sevenperforce

Even so, our spacecraft look remarkably similar. I admit to seeing your screenshots before I'd finished building my Kerbin ascent stage, so I may have been influenced by your design a bit there. But the return stages (which appear to differ mostly in part placement, and the inclusion of a docking port on yours) seem to be a genuine example of independent convergence. (It does look like my return stage is probably slightly lighter than yours, which suggests that a hybrid craft using your direct flight plan could do better that either of our current entries so far.) I believe the standard mission is cheaper, dV-wise.

Just like Gabaldon's Claire is much better-suited to provide medical assistance thanks to WWII experience than her fully-modern counterparts would.

The series is obviously really adult, but from a technical perspective, Outlander is just about the only realistic treatment of potential time travel...well, anywhere. Claire speaks nearly the same language and is able to come up with believable excuses for the differences. She has enough medical knowledge and experience to be of particular assistance but doesn't need to rely on 20th-century technological advances. She knows an appropriate amount of history for her era and the era she travels to. Reminds me of one of those "Food For Thought" stories I once heard...

A Connecticut Yankee is hilarious, but it's been mocked for 130 years for being a fantastical, aggrandized celebration of "homespun ingenuity" and democratic idealism. There was another novel from the 20th century satirizing A Connecticut Yankee, in which a modern technical expert is punted back to Arthurian times and utterly fails to implement anything more than the barest advances; if anyone remembers what it is, let me know. The technical implausibility of Yankee is pretty well demonstrated by one of the anteclimaxes, which ties to the very first few pages. The protagonist is introduced in the present day (late 19th century) as he remarks on a bullet hole found in 7th-century chainmail armor, and wryly notes that he made it himself. Later, during the high point of the book, the protagonist is challenged to a duel by an offended knight and ends up shooting him with a revolver that he has constructed using a whole advanced military-industrial complex erected behind the backs of the church and the elite. He is then attacked by a whole squadron of knights and shoots 11 more of them before they are finally routed. But constructing a pair of accurate, reliable revolvers in the 7th century is simply beyond the pale of possibility. You need a large-scale steel industry with access to fossil fuels. You need heavy machinery to stamp and forge parts; you need access to purified nitric acid; you need to be able to produce large quantities of constant-purity fulminate mercury. Just getting the necessary infrastructure in place would take a couple of generations.

Keep in mind that sanitation, hydration, and quarantine are concepts that still don't exist in portions of Africa, Indonesia, and South America.

A stone age settlement would be far better off with a couple of combat trauma surgeons and a bunch of nurses than general med students. Medically, the first things to get into operation are: Sanitation Hydration Quarantine That is all. If your community keeps sick people separate from healthy people, if you keep fecal matter away from consumables, and if you have clean water that everyone in the community can access, then your community's life expectancy is easily twice that of the average...up to, like, 1300 CE or so. Everything else (trauma surgeons who can extract foreign objects without severing arteries or perforating organs, nurses who can keep people comfortable and keep wounds dressed and clean) is gravy. Anything that you couldn't implement in a battlefield tent is wishful thinking.

Fixed that for you.

This should be moved to game discussions. But yeah, this is an odd bug. For the record, the satellite doesn't need to point toward Earth with its antennae; all comms in Kerbal are omnidirectional despite appearances. Don't know why it wouldn't charge. Do you have more screenshots?

IS THAT...A FLIGHT ARTICLE?

You can't use the debug menu to rendezvous with a ground target because the debug menu's rendezvous system just places you some distance away along a random vector, which could lead to you being teleported underground or just high up enough to immediately fall and crash. I don't know quite how Hyperedit does it. If you want to cheat yourself to an offworld base then you can do so, but you have to deal with entry and landing. You don't actually have to take along props for deorbit, though. Set the gravity multiplier to 1%, teleport to a circular orbit around the target world, and then warp around until you are approximately right above your target. Then set the gravity multiplier back to 100%. Your earlier velocity will be maintained, so you will simply fall out of space and land where you want to be. Gotta get clever if you are at a higher latitude tho.

Yep!

Time for another "Oh that's simple" challenge. Land a kerbal on the Mun and return him safely to the surface of Kerbin, without using liquid fuel, xenon, or monopropellant. RCS for rendezvous and docking is fine as long as you're not dramatically changing your orbit. No mods. No stock props. Lowest liftoff mass wins. Leaderboard:

It just means that you apply a double layer of glue -- first, a layer on both surfaces to be joined (which you then allow to air-dry), and then a wet layer on one of the surfaces before joining and clamping.

The BE-3 can't match the cycle efficiency of the RL-10 but it has a better thrust-to-weight ratio and it's a lot cheaper.

Anotha day, anotha booster catch. NBD.

When I think about an indefinitely-reusable SSTO spaceship, I think about something like a Firefly-class ship. Dual air-turborocket engines (or RBCC engines) at the center of gravity that rotate, so you can land in a horizontal attitude for safety and loading purposes, with a big ultra-high vacuum engine for transfers. For the present day, trying to do something like Skylon means such a low mass ratios that reusable TSTO is just way better.

Pebble bed can be run much hotter. Melting point of uranium is rather low, all things considered, but you can do a molten pebble encapsulated in a carbide shell. A pebble-bed reactor can also be refueled much more easily than a solid core. A pebble-bed reactor won't have any uranium in the exhaust, but even for a solid-core reactor, uranium that gets into the exhaust is pretty much a non-issue. Specific impulse is a measure of the amount of impulse produced by each unit mass of propellant. Impulse divided by time is thrust, and mass divided by time is mass flow, so this is also a measure of the thrust produced for a given propellant flow rate. Since core erosion isn't counted as part of propellant mass flow, it actually increases isp, technically.

BFS as SSTO does not have enough fuel reserves to re-enter and land, and it does not have enough TWR to lift off at sea level when fully loaded without running the Raptor Vacs, which is not recommended.

Open-cycle gas core is not too far from fragment fission, from a materials science standpoint. It could be done. Damn the fallout. Closed-cycle gas core is unobtainium-powered science fiction. A rotating pebble-bed reactor with either liquid methane or liquid hydrogen (depending on what flight profile you choose) as coolant will be able to nearly match a closed-cycle gas core without all of the nasties.

The problem with nuclear engines is about the same in real life as in KSP -- abysmal atmospheric thrust. They also have the added problem of fluffy deep-cryo propellant and potentially radioactive exhaust. An air-augmented nuclear turborocket (with optional LOX injection for vertical liftoff, or without for horizontal takeoff) can SSTO pretty easily and have good margins for recovery, but you have to play fast and loose with environmental hazards.

Cold launch GG is still pyro.

Have you thought about doing a cold launch pressurized liquid-gas gun? Cold-launched missiles use a powder cartridge to eject them from their silo or launch tube, ensuring they will fall clear if they fail to ignite or otherwise suffer problems. This is in contrast to a hot-launched missile, where the rocket engine is located inside the tube (and you need an exhaust port to allow the rocket exhaust to leave). Here's what one looks like: Why not combine the two? Build your giant space launch gun. Instead of putting in powder, put in feed lines that can pump enormous amounts of liquid nitrogen into the chamber at ridiculous pressures. Instead of using a bullet-shaped projectile, add in a standard conventional solid rocket engine. You would, of course, want to evacuate the barrel of atmospheric gas and use a frangible diaphram on the barrel end. Pump liquid nitrogen into the chamber just before igniting the engine. The expanding exhaust from the rocket engine fills the chamber, beginning to push the payload and attached rocket forward with far greater force than the thrust of the rocket engine alone. As the exhaust mixes with the liquid nitrogen, it flashes the nitrogen from a liquid to a gas, exponentially increasing the amount of gas in the chamber and overcoming (at least initially) the gas-expansion limits on projectile launch. As the rocket continues to fire, the expanding gases continue to propel it forward as with a normal gun, but are constantly being given additional heat and pressure due to containing the exhaust from the rocket engine. Eventually, the rocket's own thrust is producing more of a propulsive effect than the expanding gases, which should be right about the time that the rocket blows through the diaphram and exits into the atmosphere. The rocket engine need only continue firing as a sustainer to push it out of the atmosphere and circularize, and the liquid nitrogen will have protected the interior of the barrel from the immense heat of the rocket exhaust.

The kerolox MVac doesn't have nearly the kind of excellent Isp as, say, a Centaur's RL-10, but the MVac is sitting on a Falcon Family upper stage, which has a mass ratio that makes Centaur look like an Estes. Thus Falcon Heavy's ability to throw 5 New Horizons at Pluto, without needing gravity assists. The trouble is that the only stuff which goes into deep space is science payloads, and those have ridiculously long dev spans.

Yeah, I would use cardboard for a fuselage, for sure. PVC has really good behavior under tensile load so it will retain (and return to) its shape under most circumstances. Although I did have a time that I was trying to do a static fire, and strapped the PVC to the test stand with a little too much tape, and so when the motor fired the heat weakened the PVC, heated the tape, and squeezed the casing shut in the center like a cardboard tube. That was quite a bang. It's possible to build a hybrid rocket using PVC as combined fuel + casing; you just have to abrade the inner surface to expose a lot of surface area and then hook it up.

As we all know, a solid rocket is a pipe bomb that happens to be open at one end. So it may be worthwhile to glance at the BATF's regulations on the importation and manufacture of explosive devices: https://www.atf.gov/explosives/docs/publication-federal-explosives-laws-and-regulations-atf-p-54007/download