mk1980

you should define the "Get to the mun or minmus" part more precisely. there's a big difference between a flyby/orbit and a landing, and there's also a big difference between a one way trip and a roundtrip with enough fuel to get back home.

unless that was changed in the 1.3 patch (didn't play that yet) - this limitation is actually only true for the science jr. material lab and the mystery goo container. the other experiments (thermometer, baromether, seismic thingy etc.) don't require a reset.

do you realize that jet engines have an efficiency curve and simply stop producing thrust at some point when you get too fast? for the rapier engine, that point is somewhere around mach 5.75 i think, and it's technically impossible to accelerate past that point in "airbreathing mode". surviving the heat at that velocity is a non issue, so the challenge boils down to how close you get to the theoretical maximum. i predict that any half serious attempt will end up somewhere in the range of mach 5.6-5.7, so the challenge seems a bit pointless.

oh sure, if you set the funds down to 20%, the situation changes. but i don't think 20% is even officially supported. IIRC 60% is the lowest setting, everything beyond that would require editing the save file or something (?). i've played my last career on hard (60% funds) and SSTOs were definitely not worth using. my rule of thumb was to not spend more than the advance payment of the contract on the rocket. if my design costs more then the advance payment, i know i'm doing something wrong and using an overengineered design. if you follow such a simple rule, the actual completion reward (and usually a part of the advance payment) is your profit. the compeltion reward is usually something like 2-3 times the money you got in advance, so all an SSTO does is increase the margin of profit from 200% to 250% or something, but the additional time you put into the design means the mission takes a lot longer. for simple missions like "put satellite into orbit", a disposable rocket gets the job done in half the time. doesn't matter that an SSTO would save you 5,000 funds or something, that less than 10% of the money you actually make, so you're better off doing 2 satellite missions with rockets rather than 1 mission with an SSTO. i actually wanted to make SSTOs useful in that career. i setup a space station to serve as a refuelling spot and hub for toursit missions, with reusable nuclear spaceships and SSTO planes to get people and fuel up to the hub station. it worked, but it was really just a roleplay thing. later i basically abandoned the station and just shot my tourists to the mun or whatever in simple vertical launching rocket powered shuttles.

if you ignore the price (sandbox), then many parts are useless. why would anyone use a swivel when the aerospike does the same job, but more efficiently? or panther vs. whiplash. the price and required tech are important aspects. sandbox ignores those aspects, so naturally some parts that are cheaper and/or earlier in the techtree are basically obsolete when the pricetag and tech requirements are irrelevant.

jet engines below the panther are basically useless for SSTO planes. you can make a "micro SSTO" with a juno jet engine & spark rocket engine using the 0.625m tanks (or similar) but that thing won't have any payload, so it's just a "toy" for messign around, really. I've had some success with rocket planes using the skipper rocket engine. a skipper rocket can get a few tons of payload to LKO in SSTO style, and you can also turn such a rocket into a rocketplane. the main difference is that the rocketplane will use wings for takeoff and landing, so you can stack some more payload onto it (doesn't need a TWR of >1 to take off as a plane) and you don't have that messy "rocket dangling on parachutes" reentry/landing of SSTO rockets. i suppose you could do similar with swivel engines and 1.25m tanks, but the payload fraction of pure rocket planes is quite low, so you'll probably have to build a bigger plane to get a reasonable load to orbit with a bit of fuel for at least a rendezvous or something. i think that's the most reasonable route for really low tech SSTO planes. you will definitely have to unlock bigger landing gear and at least the first upgrade of the landing strip (and probably also first upgrade of the hangar). overall, it's not worth it in my experience. even a proper jet/rocket hybrid SSTO is barely worth the extra effort you put it for something as trivial as getting a bunch of kerbals from/to LKO. a simple disposable rocket is only marginally more expensive and it gets to orbit quicker, has more deltaV left for maneuvers and you don't have to worry about a pinpoint landing at KSC when all you bring back is a cheap capsule & some crew cabins - doesn't matter if you recover their full value or only half of it when landin on the opposite side of kerbin. SSTO's are mostly a roleplay/vanity thing, tbh. don't use them for efficiency. they aren't efficient when you factor in the extra playtime you invest.

i saw it on steam a few times and made a mental note to check back on it when it comes out of "early access" (i usually avoid early access games even if they look interesting). at some point later, i stumbled over it again when it was on sale (i think it was the steam christmas sale), so i bought it. instantly fell in love with it .

the tutorial is actually over when you dock the two vessels, so there really isn't any need to land the rescue ship on kerbin. if you try to do it anyway and if you have fuel left in the "service module" of the rescue ship, use some of it to lower the orbit first (both PE and AP), but save enough fuel to put the PE into the atmosphere. then do a retro burn that gets your PE somewhere inside the atmosphere. make sure to put the 2 rescued dudes in the command capsule (not the hitchhiker cabin!) and just decouple the lower part of the ship. the capsule alone can easily survive the reentry and will slow down very quickly once it hits the lower layers of the atmopshere. a heatshield isn't required-the capsule is sturdy enough to survive on its own. the PE altitdude is really not that important. i actually like a lower PE better (to speed up the reentry). i've even successfully landed that type of capsule after burning the PE down to -200 km below ground. they get a little hot for a few moments and then slow down extremely fast. a PE somewhere in the atmosphere works just as well. once you hit the atmo, turn retrograde and then you can actually turn off the SAS. the capsule will automatically but the blunt end into the airstream if no outside forces (SAS torque) apply.

just to be clear - i didn't mean that "autopilot" comment as a criticism. I have no problem when people use such mods.

bit hard to tell from the images, but when a seemingly perfect orbit isn't accepted it's usually because your satellite moves in the opposite direction of what is expected.

@Nefrums latest design was a bit... disheartenging to be honest. my ugly "open end" bird was probably the best i could manage, and it's stil about 50% worse then the new design. i suppose i could maybe squeeze out some more efficiency by stealing some of his ideas, but that would be pointless i guess also i'm not going to install mechjeb. i guess it would help (somewhat), but i don't really like the concept of an autopilot. so i guess i'll throw in the towel. maybe i'll make another entry at some point if i come up with some clever idea, but i doubt it will be much better than what i already posted. i guess ~100 funds per ton to a 300km orbit is not too shabby.

a mammoth engine should easily get a 40t payload to orbit SSTO, provided you get it into a somewhat decent gravity turn. the hardest part of the whole trip is probably the landing. it's easy to tip your rocket over and when it tips over, chances are that the upper parts will explode when hitting the ground. the easy workaround /exploit is to hover over the "back to space center" button and as soon as the "recover" button pops up you click it, so the rocket is recovered before it can fall over and destroy itself. design wise, i guess something like a dozen chutes, some airbrakes and a probe core with some batteries are all you really need. maybe an extra reaction wheel to have a bit more control. the trip is simple, really. launch to orbit, depoly the tank in low oribt, wait/fast forward to the point where the deorbit burn gets you somewhere in the general area of KSC (for better recovery value). if you have airbrakes, use them to slow down quicker. make sure you don't overheat and expldoe them, though. wait until you're slow enough to open the chutes... and open the chutes. if you have some fuel remaining, keep it around for the last seconds before touchdown. a little "landing burn" can reduce your touchdown speed quite a lot.

i think the cockpits in general could use better heat resistance (on par with the tanks of the same format, not significantly worse). the nose of the craft takes by far the most heat during reentry, so it's a bit awkward that the "default" nose parts are literally the worst parts for that job. in practice, it's usually not worth the hassle to use a cockpit at all. a probe core can get the job done, and if you want to bring kerbals up, you get better crew capacity per mass by using passenger cabins.

one small addition: if you build craft with very thight specifications, i find the BigS wings/wing strakes quite useful. they have the same weight ratio as the structural wings (0.1 ton weight per m² wing surface) but can also be used as fuel tanks. ie. their fuel capacity is essentially "free" - 4 BigS wing strakes hold the same amount of fuel as 1 mk1 tank, so you save the dry mass of the tank (0.25 tons). not a big deal for craft with simple requirements, but 5km/s in orbit is a tall order, so every little bit can help

ok this is off topic, but in my experience there is always some satellite contract, orbital rescue or station/outpost contract available. some of them may not be doable in 20 minutes from start to cash-in, but they still earn you more "cash per minute playtime" than what you save by using an SSTO to deploy some minor cargo (satellite, probe, station modules etc. - basically anything that isn't "large amount of fuel/ore") of course that also depends on how efficient you are at making rockets. if your rockets are too expensive for what they do, the time saving may not be worth the extra cost. simple satellite contracts in the kerbin SOI are perfectly doable within 10 minutes or so, and even on harder settings they can easily earn you like 50k funds. the advance payment already covers more than the cost of the rocket+satellite and the reward is pure profit.

frankly, if you're looking for easy money, the avionics tech is the wrong branch. you hardly make any money at all with those stupid survey missions. you should get the rocket techs. satellite (and later space station/outpost) contracts are easy money - big reward, very little effort.

is that a new type of contract or did i miss something? afaik there are only 3 types of surveys - on the ground (usually seismic survey once the instrument is unlocked) - in flight *below* certain altitude and in flight *above* some altitude. the latter can be an arbitrary altitude as along as it's above the specified value (ie. passing over the spot with a capsule in orbit also counts). or are you talking about a different type of survey i'm not familiar with?

i always put shielded docking ports on the nose. i suspect a heatshield would have a similar effect, but it's overkill actually. i honestly never managed to blow up a shielded docking port. the other big adavantage of the docking port is of course that the nose is by far the best location for a docking port - with that configuration you can dock a >100 ton plane without even adding rcs thrusters, just some careful trhusting with the main engines to keep prograde & target vector overlapping. i did try various thrust levels to get to orbit and i'm now convinced that minimizing engine count is not worth it. my first entry had only 8 rapiers for ~240 tons. the runway TWR was 0.32. it made its way to orbit, somehow, so it does actually work. the follow up plane had a bit less fuel mass and used 12 rapiers and in the end it was more efficient. the final submission (without cargo bay) also had 12 rapiers and even less fuel (only ~180 tons fully fuelled) with a runway TWR of about 0.7 - and it used by far the least amount of fuel of the 3 designs. so my conclusion is simply that you don't make the plane more efficient by using less engines. it just ends up taking far longer to get it superspnic and climbing. by the time the 8 rapier thing finally got to ~400 m/s, it had already burnt like 4000 units of LF.

the vector engine is also 1.25m, has about 5 times the thrust of an aerospike (at 4 times the weight) and has better Isp at sea level (295 for vector vs. 290 for aerospike). the mammoth has pretty much the same thrust characteristics x4 since it's really just 4 vectors glued together. might be oversized, but it's sort of a "lower part count" option if you want to go really crazy and decide to lift more than just 1-2 tons to orbit.

i guess i would use the remaining fuel to get back to LKO (maybe also try using a mun gravity assist to slow down), refuel the mission in orbit and wait for the correct launch window

in my experience, the whiplash & aerospike combo works very nicely for crew missions to low orbit. i'd even say it's superior to rapiers for that type of mission. the main difference between whiplash and rapier is that the whiplash produces more thrust at low speeds and less thrust at high speeds - and the top speed and altitude is quite a lot worse than that of the rapier. for a quick crew mission to LKO (ie. minimal payload) the higher "early" thrust of the whiplash allows for a more aggressive, steep ascent. this way you get to orbit almost as fast as a rocket. time is an important economic factor - if you spend 20 minutes on a mission using a plane and you could do the same mission with a rocket in 5 minutes, the rocket is probably more efficient overall (since you can earn A LOT more money in the saved time than whatever amount of funds you saved by using an SSTO) - unless you lift a very heavy payload or you send up crew (which you'd have to return to kerbin anyway, so the additonal "must reenter and land" problem of the plane is covered by that). so for small payloads, reduced mission time is more valuable than "absolute" fund efficiency (in my opionion) other than that... well, i guess it's worth pointing out that SSTO planes with panther afterburner engines (+some early rocket engine such as a swivel or terrier) are possible. they aren't particularly good at anything, but you don't need to invest a whole lot of research points to unlock the tech, so they are a more or less viable alternative to rockets in the "mid game" for some mission types. also, as bewing and icedown pointed out - if you plan to do more than just a little rendezvous & docking in LKO, adding a nuke or two into the mix can greatly increase your mobility in space.

i've had some success with using the Large or Extra Large landing gear (with the suspension slider set to something higher than the default "1") as main gear fairlyclose to the CoM and using one (or 2) medium gears on the front. medium gears a lot shorter, so it's a bit of a hassle to place all the gears so the plane is still somewhat level, but the medium gears in the front are steerable, so that's an advantage. i've experienced some very annoying "swerving" on the runway when the main gear is not perfectly parallel. that can easily happen when you attach it to something curved like BigS wings. that's especially true if you angle the wings upwards to generate more lift in level flight. it's often easier to attach it to one of the the mk3 parts of the main fuselage and use offset/rotate to move it a bit outwards. regarding the cargo bays: i think i read somewhere that there may actually be a bug with the aero overlay/gui. ie. the parts in the cargo bay actually don't produce drag, but the aero overlay still shows the alarming super long drag vectors. not sure what's actually going on there. TBH i never found much use for cargo bays in career, so i rarely use them.

i don't think there's an easy way to calculate that at all. far too many factors are in play. assuming you build your SSTO with the top tier RAPIER engines, you can realistically get about 1600 m/s out of them in the super efficient air breathing mode, and they'll get yout to about 22+ km altitude in that mode. from there, you'll need something like ~1000 m/s in closed cycle mode to get to orbit (maybe a bit less if you're really good at that stuff). it's hard to tell how much LF you'll consume during the air breathing phase, since that depends heavily on the drag of your plane and also to some extent on the thrust/weight ratio (you'll spend more if you packed too little thrust, but you'll also spend more fuel in closed cycle mode later if you packed *too many* engines) - so there's always a question of balancing you can probably make an informed decision by draining some of the LF out of your tanks and look at the closed cycle deltaV (ie. a rough simulation how much "rocket" dV you'll have at the end of the airbreathing part). if that number is too low ( < 1000 m/s) chances are that you won't make it up (or - even more embarassing - you won't have enough dV for the reetry burn ) a few things i've learned regarding planes (that may not be immediately obvious) - it's not always helpful to add more fuel to get to orbit. there are cases where additional fuel will not improve the situation but actually make it *worse*. there is such a thing as too much fuel. - there are also situations where too many (or too few) engines will make a design unsuccessful (as mentioned earlier). forget everything about thrust to weight ratio you learned from rockets. planes are different. if your plane has a TWR of > 1 on the runway. you have too many engines. - the ramjet engines (whiplash/rapier) and to a lesser extent also the panther afterburner engine have relatively low thrust on the runway ("static thrust"), but gain a lot of extra thrust once you accelerate a bit. a rapier can go from ~180 kN (?) static thrust all the way up to ~460 kN thrust at mach 3.7. it will start losing thrust beyond that point. - aerodynamcis are extremely important. most of the energy built up to get to orbit comes from the airbreathing phase, and the jet mode only works in atmosphere. so unlike rockets, you can't just get out of the thick atmo ASAP to avoid most of the aero drag. you have to stay in the atmo long enough to build succicient speed to make it to orbit. - wings provide lift, but also create drag. there's a fine balance between enough wings to take off and not fall down immediately and too many wings that will make your plane less efficient when you try to get it to mach 5+ during the ascent

i think the shock cones used to be more light weight and their mass was increased quite a bit with some patch, so it may be a good idea to use something else that not only adds mass but also helps otherwise. like the 1.25m -> 0.625m adapter tanks with a small 0.625m nosecone on top. they look fairly aerodynamic and they hold some fuel.

wow that's really impressive. one question: are 2 shock cones actually enough to run 10 rapiers? i always used something like 1 cone per 2 rapiers, but your craft looks like it only has 2 shock cones (and no precoolers or other intakes)? or are there hidden/clipped intakes somewhere?