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Virgin Galactic spaceshiptwo crashes.......

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Retroflyer_S

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They left Africa in search of food. I don't think there is any food on the moon. And the cost to grow food there is extreme.
Do you want my money for this?
There is plenty of moonlike desert on Earth that would grow food with less effort than the moon, Mars or any asteroid.
In the case of a disastrous asteroid impact, an underground society could survive. Or some scheme to deflect it.
But populating Mars seems ludicrous, in my opinion.
They actually tried that in the sixties inside the "spaceship earth" and the hippi movement, included also hallusinogens and free sex etc.
 

BBerson

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They actually tried that in the sixties inside the "spaceship earth" and the hippi movement, included also hallusinogens and free sex etc.
I didn't find any experiment "spaceship earth".
I do recall the "Biosphere II" in Arizona, that failed in a few years.
 

bmcj

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I didn't find any experiment "spaceship earth".
I do recall the "Biosphere II" in Arizona, that failed in a few years.
I think that's probably what he was thinking about. I believe "spaceship earth" (or something similar to that) was a short-lived TV show.

By the way, I think there are some Mars advocacy groups that have or are planning long term earthbound habitation experiments in remote areas (desert/arctic).
 
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DangerZone

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Manned space gets you these things:

- Faster science return.
- More flexible science return.
- Larger/more reliable space boosters that also facilitate bigger/better unmanned missions.

And, ultimately, there are two reasons that manned space has to happen, regardless of the logic of unmanned space:

1) We need to go. The human race could've sat tight in Africa. Or Europe. Or Asia. No, we went out and explored. With our own two eyes, own two hands, our own two feet. Unmanned probes have returned an incredible trove of information, and I would never cut that program back. But it's not the same as being there. That's a philosophical thing, and sure, it costs a lot of money and you can't measure it with ROI. But I think it's the most important aspect of the space program, top to bottom. The easier access to space becomes, the more this will become important, not less. Right now, we're in the stage of exploration exemplified by the first little boats that paddled or sailed to the British Isles. We're not even at the level of the first Viking voyages to Nova Scotia, let alone the later European explorers. Space exploration is just beginning.

2) Somewhere, "out there", is a comet or asteroid with our name on it. Yes, there is. Sooner or later, there will be a great big bulls-eye painted on the Earth, and despite NASA's nice little press releases, we aren't even near the technology needed to divert one. Sure, we need to invest in developing that technology. But the easiest and best way to make sure the human race continues is to have a "backup" - make us a two-world race and civilization. Our global economy and infrastructure is so fragile that it wouldn't even take a Chicxulub-scale event to wipe us out.

I don't discount unmanned space, and we need to keep that program vibrant and strong to act as the scouts for later manned missions that they properly should be. It's not a zero-sum game. We need both.
Excellent point number 2. In fact, there are two bullets set for 2029 and 2036. The probablitiy of hits are still undetermined because we can't anticpate their exact trajectory even though a direct hit is unlikely. However, their close passage may have impact on global climate change and influence volcanic action.

In terms of stimulation, this is even a better reason to make a space race with bigger efforts than during the Cold War. I've met a woman in Japan who survived a direct atomic bomb hit on Nagasaki as a kid. Her life was saved by a soldier who sunk her into a water ditch, so a nuclear war is survivable. A direct hit of a 400m meteorite might be too, but the consequences of volcanic activity and climate change might lead to wars with people feeding on people. Thus it is always good to prepare for the worst and enjoy life if we dodge a bullet, chilling with a cocktail in hand on some sunny beach instead of an ash wasteland.

It's funny how we were taught as kids that Space is an empty space. Today we understand it is filled with flying bullets in the forms of asteroid and we don't wonder any more why is the Moon full of craters. And Earth too, it's just that most of the really big ones are covered by oceans so we ignore the fact that many times in hostory there were mass extinctions out of the blue. Like that meteorite hitting Russia last year, did anyone see that one coming?
 

Apollo

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From the EAA website:

"The NTSB’s initial findings suggest that the craft’s feathering lock-unlock lever used to stabilize and slow the spacecraft when it returns to earth appears to have been moved from the locked position to the unlocked position prematurely. Officials suggest that subsequent aerodynamic forces then deployed the feathering mechanism, which resulted in the in-flight separation of the wings and vehicle.

SpaceShipTwo tore apart about 11 seconds after detaching from beneath WhiteKnightTwo and firing its rocket engine. At first some observers speculated an explosion occurred, but the NTSB said the fuel and oxidizer tanks and rocket engine showed no sign of being burned or breached."

So the mere act of "unlocking" the feather mechanism was enough. The copilot didn't actually deploy the feather mechanism, he just unlocked it. It sounds like aerodynamic forces then overcame the actuator's holding force, because the aircraft's speed and/or altitude were out of the normal operating envelope for feathering (which is why the mechanism should not have been unlocked).

It's unfortunate that aircraft operating manuals are sometimes written in blood. Part of a test pilot's responsibility is to verify the aircraft's operating limits, and this has to include the potential for human error during such operations. Although the copilot perished, this accident will cause additional safeguards to be built into the feathering system, thereby ensuring this type of accident never happens to a flight filled with passengers. Godspeed, Mike Alsbury.

Disclaimer: The NTSB has not determined the final cause of the SS2 accident. These are preliminary findings only.
 

BBerson

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Can aero forces do that? Seems like hydraulic force would be needed.

Why does feathering work at Mach 1.4, yet not at 1.1 ?
Could have been something totally unrelated to his unlocking the lever.
 

Apollo

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According to the Washington Post, Scaled employees speaking under the condition of anonymity called Siebold’s survival miraculous:

“Siebold found himself flying through the air while still attached to his ejection seat. When he spotted the chase plane, he managed to give the pilot inside a thumb’s up, and then unbuckled himself at about 17,000 feet, deploying his parachute,” the paper reported. He was not wearing a pressure suit, yet survived the minus 70 F temperature and 50,000-foot freefall."

Wow, what a story! I was not aware the SS2 test vehicle had ejection seats. None of the pictures I've collected ever showed such a feature, so I'm going to attribute that discrepancy to poor quoting from the Washington Post (unless someone else can enlighten us).

I met Pete Siebold a couple times while working as Scaled. He was developing special avionics for SS1 at the time. As I recall, he also developed the SS1 flight simulator, which was based on X-plane. The SS1 simulator was open to pilots during an Open House that Scaled had. Quite a treat watching people fly the simulator. There were computer screens outside the four main portal windows of the SS1 simulator, so the effect was quite realistic.
 

Aesquire

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Can aero forces do that? Seems like hydraulic force would be needed.

Why does feathering work at Mach 1.4, yet not at 1.1 ?
Could have been something totally unrelated to his unlocking the lever.
You reconfigure the craft not under power and at very low air pressure, so the forces are much smaller. Not sure about the pressure density, but I suspect the real problem was that it was under power.
Changing to shuttlecock mode under power makes the craft try to pitch up. It did do so, and in some pics was actually flying backwards, briefly.

I don't know any aircraft that could survive that kind of problem. I don't know how the mechanism for changing modes is built.
 
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