typodupeerror

## SpaceShipTwo Tests Its Rocket Engine and Goes Supersonic103

ehartwell writes "It's official. This morning, after WhiteKnightTwo released SpaceShipTwo at an altitude of around 50,000 feet, pilots Mark Stucky and Mike Alsbury ignited the engine for a roughly 16-second blast. After the engine cutoff, the plane coasted back to its landing back at the Mojave airport. Virgin Galactic tweeted that the pilots confirmed 'SpaceShipTwo exceeded the speed of sound on today's flight!' Its predecessor, SpaceShipOne, first went supersonic December 17, 2003."
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## SpaceShipTwo Tests Its Rocket Engine and Goes Supersonic

• #### Next step (Score:4, Funny)

by Anonymous Coward on Monday April 29, 2013 @02:17PM (#43583101)

So after exceeding the speed of sound the next step is the speed of light? ;-)

• #### Re: (Score:3)

There are a few intermediate steps. Going from the speed of sound to the speed of light is more than an order of magnitude, you realize?

Dang, I'm curious now -

299792458 m / s / 340.29 m / s = 880991.089952687

Big number, alright - but not as big as I thought. Hmmm . . .

• #### Re:Next step (Score:4, Funny)

on Monday April 29, 2013 @03:57PM (#43584253)
The speed of sound at mean sea level 15C, or the speed of sound in a vacuum? There's a big difference.
• #### Re: (Score:3)

They likely mean the speed of sound at ~50Kft, where it was released from the mothership. The exact speed really doesn't matter. They're testing stability at transonic and supersonic Mach numbers.

Woosh!

• #### Re:Next step (Score:5, Funny)

on Monday April 29, 2013 @05:24PM (#43585041)

What do you mean? A woosh at sea level or in a vacuum?

• #### Re: (Score:2)

Obviously sea level. A woosh in a vacuum would be typed like _________.

Stupid slashdot... it removes all excess white space...

• #### Re: (Score:2)

The speed of light in a vacuum or in a Bose-Einstein condensate? There's a big difference :-)

-Gareth

• #### Re: (Score:2)

It ain't a real spaceship until you can see the Cherenkov radiation.

• #### Re: (Score:2)

speed of sound in a vacuum

I'd love to see someone break that :)

• #### Re: (Score:2)

Screw warp speed, go plaid!

• #### Re: (Score:2)

So after exceeding the speed of sound the next step is the speed of light? ;-)

Yep, and you get a free lifetime subscription to the "space nutter club" . After all, it's just engineering.

• #### Speed? (Score:5, Interesting)

on Monday April 29, 2013 @02:26PM (#43583213)

Why is it taking Virgin Galactic so long for development? Is it a financing or technical issue?

SpaceX was founded in 2002 and is already making re-supply missions to the ISS. Granted that's not quite the same as human spaceflight but it seems like there's a lot faster advancement occurring at SpaceX than at Virgin Galactic.

• #### Re:Speed? (Score:5, Insightful)

on Monday April 29, 2013 @02:35PM (#43583349)
It is safety issue. There's a world of difference between creating an unmanned rocket for resupply and creating a fleet of passenger space ships.
• #### Re:Speed? (Score:5, Insightful)

on Monday April 29, 2013 @02:41PM (#43583421)

SpaceX will be ferrying people soon enough.

There is a world of difference between hops up to 100 miles and actually going into an orbit.

• #### Re: (Score:3, Interesting)

SpaceShipTwo has a top speed of approx 1200 m/s, whereas low earth orbit is on the order of 8000 m/s.
• #### Re:Speed? (Score:5, Insightful)

on Monday April 29, 2013 @02:44PM (#43583471) Homepage Journal

Why is it taking Virgin Galactic so long for development? Is it a financing or technical issue?

SpaceX was founded in 2002 and is already making re-supply missions to the ISS. Granted that's not quite the same as human spaceflight but it seems like there's a lot faster advancement occurring at SpaceX than at Virgin Galactic.

They are approaching it from a cost-is-everything perspective, instead of an orbit-is-everything perspective. The SpaceX supply missions run at least \$20,000 per orbited kilo. For a person to buy a ticket, even if they were treated as cargo, would cost in the \$1.5M range. For Virgin Galactic to say that they will get a human up and down (safely) for around 1/10th that price, requires approaching the problem a lot differently (for example, a multi vehicle setup).

• #### Re: (Score:2)

Virgin Galactic is not saying they will get a human up and down to orbit safely for around 1/10th that price.

SpaceShipOne took humans to "space", but it seems to have been designed and developed in a fraction of the time it's taken them with SpaceShipTwo. Both had to deal with having a man-rated craft. Both had to deal with getting to "space", or 100km altitude. I'd imagine the bulk (if not all) of the design work was done before SpaceShipOne's launch, so I'm really having a tou
• #### Re: (Score:2)

Virgin Galactic is not saying they will get a human up and down to orbit safely for around 1/10th that price.

SpaceShipOne took humans to "space", but it seems to have been designed and developed in a fraction of the time it's taken them with SpaceShipTwo. Both had to deal with having a man-rated craft. Both had to deal with getting to "space", or 100km altitude. I'd imagine the bulk (if not all) of the design work was done before SpaceShipOne's launch, so I'm really having a tough time understanding why building the second iteration is taking so much longer.

I am not an expert in this field but some observations are apt: 'Two is a pilotable, larger craft whereas 'One was a smaller, shoot-up-parachue-down craft. The design differences are pretty big; they surely could have been working on the design for 'Two the whole time, but not much of the work on 'One carried over.

• #### Re: (Score:1)

Then what was the point of One? Was it not a prototype that is representative of the intended final design?

If the only thing the X Prize did was encourage a giant pissing contest without directly resulting in real advances in affordable human spaceflight, then the crown for "Most Awesome Ansari" will have to go from Anousheh and Amir all the way back to Aziz.
• #### Re: (Score:3)

I am not an expert in this field but some observations are apt: 'Two is a pilotable, larger craft whereas 'One was a smaller, shoot-up-parachue-down craft. The design differences are pretty big; they surely could have been working on the design for 'Two the whole time, but not much of the work on 'One carried over.

One would expect design differences given the larger size of SpaceShipTwo, the greater need for reliability as a passenger carrying vehicle instead of a prototype, and various performance and safety issues that were discovered with SpaceShipOne or with the 2007 accident (that killed three people and set back the attempts to develop a propulsion system for SpaceShipTwo).

So given that, I think a lot of the work on SpaceShipOne carries over. They have the same basic design of both the carrier aircraft and t

• #### Re: (Score:2)

Why is it taking Virgin Galactic so long for development? Is it a financing or technical issue?

SpaceX was founded in 2002 and is already making re-supply missions to the ISS. Granted that's not quite the same as human spaceflight but it seems like there's a lot faster advancement occurring at SpaceX than at Virgin Galactic.

They are approaching it from a cost-is-everything perspective, instead of an orbit-is-everything perspective. The SpaceX supply missions run at least \$20,000 per orbited kilo. For a person to buy a ticket, even if they were treated as cargo, would cost in the \$1.5M range. For Virgin Galactic to say that they will get a human up and down (safely) for around 1/10th that price, requires approaching the problem a lot differently (for example, a multi vehicle setup).

I never understood why not just do balloon to as high as a balloon goes and back.. would be lot cheaper. and do it the jump way. I'd rather pay for that than the near-space jump with virgin galactic.

anyhow, seems just like a big waste of money all and all. sure, it's cheaper. but it's still useless.

• #### Re: (Score:1)

SpaceX was founded on the the "cost-is-everything" perspective as well. Elon's whole purpose in founding SpaceX was to substantially reduce the costs of payload to orbit. BTW, Falcon 9.1 prices to orbit are currently ~\$4000/kg, while Falcon 9 Heavy should be half that, also if they are successful recovering and reusing stages, prices should drop below \$1000/kg
• #### Re:Speed? (Score:4, Interesting)

<themovingfinger@gmail.com> on Tuesday April 30, 2013 @09:21AM (#43589779)

Why is it taking Virgin Galactic so long for development? Is it a financing or technical issue?

SpaceX was founded in 2002 and is already making re-supply missions to the ISS. Granted that's not quite the same as human spaceflight but it seems like there's a lot faster advancement occurring at SpaceX than at Virgin Galactic.

They are approaching it from a cost-is-everything perspective, instead of an orbit-is-everything perspective. The SpaceX supply missions run at least \$20,000 per orbited kilo. For a person to buy a ticket, even if they were treated as cargo, would cost in the \$1.5M range. For Virgin Galactic to say that they will get a human up and down (safely) for around 1/10th that price, requires approaching the problem a lot differently (for example, a multi vehicle setup).

For Virgin, I don't think it's a financing or technical issue, because the purpose of Virgin Galactic is marketing for the Virgin brand, not producing a fleet of passenger-carrying spaceships. It puts Branson's brand in front of geeks, and geeks are a legitimate market demographic who can be manipulated by marketing propaganda just like any other market demographic. After all, smart geeks like to think they are investing their money in smart, geeky ways. As long as Branson keeps up the appearance of creating that fleet, he wins -- geeks will be able to cite Virgin Galactic in defense of the presence of any Branson-tainted investment in their portfolio, even if Virgin Galactic never puts another single human in space.

For SpaceX, cost-is-everything is indeed one driving factor, but getting payload tariffs as low a possible is a means to an end, not the end itself. Unlike Branson, Musk is a neo-industrialist who is deliberately and successfully following in the footsteps of Harriman, Vanderbilt, Carnegie, and Rockefeller. He is using technology to create a self-financing infrastructure that will enable the (lucrative, he expects) exploitation of off-planet resources, in almost the exact same way his predecessors used technology 125 years ago to create the infrastructure necessary to exploit terrestrial resources (and along the way created the social, political, and economic system that put America at the top of the industrial food-chain for nearly a century.) Musk's game plan is thus materially little different than that of any robber baron from the late 19th century. It remains to be seen whether or not history will repeat itself -- I haven't heard any manifest-destiny claims being issued from Musk's PR department yet, but I imagine it's only a matter of time, if he sticks to his current plan.

• #### Re: (Score:2)

You're right. It's much more difficult. You need around two orders of magnitude more fuel to actually make orbit.
• #### Re: (Score:2)

Even more aptly, it only took 3 years for SpaceShipOne to go from concept [scaled.com] to first powered flight [wikipedia.org]. And a little less than an year after that to complete the X-prize. SpaceShipTwo has taken three times as long to get to the same point in development. I know that building the craft for commercial customers and not experimental jet pilots would take some extra time, but I figured most of that would be testing related, and they would have gotten to this point long ago. That engine explosion must have really set

• #### Re: (Score:2)

Why is it taking Virgin Galactic so long for development? Is it a financing or technical issue?

SpaceX was founded in 2002 and is already making re-supply missions to the ISS. Granted that's not quite the same as human spaceflight but it seems like there's a lot faster advancement occurring at SpaceX than at Virgin Galactic.

Politics, mostly. There's plenty written up on what has been going on, if you do some Google searching.

A lot of it boils down to the difference between a company that is good at research, and a company that is good at manufacturing. Another factor was the explosion in New Mexico, which set things back and reportedly demoralized some of the key people involved.

• #### Re: (Score:2)

Why is it taking Virgin Galactic so long for development?

Space is hard.

• #### Re: (Score:2)

Scaled Composites had to develop two separate vehicles... The lift vehicle and the sub-orbital vehicle. There was a substantial amount of testing for the White Knight 2 to complete before they could start testing the sub-orbital vehicle.
• #### Re: (Score:1)

Why is it taking Virgin Galactic so long for development? Is it a financing or technical issue?

They're still working on the list of hairdressers and telephone sanitizers.

• #### WhiteKnightTwo, SpaceShipTwo (Score:1)

by Anonymous Coward

theycutdownonspacestosaveonfuelcosts?

• #### Re: (Score:2)

Sign writers charge by the word.

• #### Re: (Score:2)

Supercalifragilisticexpialidocious?
• #### Terribly Exciting - 10 years ago (Score:3, Insightful)

on Monday April 29, 2013 @02:35PM (#43583339) Homepage Journal

When Spaceship One blasted off to win the X-Prize. I remember being very excited. I watched the launch and read as many articles about it as I could.

That was 10 years ago. Now we have SpaceX and Orbital Sciences making orbit. Tremendous new things seem possible now with Falcon Heavy and Grasshopper reusable stage coming in the pipeline. SpaceShipTwo? A bigger version of SpaceShipOne that carries passengers, but still only suborbital with no further prospects. Where is the Tier Two orbital program that Rutan hinted at? Why did it take so long to get SS2 off the ground? Did Scaled get lost and rudderless with Burt retiring? Did they lack funding? What's the deal?

• #### Re:Terribly Exciting - 10 years ago (Score:5, Informative)

on Monday April 29, 2013 @02:44PM (#43583467)

SpaceX charge rather more than \$200,000 per seat to fly into space. And there's a big difference between NASA 'man rating' and being safe enough to routinely fly tourists; if SS2 flew daily and was as 'man rated' as the shuttle, they'd kill everyone on board every two months.

• #### Re: (Score:2)

Nasa had an astronaut death rate of 1.5%. For every 100 Astronauts that went into space on top of a giant explosion 1.5 were killed.

While no where near safe for the general population. It is comparable to every other man rated space fairing vehicle that uses semi controlled explosions to move.

• #### Re:Terribly Exciting - 10 years ago (Score:5, Interesting)

on Monday April 29, 2013 @02:48PM (#43583533) Homepage

I got a chance to meet Rutan a few years ago here in Colorado Springs at the USAFA - he spoke passionately to the cadets about the fact that when he started in aerospace the speed/power/altitude curve was bent upwards, and then after the shuttle it bent back over itself into decline (think about the fact that the SR-71 is the fastest aircraft in the world right now, and we haven't built a new one in a LONG time). Then he talked about his work, building year after year on the EZ and other aircraft to become an expert at composite fabrication and aircraft.

The gist of his talk was loosely - `get out there and do it - and this time STAY`. I'm pretty sure if you asked him why Scaled is running so "slowly" you'll get an earful about how much they've learned. What is missing from Scaled is the money and industry savvy that Elon pumped into SpaceX. Scaled was really only made to win the X prize, and even with Brason on-board hyping the hell out of it, Rutan is not a "run flat-out" kind of guy. A big difference between the software engineer mindset (Elon) and the test-pilot "I damn sure hope this plane flys" aerospace engineers.

• #### Re: (Score:2)

"SR-71 is the fastest aircraft in the world right now"

That we know of. There have been hints at other craft going faster, namely Aurora [wikipedia.org]

• #### Re: (Score:2)

Slashdot sure has changed, most of the people posting don't even comprehend the difference between what they did and say a concord.

• #### Re: (Score:2)

Actually, Orbital Sciences has been putting payloads into orbit since 1990, using converted ballistic missiles.
• #### it was mostly hype, man... (Score:1)

Did they lack funding? What's the deal?

They suck at space. Space is a bitch of a place to try to do business. Operational decisions **must** be made by engineers and astronauts...not businesspeople or actuarial risk analysts.

First, I was happy to see SS1, but it was also sad. Why? It was 40's technology dressed up with plastic and circle windows. SS1 was mostly **hype**

2. SS1 was a C- business concept at best. Hype aside, people need stuff in space, so even though we all knew SS1 was kinda silly, we figured

• #### Re: (Score:2)

We go to asteroids and the moon and we *fucking mine that shit*

And once we have it, what do we do with it?

Getting space ore down to Earth in a rocket cargo hold will pay off only if it's solid gold/platinum, last I checked the ballpark numbers.

De-orbiting entire asteroids the cheap way is not particularly fun for those near the impact site.

Leaving it in space for colonists to build with literally begs the question: what would be the economic reason those people to live in space? To mine more stuff so they can build more homes for more miners? That's a nice pyramid sche

• #### Re: (Score:2)

Leaving it in space for colonists to build with literally begs the question: what would be the economic reason those people to live in space? To mine more stuff so they can build more homes for more miners? That's a nice pyramid scheme, but we can already run those cheaply on Earth.

The stock space nutter response is that they will build starships. Which would be fine if (a) we could build starships and (b) there was anything within reasonable human travel distance worth visiting.

• #### Re: (Score:3)

Al Stern at SETIcon II said these suborbital flights have generated interests among certain researchers because cost is reasonable and researchers themselves can fly and conduct the experiment. Some sub-orbitals flights might be too low and others get to that sweet spot. Stern also made some mention about sub-orbital flights into areas where meteors break-up which seems to imply gather samples. Although this can be done by remote control, Al Stern says look at university professors, they go to the basement

• #### long term goal? (Score:1)

What is their long term goal for this program? Surely it can't be just taking tourist to the edge of space and back. Could this lead to high speed air transport or something?

• #### Re: (Score:1)

Branson wants to make Virgin Galactic profitable just doing tourism - think about it, for the moment he's got an exclusive market for the sub-orbital hops, and a turn-time/serviceability of SS2 being a day or less. This is a much better revenue stream than the one-a-quarter rocket launches for SpaceX, and is widely scalable at \$100k or less a pop. Far more seat occupiers at that rate than the \$20M per Dennis Tito ratio for the full-orbit experience.

• #### Space is easy. Orbit is hard. (Score:2)

Flying to Orbit, with an update for SpaceShipOne
http://world.std.com/~swmcd/steven/stories/orbit.html [std.com]

• #### These flights have nothing to do really with space (Score:5, Interesting)

on Monday April 29, 2013 @03:12PM (#43583803)
I think the "Space" part of it is a side show to what Virgin is really pushing for.

The bigger goal, IMO is being able to enable flight from the US/Europe to Australia in a matter of hours by a "plane" jumping into low Earth orbit and circling the globe in 2 hours. Imagine being able to "jump" to the other side of the Earth in an 1 hour? A 2 hour flight to China? Australia? Europe?

It takes 88 minutes in LOE to circle the globe.

It would simply be revolutionary. IMO that is the near term end goal of Branson's interest in space flight. I think the "manned space flights" are tangential to what the immediate goals are. Hammering out the science to allow cheap cross earth flights, is simply incredible.
• #### Re:These flights have nothing to do really with sp (Score:5, Informative)

on Monday April 29, 2013 @04:33PM (#43584615)
There is a vast difference between SSO, or even SST, and what you propose. SSO and SST just go straight up and straight back down. There is very little ground track in their flight envelope. In order to get to orbit, you need to go straight up, and then go about double that to really get out of the atmosphere, and then tack on around 8km/s velocity. You're looking at a few dozen times more energy, and around a hundred times more fuel. A sub-orbital transcontinental flight won't need quite that much, but you're still way up there in comparison. Add in the fact that you're actually going to need a real thermal protection system for re-entry. They're not even in the ballpark.
• #### Re:These flights have nothing to do really with sp (Score:4, Interesting)

on Monday April 29, 2013 @06:26PM (#43585583)

They're not even in the ballpark.

Energy is not hard to come by. SpaceShipOne generated about a sixth of the delta-v it'd need to reach orbit. I consider that fairly close given the type of engine and relatively low mass fraction. SST is supposed to have slightly better performance in that regard. But neither is intended for this particular role.

But I think naysayers are overstating the difficulty of more delta v and a different thermal protection system. Sure, it might need a radical vehicle redesign. But guess who demonstrated that they can design such suborbital vehicles?

• #### Re:These flights have nothing to do really with sp (Score:5, Informative)

on Monday April 29, 2013 @07:34PM (#43586133)
I think you're understating the difficulty of more d-V. Six times the d-V doesn't simply mean six times the fuel. Energy is proportional to velocity squared, so you immediately need thirty-six times the energy. When you factor in the exponential behavior of the rocket equation, and the fact that you need yet more fuel just to take up the additional fuel needed to accelerate the spacecraft itself, your fuel consumption balloons fast.
• #### Re: (Score:2)

Finally, you mention the rocket equation! I find it interesting how the people who talk about how hard it is, tend to be weak on the actual math. So you have some inkling of the difficulties. Now, use a more efficient engine, for example, LOX/kerosene optimized for vacuum.

I also was a bit in error. Delta-v for SpaceShipOne was a quarter what they needed to get in orbit. Using LOX/kerosene would boost that delta-v by about 40%. Sure, you still need a high propellant to dry mass ratio (something like 12 or
• #### Re: (Score:2)

I also was a bit in error. Delta-v for SpaceShipOne was a quarter what they needed to get in orbit.

You were right the first time. SSO only reached 112km, which is roughly equivalent to 1.5km/s of d-V. Between altitude and orbital velocity, LEO is around 9.5-10km/s. That's 6.5 times higher.

• #### Re: (Score:2)

You were right the first time. SSO only reached 112km, which is roughly equivalent to 1.5km/s of d-V.

Hmmm, when I last did the calculation [nasaspaceflight.com], I thought there was considerable horizontal velocity (of 1,200 m/s, but that turns out to be the maximum speed during the trajectory). That is quite wrong since the trajectory was almost straight up. It does simplify the calculation though.

So let's take your number of 1.5 km/s of delta-v for the highest trajectory. For that trajectory, the engines burned for 80 seconds straight up (I had 65 seconds which I believe was for the first flight which barely passed 100km).

• #### Re: (Score:2)

In order to get to orbit, you need to go straight up, and then go about double that to really get out of the atmosphere, and then tack on around 8km/s velocity.

But you don't need to go orbital, just a ballistic. While the trajectories of some of the longer flights like Sydney to London are approaching the energy needed for orbit, there are plenty of medium length ones like LA to NY, or NY to London that are well within the grasp of a scaled-up version of SS2.

• #### Re: (Score:2)

I think the "Space" part of it is a side show to what Virgin is really pushing for.

The bigger goal, IMO is being able to enable flight from the US/Europe to Australia in a matter of hours by a "plane" jumping into low Earth orbit and circling the globe in 2 hours. Imagine being able to "jump" to the other side of the Earth in an 1 hour? A 2 hour flight to China? Australia? Europe?

It takes 88 minutes in LOE to circle the globe.

It would simply be revolutionary. IMO that is the near term end goal of Branson's interest in space flight. I think the "manned space flights" are tangential to what the immediate goals are. Hammering out the science to allow cheap cross earth flights, is simply incredible.

Sadly I'm not sure the bulk market is there. You used to be able to hop on a plane in London and land in New York 3 hours later. Now it takes over 7.

I could see a market for a charter - sometimes as a business you need someone to be somewhere, and it's costing you \$100k/hour that they aren't there, but that would require a lot of planes to be in key places ready for immediate launch (NY, LA, London, Tokyo, Singapore)

• #### Re: (Score:3)

Yes, it's a real pity that there's no way of instantly communicating with people on the other side of the world.

Seriously, apart from the military, who the cares whether they can fly half way round the world in an hour for a face to face meeting?

If it could be done for the same price as a current air fare, fair enough, we'd all like to get to our holiday destination quicker. But when you're talking about \$100K+ a trip, it seems like a tiny and uninteresting market.

• #### Yawn (Score:2, Insightful)

by Anonymous Coward

The SR-71 was deployed in 1964 and had an operational elevation limit of 80,0000ft. What excactly are we breaking out the champaign for?

• #### Re: (Score:2)

The SR-71 was deployed in 1964 and had an operational elevation limit of 80,0000ft. What excactly are we breaking out the champaign for?

It's Cham-pag-en

• #### Re: (Score:2)

The SR-71 was deployed in 1964 and had an operational elevation limit of 80,0000ft. What excactly are we breaking out the champaign for?

It's Cham-pag-en

When pointing out a spelling mistake, it's customary to provide the correct answer.

Hint, it's not "Champagen".

• #### Did it really break the sound barrier? (Score:1)

Looking at the flame out of the back of the craft it looks more like a raw fuel dump than something that will sent the spaceship into supersonic flight.
• #### 16 sec burst (Score:1)

sounds like kittyhawk. interesting to think that first steps are so tentative decades later. we haven't changed that much, it seems.

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