Business, Space

Off To Mojave

16 Comments

Hoping to get up there and see SS2 in flight.

[Update mid-afternoon]

OK, I’m back. Got to the flight line a few minutes before the drop. I took some pictures, but I’m sure that Virgin’s are better. I’ll look at them and see if I have anything worth posting, but I didn’t have a lot of zoom on the camera.

On a related note, I stopped over at XCOR and fulfilled some of the last of my Kickstarter obligations, where it was gently pointed out to me that I’d deployed some sloppy wording in the section on Lynx, unintentionally implying that it doesn’t have engine-out capability at takeoff. I meant to say loss of thrust, not premature engine termination.

It’s quite annoying to me, given how much effort and time I spent to get it right. Most people won’t notice it, but to me it’s like a mountain, a VAST BOWL OF PUS. Now people will be saying, “Gee, what else did he screw up?”

So if you don’t hear from me after this, it will be because I went down the local SCA chapter to borrow a sword with which to ritually liberate my viscera.

[Update a few minutes later]

Here are a couple of nice shots, courtesy of Doug Messier.

16 thoughts on “Off To Mojave”

  1. Looks like they might step up the test flight tempo a bit. In the past they’ve tended to have large gaps in flights outside of the summer. For example, they had a gap between October and December 11 of last year, which was the last flight of SpaceShipTwo and its carrier plane. They had a three month gap in 2012-2013 between December and March and a four month gap between December and April in 2011-2012. The last flight in January was in early 2011.

    I hope you got to see the flight!

    1. If they don’t seriously increase their flight tempo, I don’t see how they’ll go operational this year or next. They need to get to the point where their test flights are so routine that they don’t make it on the news. If all went well on the last flight, they need to gradually increase the burn times (perhaps in 5 second increments) to expand the flight envelop. They need to develop crew proficiency, validate their systems’ reliability, and do all the things needed to begin commercial operations. I have no idea what their flight test plans are but it seems they’ll need dozens of powered flights at a minimum to cover everything. If their tempo doesn’t increase to at least one flight per week fairly soon, I don’t see how they’ll be operational this year.

      1. Actually, to first order, their launches no longer make it into the general news, unless they’re involved with NASA. I didn’t see much coverage of Monday’s flight.

    1. I wasn’t being ironic or sarcastic. It really was “gently.” You know, “more in sorrow than in anger.” It just drives me crazy that, no matter how many times I and my editor read that, we always read what I meant, instead of what I wrote. No matter how much you edit, something always sneaks through. I’m hoping that this was that thing. And when I say (as is standard) in acknowledgments that “any remaining errors are, of course, mine,” that’s exactly the kind of thing that I’m talking about.

    1. I see that quite noticeable hiccup in the exhaust flame just after ignition is still there. Not real confidence-inspiring, that.

  4. Actually, I am the one who “gently pointed out” the book’s error. I haven’t read the whole book yet (having just received it today) but the Lynx description has a significant error. The book reads: “If there is a premature engine shutdown, it would mean simply a mission failure, unless it occurred right after takeoff, in which case it could possibly kill or injure both aboard.” Lynx has 4 engines, and is designed to be able to sustain loss of three at any time, with the ability to dump LOX and return to the takeoff runway. Loss of 4 engines does have a zone of about 6 seconds within which you will be landing off-field with likely major airframe damage but not likely to lead to injuries. There is no commercial airliner that can do this.

    Hey, I’m gonna ride this thing and the pilot is a friend of mine. 🙂

    Dan DeLong
    Chief Engineer, XCOR Aerospace

    1. But given the reliability of piston pumps, as opposed to turbopumps that are usually running just short of flying apart, wouldn’t a simultaneous 4-engine failure go so against the odds that the crew could risk death or injury from shock at the unlikelihood of it. assuming there’s no daisy chain failure scenario? There’s also a reading where you could risk death or injury in an engine out situation by deciding to do something like a low-level inverted flyby of the tower with no hands.

      Just trying to give Rand the benefit of the doubt. ^_^

    1. When I was writing code to evaluate the temperature profile through a rolling combustion chamber liner, I found an error in the textbook’s formula for heat transfer. Perhaps I’m actually the first person to try and code their parameterized transient heat-transfer equations because students generally aren’t that motivated. Then I had my own error finding all the roots to x=x*ln(x) for the underlying Fourier series, so I guess it all worked out.

      1. When I was a research assistant, and later a researcher, with a small academic software maintenance group, we used to regularly get people sending us emails asking how the heck you implement a particular part of our supervisor’s PhD thesis. We kindly directed each one to the errata page on her website, and later to the errata section of the pdf she made available. I don’t know if that’s common, but when I started work at my current employer I immediately took a look through the code and found a copy of my prior notice to them, embedded in the comments.

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