Tuesday, June 30, 2009

The Space Cadets

Recently, NASA announced the selection of the 2009 Astronaut Candidate class. This is the 20th group selected since the first seven back in 1959, the first group selected since 2004, and at nine, one of the smallest groups ever. The composition of the group is ... interesting.

At a first glance, it looks like there are three pilots and six mission specialists in this group. There are three former test pilots, two flight surgeons, a biomedical scientist, a former ISS flight controller, and two people whose selection I find fascinating. One was a CIA intelligence analyst before being selected, the other was a special assistant to the Vice Chairman of the Joint Chiefs of Staff.

Really, why haven't we cross-trained an intel analyst as an astronaut before now? I'd never really thought about it before I saw this selection list, but the idea seems obvious now. Space operations are going to become more important in the future, not less; and we need for our leaders to get good, solid, reality-based advice on what's going on not only in the world but up above it. It'll be interesting to see if she hangs around long enough to get a flight assignment, and even more interesting to see if she goes back to the Agency afterwards.

Likewise, space operations are also becoming more and more important to the military. Cross-training a staff officer as an astronaut also makes good sense. There's a lot of unmanned space experience in the Pentagon already, but there's nothing like the perspective of a man who's been there.

It'll be interesting to see where this class ends up. They're going to be putting the Shuttle up on blocks by the time this group gets out of training, so it's an open question what they're going to ride on when the do get their first missions. But that's a story for another day.

Monday, June 22, 2009

Video Del Fuego, Part XXII

Words are unnecessary. This speaks for itself:

Wednesday, June 17, 2009

Holy Wiffleball, Batman!

They say when it rains, it pours. That sure seems to be the case this week. First, we have what looks like an incipient revolution in Iran. Now ... hold on to your hats, boys and girls, because it's looking like the future is about to arrive.

I'm talking about the "Wiffleball" series of prototype fusion reactors built by the late Robert Bussard's Polywell outfit. Classical Values has more of the scoop here.

Now, let's not read more into this than is actually being said. They aren't all the way there yet. There's still a full-scale unit to prove out. There are still a lot of technical details to get done right. But at the same time, let's realize what's actually happening, here.

First: The WB-7 prototype generated results sufficiently interesting for the Navy to spring for a larger and much more powerful device, WB-8. To me, this says that the data to date is solid enough that the Navy thinks this is a line worth pursuing.

Second: The Navy is asking for a conceptual design for a follow-on WB-9 device. This says that if WB-8 does work as advertised, they might want to hit the ground running for the next step.

Third (and perhaps most importantly): The Navy is asking for a WB-8.1 mod that will explore a different reaction than what has been looked at to date. Instead of a deuterium-deuterium fusion reaction, WB-8.1 will run on hydrogen and boron-11. That's key, because while the D-D reaction is easier to start, it spits out stray neutrons as part of the process. That's bad for several reasons. One, neutrons carry energy away that's damn near impossible to recover and use. And two, stray neutrons tend to make things radioactive. But some reactions, such as the one between hydrogen and boron-11, produce no stray neutrons. Not only is more of the energy recoverable and usable, but the reactor equipment and structure will not eventually become too radioactive to use safely.

Fourth: The Navy is asking Polywell to make its p-B11 rig compatible with all future WB prototypes. Well, we can see where this is going.

The obvious reading of the tea leaves here is that the Navy is looking for a replacement for its current generation of nuclear reactors. Makes good sense, really; nukes are damned expensive, aside from being moderately hazardous to run. If you can replace it with an electric gizmo that eats non-radioactive fuel and spits out electricity, that saves you plenty of money and grief over the life of a ship.

As a side benefit, we also get to use this technology dirt-side, to replace all manner of filth-producing power plants. Nuclear, gas, coal, no matter, they all produce something unpleasant as a side effect. This, on the other hand, produces helium. Just helium. Helium, far from being noxious or unpleasant, is occasionally useful. Besides which, abundant clean power changes things. Lots of things.

And as another side benefit ... well, if it works out, a 3-meter diameter reactor looks like it should have a power-to-weight ratio useful for driving a fully reusable surface-to-orbit rocket. And once you're in orbit, in terms of energy you're halfway to anywhere in the Solar System. Cheap, reliable access to space changes things. Lots of things.

I'll keep watching, fingers crossed and knocking on wood, but it sure looks like we're finally moving forward.

Tuesday, June 16, 2009

The Tree of Liberty ...

The Tree of Liberty must be refreshed from time to time with the blood of patriots and tyrants. It is its natural manure.
-- Thomas Jefferson

The people of Iran are presently making a down-payment on the price of Liberty. The cost is high, as we well know:

These are the times that try men's souls. The summer soldier and the sunshine patriot will, in this crisis, shrink from the service of their country; but he that stands it now deserves the love and thanks of man and woman. Tyranny, like hell, is not easily conquered; yet we have this consolation with us, that the harder the conflict, the more glorious the triumph. What we obtain too cheap we esteem too lightly: it is dearness only that gives every thing its value. Heaven knows how to put a proper price upon its goods; and it would be strange indeed if so celestial an article as FREEDOM should not be highly rated.
-- Thomas Paine

Stout hearts, brothers. Though the road be long and hard, rest assured that there does not exist a cause more worth the fighting for. All the world is watching, we're all pulling for you, and we know you can do this. Keep the pressure on, make the fence-sitters come down and dance, and force the Army to choose.

Win or lose, this is your day. Don't waste it.

Tuesday, June 09, 2009

What's in a Name?

There's quite a lot that goes on outside of my notice, especially if I've been busy with other matters, so I mostly missed the blog-scuffle surrounding the outing of Publius by one Ed Whelan. I wouldn't know either of them from Adam, to be honest. I only find the issue of interest because ... well, it brings back some memories. I've been on the 'Net in its various forms for quite a while now, and anon-pseudo-public question has always been there. You'll find proponents for each approach. And you'll find individuals for whom each approach is exactly right, and exactly wrong.

I got my start on the 'Net in 1992 or so with GEnie. Just about everyone had a handle. A handle was nothing more or less than the name you went by. For a while, I went by "Deacon Blues". But after about a year or so, I had an epiphany. I noticed something about the people online for whom I had the most respect. They were always courteous, helpful, good-natured ... and almost invariably, they went by their own names. I decided right then that I would do the same, and I've flown my flag proudly ever since.

It's a decidedly mixed blessing.

Nothing ever really dies on the 'Net. All of my Usenet escapades are still there, searchable all the way back to my first post, way way back when. So, if you roll this way, you really can't hide anything. If you Google my name, you'll eventually find it all ... plus at least two other guys, which really kind of surprised me. (It's not an especially common name...) Still, I knew that going in. I don't mind the accountability. It makes me think twice, so that I don't say anything that I'll profoundly regret later. I can take pride in the fact that, for the most part, I've written nothing I'd be ashamed to have my daughter stumble upon someday.

On the other hand ... Elsewhere here on Blogspot, you'll find my colleague Mr. X over at Chair Force Engineer. He speaks a lot more candidly about his industry -- maybe even his employer -- than I ever would, and probably has much to fear if his identity were compromised. I fully understand why he's adopted a pseudonym. Publius, a non-tenured professor of law, wanted to keep his professional identity distinct from his opinion writing. That's also a valid concern. And then there are people with legitimate concerns about attracting stalkers. There's no limit to the full-on crazy some people on the 'Net can muster. I can't complain about their choice.

On the other other hand ... Anonymity gives some people license to become the rude public nuisance that they always wanted to be, but never had the nerve. I can only think of a handful of "real" names that I can associate with genuinely unpleasant people I've encountered online. Most of the jerks, trolls, and oxygen thieves I've run into hereabouts have been cruising under fake names. They exist to derail discussions. They thrive on vandalism. You still see them on blog forums today, but let me tell you, their troll-fu is weak. The trolls of old could utterly destroy a newsgroup. There were two particularly bitter flame wars I remember, both about ten years ago, both instigated by anonymous trolls. In one case, the troll's primary victim was unusually diligent, and ended up cracking his real ID. Said troll vanished post-haste, and was missed by no one. But the damage had been done, and the quality of conversation never really recovered. The other one got really ugly. A complaint was filed with an ISP, which resulted in the guy losing his job. He stayed around, under his real name, but got in a second flame-war with -- get this -- another anonymous troll. That flame-war ended in a fist-fight one Saturday morning outside of the city limits. Yes, even with blog-trolls, the modern 'Net is an improvement. Usenet was an angry, angry place. I don't miss it.

Anyway, that brings me to another serious disadvantage of pseudonyms. People who disagree with you can become obsessed with finding out who you really are. They think it's like shaving Samson's hair, or giving Superman kryptonite underwear. They think that by outing you, they can get you to shut up. And sometimes they're right. That doesn't make it fair or honest, but occasionally, it's effective. Yet another reason I hoist my flag proudly: no secrets, no drama.

It's worked pretty well so far.

Tuesday, June 02, 2009

Air France 447

Very bad news Monday: Air France flight 447, an Airbus 330 enroute from Rio de Janeiro to Paris, went down in the Atlantic Ocean between South America and Africa. We may never know exactly what happened. The "black box" lies under 11,000 feet of water just east of the Mid-Atlantic Ridge, and will be very difficult indeed to locate, much less recover. But although the details may never be known, I think we have enough information to know the broad outlines of what happened.

Here is the sequence of events, such as we know them as of Tuesday evening:

1) 0133 UTC: Verbal contact with crew at waypoint INTOL.
2) 0210 UTC: First ACARS message, indicating disconnection of the autopilot.
3) ~0210 UTC: Second ACARS message, indicating mode transition of flight control system.
4) ~0212 UTC: Series of ACARS messages indicating failures of the air data computer and the standby instruments.
5) ~0212 UTC: Series of ACARS messages indicating failures of two of three flight control computers.
6) 0214 UTC: Last ACARS messages, indicating electrical system failure, and failure of cabin pressurization.

There's been a lot of discussion about lightning. I tend not to give it much credence. Modern jet aircraft are designed with the full knowledge not that it might get hit, but that it will get hit. They can take one hit, maybe more than one, and still recover full function. So, something else had to have happened.

Tim Vasquez, a former Air Force meteorologist, has a detailed analysis posted on his site. He overlays the flight path of AF447 onto a time-lapse of satellite weather data, which shows clearly that AF447 was flying over some pretty strong thunderstorms. One of the things in the time-lapse picture that pops out at you is a very strong updraft at 0200 UTC, just to the left of AF447's projected flight path.

Flying over thunderstorms is something commercial pilots do all the time, but none of them really enjoy doing it. Somewhere in the southwestern US, hanging over the base ops building, was a sign that read "There is no reason to fly through a thunderstorm in peacetime." Pilots are trained from day one to respect the authority of His Imperial Majesty, Cumulonimbus Rex. Modern storm-avoidance radars, standard equipment on passenger jets, make the job of avoiding dangerous conditions much easier. But still, things can -- and do -- sneak up on you. The weather radar doesn't have a 180-degree field of view. The specifics vary depending on model, but they can only "see" a cone out in front of the aircraft. Under most conditions, that gives a pilot plenty of warning. But, if a fast-developing updraft gets started right after your radar sweeps over it...

The sequence of the ACARS messages was the last piece in the puzzle. I may be wrong, but based on what I know, this is what I think happened.

The aircraft was upset by a very powerful updraft. We don't know exactly what attitude the aircraft was pushed into, but we do know that the autopilot kicked off. They're designed to do that automatically, if the angle of attack or the angle of sideslip get too high. Further, if the aircraft deviates far enough from nominal values for AOA and sideslip, the flight control computer will switch into an emergency mode, giving the pilot more control authority so that he can right the aircraft. Sometimes, that's enough. But the really nasty thing about unusual attitudes is that the data the air data computer relies on to feed the flight controls becomes corrupted. One by one, the flight control computers drop out as they encounter exceptions they weren't coded to handle. In an aircraft with fully fly-by-wire controls, this is fatal. Without a computer to translate his stick motion into control commands, the pilot cannot control the airplane. Inertia takes over. Inevitably, the stresses on the airframe become too great, the structure fails, and the airplane disintegrates.

If they can recover and analyze enough of the debris, that might tell a different tale. I hope they do, and they can. Maybe there's a clue in there that will tell us how to avoid the next accident. Or maybe not. One thing that strikes me sometimes as I drive past an airport and see airplanes sailing gracefully through the sky in exactly the way a hundred tons of aluminum shouldn't ... You've got to know, there's a risk in doing this. It's a small one. It's one we work hard to minimize.

But it'll never, never go away.

[Addendum, 10Jun09: Well, the danger of early speculation is that you end up getting details wrong. It's beginning to look like icing may have played a role. Ordinarily, the air up at that altitude is so cold that supercooled water cannot exist, and icing generally isn't a danger. But a sufficiently strong updraft might be able to haul enough moisture skyward to ice up some exposed surfaces ... such as the pitot tube.

[Airplanes have used pitot-static systems for years to measure airspeed and altitude. Indeed, until fairly recently, they were the only way to measure them. If your pitot tube ices over, you're essentially blind. But, they have heaters that can melt the ice off, provided that they've been turned on. Now here's where it gets interesting. Modern airplanes also have inertial navigation systems, that use a different method to compute speed. You no longer lose all of your information in an ice event ... but which set of information does your air data computer believe? And which set does it show the pilot? Is the pilot flying according to one airspeed, while the computer ciphers out the control laws in another? That can't possibly end well.

[The interesting thing here is that Airbus appears to have anticipated this particular corner, and has had a fix available since January. The upgrades had been propagating through the fleet with no particular urgency. I expect the urgency to step up a notch or two...

[I have to hand it to the engineers at Airbus, though. That was fast work, figuring out what might have gone wrong from fragments and scraps of error messages. It's in the finest traditions of our profession, and accelerated upgrades may well save lives in the future. Well done, gentlemen!]