sevenperforce

Challenge accepted.

Transfer only. Think of an Aldrin Cycler or something like the Hermes, where the crew uses a cramped capsule to get down to Mars and back up again, but can enjoy larger accommodations for the lengthy trips back and forth.

It's not about making the challenge easier to complete; most of us can take 16 Kerbals to Eve and back without a problem. It's just a big time commitment. If people can use whatever launcher they want without worrying about cost, or simply start in LKO, it's a shorter time commitment and so you get more submissions. Plus, if you're judging by total mission cost, someone could get a much lower overall cost by building a ginormous launch vehicle using tons and tons of cheap SRBs, while a lighter, more efficient launch vehicle would cost more. That cost difference would vastly overshadow the cost of the actual Eve mission package. Yeah, I wondered that too. I can "mod" a nuclear saltwater engine for $5 that will take a hundred Kerbals from KSC to Eve and back twice on a single stage...if that's just a -300 point penalty I would still come out with 337,800 points.

Tethered hover tests.

I think no, unless it's a considerably large plane. I have my smaller planes take off between 50 m/s to 80 m/s, at tops. Try to lower your takeoff speed. Add action-group-deployable flaps, add canards, make your rear gear closer to the body than the front gear, or some combination of the three. Remember that flaps should be as close as possible to the aircraft CoM for maximum effectiveness. Too far behind, and they tend to force the nose down, which will prevent takeoff. Canards are good for slower takeoffs because they add to overall lift while also pulling the nose up to increase overall AoA.

Can I turn on infinite fuel and use a skycrane to put it up there?

One other suggestion, if I may -- you should allow people to start in orbit (either Kerbin orbit or Eve orbit) to lower the bar for entry.

Haha, that WOULD be lazy. Adding "keep it under $xxxx" is an unnecessary complication because people will make it as cheaply as they can by default. I'd recommend you do two categories: 16 Kerbals to Eve Orbit and Back and 16 Kerbals to Eve's Surface and Back.

Why not just say "16 kerbals to Eve's surface and back to the surface of Kerbin, no ISRU; who can do it for the lowest price"?

That's...sort of...the Higgs field?

You can't do it at L1 or L2, correct, but you can do that at ANY point along the Mun's orbit, including right next to the SOI. As long as you stay just slightly outside the SOI, you can have your cismunar L1/L2 clone by parking right ahead of or behind the Mun in its orbit. If you want to build a cismunar station, then take a Hohmann transfer out of LKO to swingby the Mun at 6,000 m or so at 0 degrees inclination with a periapsis at the point where the Mun's Kerbin orbit path touches the surface, enter the Mun's SOI, then burn retrograde at Munar periapsis until you are just a few m/s short of capture. When you exit the Mun's SOI, you'd be virtually at rest with respect to the Mun and you'll have no trouble maintaining your orbit there. Subsequent missions can follow the exact same approach and they'll always arrive at the same point. If you have a Munar refueling rig, it only needs 807.1 m/s to reach the station.

I just realized you can park a spacecraft at any point along the Mun's orbit and it will stay there relative to the Mun. Including just outside the Mun's SOI. Which means it has the same function as L1 and L2.

I love seeing the lightbulb click on! For a visual: Even with completely-fixed, bilaterally symmetric fins, changing vehicle attitude causes lift due to AoA, which pulls back toward prograde. This, incidentally, is why passively-stabilized, vertically-launched model rockets need to have the fins angled through the center of the stack; it's not enough for them to be merely axisymmetric. I was as surprised as you were!

Gah. What do you think the fins are there for? If there is force due to airflow acting on the fins, then they will be ripped off the capsule if they are only attached at the tip. If there is not enough force acting on the fins to rip them off, they will not provide passive aerodynamic stability. And it actually IS lift. How do you think a fin provides passive guidance? As long as the vehicle remains on prograde, the fin airfoil's angle of attack is zero. When it starts to pitch or yaw off-prograde, the AoA changes, turning the fin at an angle to the airstream and producing lift opposite the misalignment to push it back toward prograde.

I would also point out that placing "floating fins" with the tips attached to the sides of the capsule, intended to break away prior to re-entry, would mean adding four decoupling actuators to the aeroshell of the Dragon 2. The added weight of the structural reinforcements required to keep these fins fixed would decrease payload to orbit. That's also four more chances for a decoupling actuator to fail; if any of them fail, you go nose-first and burn up on re-entry. You would also need to deal with the possibility of the fins colliding with the trunk during an abort. All because...you want a higher TWR for your abort?

Um. As a rule, it is typically considered a good idea to affix all aerodynamic control surfaces firmly to the body of your aircraft. Real life does not have autostrut. Yes, the computer programming running the abort uses differential thrust to throttle the engines on one side just a touch higher than the other side, causing it to turn slightly and fly free of the booster. What you cannot rely on during abort is for gimbal or differential throttling to fight an inherently unstable aerodynamic system.

Even now, the SAS hold function is not absolute; it damps attitude slip and returns generally to the same direction, but things can still gradually go off-kilter. There should be an absolute hold heading that returns you to the same selected heading (like how "target" works) no matter what. And a "hold horizon".

The New Glenn has an octaweb-like enclosure around the base of the engines so they are protected on entry and don't have to do a re-entry burn. The BFR booster doesn't really have faired nozzles at all.

Here, I'll show you. I don't have FAR, but even in stock KSP the aero model is able to accurately model basic CoM/CoP interactions. No LES: LES, engines only: LES, fins on capsule: LES, smaller fins on capsule base: LES, fins on trunk: As you can see, LES is passively stable ONLY when the fins are placed significantly behind the capsule's center of mass. Real-life capsules do not have high-torque reaction wheels like KSP and they cannot rely on computers to use gimbaling or differential throttling in an abort situation.

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Spectacular! I love your use of the Mk2 parts. This definitely counts as reusable and there's no need to go through the individual landings of every other booster.

Those SuperDracos are more powerful than the Kestrel engine on the second stage of Falcon 1. They have no trouble with aborts. There may be a mechanism or design to jettison cargo on abort, but I doubt it. You mean that this: will be unstable after adding a heat shield? Note that I said on the capsule. What you've got are fins floating underneath the capsule, held in place by KSP magic juice. But, by all means, feel free to test it out for yourself. Slap a bunch of separatrons on a Mk1 capsule, add fins, turn off the reaction wheels, and watch it tumble.

This...is...amazing. http://www.lpi.usra.edu/TheSaturnSystemEbook/TitanLandscape/

The fins are to provide passive aerodynamic stability during launch abort. For passive aerostabilization, you want the center of pressure as far back from the center of mass as you can. Like all capsules, the Dragon V2 has its center of mass very close to the heat shield to ensure that the heat shield faces into the plasma during re-entry. It would not be possible to place fins on the capsule substantially behind the center of mass. The trunk effectively holds the fins out at a distance, ensuring that the center of pressure is far back enough for passive stabilization. Fins do nothing to stabilize the vehicle during launch; they actually make the stack slightly less stable. They are only useful for abort.

Bullets expand under heat and pressure to seal the barrel, meaning that the geometry at the back of the bullet will not really affect the way the propellant gases push it down the barrel. Other than the previously-noted problem with a lack of precession damping in a Sears-Haack body, another problem with a conical tail is that it cuts into the amount of available space for propellant inside the cartridge. Some of the old Mauser rifle rounds were very long and very close to Sears-Haack, but even they invariably had a truncated tail.