159.337 Kerbucks. That sounds rather hard.

X-84 Akkadian at KerbalX The X-84 Akkadian is my attempt at the Ultimate Challenge: Visit every body and moon in the Kerbol system. As a bonus: visit also every planet and Moon in the Outer Planets mod. The vessel consists of three parts: - X-84 Akkadian SSTO - X-84a Ishtar Eve Lander - X84b Traveller Probe core The Akkadian is the workhorse of the mission: It is able to lift itself and the Eve lander into low Kerbin orbit. It has enough delta V to reach Moho from Eve. Enough thrust to land and take off from Tylo or Slate. And, it is sufficiently aerodynamic to land and take off from Tekto. Three Kerbals can travel comfortly and collect science from almost everywhere, except Eve. The Ishtar Eve lander is being lifted to orbit and carried through space by the Akkadian. All is needed are four additional Whiplash Engines and some wings. In order to save some weight, the lander is only equipped with a command chair for one Kerbal as well as some basic science experiments. Also on board is the Traveller probe core. The Traveller probe core is the key to fullfill the Ultimate Challenge: the contract requires a command module or probe core to land on every single planet and moon. As the Akkadian cannot land and take off from eve, and the Ishtar is not built to travel to every other body, the Traveller Probe core is the solution inbetween. It will land on Eve with the Lander. After reaching orbit again, the small probe will dock with the SSTO for the remainder of the voyage. The vessel is surprisingly cheap: the whole package costs under 300.000 Bucks. Take-Off weight from the runway is under 150t. And, practically no clipping was involved. Some specifics for the Akkadian Maximum mass: 109t Max Liquid Fuel: 10180 Max Oxidiser: 4620 Crew capacity: 3 Krew Range and Fuel Profiles: Max Range (10180 LF / 0 Ox): 7023 m/s dV Low Ox (10180 LF / 1000 Ox): 6400 m/s dV Max High Thrust, Chemical Rockets only (3892 LF / 4620 Ox): 2592 m/s dV Use Max Range, if target has low gravity suitable for Nerv only landing (Gilly, Ike, Bop, Pol, etc.) Use Low Ox Range, if target has medium gravity and Nervs require assist from Aerospikes / Rapiers (Moho, Duna, etc.) Use Max High Thrust for landing and take-off from Tylo. Remember to pack additional LF (800-1000 LF) for take-off from Tylo and transfer to Pol. Engines 3x Rapiers (Action Group 1 to toggle, AG 2 to switch mode 2x Nerv (AG3) for interplanetary travel 2x Aerospike to provide additional thrust for high-G landings (Tylo) or more efficient Oxidizer use. Aerospikes have 340 sec vacuum ISP vs. 305 sec from Rapiers in rocket mode. Also, it has 4 detachable Whiplash Engines to lift the Ishtar Eve Lander into Orbit. Ishtar Eve Lander The Ishtar Eve Lander is built to be lifted in front of the Akkadian into Orbit. For this, it has a detachable set of wings and control surfaces. To provide the necessary thrust for ascent, the Akkadian has four detachable Whiplash ram jets. The Ishtar has a first stage with one Vector engine and six asparagus-staging drop tanks, the first two with additional Aerospikes. The second stage is powered by one Terrier and two drop tanks with Sparks. The whole ascent vehicle has enough delta V to reach orbit from sea level with moderate skills. (You’ll have to know the atmospheric properties and general Eve ascent profiles, though. When in doubt, search the KSP forums or watch Eve ascent videos on Youtube.) Maximum mass: 56t with wings, 49t lander only Science Complement: 4x basic experiments (Thermometer, Accelerometer, Barometer, Gravioli Detector) Electricity: 2x solar panels in the Traveler Probe, 2x fuel cells on landing legs.

My attempt at the Ultimate Challenge Contract. - The J-09 Blackstar / Quasar The front part is the Quasar Eve lander, the back part is the blackstar, a Tylo-capable Spaceplane with optional droptanks for extended range for a crew of three as well as a science compartement. The spaceplane part was heavily inspired by Astrobond, the Eve Lander by Bradley Whistance. Although the Whiplash Engines can be decoupled, the whole craft is SSTO capable. Take-Off Weight is under 130t, cost is at 281,812 Kerbal payment units (Do they have a name?) As some clipping is involved, I will not enter it into official challenges (Some fuel tanks are clipped into each other for optical purposes, an Aerospike is behind the middle rapier engine and offset into the engine). Maybe I'll build one without clipping in the future, maybe not. Quasar Eve lander The Quasar is intended to land on the highest mountain of Eve. There, science may be collected and a flag planted. I expect many quickloads, until I'll finish the landing on the mountaintop. Once in the air, wings and gear will be dropped. First stage with Vector, second stage with Aerospike, final stage is a reusable space chair with spark. The space chair will rendezvous and dock with the blackstar. For mission purposes, the space chair's drone core is the entity to land on every planet and moon. The Quasar is built with some nasty offsets to minimize drag and ensure fuel transfers are posible through the heatshield. Also, thanks to severe spaghettification upon disembarking the command chair, a seperate cockpit has been installed in the front. Those fairings turned out to be Kraken-bait. Blackstar SSTO The Blackstar is a Tylo capable spaceplane. With its drop tanks, a trip from Eve to Moho and back should be possible. (We'll see about that. Moho is hard, as many already discovered.) Although the Whiplash Engines and the outermost tanks can be jettisoned, it is technically a SSTO spaceplane from my point of view. With its big mining drill and the small convert-o-tron powered by two fuel cell arrays, it should have enough range and endurance for every other moon and planet. So, Kerbal Space Programm has a fresh installation on my PC, only essential mods like KER and Mechjeb are installed, Ulitmate Challenge contract is accepted. Whish me luck.

I think this is the most inspiring vessel for me I have seen in a long time. All of my SSTU vessels so far have worked with an SSTO Mothership /w ISRU and a seperate Lander for Tylo, which resulted in severla hundred tons of take of weight, depending on vessel. Your vessel completely elimantes the need for a Lander. Was working on a 3 seater version with full science instruments and was still below 65 tons. And even with my meager piloting and navigational skills, I was able to land on Tylo, refuel, take off and land on Pol.

Work in progress: the K-02 Azrael Fine parts to built with in this mod.

Looks like I'm not running the latest version. CKAN offers only OPT Legacy 1.0.9.0. I'll try a fresh install and see whether the issue persists.

Hi there, I had downloaded OPT for KSP 1.3 via CKAN and noticed that with the STAIL Cargo Bay, I had also drag from parts inside. In the hope of replicating the the solution from Jade of Maar, I had a look into the Config. In the OPT_bf_6m_tail.cfg, I did not find a lookup radius. Can someone point me in the general direction how to fix this? Partial Content of OPT_bf_6m_tail.cfg: MODULE { name = ModuleAnimateGeneric animationName = open_bay animSpeed = 1 startEventGUIName = Close endEventGUIName = Open toggleActionName = Toggle Bay Door startDeployed = True availableEVA = True availableFlight = True evaDistance = 5 layer = 1 } MODULE { name = ModuleAnimateGeneric animationName = deploy_ramp animSpeed = 0.2 startEventGUIName = Retract Ramp endEventGUIName = Deploy Ramp toggleActionName = Toggle Ramp startDeployed = True availableEVA = True availableFlight = True evaDistance = 5 layer = 2 } MODULE { name = ModuleLight lightName = Spotlight useAnimationDim = true lightBrightenSpeed = 2.5 lightDimSpeed = 2.5 resourceAmount = 0.08 animationName = LightAnimation useResources = true } //MODULE //{ // name = ModuleLandingLeg // // animationname = deploy_ramp // wheelCollidername = wheelCollider // //suspensionTransformname = LandingSupport // suspensionUpperLimit = 0 // impactTolerance = 150 // //suspensionSpring = 1 // //suspensionDamper = 1 //} MODULE { name = ModuleLiftingSurface deflectionLiftCoeff = 0.3 dragAtMaxAoA = 0.15 dragAtMinAoA = 0.1 } }

Hi, a bit of a late reply, but nevertheless: I like using the combination of an interplantery mothership and a multipurpose lander. Only for the really hard cases I need specialized Landers this way. Eve in Stock or Titanus in the New Horizons mod for example. The Landers should be able to - reach Low Kerbin Orbit from the Space center center with chemical rockets - land and ascent from Tylo - fit in a Mk 3 Cargo Bay - collect science. A multipurpose lander for two Kerbals can be built with around 20t take-off weight These requirements are the basis for the following design principles: 2 Kerbonauts and an advanced drone core, Service bays and Command Seats In order to be able to collect multiple science samples from the same trip, either multiple non-reusable experiments have to be carried or a scientist is on board. A pilot is necessary if no remote control is available. An advanced drone core can be used to store experiments or the Science Container. The drone core can also provide Kerbnet access and supply SAS in case of inexperienced Kerbals. Biggest hindrance is weight. Therefore, seats in servicebays are much lighter than a cockpit and protect in most cases against reentry heat. Good engine performance in vacuum and in atmosphere: Aerospike The engine must provide more than 1 TWR on Kerbin in the atmosphere at sea level. 1.2 to.1.4 is more practical. ISP in vacuum and in atmo must both be rather good. The aerospike is a natural choice, as it has an ISP of 290 in atmo and 340 in vacuum. Drag-optimized design As you are flying through atmosphere, you want to minimize your dV loss due to gravity and drag. This means: no open nodes anywhere, streamlined design, maybe control surfaces. Maneuvering and docking In order to detach from the main craft and redock again, a set of four RCS thrusters is suffcient translation. Rotation can be done with the reaction wheel. Descent modes: Powered descent, unpowered descent, parachute-assisted descent. Because wings do not fit well in cargo bays, they are not used. Descent in atmosphere depends on the density and gravity of the world. The more fuel you can save during descent, the better your range on ascent. If the atmosphere is dense enough, parachutes can slow you down for a unpowered landing. If no atmosphere is present, you'll have to burn your way to the ground with a powered descent. Tylo is the hard case for this in stock. If some atmosphere is present, parachutes can be deployed for slowing down. The final deceleration is with rocket engines. The descent profile is highly dependent on your target body. Generally speaking, if atmosphere is present, you want to make the most use of it with a very shallow approach from low orbit. Stability and center of mass and lift If your lander flips during ascend or descent, a closer look into center of mass and lift is advisable. Does the center of mass change with fuel consumption, so that the center of lift is suddenly above? Do you have control surfaces, to help with stability? Here is an example of a lander concept: https://kerbalx.com/Mephisto/X-82-Selene

So, first post in this forum. Greetings to you! The idea of long range craft with refueling capabilities is very intruiging to me, especially after watching the "Ozymandias" series from Shadowzone. One thing bothered me a little bit in his highly functional and aesthetic craft: The launcher. Sooo big. I was wondering, whether a big launcher could be ommitted if the craft is an SSTO? The Titan III was the first result I published: Lander included with around 6.800 m/s dV. https://kerbalx.com/Mephisto/X-48-Titan-III I tried to optimize the Lander as well, by forcing to use the poor Kerbonauts to work with small service bays instead of a regular cockpit. Turned out really efficient. https://kerbalx.com/Mephisto/X-48a-Artemis-Lander Next one was the same SSTO Concept, but with an Eve Lander. The Hyperion III. https://kerbalx.com/Mephisto/X-51-Hyperion-III---with-Eve-Lander- Streamlined and with more Oooomph, The Kronos: https://kerbalx.com/Mephisto/X-58-Kronos-Long-Range-Expeditionary-Craft Lastly, I discovered Tweakscale and was playing around with it. Finally, I had some really big 3,5m Liquid Fuel Tanks available. And the part count could be reduced by about 100 parts due to upscaling compared with previous models. Last published SSTO is the Endymion, with over 8,000 m/s dV long-range interplantary missions. It was build for the New Horizons Mod, where I wanted tzo pay a visit to the desert planet of Arin with a stop at Laythe beforehand. For this purpose, I needed a craft with rather good atmospheric flight characteristics and the ability to take off in less dense atmosphere of Laythe. Took me a while to figure that out: Endymion Mk IV: - 8000+ m/s dV if filled with Liquid fuel only - reworked Lander with add-on fuel tanks - Relay/ Survey Scan Satellite - slightly over 700t - good flight characteristics - Short take off possible with a kick from the two Vectors