GoSlash27

Multiengine spaceplanes The process of building multiengine spaceplanes is the same as single engine spaceplanes. You just double the specs and go flying. Except for one important difference... "Houston, we have a problem..." This is an example of asymmetric thrust due to oxygen starvation. The way the game engine works, one of the engines will starve and throttle back, leaving a surplus of oxygen for the other engine. Before you know it, you're doing the rhumba at mach 6. It's too stupid to realize that the left intakes are meant to feed the left engine and vice-versa, so all the air you grab goes into one big pool and the engines draw from it in the order they were placed. Whichever engine was placed first gets all the air it wants, and the second engine gets the leftovers. Thankfully, there's a fix for this...

Legitimately, I've put an ion glider into orbit with a .324 t/w ratio. My jet/ rocket hybrid spaceplane SSTOs work at a peak t/w of 1.53. Illegitimately, I've put a kraken drive infiniglider into orbit with a 0.00 t/w ratio. Thrust to weight doesn't matter. What matters is lift- to- weight and thrust- to- drag. Best, -Slashy

Yeah, and I'm not pickin' on ya. Just pointing out that the "broadcast already faked footage" part of it wouldn't actually work. Best, -Slashy

Except that wouldn't work. The signals have to *actually* come from the moon, otherwise the Russians would notice that the bearings don't match. Now... you *could* send a small ship to the moon and have it transmit pre-recorded images, audio, and data. Best, -Slashy

Yes. Post a screenshot within the SPH with the center of mass and center of lift highlighted. Turbojets with (in your case) an LV-N. Yes, but a pain in the butt, you can't navigate properly, and it's really not necessary. It's all relative. The way to go about building these is to 1) have everything in the proper proportion to maximize your efficiency and 2) Use the best parts. For each 15 tonnes of aircraft, you want 1 turbojet, .015 m^2 of intake area, and 15 CL worth of wings. It should be stable. Best, -Slashy

A little sleight-of hand would solve that. One guy in a spacesuit looks very much like another, and there's no actual footage of the astronauts ingressing or egressing the capsule. The astronauts never board the capsule, but instead change out of their suits into hardhats/ lab coats and leave with the pad crew. After filming at the sound stage, they are flown by helicopter to the recovery carrier. Then flown out on the recovery chopper, outfitted with their spacesuits, and returned triumphantly. Not sayin', just sayin' Best, -Slashy

Wouldn't matter AFA the fundamental self- contradiction of the conspiracy theory. Without the competition, there's no reason to bother having a (real or fake) moon landing. If the Russians were faking and we knew it, it'd just be a matter of calling them out on it rather than instituting a multi- billion dollar decade long crash program. If the Russians were faking and we didn't know it, then the motivation remains the same for our side; fake the landing to fool either a) the Russians or the American People. Fooling the Russians is pointless if they're collaborating with you and already know it's fake, and the Russians would have no earthly reason to assist our government in convincing it's own citizens that democracy is superior to socialism. Any which way you cut it, the Russian co-conspiracy angle is self- defeating. And since they were monitoring everything, they knew that the transmissions actually did come from the moon. Best, -Slashy

panzer1b, Actually, scratch that. I'll leave this challenge for somebody else to complete. I feel no need to prove my knowledge of KSP aerodynamics to you by improving your craft for you. It's a fine looking craft, but it must be heavily clipped together and could prove more of a headache to play with than I want. You are, of course, free to take or leave my advice as you see fit. If it's working fine as-is, you're probably better off not mucking around with it. *edit* My post upstream was erroneous. You need 2 intakes per engine for a total of 6. That's adequate to keep your engines lit high enough for terminal velocity to exceed your speed limit. Best, -Slashy

Actually, they weren't intending to colonize. The Santa Maria ran aground and was damaged beyond repair. They didn't have enough room on board the other ships, so they left about 40 men behind.

On the subject of Columbus... He didn't set out on a quest of scientific discovery. He went looking for a new trade route to Japan and China and was looking to make himself very rich in the process. And Ferdinand didn't fund his expedition out of scientific curiosity or any altruistic motives. He funded it because he wanted Spain to be the major player in the spice trade, since the overland route was too dangerous. At the end of it all, he conquered the indigenous people in the caribbean and ruled with an iron fist, using torture, mutilation, and slavery. He was so brutal, he was stripped of his governorship, thrown in jail, and never did receive the 10% on profits he had contracted for. Columbus doesn't make a good example of exploration for discovery's sake. Best, -Slashy

Last thread-spamming post from me. I added a couple radial intakes in the back (shoulda had them all along to make .01 m^2/engine). The wings are 2 pair of swept wings with 3 structural Ds to give us a little positive roll stability. With the payload fully fueled, this thing has just enough to make a 72x72 orbit, deorbit, and land. Best, -Slashy

I relocated the landing gear, fixed the intake assignments/ got rid of the unnecessary intakes, fixed the control surface assignments, and replaced the insertion rocket with a couple 48-7S rockets to save weight. Do you want the craft file, or would you rather do it yourself for the experience? Best, -Slashy *edit* Just noticed that you had drained all the fuel out of the payload to save weight, so I put it back. It can still orbit that payload, but not with those puny delta wings. Getting from 25-32KM altitude requires traveling at terminal velocity, keeping your pitch under 22 degrees, and still climbing. I'll beef that up a bit. It'll also be more pleasant around the runway that way...

I pulled off the extra wings, aligned the wings and control surfaces, and had a go. It flies just fine this way. Other observations from my notes: -Your control surfaces should be mapped to do only what you placed them to do. You shouldn't have your elevators, ailerons, and canards trying to control yaw. -Your intakes are not assigned to their individual engines properly, and it suffers asymmetric thrust at high altitudes. Unfortunately, this was just enough of a problem to keep it out of orbit. Here is how you fix that. Just do what I did and fix the intake assignments and you'll have a good starting point. There are a lot of tweaks you could do to this to make it more user- friendly and efficient. It's almost to the point where you could get by on one engine. Best, -Slashy

A few things jump out at me as potential problems beyond what Raptor has pointed out: Having your wings inclined like that is definitely going to reduce your efficiency and increase your drag. You're using delta wings, which have just about the worst lift to drag of any wing surface. For larger wings, I recommend the swept. Also FWIW the orbital insertion rocket on the back doesn't need to be that big. It's not a dealbreaker, but hey... free weight. I'll play around with it for a bit... *edit* yeah, the engines can't make any thrust with those wings behind the exhaust.

KIA stands for "Killed In Action". It says he's dead. Best, -Slashy

Funny you should mention Columbus. I thought you might. Update coming tomorrow... Best, -Slashy

3: How to fly an SSTO Spaceplane: This is an example of a proper launch profile: http://s52.photobucket.com/user/GoSlash27/slideshow/KSP/SP%20profile The first 10 KM of altitude: Climb as fast as you can while maintaining at least 100 m/sec velocity. 10-25 KM: Slowly taper off your climb rate to 100 m/sec so you don't find yourself too high and slow 25-32KM: Build speed and keep your angle of attack at 22 degrees or less. Above 32 KM: Keep the engines lit by throttling back and continue to climb at 100 m/sec. Once you've stopped gaining speed (well over 2300 m/sec), it's time to engage the rockets. Close the intakes (action group 1) Once apoapsis is achieved, engage your orbital systems (action group 2) and treat it like any other rocket. Landing: Do a normal retroburn for KSC, then Open the intakes (AG1) shut down orbital systems (AG2) and disable the rockets (AG3). Rotate to prograde do attack the atmosphere head- on and verify that your action groups performed properly. Once reentry heating subsides, throttle up to 1/3. Now you're just a regular airplane. Fly back to KSC and land. Best, -Slashy

2E: This is only a test... Take it out and fly it to find out where you went wrong. Try it with full tanks, nearly empty tanks, full payload, and empty payload. Make sure it flies well, and takes off/ lands without any embarrassing 'spontaneous disassembly' problems. In the case of this example, I had to reposition the main gear a little closer inboard and further back to keep from accidentally removing the turbojet. 2F: Movin' On Up Take it into a few high- speed runs to make sure it's stable throughout the launch profile and at high speed. There probably won't be any issues, but best to make sure.

2D: The finishing touches Time to fill in the last little bits of detail work. Refill the tanks. Fuel tank gets 180 and the LF+O tank gets 135 fuel and 132 oxidizer. We will add control surfaces, but very little. We're making a spaceplane, not an air superiority fighter. Stability and precision are our friends. So we add a couple Elevons in the back for basic controllability and (and this part is important) a couple canards in front to counter- balance the elevons. Why? High- speed stability. We don't want a longitudinal imbalance in drag by having control surfaces at just one end. Rudders? We don' need no steenkin' rudders! Almost done now. Add gear. Nose gear gets active steering and no brakes. Adding anciliary systems (lights, solar panels, RCS quads), setting up action groups (1= close intakes, 2= activate orbital subsystems 3= disable rockets for flying home) and setting up staging. Ready to go crashin'!

2C: I went to 'Ludicrous Speed' and it went plaid... During the terminal phase of launch and reentry, KSP spaceplanes can often exhibit a tendency to want to fly backwards. This is a result of "drag misalignment". The builder accidentally put high- drag parts in the front and low- drag parts in the back. Much like an arrow fired backwards, it doesn't like to fly that way. High-speed stability: The tendency of a spaceplane to to respond to high- drag situations by pointing it's nose in the direction it's headed. We already solved this in the 3rd post by putting the intakes as far back as we can mount them. Intakes are the highest- drag part of the plane, so keeping them aft is enough to give us good high- speed stability. Another big culprit is having wings too far back and using canards to balance them. Of course, we won't do that...

2B: It practically flies itself... We could pretty much slap some parts on this as- is and go flying, but we'd be fighting with the plane the whole way because the airplane isn't trying to help us. That's where "dynamic stability" comes into play. Dynamic stability: The tendency of an aircraft to seek straight and level flight after being disturbed. The 2 big culprits here are roll and yaw. We want an airplane that has been knocked out-of-level in roll to level it's own wings so we don't have to do it ourselves. Likewise, an airplane that is side-slipping with the nose pointed off to the side of where it is going should naturally want to weathervane back into line. Positive roll stability is achieved by gently sloping the wingtips uphill (called "dihedral") and positive yaw stability is achieved by hanging a big vertical board out back to act as a weathervane (called an "empennage"). A couple options for our plane that would work just fine: A single vertical tail and gently sloped wingtips. Twin vertical tails with gently sloped wingtips. Either of these would work fine, but here's my favorite: Wingtips set way back and sloped up 45 degrees to perform both functions with a little less mass and drag. I'll take door #3, Monty.

Static balance part deux: Electric Boogaloo Since we've come up with a happy arrangement, we'll fix the stuff in place that we won't be adjusting. We've added our rockets and intakes, and flipped our docking port to the bottom (to make room and because docking ports on the bottom are very easy to align) Now for the second half of static balance, center of lift. Here's our 14 "strake" wing sections. Obviously, they're too far back, so we'll adjust them and add a few additional sections to make them look pretty/ aid us in making our balance. That was easy. Now on to the next part: Dynamic balance.

Part 2: Insert tab A into slot B So here we see the core sections of our future spaceplane duct taped together. We have our mission supplies (marked in red) and our payload (marked in green). Problem is, this arrangement wouldn't fly very well because it has unacceptable static balance. Static balance: The property of a spaceplane that puts it's center of gravity in alignment with it's center of lift and keeps it's center of gravity from moving very far as the fuel drains off. An aircraft with poor static balance will be either nose heavy(bad), tail heavy (catastrophic), or will change this tendency as fuel drains (really not good). We need to get this fixed by re-shuffling the sections to put the center of mass in the middle of our fuel tanks. This arrangement seems to work pretty good. We will drain our fuel tanks and re- check it to see how far our center of gravity moves as we burn fuel. Very good. It didn't move much at all. We'll leave the fuel tanks empty for a while to represent a "worst case" while we continue building. Last thing we want is a tail- heavy plane.

This is a quick how-to guide for constructing a safe, reliable, and efficient spaceplane for stock KSP.25. This design relies on proper piloting, so there is very little room for error due to an inefficient launch profile. This little guy has just enough supplies to do the job with 20% reserves and fuel to get you home safe. Not to worry, though; I'll include an example of a proper launch profile for this type. This tutorial will consist of 3 parts: Part list, Assembly, and operation. NOTE: While many of these philosophies and techniques apply to FAR, this SSTO will only work in stock installations. FAR derates turbojet thrust to make this sort of thing impossible using turbojets. Prologue: What spaceplanes are for While SSTO spaceplanes can be used to perform a wide range of tasks, they are rarely best- suited to many of them. This design is optimized to fulfill the role that is best- suited for SSTO spaceplanes: Shuttling Kerbals and supplies safely and cheaply from KSC to LKO and back. While you *can* use SSTO spaceplanes to do other things, that's not what this primer will teach you to build. Nevertheless, the concepts and procedures taught here are universal for spaceplanes, so feel free to apply them to what you are building. Part 1: Mommy, where do spaceplanes come from? From experience, I have distilled the spaceplane down to a simple collection of parts put together in the proper fashion. It's very much like a recipe. Required parts -1 Mk 2 cockpit (drained of monopropellant) -1 Mk 2 docking port (15 units of monopropellant) -1 Mk 2 fuel section, short (180 units of fuel) -1 Mk 2 F+O section, short (135 fuel, 132 oxidizer) -1 Turbojet -2 48-7S rockets -4 XM-G50 radial intakes -14 "strake" wing sections -3 short mark 2 sections of payload of your choice. These can be passenger compartments, LF+O, monopropellant, or payload bay contents. -assorted anciliary bits and pieces (landing gear, control surfaces, lights, solar panels, RCS thrusters) You can mix and match your payload as required to make a hauler that best suits your needs. This tutorial uses 1 load of LF+O, 1 load of monoprop, and 1 load of xenon tanks in a cargo bay. Part 2 will deal with how to use these parts to make a safe and easily flyable spaceplane.

101: When Snooki has a New York Times bestseller.