tewpie

Drake Mk2 (.craft) Payload Fraction: 165.80 / 286.43 = 57.88% External payload design. I spent quite some time trying to get a balanced CoM for both takeoff and landing, and then finally realized it's actually more efficient to just use parachutes and have a perfect CoM balance for take off.

There's a bug in KER where the actual fairing walls are not counted towards mass. So your payload fraction is less than 56.44 because you're using the runway KER mass as total mass which is also lower than what it should be. The mass in SPH should be accurate.

Scarab Mk6c (.craft) Payload Fraction: 153/271.03 = 56.45% Pretty much the same as before, without any engine clipping, size 2 tri-adapters for even lower drag, and tweaked flight profile. Will probably have to switch to external payloads for the next one.

Awesome job @Nefrums, that's a creative entry . Now that I'm kind of off my Fallout binge I'm back to playing KSP. Just dug up an optimized revision of my previous design that I never published, so stay tuned .

[quote name='Slugy']The clipping of most of the Rapiers into LF tanks seemed dodgy (it is very back heavy even with all the forward clipping) - time for a rule update?[/QUOTE] There's other ways to maintain CoM balance without that sort of clipping, but they will make the plane uglier. I'm fine either way. Edit: Just tried it, removing all clipping results in better handling and performance during takeoff (resulting in a slightly better payload fraction). The tradeoff is the plane is significantly more unstable during the landing phase, making autopilot landings a must, whereas currently, you can land it completely by hand. If I'm not mistaken this is the exact same problem experienced by HOTOL (Skylon's predecessor) in the 1980s, due to the rear engine layout.

[quote name='Slugy']The automated flight is very cool too, but it would be nice if it was flyable by human hands.[/QUOTE] If by "human hands" you mean hands assisted with SAS and "hands on" autopilot ala smart a.s.s., then it is very possible to fly this plane, even achieve orbit with the same payload fraction if you time everything right. If you mean naked controls, then no, probably not, but then neither are a lot of other entries and also real world spacecraft ;)

[quote name='Johould']Is an "SSTO" allowed to use launch clamps? This came up while trying to stabilize Mikki's Monster - If it's only needed to survive the initial physics jerk, a clamp is cleaner than more landing gear.[/QUOTE] I think so, the only requirement is that all parts be recovered, and clamps are automatically recovered.

Turns out automated landings are a LOT harder to program for than automated takeoffs. I present Scarab mk6 (.craft): Takeoff Mass: 274.17t Payload Mass: 153.00t Payload Fraction: 55.80% Some highlights: - Single LV-N and 11x RAPIERs. - Uses only 2 shock cone intakes, they are a bit OP. - Uses the new mk3 engine mounting plate and tri-adapters for significant drag reduction (see the triforce in the back?). - (Unclipped) Rapierspikes for further drag reduction. Restricted gimbals to avoid damage. - Minor clipping and offsetting for wet/dry CoM balance. - Uses shielded docking port and cargo bay doors as pseudo airbrakes during landing. - Flight is almost completely automated via kOS. Only manual portion is jettisoning the cargo (and only because I needed time to take screenshots).

Heating is not applied evenly throughout the craft, the forward most component bears the brunt of it. Using a heatshield as the nose will help a great deal. You can also increase drag on your craft and add engines to compensate, but that costs weight (if you use wings to add drag, that offsets the weight penalty a little).

[quote name='Tourist']I've had no problem with any of my existing spaceplanes, either going up, or coming back. My ascent profile has changed bit, in that going for 1600 m/s before switching to rocket engines now appears suicidal. But I've had no problem getting to orbit, with enough juice to complete the mission by going to rockets at 1400 and pitching up a bit. [/QUOTE] You can still go that fast (and even faster) on air breathing rapiers. I hear heatshields are now more aerodynamic than before *hint hint* :wink:

[quote name='Nefrums']I tried to make a new entry in 1.0.5 and I can tell you that Mk1 cockpit is out. It now overheats at ~1.3km/s at 20km... ;.;[/QUOTE] I found that since 1.0.5 cockpits are especially sensitive to high aoa drag heating. For example at mach 5 25km the mk3 cockpit will explode when aoa is above 3 degrees. You have to change pitch very gradually to avoid this.

[quote name='Val']New entry without Rapier-spikes and including recovery...[/QUOTE] Nice, I knew it wasn't a big deal :) Sneak peek at my entry: [IMG]http://i.imgur.com/mY4II1u.png?1[/IMG] Takes full advantage of the enormous increase in shock cone intake effectiveness, and the new engine mounting plate. Overall fraction should be higher than what's possible in 1.0.4, at least for single stage :wink:. It has rapierspikes mounted currently but I'll remove them if rules get changed. I would say keep rapierspikes but don't allow the nosecones to be offset. The simple rule would be, no offsetting of components directly mounted aft of an engine, period. Not allowing offsets to avoid exhaust, except in the case of rapierspikes, is just a weird special exception.

Prepping my entry.. recovery takes a LONG time ;P

[quote name='Val']I've added my recovery to the imgur album in my entry post. A video (~10 min) of the recovery is uploading and will be ready in an hour. [HR][/HR]KSP aerodynamics treats it the same, whether you offset the engines on top of each other or offset the rear engine to the side. No it does not. [TABLE="width: 640"] [TR] [TD][URL]http://www.youtube.com/watch?v=S-t3k1dFo3w[/URL][/TD] [/TR] [TR] [TD][URL]http://i.imgur.com/T9KJJCQ.png[/URL][/TD] [/TR] [/TABLE] [/QUOTE] They do explode if you use gimballing on your engines, which you do on the mk8 but probably not in your test video (I can't tell). They don't explode on your mk8 because you clipped the nosecones into the gimballed engines. In any case, I don't care one way or the other, as long as it's made clear rapierspikes with [B]CLIPPED [/B]nosecones are fine (or not).

[quote name='Right']I don't believe he did. He attached the "Small Nose Cone" on the back, no clipping or rotating.[/QUOTE] Pretty sure a non-clipped small nose cone in the back will explode from exhaust. [COLOR="silver"][SIZE=1]- - - Updated - - -[/SIZE][/COLOR] [quote name='Red Iron Crown']Would it be clearer if I phrased the rule as "No use of the offset tool to create new stacks of axially attached parts"?[/QUOTE] Are you saying anything laterally offset attached axially is a new stack? What about offsetting engines for CoM thrust balance? This is overly broad I think.

[quote name='Red Iron Crown']Have you tried this in 1.0.5? I think the exhaust would destroy the tanks.[/QUOTE] The fuel tanks would be offset to the side. [quote name='Red Iron Crown']Not sure what you mean by this, can you show me an example?[/QUOTE] Like this: [IMG]http://i.imgur.com/UwrBLvO.jpg[/IMG]

[quote name='Red Iron Crown']What advantage is to be gained from attaching a fuel tank to the back?[/QUOTE] It's more stable to have an engine pulling a stack instead of pushing it. You can also jettison fuel tanks easier in multistage designs this way. Also the backs of engines can be used as free attachment points for axial air intakes (rotated 180 degrees and offset forward). Also you can attach an engine + air intake without any fuel tanks with a radial mount point (which can be shielded from drag by offsetting it into a cargo bay).

[quote name='Red Iron Crown']It's part of the same stack. It's the additional engine exhaust area without additional frontal area that I am trying to keep in check.[/QUOTE] Ok, so I can attach anything to the backs of engines (say a toroidal fuel tank), as long as it's not another engine, right?

[quote name='Red Iron Crown']I believe this practice is a bit too exploitative of the aero model and over-penalizes engines with no bottom nodes, so I'm going to update the rules with a "Additional stacks must be attached radially" kind of rule. Apologies to anyone working on designs using this technique.[/QUOTE] Ok, but clipping reversed nose cones into the backs of engines is ok? Cause that's what Val did in his entry :)

[quote name='Right']Tewpie, is engine stacking the same as clipping two engines on top of eachother?[/QUOTE] Not the same. This is mounting an engine on the exhaust end of another engine and then offsetting it to the side to avoid the exhaust.

Nice job Val, that's incredibly close to the 1.0.4 fraction. Now I have to get cracking ;) Red Iron Crown: is engine stacking allowed or not? I have a feeling this actually matters now.

[quote name='Friethjoph']hmmm... What if... We take a Mk2 cockpit, Mk2 comouter core, then an empty Mk2 cargo bay, prop on wheels and fill the cargo bay with seperatrons?That would reduce drag (for they are not in the airtream) but add weight... with enough seperatrons it might work out though, and if the rear wheels are a bit higher than the front onse, it could stabilize the machine to stay on the track via downward lift.[/QUOTE] That was actually exactly what I did for my original all-sepratron design (well, I used a mk2->mk1 long adapter and a tailcone), but I found using a mk1 fuselage (which is now hollow in 1.0.5) has the same effect as using a mk2 cargobay. I think the fastest I got with a mk2 design as around 1150m/s. In any case the limiting factor is the physics engine which seems to generate huge resonant vibrations once the number of sepratons becomes large (>200).

Pure sepratron design 1208.6 m/s, Mach 3.3 [imgur]a1cR9[/imgur] 850% of terminal velocity :sticktongue:

Same as my original design, with a twist and better screenshots ;) [imgur]5jnC7[/imgur] [s]916.4[/s] 939.0 m/s

[quote name='ElMenduko'] To be honest, the only way I could think of that someone could break my record is by using exactly 1 less unit of fuel, which is really hard to do. If you put 0.1 less fuel than needed, I think drag would slow you down greatly.[/QUOTE] Challenge Accepted :sticktongue: