GoSlash27

nh33nh, The easiest thing for new players to do is failing to go to space. Usually step 1 is to figure out how to get into space. Step 2 is to figure out how to orbit. Step 3 is getting a kerbal to orbit and back to Kerbin without killing him or her. Best, -Slashy

I generally line up one axis at a time for safety. First I set myself up so I'm a few meters clear of the target port's plane. Then I line up lateral, then vertical. Finally, I close to target at not more than .2m/sec, correcting any errors as I go. It gets easier the more you do it. Best, -Slashy

Jeb Kerman's economic stimulus plan: Crash rockets into building. Good for jobs in the aerospace industry and civil engineering. Best, -Slashy /I wonder how long we can keep this thread alive without somebody ruining it by going political

DalisClock, What The_Rocketeer said. If you just want a working spaceplane, a piggyback spaceplane is just about the worst way to do it. It's much easier to make an SSTO spaceplane. The easiest design I've found for a vertical lift spaceplane is to sandwich the spaceplane between 2 boosters like this: The drag of the tailplane and wings tends to stabilize the rocket this way. If you put the spaceplane on top of the stack, then you need more wings in the tail to make it stable. Best, -Slashy

Starhawk, This one's just a testbed at the moment, not a serious design. I'm just trying to see how much payload/ efficiency I can achieve with these concepts right now. Best, -Slashy

DalisClock, Here's a good discussion of the ins 'n' outs of piggyback- style launchers: http://forum.kerbalspaceprogram.com/threads/132178-how-to-make-space-shuttle Fair warning: They're much more difficult to make than SSTO spaceplanes. Best, -Slashy

Playing with the concept, a 60t+ payload tanker Not sure if I'm gonna go this way in the final version... Best, -Slashy

Interesting! After digging and experimenting, I've managed to come up with an intake combo that's less draggy than the shock cone : Tail connector A occluding a precooler with 1 structural scoop attached. This adds a little mass for a complete engine assy (2.4t vs. 2.1t), but it dramatically reduces the supersonic drag. Best, -Slashy

All, Please ignore my previous about the intakes. I just tested it out and it doesn't seem to work that way in practice. At the same mass, the bicoupler intake setup actually has better performance. Upon further testing, the occlusion is more than I had thought and the math works out. 2 shock cones with a bicoupler represents a flat plate of 1.14m^2 a sharp nose with 2 parallel shock cones is 1.70m^2; way worse. a single shock cone with 3 structural intakes (adequate) is 1.16m^2; still not quite as good. For parallel pods, it's better to go with pairs of Mk 1s than the bicoupler. That gets the flat plate area down to .728 vs. 1.14 for the bicoupler. Sorry for the confusion! -Slashy

A few odds 'n' ends that I have figured out this week: *Shrouded solar panel arrays are draggier than they look. It's much cleaner aerodynamically to surface mount single panels instead. In fact, even the Gigantor XL is less draggy than the shrouded arrays when stowed and mounted longitudinally. *RCS blocks are draggy, while the linear ones aren't. Try to use linear ports instead. *Landing gear are cleaner when mounted backwards. *Folding ladders are draggy and they don't get any better by clipping. Try to avoid using them. *The tail cone is draggier than the shock cone intake in the subsonic regime, but much cleaner in supersonic flight. It's worth using on larger spaceplanes where it's mass isn't such a penalty. *Some parts look cleaner than they actually are. For example, I see this a lot: This *looks* like it should be clean, but it's really not. KSP treats the entire face of a part as having the same uniform drag coefficient. The bicoupler has an area of 2.92m^2 and drag coefficient of .843 when arranged this way. The shock cones occlude 2.24m^2 of this, but leave .68m^2 exposed at a drag coefficient that's little better than a flat plate. It'd be better to radial mount mk1 parts and attach the intakes/engines to that, where the intake occludes the entire stack. *On the subject, the structural intakes are much cleaner than initially reported. They are nearly as clean as shock cones. Best, -Slashy

Cairol, It used to be that way, but it's been changed since 1.0 and the wiki hasn't been updated to reflect it yet. KSP models the drag and mass of these parts, but the single panels are treated as "physicsless"; their mass and drag is added to their parent part. Also, their drag cannot be occluded by other parts in front of them or clipping them into their parent. They are exposed to the airflow even when they look like they aren't unless they are inside a fairing or cargo bay. The specific drag numbers for each type of panel mounted for minimal drag: Type/Exposed area/Drag coefficient/slipstream "side drag" single panel/.006/.738/.534 1x6 shrouded/ .107/.869/.177 1x6 simple/ .058/.873/.519 Gigantor / .104/.814/1.24 flat plate area that induces roughly the same drag (subsonic/supersonic) single panel/ 4.6mm/4.4mm 1x6 simple/5.2cm/5.1cm Gigantor/9.1cm/8.5cm 1x6 shrouded/9.4cm/9.3cm ^The gigantor XL actually generates less drag when mounted longitudinally than the shrouded solar panel arrays and you would need to mount 20 surface mount panels to have the same drag as a single shrouded array. Best, -Slashy

^ Yup. Especially with Mk2 fuselages. They try to create lift and when they do it's extremely inefficient for drag. If you can get it set up so that you're aligning the fuselage with the slipstream, you need very little thrust to get it supersonic and beyond. Less thrust means less engines, which means less of everything else that's not payload. This cascades and propels spaceplanes into super- efficient territory. It's all about the mindset of eliminating waste instead of adding stuff. All praise the drag Gods! Best, -Slashy

RexKramer, Bicouplers are actually very good for that job. It's just when people turn them backwards to use them to mount intakes when they turn piggy. If you want to mount intakes and engines parallel to the main fuselage (this is often a necessity), it's better to use Mk1 parts. That way the shock cones occlude the entire stack. Best, -Slashy

The ideal solution is to build designs that don't require multiple fuselage stacks or strutting in the first place. A single fuselage means less frontal area, which means less drag. Less drag means less engines, fuel to feed them, and structure to carry the fuel. Less of all this means less wings, which means less struts (preferably none). Which again means less drag, less engines, and so on. Barring that... If you must use struts, they should be triangulated so that they get their strength from geometry instead of mass. Loads should transform into tension and compression, not shear. The attachments should be aligned with airflow to minimize frontal area. They are draggy no matter which way you point them, but they're less draggy when aligned longitudinally. Best, -Slashy

^ This. If you take nothing else from this thread, take this. Drag is king. If it looks draggy, it *is* draggy and drag is the #1 source of inefficiency in spaceplanes. Best, -Slashy

Cairol, for a Mk2 spaceplane 25% payload fraction is considered good. For a Mk.3 30% or so. I have a Mk.3 that does 41%. I only ever build spaceplanes to go to LKO and back. That is what they're best at. From what I'm seeing from your description, your main problem isn't your ascent profile, but rather your mindset. Spaceplanes aren't perfect when you can't add anything more to them, they're perfect when you can't take any more off of them. Always look for what you can remove, not what you must add. Best, -Slashy - - - Updated - - - By way of demonstration This is an example of what you can orbit with 4 RAPIER engines. Clearly you've got more than you need in that department. This tanker transfers 40t of payload in LKO. Conversely... This plane is in your weight class and orbits nearly 9 tonnes on a single RAPIER. Aerodynamically clean, no wasted mass, and perfectly balanced supplies. This is what makes an efficient SSTO spaceplane. Some specific pointers for your spaceplane: -Mk2 bicouplers are draggy. Try not to use those for mounting paired intakes. -Struts, external RCS quads, and external RCS tanks are draggy. -Too many control surfaces reduce your efficiency and make your handling twitchy. -solar panel arrays are draggy. A couple panels mounted to the tops of the wings are low- profile and clean and will do the job. -Extra engines are mass that you have to carry to orbit. a single RAPIER can do this job. -You can save a lot of drag by setting up the plane with some wing incidence (front of the wings higher than the rear) so that it creates lift while the fuselage is aligned with the airflow. Mk2 fuselages are clean when they aren't crooked. Best, -Slashy

All, I'm not saying that everybody *should* play 100% stock. I'm just saying that there are no mods that every player *should* have. There are lots of mods out there that bring different benefits to the table, but none of them are indispensable IMO. I always play 100% mod- free. Best, -Slashy

^This. The mass offset for engines is fine as it is. Best, -Slashy

Because nobody's said it yet: No mods! 1) keep it 100% stock 2) learn how to all the stuff that you "can't do" 3) ??? 4) Profit! Best, -Slashy

I have some odd kerbal- rating procedures. Some are important, some aren't. Important: The ship must complete an entire mock mission without any mishaps or even potential mishaps before a kerbal is allowed on- board. Except Jeb; he has an annoying habit of stowing away unexpectedly. Unimportant: The ship must be piloted by a kerbal rather than a remote guidance unit and any kerbals must be in a pressurized cabin. My goal is to never have a kerbal die on my watch, so I take the criteria very seriously. Best, -Slashy

By contrast, I have never been through airport security. I flew plenty prior to 9/11, but decided I would not willingly submit to such foolishness, so haven't been on an airliner since. 14 years and still going. But in the interim I did learn how to fly an airplane myself and never had to undergo security screenings to do it (irony) I remember clearly exactly where I was and what I was doing when I learned about the attack that day, but you know what? I also remember the little details of other days in my life when other horrible things happened. The Challenger disaster. The LA earthquake and (years later) Watts riots. The moment the levees broke in New Orleans. The moment the tanks rolled in Iraq. The day that the economy collapsed and Detroit imploded. Many horrible times in my personal life. I remember all these things and carry their lessons, but I don't commemorate them every year. I don't do that because it's not healthy unless there are important lessons to learn from them that I need to reinforce. Bad things happen, and I either deal with that fact or else choose to get stuck in the past feeling sorry for myself. Sorry for rambling, -Slashy

None of the above. E) Smart watches are pretty much a waste of money and time. Seriously... what are you going to use it for that justifies the cost and hassle? What convenience does it offer that you can't replace by pulling your phone out of your pocket? A smart watch is a solution that's in need of a problem. It won't truly be convenient until you can wear it for days on end without recharging it.

Yakuzi, +rep. None of this is at all intended to take anything away from what you've done here. It's good data and you've presented it very well. It's just the nature of the beast that it's impossible to come up with one single set of data (or one test) to define what is best overall from an aerodynamic standpoint. Everything is constantly changing with mach number.... Best, -Slashy

This isn't meant to be political or ruffle any feathers, but it probably will anyway so let me apologize in advance... IMO these yearly reminders of Sept. 11th do more harm than good. It was a traumatic experience and a lot of people died who didn't deserve to, *but*... Saying "never forget" implies that there is an important lesson to remember. Generally if you're on the right, it means that we should always be vigilant and never allow complacency to give the terrorists the opportunity to do this again. If you're on the left, it means that we should be wary of the unintended consequences of meddling in international affairs haphazardly. Perhaps it's both... Whatever the lesson is that we're supposed to be remembering, we're clearly not doing that. We neither act like we are under threat from terrorists nor make any more effort to avoid creating enemies. So then what's the point of all this? If it's solely for the purpose of grieving for the victims and revisiting past traumas, then it's unhealthy. If we as a nation are not going to do anything differently than we did before the attack, then we need to just let it go and move on. There is absolutely nothing to be gained from rewinding the clock back to that day every year and feeling like victims. Again, apologies. I don't mean anything bad by it. Best, -Slashy

I got one of these mainly because I love E6-B flight computers, but I hardly wear it anymore. Smart phones make them pretty much superfluous (although I still wear it on formal occasions) Best, -Slashy