Author Topic: Space Ship Two - General Thread (Read 748587 times)

Star One · « **Reply #1320 on:** 02/22/2014 04:27 pm »

Speaking as a lay person what type of engine should they have gone for, and if this is the type they were supposed to use why didn't they?

Danderman · « **Reply #1321 on:** 02/22/2014 08:34 pm »

Branson: the man who fell to earth

http://www.afr.com/p/national/arts_saleroom/branson_the_man_who_fell_to_earth_zcxzKOJy5cHZ6dOGO3AIoN

And so it begins .......

Kabloona · « **Reply #1322 on:** 02/23/2014 12:59 am »

Quote from parabolicarc:

"Actually, Sierra Nevada Corp. has found a way to stabilize the engine. "

Doug, is this new info? Does it mean they have proven the nylon hbrid is stable? Or that they have found a way to stabilize the rubber hybrid?

docmordrid · « **Reply #1323 on:** 02/23/2014 03:29 am »

Quote from: Danderman on 02/22/2014 08:34 pm

Branson: the man who fell to earth

http://www.afr.com/p/national/arts_saleroom/branson_the_man_who_fell_to_earth_zcxzKOJy5cHZ6dOGO3AIoN

And so it begins .......

You mean and so the echo chamber begins. This isn't an original article.

Quote

This is an edited extract from Branson: Behind the Mask by Tom Bower

FutureSpaceTourist · « **Reply #1324 on:** 02/23/2014 06:40 am »

The guardian had another long article on Friday about Richard Branson, VG and SS2: http://www.theguardian.com/science/2014/feb/21/jon-ronson-virgin-galactic-richard-branson-future-atronauts

A bit more balanced than some (uncritical) media commentary.

Branson certainly seems to be going for broke this year, with all the recent media coverage. Maybe he felt his hand was forced, with 10th anniversary coming up, but clearly he must believe there's a reasonable chance of a flight this year.

If SS2 can't make 100 km it'll be interesting to see whether existing ticket holders accept it. Maybe they'll be offered the opportunity to either fly 'now' (ie next year) or wait for an upgraded SS2 in a couple of (3?) years?

parabolicarc · « **Reply #1325 on:** 02/23/2014 06:51 pm »

Quote from: Kabloona on 02/23/2014 12:59 am

Quote from parabolicarc:

"Actually, Sierra Nevada Corp. has found a way to stabilize the engine. "

Doug, is this new info? Does it mean they have proven the nylon hbrid is stable? Or that they have found a way to stabilize the rubber hybrid?

The video they released of a rubber-nitrous test at the end of last year showed a much more stable burn. However, the engine requires lengthy and complex changes to SS2 and there is a significant performance hit.

Tests are continuing on the nitrous-nylon engine to try to get one that would be both reliable and able to provide better performance.

Beyond that, I'm not sure how much more I can say.

Kabloona · « **Reply #1326 on:** 02/24/2014 03:40 am »

Quote from: parabolicarc on 02/23/2014 06:51 pm

the engine requires lengthy and complex changes to SS2 and there is a significant performance hit.

Wow that is bad news. The nylon hybrid must not be far enough along in development if they're planning to make such drastic changes to stick with an underperforming rubber hybrid. More disappointment.

Robotbeat · « **Reply #1327 on:** 02/24/2014 12:09 pm »

Or, they'll manage it just fine. I'm not worried about it. Then again, I'm not a customer and would probably fly on a Lynx if I were in the market (cheaper... and likely to be MUCH cheaper once they start flying regularly).

butters · « **Reply #1328 on:** 02/24/2014 04:09 pm »

Quote from: Star One on 02/22/2014 04:27 pm

Speaking as a lay person what type of engine should they have gone for, and if this is the type they were supposed to use why didn't they?

There's really no correct answer, because VG did/does honestly believe that the mechanical/conceptual simplicity of the pressure-fed hybrid design would not only carry the day but also resolve what they perceived to be fundamental economic problems with liquid rocket engine. Following from this premise, I would suggest that the main thing they could have done differently would have been to have multiple smaller fuel chambers fed by a common oxidizer system. This may have avoided the problems they encountered trying to scale up the hybrid engine.

Otherwise, their options would have been limited. They could have used a Merlin engine, but it might have been difficult to convince investors that replacing the engine every 10 flights would be economical for suborbital tourism. Of course, SS2 as we know it isn't exactly gas-and-go, but it's easy enough to hand-wave over the part where they R&R the fuel chamber between flights.

yg1968 · « **Reply #1329 on:** 02/24/2014 04:58 pm »

Quote from: parabolicarc on 02/23/2014 06:51 pm

Quote from: Kabloona on 02/23/2014 12:59 am
Quote from parabolicarc:

"Actually, Sierra Nevada Corp. has found a way to stabilize the engine. "

Doug, is this new info? Does it mean they have proven the nylon hbrid is stable? Or that they have found a way to stabilize the rubber hybrid?

The video they released of a rubber-nitrous test at the end of last year showed a much more stable burn. However, the engine requires lengthy and complex changes to SS2 and there is a significant performance hit.

Tests are continuing on the nitrous-nylon engine to try to get one that would be both reliable and able to provide better performance.

Beyond that, I'm not sure how much more I can say.

Have they decided which of these two options they wish to pursue?

parabolicarc · « **Reply #1330 on:** 02/27/2014 11:56 pm »

Quote from: yg1968 on 02/24/2014 04:58 pm

Quote from: parabolicarc on 02/23/2014 06:51 pm
Quote from: Kabloona on 02/23/2014 12:59 am
Quote from parabolicarc:

"Actually, Sierra Nevada Corp. has found a way to stabilize the engine. "

Doug, is this new info? Does it mean they have proven the nylon hbrid is stable? Or that they have found a way to stabilize the rubber hybrid?

The video they released of a rubber-nitrous test at the end of last year showed a much more stable burn. However, the engine requires lengthy and complex changes to SS2 and there is a significant performance hit.

Tests are continuing on the nitrous-nylon engine to try to get one that would be both reliable and able to provide better performance.

Beyond that, I'm not sure how much more I can say.

Have they decided which of these two options they wish to pursue?

Both, apparently. There was another engine test today that was witnessed by George Whitesides and members of his team. Read the story: http://www.parabolicarc.com/2014/02/27/spaceshiptwo-engine-test-mojave/

Also, I was on The John Batchelor Show last night discussing the engine status and flight test plans for later this year. John has a 15-minute Hotel Mars segment he does with David Livingston of The Space Show every Wednesday. It deals with all measures of space news and events.

For details, go to http://www.parabolicarc.com/2014/02/27/appearance-john-batchelor-show-archived/

Kabloona · « **Reply #1331 on:** 03/05/2014 04:50 pm »

Meanwhile, the publicity machine grinds on:

http://winklevosscapital.com/posts/78649481042

Star One · « **Reply #1332 on:** 03/07/2014 02:49 pm »

More PR from Mr Branson.

http://www.digitalspy.co.uk/showbiz/news/a556133/richard-branson-lady-gaga-space-concert-most-exciting-thing-ever.html

Lurker Steve · « **Reply #1333 on:** 03/07/2014 04:23 pm »

Quote from: Star One on 03/07/2014 02:49 pm

More PR from Mr Branson.

http://www.digitalspy.co.uk/showbiz/news/a556133/richard-branson-lady-gaga-space-concert-most-exciting-thing-ever.html

Not much real news, although I did learn that Kate Winslet is married to a guy named Ned RockNRoll, who just happens to be Richard Branson's nephew. Unfortunately, their kid Bear is taking her last name.

Don't expect much real news from DigitalSpy...

Star One · « **Reply #1334 on:** 03/07/2014 05:14 pm »

Quote from: Lurker Steve on 03/07/2014 04:23 pm

Quote from: Star One on 03/07/2014 02:49 pm
More PR from Mr Branson.

http://www.digitalspy.co.uk/showbiz/news/a556133/richard-branson-lady-gaga-space-concert-most-exciting-thing-ever.html

Not much real news, although I did learn that Kate Winslet is married to a guy named Ned RockNRoll, who just happens to be Richard Branson's nephew. Unfortunately, their kid Bear is taking her last name.

Don't expect much real news from DigitalSpy...

That was kind my point about his news update & where it appeared.

parabolicarc · « **Reply #1335 on:** 03/10/2014 02:49 pm »

A couple of Virgin Galactic updates:

Reports have surfaced that Virgin Galactic has purchased hangars at a former U.S. Navy base in Puerto Rico. The facility's airport could be used as a base for space tourism in the Caribbean. It's also well situated for launching spacecraft from WhiteKnightTwo over the Atlantic.

http://www.parabolicarc.com/2014/03/09/virgin-galactic-operate-puerto-rico/

There are conflicting reports whether a deal is in negotiation or whether one has been completed. No word from Virgin Galactic.

Also, there's legislation pending on Capitol Hill that would have some major impact on Virgin Galactic's testing and operations:

http://www.parabolicarc.com/2014/03/10/mccarthy-virgin-galactic-hope-commercial-space-measure-soars/

A key provision of the bill would allow continued testing on spacecraft under experimental permits even after launch license are issued. Right now, the launch license supersedes the permit once it is issued.

Other provisions would allow WhiteKnightTwo to be considered as part of the launch system and thus permitted and licensed along with SpaceShipTwo. The measure would also allow for use of WhiteKnightTwo for crew and passenger training. The significant of that is Virgin Galactic wouldn't have to put WhiteKnightTwo through an aircraft certification process, which is time consuming and costly.