Space Ship Two - General Thread

[mr. mark]

I guess it's a question of belief or priorities. Why would Virgin Galactic continue to operate a system that was underperforming and had no end game? Why would Virgin Galactic continue to assert that the system is just fine and will do the job. Why would Virgin Galactic continue to use the engine to expland SS2's flight envelope? So it comes down to who you believe. The company who is developing the product and whose reputation is on the line or others who for whatever reason may dissagree with that development plan.

I can see that point of view, but I can also see the opposite point of view - why hasn't SS2 flown to space? why hasn't there been a full duration burn of the current iteration of the SS2 engine?

The answer to those questions are basic. Why SS2 has not flown to space? Virgin Galactic is slowly expanding the flight envelope while evaluating the SS2 system as a whole. That takes time. Why has there been no full duration burn of the current SS2 engine?  That question is incorrect. There has been a full duration burn of the current SS2 engine on it's test stand. A video showing that burn was recently shown by Virgin Galactic.

[Borklund]

I guess it's a question of belief or priorities. Why would Virgin Galactic continue to operate a system that was underperforming and had no end game? Why would Virgin Galactic continue to assert that the system is just fine and will do the job. Why would Virgin Galactic continue to use the engine to expland SS2's flight envelope? So it comes down to who you believe. The company who is developing the product and whose reputation is on the line or others who for whatever reason may dissagree with that development plan.

I can see that point of view, but I can also see the opposite point of view - why hasn't SS2 flown to space? why hasn't there been a full duration burn of the current iteration of the SS2 engine?

The answer to those questions are basic. Why SS2 has not flown to space? Virgin Galactic is slowly expanding the flight envelope while evaluating the SS2 system as a whole. That takes time. Why has there been no full duration burn of the current SS2 engine?  That question is incorrect. There has been a full duration burn of the current SS2 engine on it's test stand. A video showing that burn was recently shown by Virgin Galactic.
<snip>

1. It's taken a lot of time indeed. Why haven't they gone to space yet it they want to start commercial operations in a few short months time? Wouldn't it be prudent to show that it works? They have the necessary license to do so, and the FAA must surely expect them to at least show that capability once before granting them an operational license, no?

2. Okay great, they showed a full duration burn on a test stand. Why don't they want to perform a full duration burn in flight with a pilot and ballast for 6 passengers and go to space for 6 minutes? They have shown the airframe and every other facet of the flight envelope working correctly, several times now.

What possible reason could they have for not demonstrating this capability to regulators, investors and customers? Could there be an ounce (or a tonne) of truth behind what Doug is saying?

[Star One]

I do worry that there does seem to be a lack of willingness to give VG the benefit of the doubt that maybe other companies discussed elsewhere enjoy. Perhaps a more level playing field in this area would be more conductive to discussion?

[Kabloona]

I do worry that there does seem to be a lack of willingness to give VG the benefit of the doubt that maybe other companies discussed elsewhere enjoy. Perhaps a more level playing field in this area would be more conductive to discussion?

Some people here are apparently willing to take what VG says in public at face value, while others are not. And some of the people in the "not" camp are particularly well-informed (not speaking of myself, of course).

A "level playing field," it seems to me, is simply an open forum (here) where views and information may be freely exchanged and evaluated on the merits of the information itself and the credibility of the speaker. If some of that information or opinion is contrary to VG's public statements, would it "level the playing field" to bar it from this discussion?

In that case, we may as well only allow official statements from VG to be posted here.

I for one appreciate parabolicarc's posts here and tend to believe him rather than VG's "wall of sunshine" PR. Evidently you do not, and that is your prerogative, too. But let's not shoot a messenger who may, in fact, have a valid message.

[mr. mark]

"2. Okay great, they showed a full duration burn on a test stand. Why don't they want to perform a full duration burn in flight with a pilot and ballast for 6 passengers and go to space for 6 minutes? They have shown the airframe and every other facet of the flight envelope working correctly, several times now."

Why, simple. They are not ready to do so yet. When they are ready we will know and they will perform it. Until then enjoy the Virgin Galactic test flights. Space is hard.

[Kabloona]

Why, simple. They are not ready to do so yet. When they are ready we will know and they will perform it...Space is hard.

And yet, when someone posits a possibly valid technical reason for the delay (problems with the propulsion system) that agrees with your premise ("space is hard") you seem to discount it as unworthy of consideration. Strange.

And to respond to something you said earlier, I don't see anyone here "disagreeing with their development plan."  I think we all wish their development plan would work, but apparently it's not or they would already be flying customers.

Unfortunately, it seems to be VG themselves "disagreeing with their development plan," because apparently they're working on a nylon hybrid that wouldn't even be necessary if the original plan (HTPB hybrid) was meeting their expectations.

[Star One]

I do worry that there does seem to be a lack of willingness to give VG the benefit of the doubt that maybe other companies discussed elsewhere enjoy. Perhaps a more level playing field in this area would be more conductive to discussion?

Some people here are apparently willing to take what VG says in public at face value, while others are not. And some of the people in the "not" camp are particularly well-informed (not speaking of myself, of course).

A "level playing field," it seems to me, is simply an open forum (here) where views and information may be freely exchanged and evaluated on the merits of the information itself and the credibility of the speaker. If some of that information or opinion is contrary to VG's public statements, would it "level the playing field" to bar it from this discussion?

In that case, we may as well only allow official statements from VG to be posted here.

I for one appreciate parabolicarc's posts here and tend to believe him rather than VG's "wall of sunshine" PR. Evidently you do not, and that is your prerogative, too. But let's not shoot a messenger who may, in fact, have a valid message.

I don't take what VG say at face value but neither do I take at face value those with opposing viewpoints.

[sdsds]

when someone posits a possibly valid technical reason for the delay (problems with the propulsion system) that agrees with your premise ("space is hard") you seem to discount it as unworthy of consideration. Strange.

I think the point of the recent thread trimming was that there was too much speculation on an update thread.

At least, that's my speculation! ;-)

It's a truly fine line. Updates shouldn't have to come from the "official" sources of information. If they did, the thread would be inherently biased. So ... is there a published source of information about engine difficulties that hasn't yet been mentioned here?

[docmordrid]

Why the kerfufel over nylon? It's been in play since 2010.  If nylon delivers lower emissions that would be in line with Virgin's standing environmental policy regarding fuels.

http://m.voices.yahoo.com/virgin-galactic-responds-study-alleging-environmental-7284842.html

Virgin Galactic Responds to Study Alleging Environmental Impact of Space Tourism

Fri November 26th, 2010
>
Whitehorn complains. 'We are not allowed to discuss because of ITAR rules [International Traffic in Arms Regulations] exactly what the rocket motor was. But we're not using rubber. We're using a form of recycled nylon.'

"Virgin Galactic's own website says that its hybrid engine is using a 'rubber compound', with a nitrous oxide oxidiser, but Whitehorn was quoted as saying that the firm was looking into nylon fuels at the spaceport opening ceremony.
>

[Kabloona]

So are you saying this report from parabolicarc is incorrect?

"Ken Brown captured these spectacular photos of a hybrid engine test at the Mojave Air and Space Port on Thursday afternoon. Scaled Composites conducted the hot fire of the nylon-nitrous oxide engine, which is being tested as an alternative to the rubber-nitrous oxide that Virgin Galactic’s SpaceShipTwo has used for three test flights, sources say."

I don't know what the truth is here. I'm just trying to find it.

[docmordrid]

My point is that they've been developing nylon for a lot longer than the current hullabaloo, and even before the flight tests. It could be for performance, it could be  for emissions, or both.  We don't know, and absent more hard data we won't. All else is kremlinology.

[Kabloona]

I just Googled "spaceshiptwo nylon" to see the earliest result I could find mentioning a nylon hybrid. This website, although apparently not highly technical, mentions the nylon hybrid (in the fourth to last para), as apparently publicized in the December 2009 unveiling event:

http://www.age-of-the-sage.org/virgin_galactic/spaceshiptwo.html

However, other news sources, reporting on the same event, mention only a rubber-based hybrid.

So, evidently, reports of a nylon hybrid were made public as early as 7 December 2009 (the date of the unveiling). Why many sources continued to report a rubber-based hybrid is unclear. Maybe VG was trying to avoid ITAR problems by mentioning only a rubber hybrid on their website. But then why would they mention the nylon hybrid at a public inveiling? It's bizarre. Perhaps they realized only later a possible ITAR problem and tried to cover their tracks.

[A_M_Swallow]

When Virgin Galactic is ready to fly passengers then they will bring all their websites and leaflets up to date.  Until then the sites will say whatever the author was told on the day he wrote it.  Different authors may have been told different things on different days.

Nothing to worry about there.  Just do not believe everything you read in the newspapers (or websites).

[Kabloona]

When Virgin Galactic is ready to fly passengers then they will bring all their websites and leaflets up to date.  Until then the sites will say whatever the author was told on the day he wrote it.  Different authors may have been told different things on different days.

Nothing to worry about there.  Just do not believe everything you read in the newspapers (or websites).

This isn't about worrying whether their website is up to date. It's about trying to understand what's going on with SS2 and whether parabolicarc's reports of a "new" nylon hybrid to replace the "existing" rubber hybrid are correct or not. The whole question of the current hybrid's (whatever it is) performance has been a big issue on this thread. If VG has been testing (and now flying) a nylon hybrid all along, instead of just starting to test fire a nylon hybrid relatively recently, as reported by parabolicarc, then at least some of his information is incorrect, and, given the controversy here over his posts, that would be rather a big deal to some people.

[vt_hokie]

I'm interested in potential implications for Dream Chaser with its hybrid propellent motors.  I've been surprised at the low flight rate to date for SS2, but I'm not going to complain about being prudent and safe.  I just wonder how often the vehicle is supposed to fly once it enters commercial service, and how soon they need to start demonstrating rapid turnaround if commercial service is to commence next year.

[Nomadd]

 You know, SS2 isn't the only rocket Virgin is working on.
http://www.aviationweek.com/Article.aspx?id=/article-xml/awx_01_23_2014_p0-657387.xml

[parabolicarc]

There's a new book out tomorrow from Tom Bower, who wrote an earlier critical biography of Branson. It's being serialized in The Sunday Times of London. The first excerpt and story focused on Virgin Galactic.

Excerpt on the explosion at the Scaled test stand in 2007:

http://www.thesundaytimes.co.uk/sto/newsreview/features/article1366953.ece

Story about the book and what it reveals:

http://www.thesundaytimes.co.uk/sto/news/uk_news/People/article1368014.ece

I'm told by someone who's read this part of the book that it has major revelations about the project and Virgin Galactic.

[John-H]

From the preview you posted:

Quote:

"The explosion was deafening. Without warning, a thunderous blast flashed across the parched scrub. More than 40 engineers fell like matchsticks onto the dirt. Swirling dust blocked out the Californian sunshine as the silence of the Mojave desert was broken by screams."

It may just be my prejudices, but I don't expect a lot of technical information from this.

[QuantumG]

It may just be my prejudices, but I don't expect a lot of technical information from this.

A great way for Virgin Galactic to respond to this would be to provide an abundance of technical information.

It's an old NASA trick: whenever people start feeling ways about stuff, just bore them with the details.

[Kabloona]

Excerpt from the book description of "Branson" by Tom Bower on Amazon/UK website:

"Helped by eyewitness accounts of more than 250 people with direct experience of Branson, Tom Bower has a uncovered a different tale to the one so eagerly promoted by Virgin’s publicists. Here is the full story of Branson: his businesses, his friendships, his ambition, his law-breaking, his drug-taking, his bullying. From the cockpit of a balloon in the clouds to the centre of Branson’s operations in his Holland Park home this book is an intimate scrutiny of exactly how Richard Branson created himself and sold himself. Tom Bower’s biography reveals Branson to be a single-minded profiteer who, while occasionally generous to others, has a fixed purpose to enhance his family’s wealth in secret off-shore trust funds. Instead of a glittering saint, Branson emerges as a devious actor, proud of plucking for his own profit the good ideas of others."

Yeah, that'll be chock-full of technical details.