Nibb31

Science fiction is fantasy. It just replaces magic with technobabble. So those thrusters and antigravity devices just use magic with a different name. People who look for a rational explanation for everything they see in Star Trek or Star Wars are just ruining their own fun. It's not about being scientifically accurate. It's about telling a story. Sit back, relax, and suspend your disbelief.

The trunk has fins which are specifically to maintain stability during an abort. The Dragon v2 would separate from the F9 with the trunk attached, and dump the trunk before splashing down downrange.

I don't understand your comment. Dragon never was intended as a lunar lander. There have been proposals to use it as a Mars lander, but those predate the V2 vehicle so they are based on conjecture about Dragon's performance. For Mars, most of the deceleration would be done by aerobraking and you would still need the parachute. Besides, you could land just about anything on the Moon if you use a crasher stage. Soyuz has a dV around 400m/s. I seem to remember reading that Dragon would have 600m/s, but judging by the size of both vehicles, that sounds optimistic without additional tanks.

That's wrong. Proof is that we have gotten way more science out of robotic exploration of Mars than boots on the ground that might never happen. Years of robotic exploration covers a much wider area and provides and longer duration than any manned mission could provide. Robotic exploration is still "manned". It's telepresence. We don't send people to fix deep sea cables or to inspect nuclear reactor pressure vessels because it would be stupid. Instead we send robots and we use remote manipulators as extensions of our bodies. Those extensions are tools, just like computers, cars, and screwdrivers. And after all, what is more human than the ability to wield tools? I said "as a group". Individually, there a some amazing human beings. However, as a species, on the scale of the universe, we aren't any more valuable than a virus.

Not really. I've seen figures of a few hundred m/s. We don't even know if the Dragon V2 has its own tanks to expand the dV on orbit.

That's a completely debatable opinion, not fact. There is certainly nothing factual about manned missions being more cost effective. Quite the opposite. I tend to find abundant evidence that we are pretty apathetic and stupid as a group.

Yes, but if one SD fails before the chute deployment minimum altitude, they will deploy the chute at any rate, just in case another failure occurs. In that case you would have a power-assisted parachute landing with as many SDs are available. You would also probably have balance problems if those 2 failing thrusters are in the same pod. There will be a whole slew of failure modes depending on where and when in the descent profile the failure occurs, the type of failure, and the minimum parachute deployment height. The only "black zone" I can think of is if suddenly 2 SDs in the same pod (or man than 2 SDs) fail below the safe parachute deployment altitude. This is very unlikely. SDs are hypergolic thrusters with very few moving parts (only a couple of valves). They are designed to be robust enough for launch abort scenarios. While a valve can get stuck (and has on a previous CRS mission), it usually happens when the thruster is first used. In the Dragon v2, they will fire for deorbit, and several times during descent, so there will be ample time to discover a faulty thruster before reaching the minimum parachute deployment point. The chance of 2 or more SDs failing late in the mission is very unlikely. In the aforementioned "bad luck" scenario of a double failure on the same thruster pod, they would probably deploy the chute anyway, cut off the opposite thrusters to maintain attitude, fire the others as hard as they can, and hope for the best.

Even titanium would have trouble at these pressures. There is no room on the inside, because there is a mushy human on the inside. Non-existent new technology does not exist. Even if you could devise a spacesuit, you couldn't move with all the weight and pressure. You would need a superthick pressure vessel and an exoskeleton. However, at this point, there really is no point in going outside to walk on the surface for 12 mins if you're going to be stuck inside a 2cm think pressurized shell and interacting through video cameras. You would be better off staying inside your lander and using a telepresence robot for EVAs. Your capabilities would be exactly the same. However, at this point, why land your mushy human body on the surface? You might as well just land your telepresence robot and stay in orbit above the clouds. However, at this point, why bother going to Venus orbit at all when you can control your telepresence robot (with a short delay) from the comfort of a mission control center, and go home to your wife and kids every night. Manned Venus mission is useless.

A civilization would leave some traces. Or else it wouldn't be a civilization.

I dont think even Branson has enough money to develop an SSTO spaceplane, even if it was possible. Spaceplanes are àtechnological dead-end at this point.

There is no 'if'. It simply isn't possible to scale up a SS2-type vehicle to a orbital spacecraft. You would need to add RCS, a TPS, and a much bigger two-stage rocket behind it. It would have to be a massively bigger vehicle with a carrier plane bigger than what Stratolaunch is proposing. Suborbital joyrides might be pointless, but they are the only way to make a profit right now. I don't see any other form of space tourism being profitable any time soon.

An abort would be over the ocean, so it wouldn't need the SDs to cushion the landing if it's a splashdown. For a nominal landing, the parachute deploys only in if one of the SDs doesn't fire. In that case, the other SDs will fire to cushion the landing. The Dragonfly test campaign that is starting next month is going to test all sorts of combinations of abort scenarios with and without parachutes, with various SD failure modes, and with and without the trunk for LES simulations.

A civilization as advanced as ours would have left some traces behind.

The White Knight/Space Ship concept is not scalable to an orbital vehicle. If they want to offer orbital flights one day, they will have to migrate to a completely different type of vehicle or sell tickets on DreamChaser, Dragon or CST-100.

The abort sequence is: - separate trunk from upper stage - fire Super Dracos - separate trunk from Dragon - deploy parachutes - splashdown If the SDs are used for launch abort, then they won't have enough dV for a propulsive landing.

If something goes wrong, they deorbit and land wherever is practical.

How do you know this? There have been zero studies on the effects of partial gravity, either long term or short term. We know that it's possible to live and in microgravity for long periods. We know that exercise and medication can prolong those periods even more. The minimum amount of gravity required for indefinite stays is unknown. For all we know, maybe the human body really only needs 0.1 g to perform normally. Maybe it needs 1g. Maybe it can do with something in between. We simply don't know.

It's not a requirement for CCDev, so probably not. It would launch, rendezvous, and dock in less than a day.

Not really. You get a couple of multi-purpose alphanumeric keypads. The rest is on-screen buttons. The F-35 is not a smartphone. It has flight profiles that are much more complex and diverse than a LEO taxi, yet it uses MFDs for just about everything: And yes, F-35 pilots also wear gloves and might find themselves tumbling and jerking too. The whole point of having fly-by-wire and software controlling every phase of the flight is that you never get into a situation where you are jerking or tumbling. Just like in a modern airliner, the computer maintains attitude automatically and the pilot only has to concentrate on the navigation. You won't need to deal with circuit breakers and maintaining attitude manually because the computer will do all of the micromanagement. Have you tried flying in KSP with MechJeb? You can do pretty much everything with a few mouse clicks, even when things go wrong. Each phase will be automated, and flying the spacecraft will most of the time just involve switching the various modes like you switch panels in MechJeb. Modern spacecraft like the ATV or cargo Dragon pretty much fly themselves, and even dock themselves, to the station with no manual input. Its robust technology.

The worst case scenario is that both screens break. Then, ground ops would take over. You wouldn't fly this like you would fly Gemini or Soyuz. There isn't one button for "jettison cabin door" that needs a keyguard. Commands would come on screen contextually, when necessary, depending on the flight mode and phase. Touchscreens can be used in a professional environment. Look at a modern airliner cockpit. 787 Dreamliner: Airbus A350: Do you see any keyguards? There are touchscreens and most buttons are multi-functional and depend on the mode that the autopilot is in. Any critical commands require confirmation, so there is no need for keyguards. He said it was "flight design" hardware. He didn't say it was the actual operational vehicle that would carry astronauts to orbit. There are some closeup pictures floating around that suggest that the heatshield and RCS thrusters aren't the real thing. My hunch is that it's a test flight article for the Dragonfly tests. It will be used to for drop tests, propulsive landing, and abort tests, but this exact Dragon isn't going to space. The operational vehicle will have lockers and padding inside.

No way. A few thousand feet won't make a difference in the dV needed to reach orbit.

What sort of plane? You can't even fill up a commercial airliner for $1000.

I'm guessing that the touchscreen is resistive instead of capacitive, like the ones that are certified for aircraft operations, so that they can be manipulated with gloves and are harder to press. I'm also guessing that the buttons on the side are for redundancy, in case the touch digitizer fails. As for keyguards, they aren't necessary when you can have a "Are you sure OK/Cancel" dialog box on screen. However, there really shouldn't be much need for a pilot at all. Most of the spacecraft's functions will be automated since they will be shared with the cargo version. The interior is a mock up anyway. As I said above, the flight version will have lockers and padding, and I doubt that the real thing will have leather seats. What else doesn't convince you?

It should be. But automatic docking is hardly a "giant leap". NASA never did it before because it wasn't really needed, but the software to do it is quite trivial.

I think if this is flight hardware, then it's for the Dragonfly atmospheric test campaign, i.e. testing aborts and propulsive landing. It doesn't look spaceworthy to me, especially the closeup pictures of the heatshield and the RCS Draco thruster ports.