Virgin Galactic Now Aiming for Spaceflight in February

Sir Richard Branson speaks to a group of future astronauts at the FAITH Hangar of Virgin Galactic in Mojave, CA September 25, 2013 in Mojave, CA. (Credit: Virgin Galactic)
Sir Richard Branson speaks to a group of future astronauts at the FAITH Hangar of Virgin Galactic in Mojave, CA September 25, 2013 in Mojave, CA. (Credit: Virgin Galactic)

Virgin Galactic is now hoping to get SpaceShipTwo into space on a test flight in February, according to multiple sources who attended the company’s gathering of future astronauts in Mojave on Wednesday.

Virgin Group CEO Richard Branson told about 300 future passengers that February is the new target date for having the six-passenger spacecraft fly above the Karmen line located at an altitude of 100 km (62 miles).

One attendee said that Branson didn’t project a lot of confidence about the February date. Overall, the British billionaire seemed rather subdued during in his opening remarks to attendees, lacking some of the enthusiasm he had shown at previous Virgin Galactic events, sources said.

Others who are familiar with the troubled development of SpaceShipTwo’s hybrid engine were less confident in Branson’s prediction. A flight in February is possible, they said, but it might not occur in 2014.

Virgin Galactic had been hoping to fly SpaceShipTwo into space by the end of this year. After the vehicle’s first powered test flight on April 29, Branson boldly predicted that he and his two children, Sam and Holly, would be on the first commercial flight on Christmas Day.

Branson’s prediction caused a lot of eye rolling by people in Mojave who are familiar with the complexity of flight test. Few people believed it would be possible to complete the test program and obtain regulatory approvals to begin commercial service in less than eight months.

The new plan is for Scaled Composites to complete the test program next year, obtain a launch license from the FAA, and to begin commercial service by the end of 2014.

A spaceflight would be a key milestone in a flight test program being run by Scaled Composites, which built SpaceShipTwo and its WhiteKnightTwo carrier aircraft.

SpaceShipTwo has made two powered flights to date using hybrid nitrous oxide-rubber engines that have fired for 16 and 20 seconds. Virgin Galactic has never been specific about the length of a full-duration firing, but sources say it exceeds one minute.

The problem is that despite public claims to the contrary, the nitrous oxide-rubber hybrid has never been hot fired on the ground at full duration, sources indicate. And the engine is not powerful enough even when fully fired to get SpaceShipTwo into space with any actual payloads (i.e., six wealthy passengers).

Even as Scaled Composites has pursued the flight test program and Virgin Galactic has issued optimistic flight predictions that commercial flights are only months away, the two companies have been secretly working on alternatives to the nitrous oxide-rubber engine they have been using to explore SpaceShipTwo’s flight envelope.

Sources report that the development of alternative hybrid designs has been running into trouble. An engine that used nitrous oxide and nylon exploded on Scaled Composites test stand on May 17. The nozzle and rocket casing were thrown clear and the test stand was wrecked. The composite tank holding the nitrous oxide did not explode, but it was damaged to the point where it could not be reused.

Scaled said they were testing an experimental, non-flight engine into which they had introduced flaws on that day. Sources say this is true; however, the explosion and wrecked test stand were not part of the test plan.

There has been work done on developing a liquid-fuel engine, which many experts see as a better long-term solution. A hybrid engine must be replaced after each flight, a process that is a delicate, complicated and expensive. A robust, reusable liquid engine would allow SpaceShipTwo to be refueled and fly again the same day.

It is not clear whether a liquid-fuel replacement is in active development at the moment, or how long it might take to get one ready for flight test on a SpaceShipTwo vehicle.

  • therealdmt

    Well, pretty much everyone figured that the FAA certification and paperwork process would take longer than Branson calculated in his infamous Christmas prediction.

    The real problem becomes if the rocket engine is a real problem. That sounds like a years-long delay if they have to go to a completely new engine type. Unless it can be bought off the shelf, such an engine would have to be custom designed, tested, certified and then manufactured at the necessary quality _and_ price.

    And then it would have to be installed in a Space Ship Two (and it’ll have to fit essentially perfectly), and then the whole aircraft will have to be reflown and retested throughout its flight regime with the new engine to get certified.

    Hopefully they can make do with their current hybrid rocket design in the interm. Heck, a partially loaded flight (just 1 or two passengers) would be even more exciting for the lucky passengers who would get to go up and mess around in zero G with that big interior all to themselves! And that could by Virgin the time they’d need with their remaining customers to get the final engine right.

    Man, oh man. Hopefully the current engine is sufficient!

  • therealdmt

    That should have been “buy”, not “by”!

  • Whatwaswas

    Branson is getting increasingly aware of the possibility that he is funding a dead horse and that in the end nothing will come of it. His first investment mistake. My guess is that XCOR with its Lynx suborbital will prove to be the all out winner.

  • Some Old Desert Rat

    How far along is Lynx? I never really hear much* out of XCOR. I know they planned on launching Lynx in 2010 (at least according to Wikipedia), then pushed it back to 2013 and now they’re uprooting their shop to Texas sometime soon.

    Can anyone speculate on when they’ll begin test flights?

    *Aside from the glimpse into their work they provided on their blog a few weeks ago.

  • Hemingway

    Is any other company working on a nitrous oxide-rubber hybrid engine as opposed to a liquid-fuel engine? Why must a hybrid engine be replaced after each flight? Thanks!

  • Some Old Desert Rat

    I believe that the motor is actually being produced by Sierra Nevada Corporation. Scaled just bolts them onto the vehicle.

    A hybrid rocket is fueled by a plug of rubber. The rubber burns during firing. After the rubber burns the motor is “out of gas” and must be refilled with new rubber. The cheapest and easiest (and safest) way to do this is to pull out the remains of the rubber plug and its case and replace it with a new one. The oxidizer is stored in a separate non-disposable tank and is simply refilled after flight. It’s more accurate to say that “half of the hybrid engine” must be replaced after each flight.

    Here’s a pic of the solid part of the motor being loaded:

    And here’s a pic of the oxidizer tank:

  • Douglas Messier

    The FAA has never done anything like this before. Virgin Galactic is the first company to submit an application, so a lot of precedents will be set by how this application goes.

  • Douglas Messier

    The XCORians are very busy right now building the Lynx. They’ve been explaining the specifics of their work on the XCOR blog each weekday for the past few weeks. I don’t think they have updated the schedule publicly lately, but I expect they will soon.

    XCOR got hit very hard by the Great Recession, which struck at about the same time they were preparing to raise money for building the Lynx. It pushed back the schedule a couple of years.

  • Tonya

    With all these rumours about problems with the hybrid engine, is there any reason to also be concerned for the Dream Chaser?

  • wikkit

    I think Dream Chaser’s engines are smaller. Hybrids scale poorly, so that means theirs are easier.

    However, they have an extra challenge: hybrids are not known for highly predictable thrust curves. Dream Chaser has two engines set far apart on the vehicle. Any difference in thrust will result in a yawing force on the vehicle that will have to be compensated for.

  • wikkit

    In a liquid fueled rocket, if I said “I replaced the engine”, no one would interpret that to mean that I replaced the fuel or oxidizer tanks. The same is true of a hybrid: the oxidizer tank is not part of the engine. The combustion chamber is.

    So to Doug’s point, the entire engine is disassembled after every firing. The casing and nozzle may or may not be reusable. The main valve and injector probably are reusable. So most of the hybrid engine is replaced after every flight.

  • Robert Horning

    Branson could have simply stuck with SpaceShip One and done some very minor refinements, but instead he insisted upon a new upsized vehicle. It will be interesting to see if that might have been a good or bad decision.

    Unfortunately, the history of technological innovations tends not to favor the very first guy to do something unique and original… although people in that “first wave” right behind that first guy do tend to end up very wealthy and successful.

  • Aerospike

    The same line of thoughts is also my biggest concern about Dream Chaser.

    Not that I’m any kind of expert on rocket engines, but after everything I’ve seen regarding hybrids, especially the engine firings from the SpaceShip1 Project and even more so the hybrids fired by Copenhagen Suborbitals, I really have a “bad” feeling about Dream Chaser’s “main” Engines.

    I hope that I’m wrong.

  • Some Old Desert Rat

    I’ve always sort of pictured it as a solid rocket motor with an externally fed oxidizer and a fuel grain held in a convenient cartridge that is replaced after each use.

    So, yes, the entire engine is disassembled after every flight, but it should also be pointed out that there are basically only two parts. Disassembling a liquid engine is much more complicated than disassembling a hybrid rocket.

  • wikkit

    Also not true. Disassembling a pressure-fed engine, which would be comparable to a pressure-fed hybrid, involves unbolting one ring at the head.

    Disassembling this hybrid, in comparison, involves an abrasive cutoff wheel because the thrust chamber and nozzle are bonded together with composites. That very pretty–very expensive–big composite tube is discarded after every launch.

  • Some Old Desert Rat

    I don’t think this is what they actually do (unless Sierra Nevada is grossly incompetent in composite design and fabrication).

    Just imagine if after every launch they would:

    1. Cut off the end of the rocket
    2. Scrape out the charred remains
    3. Somehow jam another rubber plug back in there
    4. Bond everything back together in such a way that it doesn’t fail during the next launch.

    It just doesn’t make any sense. God knows how unsafe that would be too – composites are kind of fragile and repeated grinding and bonding just isn’t a good idea. Yes, composites are expense, but they aren’t *that* expensive.

    I linked to a photo of the fuel grain being loaded. To me it just looks like you replace the “cartridge” and you’re off again. There’s no real disassembly to speak of.

  • Hug Doug

    just as a side note, those are excellent pictures!

  • Douglas Messier

    The Dream Chaser rockets are smaller, more like SSOne engines, and they do have that challenge you mentioned.

  • Douglas Messier

    However you define it, this is not cheap.

  • wikkit

    That’s rather my point, they don’t really disassemble the motor after a flight. They unbolt the fuel/thrust chamber/baffle/nozzle assembly from the injector head, throw that entire structure away, and bolt on a new one. No less complex than a liquid rocket engine disassembly, yet dramatically less reusable.

  • Tonya

    Thanks for the answers. It sounds as though there might be a risk if there’s an asymmetry in performance of the two engines. Though I’d say the same risk has also been true for many launch vehicles that use twin solid boosters.

    If the test data shows that the engines perform consistently, and that they don’t have problems such as sizeable chunks of rubber randomly breaking off during combustion, it should be safe. I guess the question is how much testing is needed to demonstrate that.

  • Thanks for that.
    In point of fact studies have shown that ShipShipTwo if switched to liquid-hydrogen fueled could on its own reach suborbital space without the need for a carrier aircraft. Moreover the engine needed is already existing in the engine for the cryogenic upper stage of the Ariane 5, though you may need two of them. This liquid fueled engine would also be reusable at least up to ten flights unlike the hybrid which needs to be replaced each flight.
    Not having to use the carrier aircraft WhiteKnightTwo would make both development cost and flight costs cheaper. And not having to spend money on developing a new engine would be also a big cut in the development cost. Being reusable the liquid fueled engine would probably be cheaper per use than the hybrid also.
    Keep in mind also that reusable liquid fueled engines were used from the very earliest times of rocket powered human flight in the X-15. This cut drastically the costs per flight.

    See the articles below. They describe using the in-development Vinci hydrogen-fueled engine, but two copies of the hydrogen engine now used on the upper stage of the Ariane 5 would be adequate to the task.

    SpaceShipTwo could be single stage to suborbit says ESA firm.
    By Rob Coppinger on April 29, 2010 4:24 PM

    Reusable Space Plane Idea Intrigues Europeans.
    Rob Coppinger, Contributor
    Date: 01 May 2012 Time: 04:30 PM ET

    Bob Clark

  • Paul451

    Underneath your comment, it says “Edit”. If you click that, you can go back into the edit window and make any changes you want.

  • Paul451

    At the very least, he could have continued to operate SS1 to generate income during the SS2 development.

  • Some Old Desert Rat

    >No less complex than a liquid rocket engine disassembly

    I guess we’ll just have to agree to disagree.

  • Douglas Messier

    There are a number of safety concerns about hybrid engines. I remember talking with some people before the April 29 test, and the general feeling was that we hoped they were flying because they were ready and that they didn’t blow up the vehicle in flight.

    The biggest concerns with the nitrous/rubber design are:

    a. Chunks of rubber getting stuck in the engine throat. That would cause an over pressure and then an explosion. Loss of vehicle.

    b. Burn through. It burns through the rocket casing and causes severe damage to the ship. Possible loss of vehicle.

    c. Nitrous oxide ignition. It can just go off on its own (as it did in the 2007 explosion that killed three people and injured three others). Loss of vehicle.

    They may switch to a different engine type (nitrous oxide and nylon, for example). Or to a liquid engine. It might be possible to drop a liquid engine into the existing design without having to make any major changes in the air frame.

  • Some Old Desert Rat

    “rich-guy cheap” 🙂

  • Robert Horning

    The SS1, in terms of its capabilities as of the Ansari X-Prize competition were concerned, was rather limited. It definitely would have needed some substantial modifications for passenger flight. There were also some stability issues that never did get worked out, including a nearly tragic flight that luckily was recovered but could have been far worse.

    Getting the SS1 to be operational for routine flight operations would have been quite expensive and have taken time, resources, manpower, and attention away from the development of SS2. At the time, Burt Rutan was even asked if he could simply fly SS1 for a couple more flights, and his reply was that it was still an experimental aircraft and didn’t want to risk even the potential that it could somehow fail, that instead it rightly belonged in a museum (now in DC at the Air & Space Museum).

    Ticket prices for going up past the Kármán line would have been much more expensive on the SS1 than is anticipated with SS2 as well. If anything, I think this economic argument together with what Richard Branson saw as an extremely small cabin interior for SS1 (if you are spending that much money for free-fall, should you just be confined to a fighter-jet cockpit type seat?) SS2 has some room to really move around the cabin and enjoy the flight experience.

    At the time, it seemed better to simply dump the SS1 design altogether, hence why I suggest that the jury may very well still be out as to if that was the best decision Branson made instead of doing as you suggest to get the SS1 operational. It would be arguable that operating SS1, even an improved “SS1 v. 2.0”, would never even be profitable.

  • wikkit

    I specifically said “Disassembling a pressure-fed engine, which would be comparable to a pressure-fed hybrid…” You’re comparing apples to oranges. SS2 is not a turbopumped hybrid, so it’s unreasonable to compare it to a turbopumped liquid.

    I have a 4000lbf-thrust LOX/Methane pressure fed engine sitting on my coffee table that I built for Nasa, and I assure you that it’s not at all complex to disassemble.

  • gopher652003

    Ha, I misread that as saying you have a 4000 pound engine sitting on your coffee table, and I was truly impressed. Was going to ask for a picture of that coffee table.

  • Some Old Desert Rat

    Ok – I feel like I’m starting to beat a dead horse here, however:

    Are you saying that both your a 4000lbf-thrust LOX/Methane pressure fed engine that you built for NASA and SS2’s hybrid rocket engine are so simple to disassemble that saying “the entire engine is disassembled after every firing” makes a fairly trivial task sound more complicated than it is?

    Unfortunately, determining whether or not you’ve “replaced the engine” in hybrid vs. liquid rockets is also an apples to oranges comparison that clearly won’t be resolved in this thread.

  • Emrik Storensen

    You should share a picture of that engine. Really you…you built it for NASA. Which contract was that for again?

    You have the machining resources and the finances. Didn’t you work for armadillo? Is it your unique design or rather bit and pieces of ‘borrow technology’. How does one casually come by an ITAR controlled piece of hardware. Did you mean that armadillo built it for NASA and you simply ‘borrowed it’

  • wikkit

    I would have happily explained the story of how CH4K ended up on my coffee table, but you just casually accused me of stealing a big rocket engine. So instead, I’ll welcome you to go to hell.

  • Carolynne Campbell

    Sir Richard has a long history of bad investments – especially when technology is involved. This time he has bet with a lot of O.P.M. (other people’s money), namely Abbaar Investments.
    He might rescue the project by switching to liquid oxygen. Amroc, among others, did quite well with Lox/HTPB. It would require quite a stretch to get it in, but the lighter oxidiser load and improved performance could, possibly, rescue the thing.
    The Dreamchaser’s biggest problem may well turn out to be the space community’s reaction to the idea of a motor that spits high velocity chunks of rubber into low-earth orbit, thereby wrecking other bits and pieces already dodging bullets in a sea of accumulating debris.

  • Doug Weathers

    Could they align the engines so their thrust vectors go through the vehicle’s center of mass?

  • Douglas Messier

    It looks like early next year for initial test flights:

    “We are building the vehicle right now, and hope to begin flight tests
    early next year, and by late 2014 if things are on schedule, the winner
    will fly,” said Andrew Nelson, Chief Operating Officer of XCOR, the firm
    building the Lynx.

    Read full story

  • peter