Virgin Galactic Clarifies Status of SpaceShipTwo Engine

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Jan2013_hybrid_hotfire

Hybrid engine test at the Mojave Air and Space Port on Jan. 23, 2013. (Credit: Douglas Messier)

The latest edition of The Lurio Report includes an update on Virgin Galactic’s testing of SpaceShipTwo. I’m reproducing the relevant excerpt from it with the original bold emphasis included:

Around the same time stories were again heard that the present engine design would not be able to attain space altitude – at least not with a full compliment of six passengers and two crew.  Will Pomerantz, VP of Special Projects for Virgin Galactic, said in response to my query that, “Mojave’s certainly full of rumors, so it’s good to have a chance to clarify.  On the basis of the great results from PF01 and PF02 [the first two powered flights], coupled with continued ground testing, we do expect the present hybrid motor to be capable of carrying passengers into space.  As always, we’ll continue to look at a variety of ways to improve the motor’s performance and cost-effectiveness.”  (Later Pomerantz confirmed that he was referring to a full complement of passengers and crew when using the hybrid motor.)

He added that while Scaled is not working on any liquid engines Virgin Galactic is, though only for the LauncherOne orbital rocket which will be released from the WhiteKnightTwo (WK2) aircraft.

This is really interesting. Let’s dissect this statement one clarification at a time.

Around the same time stories were again heard that the present engine design would not be able to attain space altitude – at least not with a full compliment of six passengers and two crew.

Those are my stories.1 I am, as near as I know, the only one writing about it.2

Will Pomerantz, VP of Special Projects for Virgin Galactic, said in response to my query that, “Mojave’s certainly full of rumors, so it’s good to have a chance to clarify. 

These are not rumors. They are accurate reports. They have been persistent and consistent for more than four years. My confidence in the sources and the accuracy of their information has only increased during that time.

On the basis of the great results from PF01 and PF02 [the first two powered flights], coupled with continued ground testing, we do expect the present hybrid motor to be capable of carrying passengers into space….” (Later Pomerantz confirmed that he was referring to a full complement of passengers and crew when using the hybrid motor.) 

This is an interesting statement. Note that he says they “expect” the present hybrid motor to reach space with a full load of passengers. I would think that after 9 years of development and with a flight into space now reportedly set for February, there would be a more definite statement that this on the status of the engine and its capabilities. (I’ll note the February spaceflight estimate came from Richard Branson, who’s consistently overly optimistic about such things.)

I would think that the engine would have been fully tested on the ground at full thrust and for full duration by now. And further, that Virgin Galactic would have released a video showing such a test and released details of it. My sources say the nitrous oxide-rubber hybrid has never had a full duration hot fire at full power. Further, they say the engine isn’t powerful enough to get the ship all the way to space.

As always, we’ll continue to look at a variety of ways to improve the motor’s performance and cost-effectiveness.”

Another rather vague statement. I’m not really sure what that means.

I can tell you what I have seen and heard here in Mojave over the past 10 months. My sources indicate that a number of alternate engines have been tested by Scaled Composites, Virgin Galactic and contractors. I have first-hand knowledge about the tests of three of these engines. I saw two of them personally, and viewed the aftermath of a third one a few hours after the engine blew itself apart on the test stand.

1.  On Dec. 5, 2012, George Whittinghill of Whittinghill Aerospace conducted a test of an alternative engine design at a test stand at the Mojave Air and Space Port.

The test was conducted after dusk. Due to the darkness and nature of the camera, the video is not very clear. The test actually went a lot better than it looks in the video. It’s hard to tell, but the actual hot fire lasted about 20 to 30 seconds.

2.  A second contractor — whose name I’m not sure of — tested a different engine on the same test stand on Jan. 23, 2013.

Jan2013_hybrid_hotfire

Hybrid engine test at the Mojave Air and Space Port on Jan. 23, 2013. (Credit: Douglas Messier)

That was a memorable test because the engine burned for maybe 30 seconds and then it wouldn’t shut off. It kept burning for quite a long time, sending a column of black smoke over the test stand and drifting southeast toward the spaceport. Emergency personnel could be heard discussing what to do over the radio; they decided not to approach the site until after the nitrous oxide in the tank burned itself out. It was the right call. The test crew was in no danger; they were safely inside a bunker, so there was no danger to them.

Jan2013_hybrid_hotfire_end

A hybrid engine continues to burn after its shutoff time. (Credit: Douglas Messier0

3. Scaled Composites destroyed a nitrous oxide/nylon engine during a hot fire at a different test site on May 17, 2013. The accident blew out the nozzle and engine casing; they ended up on the desert floor far from the test article. The test stand was wrecked. And a cloud of nitrous oxide appeared over the test area.

He added that while Scaled is not working on any liquid engines Virgin Galactic is, though only for the LauncherOne orbital rocket which will be released from the WhiteKnightTwo (WK2) aircraft.

That’s might well be true. My information about the work on liquid propulsion is far less clear. They do seem determined for the time being to get the hybrid to work.

The more interesting question is why. Replacing a hybrid engine after every flight is expensive. It’s time consuming. It prevents the spacecraft from being refueled, serviced and sent back into space quickly.

If Virgin Galactic is serious about flying frequently and reducing the highest ticket prices in this emerging industry (now up to $250,000 without having flown anyone yet), why is it not pursing a liquid-fuel replacement?

Notes

1.  The issue has been discussed in a number of previous posts, including:

2. I’m not sure why The Lurio Report failed to cite either me or Parabolic Arc as the source of these stories. The rest of the report — which covers a variety of other commercial space news — is meticulous about citing other sources. It’s odd, but frankly speaking, this is the least important aspect of the story — hence it being relegated to a footnote here. There is far more at stake than any hurt feelings.

  • Nickolai

    On the use of the word “expect”
    That sounds plenty confident to me. That’s more confidence than Elon expressed for F9 v1.1

    On not replacing the hybrid with a liquid on SS2:
    Maybe they’ve determined that for their immediate needs the drawbacks of a hybrid are not that big of a deal. As long as you have a serviceable design and a good process for switching out the solid fuel, I imagine you could get turnaround time pretty low, even in the single digits hours range. Switching to a liquid would probably require a pretty significant redesign of the tail end which would more than likely just delay them further.

    Still, this is confusing. Have they in fact tested it at full duration? If so, why not announce it? If not, why is Pomerantz saying this?

    Come February we’ll probably know more.

  • Douglas Messier

    My sources say they haven’t tested that engine to full duration. At the NewSpace Conference back in July, Mark Sirangelo of Sierra Nevada Corporation said they had done so, and said the engine was powerful enough to get the vehicle into space.

    It’s possible they could create a liquid engine that would not involve major changes to the vehicle.

  • Richard

    Don’t confuse he wording of VG and SpaceX. SpaceX use words like expect and probably to define things that are highly likely to happen in the next week. VG use words like definately and will to describe things that are now at 12years rather than the ‘will’ 4 years. A couple of months ago it was will be flying commercially into space by Christmas and now it’s possible they may get a test pilot on a non space powered 3rd flight by then.

  • Robert Gishubl

    Good summary, I have to agree that not having had a full power full duration test on the ground is a real concern to achieving comercial flights any time soon.
    At this rate of progress SpaceX will be flying paid passengers before Virgin Galactic.
    I do hope they get a full duration burn soon so they have some hope of getting paying passengers by Christmas 2014.
    I would expect multiple full duration burns on the ground before anyone takes it up in the air.

  • Lech

    I think that replacing entire hybrid engine between flights might be less time consuming then service of sophisticated liquid fuel engine. Additionally hybrids are safer.

  • DougSpace

    Thanks for your original reporting. You’re giving us some helpful insights which we wouldn’t have any other way.

  • therealdmt

    “I’m not sure why The Lurio Report failed to cite either me or Parabolic Arc as the source of these stories.”

    There are five possible reasons:

    1) The Lorio Report writer and/or editor is a classless scumbag

    2) The Lorio Report writer is a rank amateur, clueless of the etiquette involved

    3) The Lorio report writer is incompetent

    4) It was an honest mistake or oversight on the part of the writer

    5) The Lorio Report writer fears you

    Personally, I prefer to believe that it is reason 1. YMMV.

  • therealdmt

    Well, Mr. Sirangelo should know.

    If though they haven’t in fact tested it for full duration on the ground yet, that would be concerning to say the least. It would seem to imply that they’re afraid of problems occurring (perhaps catastrophic problems) in a full duration test. If so, I wouldn’t want to be one of those test pilots strapping in just in front of that motor!

    This could all be solved by a simple official statement by any of the involved parties (Sierra Nevada, Scaled Composites, or Virgin Galactic) that the engine has been successfully tested at full duration (preferably more than once, but…). Or, if it hasn’t, they could test it at full duration. Or, if they’re not prepared to do that yet, they could say that the engine, while quite far along, is still in the development process (obviously this last wouldn’t be ideal as it raises schedule concerns for an already overdue service).

  • therealdmt

    Another option if not wanting to seem to respond directly to rumors, would be to simply post video (perhaps without announcement) of long duration engine testing, such as SpaceX did with their new Merlin 1D engine as they were qualifying it.

  • DBC

    The failure of one of the most visible New Space companies isn’t exactly something we should be cheering for… Especially in a public forum like this.

    XCOR seems to be years behind Virgin – what do you think will happen to XCOR’s access to funding if Virgin fails? Answer: Nobody will care if they have a different motor or fundamentally different vehicle, funding sources will only know that Richard Branson lost a ton of money on reusable suborbital spacecraft and they most certainly will not want to “make the same mistake”.

  • Douglas Messier

    Charles Lurio is a good guy. I was a bit miffed over this ,but nothing more.

  • Hemingway

    Virgin Galactic is hiring a senior engineer whose primary role “involves taking a leadership role in the “clean sheet” development of new liquid-fueled rocket engines. Responsibilities will include conceptual through critical design of engine components, production, developmental and flight qualification testing, and flight test support.” Are they changing engine direction to liquid – fueled? http://www.linkedin.com/jobs2/view/7175665?trk=jobs_seeking_view_job&goback=.vjs_7017442_*2_*2_*2_false_*2_*2

  • Chris Courtois

    That fact that this hasn’t happened yet… like sometime LAST year… is very telling and goes to show these likely are not “rumors”!

  • Douglas Messier

    The assumption that hybrids are safer is questionable.

  • Nickolai

    No, they have been planning a liquid engine for LauncherOne for some time. See above:
    “He added that while Scaled is not working on any liquid engines Virgin Galactic is, though only for the LauncherOne orbital rocket which will be released from the WhiteKnightTwo (WK2) aircraft.”

  • Douglas Messier

    I think they’ll be flying under power again fairly soon. The last I heard was by the end of this month, but that may have slipped.

    Musk’s schedules tend to slip, but he usually delivers on his promise — if not always perfectly. Branson’s claims are bold and often not connected to reality. To their credit, the people actually running the company are much more cautious relating to schedules.

  • Nickolai

    If you get a chance, a good follow up would be to ask why they aren’t being more public about the full duration test. Maybe they have a good reason?

  • Douglas Messier

    I agree with the first paragraph. I take no pleasure in writing these stories. I want Virgin to succeed. It’s good for them, it’s good for the industry. I know some of the folks involved. They’re good people. I like them. It’s not fun to report on these things.

    You’re off base on XCOR. The Lynx is being built right now in the hangar. Components are coming in. The latest public estimate is first quarter 2014. That’s probably a year later than they had hoped. But, it is coming along. I can personally vouch for that. I can’t speak in detail about funding, but they’re in good shape there.

  • DBC

    Well hopefully it works perfectly the first time so they don’t end up like Virgin – still working out the kinks 2 years after the first (glide)flight test.

  • therealdmt

    I’m just having a little fun with it.

  • Richard

    GF01 was just over 3 years ago now and it’s taken 6 months to do 2 powered flights so judging on past performance I think it will be at least another 2 or 3 years before we see the “flights every day” commercial service. XCOR are being less ambitious with their plans so hopefully their development cycle will be quicker. They have a well tested engine solution so hopefully those problems will be quick for them, but the aerodynamics are wind tunnel only so far, so I would expect those to offer XCOR the most issues. Scaled have years of experience in those areas but there was still a long development and modification process there for SS2. Fundamentally they are both trying to do something that is extremely difficult and in both cases pioneering in their own way, getting into space doesn’t seem to be very simple or quick!

  • http://exoscientist.blogspot.com/ Robert Clark

    That’s good news on XCOR.

    Bob Clark

  • http://exoscientist.blogspot.com/ Robert Clark

    Another answer, it must be said, is that reporters like to give the impression that they are the ones breaking a story.

    Bob Clark

  • http://exoscientist.blogspot.com/ Robert Clark

    Good points. My guess is they haven’t done a full power test yet because on the short test burns they’ve seen some anomalies they don’t like.

    Bob Clark

  • ٩๏̯͡๏۶

    Who’s cheering? This is horrible.