…why the relatively silence from a media savvy Virgin Group that understands the PR value of showing a rocket engine firing?
Nobody knows for sure. However, people familiar with such things thought the engine firings in the initial video looked rough. (At least from what they could see of it through the enormous cloud of dirt and dust the engine threw up.) Soon after the video was released, stories circulated that engineers at Sierra Nevada Corporation were having a hard time scaling up the hybrid engine system from the small, X-1 sized SpaceShipOne prototype to its business jet sized successor. Oscillations sufficiently severe that nobody would want to ride the vehicle.
The stories have persisted and, if anything, have grown stronger. The latest one circulating in Mojave is that the test in March didn’t go well, and that the propulsion team has decided to abandon the hybrid rocket for a liquid system. There is also a confirmed report that Virgin Galactic has formed its own propulsion team and hired the former director of SpaceX’s Texas engine testing facility — and an expert in liquid propulsion — as a member of it.
On Saturday, I asked Whitesides whether they were considering dumping the hybrid system entirely. He reaffirmed that the company are focused on hybrids for now; liquid propulsion is something that would be consider down the road.
I’ve always thought that the hybrid was a mistake. The late Jim Benson sold Burt on it for SpaceShipOne, though, and the success of the X-Prize apparently gave him the confidence to stick with it for SpaceShipTwo, despite its operational disadvantages. After the explosion in Mojave, I suggested to Alex Tai that it was a good opportunity to change course, but he said that it would cost too much in vehicle redesign, due to the different mass distribution. I’ll bet that they’re now really regretting that decision, if they have to do so anyway, because it has cost them years in schedule. Also, I wonder (assuming the rumors are true) why they’re developing their own, instead of just buying from XCOR? That was the mistake they made with the hybrid.
“There is also a confirmed report that Virgin Galactic has formed its own propulsion team and hired the former director of SpaceX’s Texas engine testing facility — and an expert in liquid propulsion — as a member of it.”
Why did the “former director of SpaceX’s Texas engine testing facility” leave Space-X?
Are they through running engine tests?
How would I know? Maybe he (or she) was offered more money? Maybe living in Mojave is preferable to McGregor? People aren’t allowed to change jobs? What difference does it make?
With a hybrid the big difficulty is getting the regression rate right so the mixture ratio is correct..
If one had a clean view of the rocket plume one could judge the quality of the mixture ratio, ie is the plume burning on the fringes outside of the rocket, does this burning very with time, or cycle?
The only video every released has the motor pointing at a big dirt pile. With the big dirt plume it makes it impossible to judge the operation of the rocket motor.
Rand Simberg Says: May 24th, 2011 at 8:53 am
“How would I know? Maybe he (or she) was offered more money?”
So Branson hired a key player away from Musk (maybe)?
“Maybe living in Mojave is preferable to McGregor?”
Been both places, it would be a very measured choice.
“People aren’t allowed to change jobs?”
Nothing I said would lead anyone to the conclusion that I was implying that.
“What difference does it make?”
Just usually not a good thing when a company loses a key manager when (superficially at least) activity in that managers area (Falcon Heavy) would be about to ramp up.
We don’t know how key the manager was. They have a team. No one is irreplaceable.
Note also that it didn’t say it hired him away from SpaceX. He was characterized as a “former director.”
Interesting story. It’s plausible that they could be having development problems with the engine; the low pace of test firings and the lack of public release of signs of success this late in the game would fit with that. Then again, they might simply be not releasing info on an engine that’s working fine. It’s possible, albeit hard to explain if so.
That said, any replacement liquid-propellant engine for SpaceShip Two is likely to be a new development, not an off-the-shelf buy – someone will correct me if I’m wrong, but I’m not aware of any existing ~60Klbf (or useful fraction thereof) liquid biprop engines out there that use nitrous for the oxidizer and operate at relatively low pressure. (The reasons for these specs are left as an exercise for the student.)
If in fact Virgin et al are switching away from hybrid propulsion, they might reasonably want to keep the new liquid propulsion development in-house where they have maximum control over this critical-to-them process. The other side of that coin would be going to an outside contractor for existing rapid development expertise. But if they think they can successfully hire that expertise in, well, the argument for doing it in-house could be compelling.
The wild card in all this could be what, if any, engine development help might they call on from their airframer’s parent, Northrop-Grumman? The Spaceship Company is a joint venture between Scaled and Virgin; Scaled’s parent company’s resources might or might not be on call. (And might or might not be affordable, N-G being at heart a government cost-plus contractor.)
One of the changes after the accident was to add metalic lining to the nitrous tank and operate sub-cooled with he pressurization.
Given these changes one could switch from Nitrous to peroxide with a big boost to propellant density and almost no changes to the oxidizer tank.
A peroxide bi-prop runs at a very skewed O:F ratio such that you could put the fuel in tubular tanks that go where the big hybrid grain used to go. This would require minimal changes to the SS2 airframe.
It could almost be a drop in replacement.
A Biprop would also be MUCH lower cost to operate.
If they have a problem with the hybrid why aren’t they buying from XCOR? I think I know more about that than I should, but let’s just say that may not be an issue forever.
The real headache is that whoever they get a liquid engine from it means a major redesign on the vehicle. If they do that, and Branson can still stick with the effort, they might end up labeling the present vehicle “‘SS2A’ from which we got valuable test info on larger scale feathered flight.”
Pure speculation…
Remember that Barber Nichols Inc (BNI) has already produced a 34,000-lb thrust peroxide and kerosine engine for an unknown customer (probably Blue Origin) and BNI also built the SpaceX Merlin engine turbo pumps (http://www.barber-nichols.com/products/rocket_engine_turbopumps/).
Two of these existing BNI engines on SpaceShipTwo would give it the ~ 70,000-lbs of thrust that it needs to maintain the 2.5 to 1 thrust to weight of SpaceShipOne. VG could figure out how to scale this up to 1 engine of 70,000-lbs as well.
If Virgin Galactic hired the former SpaceX propulsion manager, then he should have about 10-years or more experience with this BNI engine technology.
Scaled Composites has a lot of expertise in rapid prototyping of 1-off designs so they could probably build a new SS2 in 1 or 2 years that uses the new liquid engine(s).
When Branson says 12 – 15 months to commercial service, he just means that he and a select few people will take test rides with a highly experienced test pilot flying SS2 into space. It will take them many years after that to actually get FAA certification and to begin to fly the majority of their initial 425 customers. The customers will like this, because it will make this an exclusive experience. Branson will not meet his business target of over 5,000 to 10,000 flown by 2020.
VG probably won’t reach their 500th customer flown into space until 2020……and that is not that bad.
It will take them many years after that to actually get FAA certification and to begin to fly the majority of their initial 425 customers.
There is no such thing as FAA certification for suborbital vehicles. There is no distinction in the FAA’s mind between “he and a select few people” and “the majority of their initial 425 customers.” If the hybrid isn’t working properly, no one will fly with it, and no one will fly until they have an engine that is.
Two words – vertical integration. Ala SpaceX.
The former director of the SpaceX test facility is Thomas Markusic. He previously worked at NASA Marshall before joining Musk’s team. I haven’t been able to confirm why he left SpaceX.
SpaceX is NOT through running engine tests. There’s been a new director in Texas for a while now.
As for buying an engine from XCOR, I’m told it would take them about two years to produce one if they dropped everything else they’re doing. Which they can’t. And won’t. Andrew Nelson’s confidence in XCOR’s future does not appear to be hype. They’ve got a busy year ahead.
Sounds like they should raid a museum for a Reaction Motors XLR99 from an X-15, which is throttleable, generates 70,000 lbf vac, and it is already man-rated. The downside is that the XLR99 uses anhydrous ammonia, now used in meth labs, so they’d have to use the rocket to escape all the drug crazed zombies that attack their facilities.
Rand,
Just type FAA certification and SpaceShipTwo into Google, and you will have some information to base your opinion on.
Branson will probably fly himself and a few employees on SpaceShipTwo, and a good test pilot can maybe fly SS2 into space despite the rough hybrid engine performance. This will be very different from routine operations with less experienced pilots.
Remember that SS1 only flew above 100-km on 3 occasions, and most of its rocket-powered test flights looked dangerous enough to scare the test pilots and their families.
If Branson flies into space in 2012 on SS2, then he will have a PR success, and VG will probably have another liquid propelled SS2 ready for test in 2013. Whitesides said that VG is starting construction of the 2nd WK2 and SS2, so don’t be surprised if there are major modifications (like liquid engines) that you will see in the SS2 design in 2013.
Branson can handle the PR, but this could be a financial hit for VG.
Just type FAA certification and SpaceShipTwo into Google, and you will have some information to base your opinion on.
I don’t have to type anything into Google to know that the FAA has no statutory authority to certify space vehicles. That is not my “opinion.” It is a fact. I do this for a living.
Branson will probably fly himself and a few employees on SpaceShipTwo, and a good test pilot can maybe fly SS2 into space despite the rough hybrid engine performance. This will be very different from routine operations with less experienced pilots.
You have no idea what you’re talking about.
Doug Messier,
Thomas Markusic might have known Whitesides back from their days at Princeton.
Thomas Markusic is the person who presented details of the SpaceX Merlin-2 engine, Raptor LH2 engine, and Falcon XX heavy lift designs in power points widely circulated and discussed within the media in summer 2010. Elon Musk had to give interviews to tell the media that he disagreed with Tom’s call for nuclear thermal rockets.
As a NASA-Marshall employee he probably had experience with Barber Nichols and their liquid engines in addition to his time at SpaceX.
He might be perfect for the job at VG.
D. Messier Says: May 24th, 2011 at 12:13 pm
“The former director of the SpaceX test facility is Thomas Markusic. He previously worked at NASA Marshall before joining Musk’s team. I haven’t been able to confirm why he left SpaceX.
SpaceX is NOT through running engine tests. There’s been a new director in Texas for a while now.”
Thank you for the actual information.
Rand,
Below is a link to a Space News article that briefly discusses some of Virgin’s plans with the FAA and how they plan to incrementally increase their flight rate for commercial services.
http://www.space.com/9565-private-spaceshiptwo-heads-territory.html
VG also has a job posting for a person to work with the FAA on licenses and other certifications.
I am not saying that you are wrong in your statements, but I do think that you are probably missing the point of what I am saying.
VG has many options to make a PR declaration within the next 12 to 15 months that they are in commercial service, and this is why VG is consistent in providing a schedule that claims a 2012 start for commercial launches. VG can build a completely different SS2 with a liquid engine within 2 years that becomes their true operational vehicle while they have a test pilot fly the difficult hybrid motor into space over the next 2 years. Remember that the ME-262 jet fighter was flown as a propeller plane for 2 years before the jet engines were ready.
VG keeps saying that they will be ready next year and that they will eventually receive FAA licenses and approvals, so maybe VG has some flexibility that you do not know about.
I have never said that VG won’t get a launch license. I said that the FAA doesn’t certify vehicles, and that they make no distinctions between “test pilots” and VG employees, and passengers. VG may make such a distinction if they wish, but the FAA won’t care.
Rand,
VG will make many such distinctions, and the FAA will care about these distinctions. This is why VG wants to hire a full time employee to handle the FAA.
I am not trying to disagree with you.
VG has many options in declaring commercial service in 2012 with a potentially difficult hybrid engine, and VG has many options to work with the FAA and tort lawyers (i.e. ambulance chasing litigation specialists) on these issues.
The hybrid engine was always a dead end for VG, and they should have taken on a liquid engine design a long time ago. VG can and they should move to a liquid engine propelled SS2 for their operational vehicle.
It is interesting to note that Blue Origin’s recently flown New Sheppard PM-2 module probably has the avionics and lift performance (PM-2 weighs 75 tons with 55 tons of propellant) to place an un-fueled SS2 on a sub-orbital trajectory above 100-km. PM-2 could also lift the Dream Chaser above 100-km.
VG will have a full-time person to handle the FAA because dealing with the FAA for launch licensing is a full-time job, regardless of whether or not the company wants to make distinctions that the FAA will find consider meaningless.
Maybe VG should pay Blue Origin to launch their SS2 into sub-orbital space on PM-2.
Maybe Sierra Nevada should pay Blue Origin to launch Dream Chaser into sub-orbital space on PM-2. This could prepare Dream Chaser for an orbital PM-3 flight with Blue Origin versus an Atlas V.
Maybe Boeing should pay Blue Origin to launch CST-100 into sub-orbital space on PM-2. This could prepare CST-100 for an orbital PM-3 flight with Blue Origin versus an Atlas V.
Has ULA announced when they will start to manufacture Atlas V lower stages and upper stages in their factory in Alabama yet? Will ULA reenter the commercial market and sell Atlas V rockets at commercial prices for the CCDEV2 teams relying on them?
Blue Origin and SpaceX were smart to bring liquid engine development in house. They have a lot more control over their costs and schedule than others.
VG’s interest in getting the FAA involved is purely anticompetitive barrier raising red-tape-ism.
That said, I have long suspected that the “tire fire” propulsion of SS1 would not scale well and it would be a financial hole for Virgin to crawl out of depending on how long they persist in pushing the dead horse into the gate to comply with their green propaganda (despite the fact that XCOR’s engines are much cleaner burning than the hybrid system).
Rand,
I agree with you.
They also need to work with FAA on reentry and many other issues.
VG wants to eventually have FAA certification like aircraft for liability reasons, but this will take a very long time. Burt Rutan discussed this in a speach a few years ago.
FAA AST has been working with Congress for decades on what they do and do not have authority over, and sub-orbital and orbital vehicle certifications, licensing, etc will play out over many decades more.
They also need to work with FAA on reentry and many other issues.
No, they don’t. Entry is only an issue for orbital vehicles. It is an intrinsic part of a launch license for suborbital flight, and one that all suborbital vehicles have to deal with.
Please quit digging.
When did the comments on here get as retarded as the places Rand often posts his mainstream articles?
Once again the consequences of the artificial deadline of the X-Prize raises its head.
http://www.thespacereview.com/article/1829/1
[[[Although Rutan attended the St. Louis event in May 1996 that formally announced the X PRIZE and was the first to register for the competition, Allen notes in the book that their effort was not originally designed to win the prize: in fact, the original vehicle design was apparently only intended to carry a single person. Only when the Ansari family donated the money in 2002 needed for the “hole-in-one” insurance policy that would fund the prize purse did Scaled modify the vehicle to carry three people as required by the prize rules. That redesign caused the price of the project to more than double, from $9 million to $19 million, according to Allen.]]]
I said it before and I will say it again. The X-Prize didn’t advance sub-orbital tourism, it set it back by forcing Scaled Composites to cut corners and rush SpaceShipOne, while sending most of the viable competitors after a false target.
And now they are doing the test flight program they would have done with SpaceShipOne, except for the X-Prize.
[[[Allen said that original plans called for one flight a week for five months after winning the prize, but those plans were cancelled after Branson expressed his interest in the project and the Smithsonian’s National Air and Space Museum sought to display SpaceShipOne.]]]
But they have no engine because they were rushed with the X-Prize deadline into a bad choice.
Now that Burt Rutan is retired and in Idaho you wonder how long Sir Richard Branson will let Virgin Galactice bleed money before he pulls the plug and goes for the orbital market.
My guess is he will do so as soon as XCOR flies. Sir Richard does not like being second.
Rand, one thing I have not seen clarified is the certification requirements for White Knight Two. It is an aircraft that will be used to carry passengers for hire, both in SS2 and as a trainer for future SS2 passengers. Any other airplane that carries people for hire has to be certified and I somehow don’t think the FAA will look the other way just because WK2 is used to carry SS2. Certifying an airplane is a massively expensive undertaking. Even getting a 4 seat private plane certified for production can cost over $50 million, much less a 4 engined twin-fuselage jet.
My understanding is that it flies on an experimental certificate, and is the carrier aircraft for the space vehicle, which operates under AST rules. The passengers are therefore regulated under AST, and the informed consent agreement. Will Whitehorn swore to me three years ago that he had an agreement with George Nield that he could carry passengers in it on its own, but I didn’t believe him then, and I don’t now, because George has no authority to make any such guarantee — it would be under the jurisdiction of AVR. Though there could be a loophole for training under an experimental certificate. That’s certainly the route I’d be pursuing. Standard Part 127 (or perhaps a different part, given its size) certification would be out of the question if they want to keep it affordable.
“I said it before and I will say it again. The X-Prize didn’t advance sub-orbital tourism, it set it back by forcing Scaled Composites to cut corners and rush SpaceShipOne, while sending most of the viable competitors after a false target.”
Maybe.
My understanding is that if anyone is at fault for the VG problems it is Branson himself for insisting on a larger vehicle. Supposedly SS1 was perfectly adequate for flying tourist passengers. VG could have been flying tourist flights for years now instead of sinking time and money into SS2.
VG could have been flying tourist flights for years now instead of sinking time and money into SS2.
Or both. They could have ordered a few SS1.1’s with some minor safety mods learned from the X-Prize flights, then they would have had a learning platform. Even if they ended up losing money on the flights due to the low seat count, high turnaround costs, and lack of a true production line; they would likely have gained it back many times on operational experience, design lessons-learned, and the ready availability of a suborbital testbed for subsystem-level vetting. Remember, after a ~year of flight tests they haven’t even gone transonic, gone high-Mach/low-Q, or re-entered yet. Much of that could have been tested subscale on a modified SS1.
More macabre, but just as importantly, they may have weathered the inevitable first fatalities better with such a craft, marketed as experimental from the start, vs. the current learjet on meth. Really, if you count the ’06 explosion as first fatalities… consider if the composite NOX tank exploded in 2006 on the way to 100km, it would have made bigger news… but I’m not sure it would have shown the company in a worse light.
> Paul Breed Said:
> May 24th, 2011 at 10:06 am
>
> One of the changes after the accident was to add metalic lining to the nitrous tank and operate sub-cooled with he pressurization.
> Given these changes one could switch from Nitrous to peroxide with a big boost to propellant density and almost no changes to the oxidizer tank.
Nitrous is pretty dense also – 1.22 gm/cm3 at boiling point, presumably denser, subcooled. Not that much advantage for peroxide there.
Looked at another way, SS2 is already set up to carry enough liquid N2O oxidizer to fly the mission, and a liquid biprop motor would be no less efficient (likely somewhat more efficient) than the hybrid it’d be replacing. I won’t argue whether there’s a performance boost to be had from peroxide; I don’t have enough data – but if their objective is to get flying as quickly and simply as possible, I don’t see why they’d change their oxidizer.
>
> A peroxide bi-prop runs at a very skewed O:F ratio such that you could put the fuel in tubular tanks that go where the big hybrid grain used to go. This would require minimal changes to the SS2 airframe.
Also true for nitrous, is my understanding, and exactly my thinking in predicting they’d stick with nitrous – typical nitrous O:F ratios are very high, so enough liquid fuel to fly the mission could probably be stored in the SS2 boattail volume in a way that mimics the weight and balance of the hybrid grain.
I know you’re used to peroxide, but overall, I don’t see the advantages in this application to justify the additional complications of switching from the oxidizer they’re already set up for. Additional complications equal additional time & money, neither of which they likely have to spare at this point.
>
> It could almost be a drop in replacement.
>
> A Biprop would also be MUCH lower cost to operate.
Agreed on both these points, for either peroxide or nitrous. (Or for that matter various other room temp liquid oxidizers – but those tend not to be things you want to deal with near paying passengers…)
Brad,
Yes, the customer, VG, also had unrealistic requirement and I would argue that the X-Prize hype contributed to it.
But you need to read in his book how worried Paul Allen was that it would crash. Especially when the extra dead weight for the X-Prize flights was added. One reason Paul Allen noted for his agreeing to retired SpaceShipOne was he was afraid their luck would run out with it. Yes, the test pilots deserve real kudos for flying it so well.
So a Spaceshiptwo would have been needed regardless, a modification that fixed those issue before entering service. And why the original smaller one person test vehicle flown in a proper test flight program would have worked far better in advancing sub-orbital commerce.
Actually, for the additional money required to meet the X-Prize requirements they could have probably built 2-3 airframes and done a fairly extensive flight test program that really advanced the field as was the case with the X-1 and X-15.
Roga,
[[[Or both. They could have ordered a few SS1.1′s with some minor safety mods learned from the X-Prize flights, then they would have had a learning platform.]]]
Even more important they could have started pioneering the Sub-Orbital SRE markets that firms are not realizing are far bigger and more stable then tourist markets. And since no tourists would be aboard, just crew, you would not have had the PR issue if you have if you kill a tourist in a crash.
But again, the X-Prize with its narrow focus on tourism distracted folks from the real markets and proper development. Which is why it set the field so far back rather then moving it forward.
So how long before we are able to agree the X-Prize was actually a failure? Anyone?
Henry,
I did not realize that cooled nitrous was so dense.
The negates a lot of the benefit of switching.
I see two other benifits to peroxide:
Regen cooling is really easy and robust, you have a huge volume of coolant (peroxide) and its almost as good as water for cooling.
The other real benefit is with a decomposed peroxide motor you don’t need an ignition system, start the peroxide first.
Once its running well in mono prop mode, then add fuel, no additional ignition system or hard start safety interlocks required.
Also if the cat pack is working there is no possibility of a creating a liquid liquid explosive mixture.
For these benefits one has the hassle of the peroxide black magix catalyst voodo. In reality the cat pack is of constant thickness, so the cat pack percentage of motor mass goes down as the motor gets larger.
Sounds like the greater experience base out there with peroxide liquid biprops might be one reason to switch – lots of people out there have done them successfully, and there’s probably an existing design somewhere that’d be a decent starting point for developing a match for the app.
On the other side, there’s the existing SS2 investment in nitrous handling, and no inherent show-stoppers in a nitrous liquid biprop (that I’m aware of, at least).
Assuming they’re actually going for a new propulsion system, it’ll be interesting to see what they actually do. Having worked the logistics of such projects, I’d still be inclined to guess they’d stick with the oxidizer they know. We’ll see!