Space Ship Two - General Thread

[rpapo]

If you look carefully earlier in the video, that blistering or distortion seems to already have been there, before the engine ignited.  Damage in a previous flight, resulting in the addition of the reflective coating?

At least that's what it seemed like to me.

You are right, should have watched in better quality... It looks like there is an oval shaped elevation under the coating that is part of the tail.

And looking at the high resolution picture from two posts ago, I see the reason for the distortion I was seeing . . . and now I don't think it was from damage.  It appears more like a purposely raised section of the skin, perhaps to house some mechanism inside the tail.  At lower resolutions (like in the video) the distortion in the reflection looks more like warping.

[Garrett]

at 3.51, is seems to me that there is the use of the RCS

Yeah, looks like that! Well spotted. One RCS at the front (nose?) and the second looks to be emanating from the far wing. Happens concurrently with the feathering maneuvre.

[Avron]

at 3.51, is seems to me that there is the use of the RCS

Yeah, looks like that! Well spotted. One RCS at the front (nose?) and the second looks to be emanating from the far wing. Happens concurrently with the feathering maneuvre.

Strobe lights?

[Avron]

at 3.51, is seems to me that there is the use of the RCS

Yeah, looks like that! Well spotted. One RCS at the front (nose?) and the second looks to be emanating from the far wing. Happens concurrently with the feathering maneuvre.

Strobe lights?

Nope.. RCS..

[Garrett]

Hadn't heard/read much about the RCS on SS2, so a quick Google search turned up this document:

Draft Environmental Assessment for the Launch and Reentry of SpaceShipTwo Reusable Suborbital Rockets at the Mojave Air and Space Port
March 2012
http://www.faa.gov/about/office_org/headquarters_offices/ast/media/20120309_Mojave_SS2_Draft_EA.pdf

and this from within:

For exoatmospheric flight, a cold gas (compressed air) reaction control system would be used for attitude control. There would be no propellant combustion during the descent of SpaceShipTwo

[yg1968]

Branson says that they should be able to get to space this summer:

After today's successful flight, this means that we are getting closer and closer to getting to space this summer.

http://www.today.com/video/today/54039343#54039343

[Lars_J]

Branson says that they should be able to get to space this summer:

After today's successful flight, this means that we are getting closer and closer to getting to space this summer.

http://www.today.com/video/today/54039343#54039343

If people think SpaceX slip a lot, what slip factor should be applied to Branson's statements?

I hope he is right.

[Lar]

Branson says that they should be able to get to space this summer:

After today's successful flight, this means that we are getting closer and closer to getting to space this summer.

http://www.today.com/video/today/54039343#54039343

If people think SpaceX slip a lot, what slip factor should be applied to Branson's statements?

I hope he is right.

It's a constant, not a multiplier. Whatever Branson says, add 2 years.  With the singular exception of "I am getting in the ship now and we are leaving in a few minutes"

[parabolicarc]

Virgin Galactic ‏@virgingalactic
Key stats from today's #SpaceShipTwo test flight: 20 sec rocket firing, reached Mach 1.4, 71,000 ft. All were as planned.

Nice. A tad higher (2000 feet) than the September test. Could this be the beginning of regular (weekly/monthly) test flights?

No. It's not the beginning of that.

[parabolicarc]

"Richard Branson ‏@richardbranson
All the pieces are visibly in place for the start of full @VirginGalactic space flights this year http://virg.in/unh5y "

It would be great to see SS2 reach space this year.  I'm confident they can do it.

All the pieces except an engine that can get them all the way to space. That problem has not been solved yet.

[sublimemarsupial]

"Richard Branson ‏@richardbranson
All the pieces are visibly in place for the start of full @VirginGalactic space flights this year http://virg.in/unh5y "

It would be great to see SS2 reach space this year.  I'm confident they can do it.

All the pieces except an engine that can get them all the way to space. That problem has not been solved yet.

So are they just straight up lying in their press release from several days ago then?  It stated " the [engine] system has been successfully tested in ground firings to demonstrate performance characteristics and burn time sufficient to take the spaceship and its private astronauts to space"

http://www.virgingalactic.com/news/item/virgin-galactic-reaches-new-heights-in-third-supersonic-test-flight/

[parabolicarc]

The FAA's environmental assessment of WK2/SS2 flights is here.

http://www.faa.gov/about/office_org/headquarters_offices/ast/media/20120502_Mojave_SS2_Final_EAandFONSI.pdf

Total emissions from launch operations are in the table at the bottom of page 30 (page 44 of the PDF document).

You will note there are two estimates there:

HTPB/N2O  -- Nitrous oxide/rubber
Nylon/N2O  -- Nitrous oxide/nylon

That confirms what I've been reporting, that they are working on an alternative hybrid that burns nylon. Those tests are continuing. The reason is they're having trouble getting the nitrous oxide/rubber engine to work properly. They don't have confidence it can do what they claim it can do. If they did, they wouldn't be spending money on other engines.

I've corresponded with the co-author of the WSJ op-ed. He said he used the FAA estimate in that table to figure out per passenger emissions. The CO2 figures are close, so the nylon one offers little in reducing the carbon footprint:

Nitrous/rubber: 59,941
Nitrous/nylon: 58,978

Divide estimated nitrous/rubber emissions by 6 passengers, you get a figure just under 5 tons per passenger. The nylon motor is just below that. He told me that pilots don't count, just as they don't count for determining carbon footprints for passengers on conventional aircraft.

According to the document, the FAA used a similar aircraft with the same engines to estimate the carbon footprint for WK2. The assessment states they calculated for a 2-hour flight by WK2.

Hope that helps.

[parabolicarc]

"Richard Branson ‏@richardbranson
All the pieces are visibly in place for the start of full @VirginGalactic space flights this year http://virg.in/unh5y "

It would be great to see SS2 reach space this year.  I'm confident they can do it.

All the pieces except an engine that can get them all the way to space. That problem has not been solved yet.

So are they just straight up lying in their press release from several days ago then?  It stated " the [engine] system has been successfully tested in ground firings to demonstrate performance characteristics and burn time sufficient to take the spaceship and its private astronauts to space"

http://www.virgingalactic.com/news/item/virgin-galactic-reaches-new-heights-in-third-supersonic-test-flight/

My sources are very good. And they are quite explicit on this point.

[yg1968]

"Richard Branson ‏@richardbranson
All the pieces are visibly in place for the start of full @VirginGalactic space flights this year http://virg.in/unh5y "

It would be great to see SS2 reach space this year.  I'm confident they can do it.

All the pieces except an engine that can get them all the way to space. That problem has not been solved yet.

So are they just straight up lying in their press release from several days ago then?  It stated " the [engine] system has been successfully tested in ground firings to demonstrate performance characteristics and burn time sufficient to take the spaceship and its private astronauts to space"

http://www.virgingalactic.com/news/item/virgin-galactic-reaches-new-heights-in-third-supersonic-test-flight/

My sources are very good. And they are quite explicit on this point.

Yes but didn't you say that SS2 should be able to get to space with the hybrid motor just not to the official Karman line (100 km).  That would be similar to what Lynx is offering.

[Danderman]

So are they just straight up lying in their press release from several days ago then?  It stated " the [engine] system has been successfully tested in ground firings to demonstrate performance characteristics and burn time sufficient to take the spaceship and its private astronauts to space"

http://www.virgingalactic.com/news/item/virgin-galactic-reaches-new-heights-in-third-supersonic-test-flight/

The careful wording by VG concerning engine performance certainly adds to the perception that something is amiss.

[parabolicarc]

"Richard Branson ‏@richardbranson
All the pieces are visibly in place for the start of full @VirginGalactic space flights this year http://virg.in/unh5y "

It would be great to see SS2 reach space this year.  I'm confident they can do it.

All the pieces except an engine that can get them all the way to space. That problem has not been solved yet.

So are they just straight up lying in their press release from several days ago then?  It stated " the [engine] system has been successfully tested in ground firings to demonstrate performance characteristics and burn time sufficient to take the spaceship and its private astronauts to space"

http://www.virgingalactic.com/news/item/virgin-galactic-reaches-new-heights-in-third-supersonic-test-flight/

My sources are very good. And they are quite explicit on this point.

Yes but didn't you say that SS2 should be able to get to space with the hybrid motor just not to the official Karman line (100 km).  That would be similar to what Lynx is offering.

The official international boundary of space is 100 km (62.1 miles). The Air Force awarded astronaut wings to X-15 pilots who flew above 50 miles (~80 km). I don't know what standard VG is using for its claims concerning engine performance and thrust. VG has been advertising flights to 100 km and above up to 110 km as it has sold 700 reservations.

XCOR has been quite clear about the expected performance of Lynx Mark I and Lynx Mark II. Lynx Mark I is a high altitude test vehicle. Mark II is intended to reach 100 km.

That's as far as I can go at this time.

[Garrett]

Virgin Galactic ‏@virgingalactic
Key stats from today's #SpaceShipTwo test flight: 20 sec rocket firing, reached Mach 1.4, 71,000 ft. All were as planned.

Nice. A tad higher (2000 feet) than the September test. Could this be the beginning of regular (weekly/monthly) test flights?

No. It's not the beginning of that.

You're suggesting that, on top of engine burn duration issues, they are unable to do fast turn arounds for testing?

It would be great if you could explain why. I've just flicked through the recent SS2 articles on your website and I didn't come across any further details.

[Zed_Noir]

VG probably have to rebuild the SS2 after each hybrid engine burn. They need a propulsion system that can be reuse or quickly re-furbished.
 
The current powered flights are just to test fly back characteristics and SS2 deployment from WK2 IMO.

[yg1968]

"Richard Branson ‏@richardbranson
All the pieces are visibly in place for the start of full @VirginGalactic space flights this year http://virg.in/unh5y "

It would be great to see SS2 reach space this year.  I'm confident they can do it.

All the pieces except an engine that can get them all the way to space. That problem has not been solved yet.

So are they just straight up lying in their press release from several days ago then?  It stated " the [engine] system has been successfully tested in ground firings to demonstrate performance characteristics and burn time sufficient to take the spaceship and its private astronauts to space"

http://www.virgingalactic.com/news/item/virgin-galactic-reaches-new-heights-in-third-supersonic-test-flight/

My sources are very good. And they are quite explicit on this point.

Yes but didn't you say that SS2 should be able to get to space with the hybrid motor just not to the official Karman line (100 km).  That would be similar to what Lynx is offering.

The official international boundary of space is 100 km (62.1 miles). The Air Force awarded astronaut wings to X-15 pilots who flew above 50 miles (~80 km). I don't know what standard VG is using for its claims concerning engine performance and thrust. VG has been advertising flights to 100 km and above up to 110 km as it has sold 700 reservations.

XCOR has been quite clear about the expected performance of Lynx Mark I and Lynx Mark II. Lynx Mark I is a high altitude test vehicle. Mark II is intended to reach 100 km.

That's as far as I can go at this time.

But that's pretty much what you said on your website in December:

Sources indicate there are serious doubts about whether the current engine can get SpaceShipTwo all the way to a 100 km altitude with a payload. They also tell me it’s uncertain when alternative engines will be ready for flight test.

http://www.parabolicarc.com/2013/12/10/spaceshiptwo-sports-whitesides-reaffirms-2014-commercial-launch-date/#more-51035

[mheney]

So ... nothing much has changed in the past 4 weeks, then.  That shouldn't be surprising.