SS2/WK2 news pending....

[docm]

Link....<br /><br /><blockquote><font class="small">In reply to:</font><hr /><p><b>Virgin Galactic Spaceliner: Engine, G-load News in the Offing?</b><br /><br />Keep an ear and eye out for some new developments from the outer space world of Virgin Galactic - the suborbital spaceliner group financially-fueled by Sir Richard Branson.<br /><br />During last week’s Flight School 2007 held at the Aspen Institute in Colorado, Alex Tai, Chief Operating Officer for Virgin Galactic, hinted that there’s new news regarding that dynamic duo: SpaceShipTwo/White Knight 2. Both are under construction at Scaled Composites in Mojave, California.<br /><br />Tai said the lawyers were having a final go at a “major supplier arrangement†for Virgin Galactic’s spaceship system. Word in the hallway is that the announcement likely revolves around an engine supplier for the huge White Knight 2 carrier plane.<br /><br />Also, Tai spotlighted Virgin Fuels and laboratory level propellant that “burn green†- that is, they are more environmentally friendly.<br /><br />Another tidbit wound up in my notes too. Tai suggested that something is forthcoming about the g-load profile on passengers riding SpaceShipTwo on future suborbital jaunts. Maybe less “grunt work†for those onboard in taking on reentry forces? <p><hr /></p></p></blockquote> <div class="Discussion_UserSignature"> </div>

 

[jschaef5]

I am excited for this thing to get underway so that Rutan can start working on orbital stuff (he probably already has) but thats the stuff I am waiting for.<br /><br /><br />I don't think the cost will come down low enough for these lil 10 minute flights to be worth it for a while. For the price to come down a lot, better things have to be available.<br /><br />Plus if you spend a ton of money on 1 short little flight it would be like going sky diving only once...<br /><br />I guess we just have to wait for the richies to have their fun and bring the cost down for the rest. <div class="Discussion_UserSignature"> </div>

 

[vt_hokie]

<i>Plus if you spend a ton of money on 1 short little flight it would be like going sky diving only once... <br /><br />I guess we just have to wait for the richies to have their fun and bring the cost down for the rest. </i><br /><br />Yeah, at the expected price, one flight would be like a lifetime's worth of soaring! I'll stick to Schweizer 2-33's for now, even if they don't go as high or as fast! <img src="/images/icons/smile.gif" />

 

[holmec]

Sweet <img src="/images/icons/laugh.gif" /> <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>

 

[holmec]

<blockquote><font class="small">In reply to:</font><hr /><p>I am excited for this thing to get underway so that Rutan can start working on orbital stuff (he probably already has) but thats the stuff I am waiting for. <p><hr /></p></p></blockquote><br /><br />I would expect him to be cautious and see through the success of SS2. Also he would need a customer for it, and I kind of expect it to be Virgin as well. <br /><br />Branson hinted towards this back in 2004<br />http://news.bbc.co.uk/2/hi/science/nature/3693020.stm<br /><blockquote><font class="small">In reply to:</font><hr /><p>"If it is a success, we want to move into orbital flights and then, possibly, even get a hotel up there."<p><hr /></p></p></blockquote> <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>

 

[webtaz99]

<i>I guess we just have to wait for the richies to have their fun and bring the cost down for the rest.</i><br /><br />And what technology doesn't take this path? <div class="Discussion_UserSignature"> </div>

 

[jschaef5]

Barnstormers gave pretty cheap flights. <div class="Discussion_UserSignature"> </div>

 

[jschaef5]

I did a tandem jump and afterwards wanted to get my cert to do solo jumps... like many other things time and money is not there so i added it to the list of things to do after college. This list is getting quite long.... <div class="Discussion_UserSignature"> </div>

 

[vt_hokie]

<i>A 1-26 is more fun ! </i><br /><br /><br />Haha...I'm sure it is! <img src="/images/icons/smile.gif" /> I've only taken a couple of lessons, so I'm a long way from a solo flight!<br /><br />One of these days I'd love to get a flight in one of those exotic ultra-high L/D modern sailplanes.

 

[thermionic]

I was going to say, Grobs are pretty widely available. I've heard people say they don't handle that well, 1/26's are more nimble, what would I know... But there's nothing like snuggling into a glass slipper and waggling your rudder, eh?<br /><br />I'm a little disappointed at this announcement of a pending news release. I'm wanting to see some pictures, hear a target roll-out date. It seems like they're just reminding people that the project exists. "Yep, it will have an engine. Yep, there will be fuel." Not to be critical of Scaled, I'm just really looking forward to when they start pushing the envelope again.

 

[spacy600]

Along the same lines...<br /><br />Virgin Galactic site says flight rates will be upwards of <br />one per day.<br /><br />That is a lot of Hybrid rocket motors. Who has the capacity to make so many of them? <br />When you pour the grain, you don't want it to crack right?<br />So you need some skill to make the things.<br />Dose Scaled have that ability? Who elese?

 

[thereiwas]

I liked the Swiss-made Pilatus. Think they are out of business now. Only flew it a few times, but zowee. I sure wish I hadn't left my oxygen mask in the car that fall wave day. Going up at 1,000 fpm and I had to turn back at 11,000. <img src="/images/icons/frown.gif" /> Plus my feet were getting cold.

 

[docm]

SS1 used SpaceDev rockets but with Scaled improvements using nitrous oxide + what amounts to hard rubber as fuel. <br /><br />Virgin Galactic has said they prefer an environmentally cleaner solution and I'm sure Sir Richard Branson's pockets are deep enough to build them in-house. <br /><br />My guess is either nitrous oxide or liquid oxygen + paraffin as the fuel as it can deliver many times the thrust of a conventional hybrid rocket. Paraffin is simple to cast, clean burning and is extremely inexpensive. Sounds like an ideal commercial fuel to me. <br /><br />I'd speculate it could be based on <font color="orange">Orbital Technologies</font>/a> <a target="_blank" href="http://www.orbitec.com/documents/VHRE_2006.pdf"><font color="yellow">Advanced Vortex Hybrid Rocket Engine (AVHRE)</font>/a> system which is geared to the use of paraffin fuel grains. AVHRE uses a bi-directional coaxial vortex injector for the oxidizer. <br /><br />My son and are building a small paraffin/NOx chamber right now and look to test fire in a few weeks. <br /></a> <div class="Discussion_UserSignature"> </div>

 

[PistolPete]

The good news is that sales are so good that Virgin Galactic practically doesn't know what to do with them.<br /><br />SPACE.com -- Sales Strong for First Seats Aboard Virgin Galactic's Spaceliner<br /><br />What trips me out about this whole thing is that this is not some pipe dream, this isn't Pan Am selling tickets to space just a few years after John Glenn's flight, these guys are building real hardware and have made three suborbital test flights so far.<br /><br /><br />Now, all I need to do is save up 199,999 more dollars and I'll be ready to go. <div class="Discussion_UserSignature"> <p> </p><p><em>So, again we are defeated. This victory belongs to the farmers, not us.</em></p><p><strong>-Kambei Shimada from the movie Seven Samurai</strong></p> </div>

 

[jschaef5]

EAA Airventure is coming up in a couple weeks and Rutan always gives a talk at the Theater in the Woods and for the past few years has given updates there. May hear some news then. <div class="Discussion_UserSignature"> </div>

 

[spacy600]

Has a Paraffin hybrid rocket ever flown?<br /><br />Virgin said test flights will begin about 2009.<br /><br />ps I would like it if you posted your results

 

[docm]

<font color="yellow">Has a Paraffin hybrid rocket ever flown? </font><br /><br />Yes, many times. Some of the best known;<br /><br />1. by the Mythbusters in the Confederate rocket episode. Gotta love those guys.<br /><br />2. launches by Prof. Brian J. Cantwell's Aeronautics and Astronautics team at Stanford University. Together with NASA Ames they also did 40 test stand firings which were impressive. <br /><br />Gives a whole new meaning to "All right, enough waiting around ... let's light this candle!" <img src="/images/icons/wink.gif" /> <br /><br />Ames firing below. <div class="Discussion_UserSignature"> </div>

 

[spacy600]

ok,..<br />I am not a rocket scientist, so forgive me.<br /><br />So how dose paraffin and a regular hybrid compare?<br /><br />thrust, isp, delta v, gee being felt by pilot.<br /><br />Thanks<br /><br />

 

[scottb50]

Once you got the wick lit it would be about the same. <div class="Discussion_UserSignature"> </div>

 

[docm]

Not really. The tests at Stanford etc. show paraffin hybrids to perform better than HTPB and other hybrid fuel grains; higher SI, much higher regression rates etc. <br /><br />Lockheeds 10" diameter paraffin testbed developed />5,000 lb of thrust @ NASA Stennis using the Space Propulsion Groups paraffin grain (SPG is affiliated with Stanford). Plus they have long storage times, are non-toxic, cheaper.... <div class="Discussion_UserSignature"> </div>

 

[docm]

Depends on the paraffin formulation and the creativity of the tester. Sometimes they add too much carbon, or the wrong kind. One person I know had a grain slump problem with an off batch of paraffin and fixed it by adding a few percent hot glue to the mix. I would think the big boys involved have other options. We'll see when they go public. <div class="Discussion_UserSignature"> </div>

 

[spacy600]

Can you quantify it better than better?<br />the isp is 5% better? The cost is 50% less?<br /><br />Toothpaste from china is cheaper, But I still won't buy it.

 

[docm]

First; "paraffin" is a generic term as there are numerous types ranging from what your grandmother used in the laundry to crystalline polyethylene waxes and the fuel grain mixtures they are used in. <br /><br />When measuring hybrid performance a key factor is the fuels "regression rate"; the velocity at which solid fuel burns away from the central core where the oxidizer is injected. Basically it determines thrust, overall motor performance and fuel utilization. <br /><br />Additives can affect this greatly, especially ultra fine aluminum powder which can increase the base regression rate of "paraffin" as much as 70%.<br /><br />That said the regression rate of paraffin can run 3-5 (or more) times that of HTPB, the fuel for the SpaceDev engines used in SS1 and the most common hybrid fuel to this point. <br /><br />SS1's engine produced 16,500 lb (73.5 kN) of thrust, so imagine a paraffin version. <div class="Discussion_UserSignature"> </div>

 

[thereiwas]

I'd just as soon not see more metallic powder being sprayed into the atmosphere. I believe the shuttle SRBs have this same problem.

 

[spacy600]

Virgin is going to use this by 2009?<br />It dose not sound "green" adding aluminum powder.<br /><br />So much thrust will the pilot blackout? passengers?