Starman4308

Check these threads. Otherwise, not sure what the issue is: I've never run into something like that myself.

It depends on the landing. 0-1-0 is typically used when there's plenty of margin. 0-1-3-1-0 is used for slimmer margins. 0-1-3-0 has been tested for water landings, but hasn't been demonstrated yet for recovery. As I understand, though, even on 1 engine throttled all the way down, it has too much thrust to hover: they stick it first try, or they don't land at all.

Looks like the primary advantage of going to a 2-engine Ariane 5 is that it doesn't need strapon SRBs to launch, and nobody's seriously tried to reuse SRBs since the Space Shuttle. Regardless, one thing I noticed about this: there is no discussion of all the other factors necessary for reusability: Deep-throttleability of engines. That deep-throttleability isn't enough: the Falcon 9, for example, lands on just one engine heavily throttled down. Falcon 9 can shut off 8/9 engines, this 2-Vulcain Ariane can shut off 1/2 engines, assuming it can gimbal enough to compensate for off-center thrust. Engine restart while flying tail-first through the atmosphere. Recovery equipment such as aerodynamic control surfaces and landing legs. The only "advance" is that the nation that makes the Vulcain engine gets more money at the expense of the nation that makes the SRBs. To get a reusable booster, ESA/Arianespace are probably going to need a clean-sheet design.

Best guess is that white paint absorbs less solar radiation, keeping the LOX just a little bit colder.

Some excellent photography of the Atlas V in that article: a lot of images of transporting and erecting the core stage, the boosters, the Centaur, and finally the payload. Here's to a successful launch of GOES-S.

The only reason mine doesn't look like that is because I delete old crash report folders. Heavily modded KSP installs are not the stablest thing in the world...

Pioneer 1, having completed its primary mission, sacrificed itself for Science in the upper Venusian atmosphere. I then spent most of the rest of my evening putting these three relays into a polar, 35 Mm orbit of the Moon, ensuring near-100% coverage of the lunar surface, and furthermore assuring contact with 4 Mm Communotron 16 antennae even when the Moon is at apogee and just barely outside direct contact range with the DSN antennae on Earth.

I'll point out that landing on the Mun is more than what most people accomplish in KSP. While partly it's because of the stock game's dreadful lack of instrumentation for things like interplanetary launch windows... space is hard. Even with the tremendous simplifications KSP makes, space is really hard. If you're comparing yourself to veteran players who go "oh, I'll just knock together an Eeloo station, no prob"... these people have been playing for easily hundreds, and more likely thousands of hours. Their grasp of orbital mechanics is only instinctual because they've done it again and again and again. And again: I'm pretty sure Squad has said the majority of players never leave the Kerbin system: going interplanetary is the exception, not the rule.

Damnit Bartdon, I'm an engineer, not a rocket surgeon! Also, that fuel transfer is going to make Quissac more aerodynamically stable, for what little it helps... or possibly hurts. Honestly, if the rear tanks were still intact at this point, I'd probably try to shuffle fuel between them to help maintain a very high angle-of-attack and maximize high-atmosphere drag/lift.

It's bone stock RSS with 8k textures. My RP-0 install is unstable enough even without visual mods... and I'm not sure what's recommended for RSS in 1.2.2.

I did less than usual in KSP this weekend, on account of going to a concert. I've completed a high-resolution scan of Venus, and am about halfway through the low-res radar scan. This takes about 120 days, thanks to the very, very, very slow rotation of Venus (period of 240 days). Also, a curious fact about Venus's rotation: it rotates retrograde The last thing I did before leaving for the concert was a suborbital abort test of the Apollo LEO variant. About a minute before sustainer burnout, I deliberately shut down the engines and went for a suborbital Mode 2 abort*. *Current abort modes: mode 1 is to fire the LAS, clear the stack, and align for landing. This goes from T=0 to shortly after booster separation, when the abort tower is jettisoned. Mode 2 uses the service module engine/RCS for separation. Mode 3 would be an abort-to-orbit, and only applies for a short period just before MECO. While successful in recovering the Apollo vehicle, this test revealed very high G-loading (~24G) for Mode 2 aborts, suggesting use of the service module engine not just for separation, but also to soften G-loading on descent. Palmachim completed its last planned mission. While it retains some sounding rockets as a backup option to complete sounding rocket contracts, I've stopped building additional rockets: the return on time spent doing these contracts just wasn't high enough. You may be wondering at this point why a sounding rocket is going so far horizontal. This is because it was a modified sounding rocket, with a 100kg avionics core and RCS added to the first stage, the A4 fins replaced by steerable fins, and the goal: to reach orbit. In the end, it reached a 294x11000 km orbit, running out of batteries a bit east of South America.

Another significant barrier for point-to-point rocket transportation is going to be all-weather capability, serviceability, and reliability. It doesn't matter how quickly the vehicle travels, it's how quickly the cargo itself travels. If it takes a day to load, fuel, roll it out to the pad, and launch, well guess what? The subsonic 747 is already unloading at the destination. While I suspect SpaceX might be able to devise loading procedures quick by rocketry standards, there's other issues: Rockets are more sensitive to weather-induced delays than aircraft. The current standards for payloads sent to space are much more strict than in the air industry: you need to make sure there's no outgassing, that it doesn't have any mechanical issues with rocketry (such as the "your protein cubes have now destroyed the entire rocket" scene from The Martian). Not impossible to solve, but right now rocketry benefits from payloads being produced by people familiar with aerospace, people who know how to avoid outgassing and mechanical issues. In other ways, they're less strict: payloads put an an aircraft probably are never pulling more than 1.5G of acc There are a huge number of airports currently existing: spaceports would have to be built from scratch. Overall, I suspect rocketry has a long way to go before it can compete for point-to-point service with the air industry. It'll be a tough bar to clear, against an industry with proven service on the order of about 24 hours to anywhere in the world. In this arena, a HTHL hypersonic vehicle might make more sense, so long as it can still land on many airfields. The best way I could think of to shoehorn that onto the BFR design would be to replace the upper stage with something with conventional landing gear and aerodynamic surfaces: the first stage would retain VTVL and RTLS, while the upper stage would need HTHL capabilities. For fueling such a design: either you'd be limited to airports equipped with LOX compressors and methane stores, or bang your head against the wall of designing a high-performance engine that runs on the evil rocket-destroying JP-1 jet fuel, plus onboard LOX compressors.

I thought they were still permitted to use cold-gas thrusters? Cost skyrockets as the safety concerns of using a live nuclear reactor require extensive design modifications and elaborate inspections, which describes a lot of the Space Shuttle's cost issues. There's also the issue of "how do you safely land something with a poorly shielded and fragile, lightly-built active nuclear reactor?".

One possibility that springs to mind is launching a Kerbal to space and recovering him safely, using only decouplers and Fleas, as a test of "can you retropropulsively land on Kerbin with SRBs".

One thing I love about the Gimel-2 booster I used to launch Pioneer II to Venus is that the arrangement of the boosters gives a great view of the plume on both the LR-87 hydrolox and E-1 kerolox engines. This time, with no engine failures, the Centaur was just enough for the Venus injection burn, with 70 m/sec left over for a correction burn... though that'll probably be more like 65 m/sec once it finishes sloooooowly turning towards the mostly-normal maneuver node.

Top heavy, bottom draggy. That's it. Ensure the payload is either fairly aerodynamic, or encapsulated in a fairing. Ensure the fairing isn't much wider than the rocket it's launching on. Don't leave small stuff laying around on the surface of your rocket, unprotected by a fairing. If that's not enough, put some fins way down low to help pull center-of-pressure beneath center-of-mass. I feel this trick is a bit cheaty, but you can also set fuel priority to drain from the bottom tanks first. Past that, it would help to have screenshots.

And if they get that many flights in just a few years, I'll eat my hat have the vast majority of my concerns about the BFR allayed. I'm rather confident BFR will fly, I'm just not quite as sure it'll fly often enough and cheaply enough to be the Rocket of the Future (TM). What I will say, though, is that SpaceX has the corporate agility to not stick with a bad idea once they know it's a bad idea. If it doesn't work, SpaceX will move onto their next bright idea for reducing the cost of space access. Unless they start to get seriously beaten at their own game of cheap space access, they're going to stick around for a while.

Unless the control mechanisms are utterly shot, I don't see why the engines can't be shut off, though it may take a few seconds to go from 100% thrust down to zero. I believe one of the early Falcon 1 launches failed because of that: they'd moved to regenerative cooling on the Merlin engine (meaning there's some residual fuel in the engine between the turbopump and the combustion chamber), and they didn't wait for the thrust to die down before separating stage 2. Regardless of what SpaceX wants, I suspect NASA will insist on a LAS. I personally wouldn't trust a no-LAS BFR for crew transport unless they'd demonstrated a couple hundred trouble-free flights in a row, bare minimum.

A few theoretical points to keep in mind: First, in an elliptical orbit, you always return to where you last made a maneuver at. Second, the biggest effects of burning in the six primary directions: Prograde: Increases orbital altitude 180 degrees away from you. Retrograde: Decreases orbital altitude 180 degrees away from you. Normal/anti-normal: Changes your inclination, or how tilted the orbit is with respect to the equator. Radial out: Increases orbital altitude 90 degrees ahead, decreases orbital altitude 90 degrees behind you. Much less efficient than prograde/retrograde burns. Radial in: Decreases orbital altitude 90 degrees ahead, increases orbital altitude 90 degrees behind you. Much less efficient than prograde/retrograde burns. Third: eccentricity is the measure of how egg-shaped vs. circular your orbit is. e=0: Perfectly circular orbit, which is generally treated as a special-case of elliptical orbits. 0<e<1: Elliptical orbit, with higher eccentricity orbits being less circular. e=1: Parabolic orbit. In this orbit, you have exactly enough orbital energy to escape the gravity of what you're orbiting*, and will go off to infinity, approaching infinite distance and 0 velocity. e > 1: Hyperbolic orbit. You have more than enough orbital energy to escape the gravity of what you're orbiting, approaching infinite distance and a finite velocity. *This analysis assumes that whatever you're orbiting is the only celestial body in existence. In the real world, the gravitational influence of other bodies will always make this an approximation. In KSP, because celestial bodies other than the Sun have a finite-size sphere of influence, you can actually escape from an elliptical orbit if apoapsis is higher than the SOI edge.

For a BFR LES, I'd think about just using a Crew Dragon. Put it at the top of the stack. If there's a problem, separate from the rest of the vehicle much like you would for an F9 upper stage failure. If there's not a problem, the astronauts can just egress from the Dragon's hatch into the rest of the pressurized section of the BFR vehicle. It's not like the BFR doesn't have the payload capacity for a Crew Dragon.

Again, screenshots would be very helpful. Also, engine gimbaling in KSP is fairly weak; most engines gimbal less than 5 degrees. If the thrust vector is heavily offset from center-of-mass, you're not going to be able to gimbal enough to compensate for that.

No wonder Mr. Steven missed the fairing. It was terrified of these violent slasher fairings.

They probably just used a crane to put them onboard. Those fairings are probably quite buoyant in calm seas.

Do you have a Unix terminal? If you don't know what I'm talking about, don't worry about it. You could navigate to the relevant directory, and run this command: find . -name '*.cfg' -print0 | while IFS= read -rd '' file; do if egrep -q -e '@.*PART.+MassiveBooster' "$file"; then echo "$file"; fi; done After running that on my own GPP install, the most likely candidate is VenStockRevamp/Squad/Parts/Engines.cfg, which adds a 1.5 degree gimbal range.

I can confirm that the Kickback is not supposed to have gimbal in stock. The part.cfg in my 1.2.2 install has no ModuleGimbal, and there isn't one on the wiki. Granted, the Space Shuttle SRB it's based on had gimbal (even if it frankly would've been simpler and lighter to leave all the gimbaling to the RS-25 liquid engines).