--FIRST -PREV NEXT-
"Fondly do we hope, fervently do we pray, that this mighty scourge of war will speedily pass away. Yet, if God wills that it continue until all the wealth piled by the bondsman's two hundred and fifty years of unrequited toil shall be sunk, and until every drop of blood drawn with the lash shall be paid by another drawn with the sword, as was said three thousand years ago, so still it must be said, 'the judgements of the Lord are true and righteous altogether.'
"With malice for none, with charity for all, with firmness in the right as God gives us to see the right, let us strive on to finish the work we are in, to bind up the nation's wounds, to care for him who shall have borne the battle and for his widow and his orphan, to do all which may achieve and cherish a just and lasting peace among ourselves and with all nations."
-- President Abraham Lincoln, March 4th, 1865
By his second Inauguration, Lincoln was at long last able to begin thinking about after. Grant had Lee bottled up in Petersburg and Richmond. Sherman was marching at will in the Carolinas with no effective opposition. Sure, Joseph E. Johnston led a force shadowing Sherman, but while it was a force that marched with good order and discipline, its military capability was more theoretical than actual. Johnston had actually said as much in a letter to Lee after the Battle of Bentonville -- "I can do no more than annoy him."
The Confederacy was falling apart.
Its legislature had already essentially given up. On the 18th of March, the Confederate Congress adjourned sine die -- meaning, the Speaker adjourned without specifying a date they would reconvene. The dread secret no one dared breathe, but that everyone nevertheless knew, was that there would never be another session. Most of the Confederacy's civilian leadership was taking the opportunity the get gone while they still could.
Its army had, and hadn't, given up. Lee should have had about ninety thousand men to resist Grant's hundred-fifty-thousand. Should have, except that about two-thirds of them had deserted. This left Lee with thirty thousand men to hold just over fifty miles of line. An assault at three-to-two odds is a bloodbath for the attacker. An assault at five-to-one ... not so much.
By mid-March, Lee had one chance and one chance only. He knew that Sheridan was on his way from the Shenandoah with fifty thousand men, and Sherman was marching north from the Carolinas with sixty thousand more. If he waited too long, Grant would have well over two hundred thousand men at his command, while he would never have any more men than he currently had. If he was going to stage a breakout, it would have to be now.
Initially, the battle at Fort Steadman went well for the Confederacy. The forces under Confederate General John B. Gordon captured the Union works, and began directing enfilading fire on the Union trenches. But the Union counterattack was swift, sure, and effective ... so much so that Grant, who was a few miles away conferring with Lincoln, didn't know about the affair until it was all over. There were so many Union troops essentially sitting around doing nothing that it was a trivial matter to concentrate enough force to drive the assault back.
While that wasn't the final blow, it was very close to it. The Confederate army couldn't hold out much longer. When the end came at Petersburg, it came quickly.
The Battle of Five Forks would come a few days later, on the first of April. It was here that the Union finally turned the Confederate flank, and the Confederates simply did not have the manpower to stretch their line any more. The line caved, in several places. The position was no longer tenable, so Lee ordered a general retreat. He would try to lead his army west and south, along the Appomattox River, towards what he hoped would be a refuge, where he could find supplies for his men and a place to regroup.
Jefferson Davis, meanwhile, had entered a truly delusional state:
"Relieved from the necessity of guarding cities ... with an army free to move from point to point ... nothing is now needed to render our triumph certain but the exhibition of our own unquenchable resolve."
"Nothing is now needed" ... with the possible exceptions of food, munitions, and soldiers; all of which are conspicuously lacking at this point in the affair. I marvel at this passage. Davis cannot possibly have believed this drivel. And yet he committed it to paper as an exhortation to the people of the Confederacy ... at least, what was left of it. But on the other other hand, Davis wasn't a man known for lying ... leaving us with the inescapable conclusion that yes, he really did believe this bit of raving lunacy, meaning that yes, he has taken leave of his senses. Or equally possibly, his reputation for military acumen wasn't all that well-deserved after all.
A West Point man he was, but evidently, he slept through all of the lectures on logistics.
Lee hadn't. Which is why he was moving his army with all due speed to where he could resupply, with Grant and Sheridan dogging his steps the whole way ...
... one last roll of the dice.
Saturday, March 28, 2015
Monday, February 23, 2015
What Could Have Been
Way back in the earliest days of the Apollo Program, they had no clue how to do the job they'd been handed. When President Kennedy laid down the gauntlet to put a man on the Moon by the end of the decade, America had a grand total of fifteen minutes and twenty-two seconds of spaceflight experience, and didn't even have a man-rated orbital rocket yet.
The most obvious, and in some ways the technically safest approach would be to build a ginormous rocket and lift the whole thing -- lander, earth-return stage, and capsule -- all in one heave. They called that approach Direct Ascent.
In the end, they decided against that approach. As it happened, if you split the earth-return capsule totally apart from the lander, you could save weight on both. That means you don't need such an enormous rocket, and the overall project cost is lower.
And besides which ... the Direct Ascent version of the Apollo 13 scenario is grim. No separate LM spacecraft means no lifeboat, and no lifeboat means three dead astronauts.
But we can still imagine what might have been. Seferino Rengel has used the Orbiter space simulator to visualize what it would have looked like.
Looks great ... but, on the whole, it's just as well we didn't go this route.
The great thing about Orbiter is that you can take a walking tour of designs that never were. You can appreciate the aesthetics, and sometimes come to a realization about why we didn't take that branch. Direct Ascent was just one example. Another example is the Lockheed Star Clipper. The pilot in me looks at that beautiful lifting body and drools ... but the engineer looks at that fuel tank layout and screams "Foam strikes ahoy!"
Another great thing about Orbiter is that we can imagine things that we could be doing, but for whatever reason aren't. Take the Grand Tour, for instance. When I was young, I assumed that this was a once-in-a-lifetime thing, that you'd never see such a fortuitous alignment again. Not so fast! For Jupiter and Saturn, at least, that alignment repeats every so often, and you can get one of Uranus or Neptune into the act as well. Such an alignment is available ... oh, right about now. Had we been more alert on the trigger, we could have something like Eris Explorer on deck and ready to go.
The mission plan is breathtaking in its vision, and optimism. The Eris encounter would be in 2051. I'll be 84 years old, making the bold and possibly unwarranted assumption that I last that long. When we go -- and we will, I'm sure of it -- the senior scientists and engineers on the project will simply have to accept that they won't survive to see the project come to fruition. They will have to hand it off to a new generation to bring it all together at the target. They'll have to assume that the organizations will still be viable entities throughout the entire duration of the mission. That the sponsor governments will stay the course, and provide funding for the whole course.
I find such optimism encouraging. When we plant a field that our sons and daughters will harvest, we make an investment in their future. And we can't invest in a future that we don't believe in.
National Engineers Week is February 22nd through the 28th. If you can read this, thank a teacher. If you can read this in English, thank a veteran. But if you can read this on a computer, thank an engineer.
The most obvious, and in some ways the technically safest approach would be to build a ginormous rocket and lift the whole thing -- lander, earth-return stage, and capsule -- all in one heave. They called that approach Direct Ascent.
In the end, they decided against that approach. As it happened, if you split the earth-return capsule totally apart from the lander, you could save weight on both. That means you don't need such an enormous rocket, and the overall project cost is lower.
And besides which ... the Direct Ascent version of the Apollo 13 scenario is grim. No separate LM spacecraft means no lifeboat, and no lifeboat means three dead astronauts.
But we can still imagine what might have been. Seferino Rengel has used the Orbiter space simulator to visualize what it would have looked like.
Looks great ... but, on the whole, it's just as well we didn't go this route.
The great thing about Orbiter is that you can take a walking tour of designs that never were. You can appreciate the aesthetics, and sometimes come to a realization about why we didn't take that branch. Direct Ascent was just one example. Another example is the Lockheed Star Clipper. The pilot in me looks at that beautiful lifting body and drools ... but the engineer looks at that fuel tank layout and screams "Foam strikes ahoy!"
Another great thing about Orbiter is that we can imagine things that we could be doing, but for whatever reason aren't. Take the Grand Tour, for instance. When I was young, I assumed that this was a once-in-a-lifetime thing, that you'd never see such a fortuitous alignment again. Not so fast! For Jupiter and Saturn, at least, that alignment repeats every so often, and you can get one of Uranus or Neptune into the act as well. Such an alignment is available ... oh, right about now. Had we been more alert on the trigger, we could have something like Eris Explorer on deck and ready to go.
The mission plan is breathtaking in its vision, and optimism. The Eris encounter would be in 2051. I'll be 84 years old, making the bold and possibly unwarranted assumption that I last that long. When we go -- and we will, I'm sure of it -- the senior scientists and engineers on the project will simply have to accept that they won't survive to see the project come to fruition. They will have to hand it off to a new generation to bring it all together at the target. They'll have to assume that the organizations will still be viable entities throughout the entire duration of the mission. That the sponsor governments will stay the course, and provide funding for the whole course.
I find such optimism encouraging. When we plant a field that our sons and daughters will harvest, we make an investment in their future. And we can't invest in a future that we don't believe in.
National Engineers Week is February 22nd through the 28th. If you can read this, thank a teacher. If you can read this in English, thank a veteran. But if you can read this on a computer, thank an engineer.
Friday, February 13, 2015
Sesquicentennial, Part XLIII: Looking Ahead, Looking Back
--FIRST -PREV NEXT-
One hundred years ago, the Western Front had settled down into an awful stalemate. A system of trenches stretched from the Swiss border to the North Sea, and the land in between the trenches had been turned into a churn of mud by the combined efforts of German, Austrian, French, and British artillery. The men in those trenches probably thought to themselves that surely, no such vision of Hell had been brought to Earth before.
Except that, if any of them had thought to cast their sight back fifty years in time and two thousand miles to the west, they'd see quite clearly that it had.
The Siege of Petersburg was, in many ways, a preview of coming attractions.
Trenches? Check. Massive artillery pounding the Hell out of everything in sight? Check. Crazy plans to dig mines under the enemy works and pack them with explosives? Good God yes, check. People had every right to feel despair, disgust, dread, or any number of other emotions regarding what the Western Front had become ... but they had no right at all to feel surprised. The Western Front was really nothing more than Petersburg scaled up to fit a continent.
Granted, the Western Front nightmare lasted a good bit longer. But that's partly because Douglas Haig wasn't fit to stand in the company of either Grant or Sherman.
True, Lee was keeping Grant's army out of both Petersburg and Richmond. He was also pinned down there, unable to do anything but hold those two cities. He was also unable to keep Grant from extending his lines around Petersburg to the south, and Richmond to the north.
That was eventually going to be a problem.
You see, there was more to Sherman's plan than simple bloody-minded violence. Part of that can be seen by a modification to a map of Confederate railroads (the original can be found here).
Sherman's approximate line of march since jumping off in Spring 1864 is shown in orange. By mid-February, Sherman had reached the city of Columbia in South Carolina. That encounter ... went poorly for Columbia. Sherman claimed that he didn't order Columbia burnt to the ground ... but he wasn't exactly sorry it happened, either. That's neither here nor there, though; the main point I want to make is that he was exacting the maximum amount of damage possible against the Confederacy's ability to move supplies from where they were to where they weren't. Where they were tended to be the farms where food was grown and the shops where goods were made, and where they weren't was the Army of Northern Virginia.
Lee had exactly one life-line left open. And that was the rail line from Richmond to Danville. This had been recently connected to Greensboro in North Carolina, so in theory Lee could draw on supplies from points south ... except that due to Sherman's efforts, there wasn't much further south from which to draw.
This is more or less the point in a chess match at which you'd resign.
You resign in a chess match when you see the inevitable outcome, and know that no matter what move you make, even if you make the best move possible from your current position, you will lose. Your opponent will put your King in checkmate, and there's nothing you can do about it.
But Jefferson Davis was at least in nominal control, and he wasn't in a resigning mood. Was this stubborn pride, delusional lunacy, or some mix of the two? Because Davis had to have known the jig was well and truly up. Had to. He was a West Point man himself, and had enough military experience out on the sharp end to know what's what. But pride ... his pride would not allow him to admit he'd been beaten. Nor would it allow him to breathe a word of defeatism to another living soul.
No, surrender wasn't a word in Davis' vocabulary. So long as it was up to him, he'd grind it out to the last desperate inch.
And so it would go.
One hundred years ago, the Western Front had settled down into an awful stalemate. A system of trenches stretched from the Swiss border to the North Sea, and the land in between the trenches had been turned into a churn of mud by the combined efforts of German, Austrian, French, and British artillery. The men in those trenches probably thought to themselves that surely, no such vision of Hell had been brought to Earth before.
Except that, if any of them had thought to cast their sight back fifty years in time and two thousand miles to the west, they'd see quite clearly that it had.
The Siege of Petersburg was, in many ways, a preview of coming attractions.
Trenches? Check. Massive artillery pounding the Hell out of everything in sight? Check. Crazy plans to dig mines under the enemy works and pack them with explosives? Good God yes, check. People had every right to feel despair, disgust, dread, or any number of other emotions regarding what the Western Front had become ... but they had no right at all to feel surprised. The Western Front was really nothing more than Petersburg scaled up to fit a continent.
Granted, the Western Front nightmare lasted a good bit longer. But that's partly because Douglas Haig wasn't fit to stand in the company of either Grant or Sherman.
True, Lee was keeping Grant's army out of both Petersburg and Richmond. He was also pinned down there, unable to do anything but hold those two cities. He was also unable to keep Grant from extending his lines around Petersburg to the south, and Richmond to the north.
That was eventually going to be a problem.
You see, there was more to Sherman's plan than simple bloody-minded violence. Part of that can be seen by a modification to a map of Confederate railroads (the original can be found here).
Sherman's approximate line of march since jumping off in Spring 1864 is shown in orange. By mid-February, Sherman had reached the city of Columbia in South Carolina. That encounter ... went poorly for Columbia. Sherman claimed that he didn't order Columbia burnt to the ground ... but he wasn't exactly sorry it happened, either. That's neither here nor there, though; the main point I want to make is that he was exacting the maximum amount of damage possible against the Confederacy's ability to move supplies from where they were to where they weren't. Where they were tended to be the farms where food was grown and the shops where goods were made, and where they weren't was the Army of Northern Virginia.
Lee had exactly one life-line left open. And that was the rail line from Richmond to Danville. This had been recently connected to Greensboro in North Carolina, so in theory Lee could draw on supplies from points south ... except that due to Sherman's efforts, there wasn't much further south from which to draw.
This is more or less the point in a chess match at which you'd resign.
You resign in a chess match when you see the inevitable outcome, and know that no matter what move you make, even if you make the best move possible from your current position, you will lose. Your opponent will put your King in checkmate, and there's nothing you can do about it.
But Jefferson Davis was at least in nominal control, and he wasn't in a resigning mood. Was this stubborn pride, delusional lunacy, or some mix of the two? Because Davis had to have known the jig was well and truly up. Had to. He was a West Point man himself, and had enough military experience out on the sharp end to know what's what. But pride ... his pride would not allow him to admit he'd been beaten. Nor would it allow him to breathe a word of defeatism to another living soul.
No, surrender wasn't a word in Davis' vocabulary. So long as it was up to him, he'd grind it out to the last desperate inch.
And so it would go.
Tuesday, January 27, 2015
In Memoriam
High Flight
(Pilot Officer Gillespie Magee, No. 412 Squadron RCAF, KIA 12/11/1941)
Oh! I have slipped the surly bonds of earth
And danced the skies on laughter-silvered wings;
Sunward I've climbed, and joined the tumbling mirth
Of sun-split clouds - and done a hundred things
You have not dreamed of - wheeled and soared and swung
High in the sunlit silence. Hov'ring there
I've chased the shouting wind along, and flung
My eager craft through footless halls of air.
Up, up the long delirious, burning blue,
I've topped the windswept heights with easy grace
Where never lark, or even eagle flew -
And, while with silent lifting mind I've trod
The high untresspassed sanctity of space,
Put out my hand and touched the face of God.
In respectful memory of:
Virgil I. "Gus" Grissom, Edward H. White II, Roger Chaffee: Apollo 1, 1/27/1967
Vladimir Komarov: Soyuz 1, 4/23/1967
Major Michael J. Adams, USAF: X-15 Flight #191, 11/15/1967
Georgi Dobrovolsky, Vladislav Volkov, Viktor Patsayev: Soyuz 11/Salyut 1, 6/30/1971
Dick Scobee, Michael Smith, Ellison Onizuka, Judy Resnik, Ron McNair, Christa McAuliffe, Gregory Jarvis: Challenger, 1/28/1986
Rick Husband, William McCool, Dave Brown, Kalpana Chawla, Michael Anderson, Laurel Clark, Ilan Ramon: Columbia, 2/1/2003
Michael Alsbury, VSS Enterprise Flight PF04, 10/31/2014
Requiem aeternam donum est, Domine, et lux perpetua luceat eis.
(Pilot Officer Gillespie Magee, No. 412 Squadron RCAF, KIA 12/11/1941)
Oh! I have slipped the surly bonds of earth
And danced the skies on laughter-silvered wings;
Sunward I've climbed, and joined the tumbling mirth
Of sun-split clouds - and done a hundred things
You have not dreamed of - wheeled and soared and swung
High in the sunlit silence. Hov'ring there
I've chased the shouting wind along, and flung
My eager craft through footless halls of air.
Up, up the long delirious, burning blue,
I've topped the windswept heights with easy grace
Where never lark, or even eagle flew -
And, while with silent lifting mind I've trod
The high untresspassed sanctity of space,
Put out my hand and touched the face of God.
In respectful memory of:
Virgil I. "Gus" Grissom, Edward H. White II, Roger Chaffee: Apollo 1, 1/27/1967
Vladimir Komarov: Soyuz 1, 4/23/1967
Major Michael J. Adams, USAF: X-15 Flight #191, 11/15/1967
Georgi Dobrovolsky, Vladislav Volkov, Viktor Patsayev: Soyuz 11/Salyut 1, 6/30/1971
Dick Scobee, Michael Smith, Ellison Onizuka, Judy Resnik, Ron McNair, Christa McAuliffe, Gregory Jarvis: Challenger, 1/28/1986
Rick Husband, William McCool, Dave Brown, Kalpana Chawla, Michael Anderson, Laurel Clark, Ilan Ramon: Columbia, 2/1/2003
Michael Alsbury, VSS Enterprise Flight PF04, 10/31/2014
Requiem aeternam donum est, Domine, et lux perpetua luceat eis.
Saturday, January 17, 2015
Stopping The Earth
The short answer: It can't be done. Not no way, not no how. But first, some background...
I saw this item on Andrew Sullivan's site, a link to an article by Aatish Bhatia about what would happen if the Earth were to somehow stop orbiting around the Sun. Well, the obvious answer is that if it stopped orbiting, it's fall into the Sun. What Bhatia tells us, though, is specifically what would happen, on a day-to-day basis, during the sixty-four and a half days it'd take to get there.
I had no beef with that ... except for one sentence, early on in the article:
"What would happen to us if a giant space finger were to gently stop the Earth in its orbit?"
It didn't hit me right away. It set off a kind of slow-burn ... I don't want to call it annoyance, it doesn't rise to that level, but there's no other word that quite describes the sensation. Something was just not right with that sentence.
Gently.
Gently?
Before I reacted any further, I needed figures. What was Earth's mass, and its orbital speed? That will tell us the magnitude of kinetic energy we're talking about. And, once the numbers are crunched, we're talking about 2.685 x 10^33 Joules.
That's a totally nonsensical number. Once numbers get sufficiently large, they cease to have any real meaning. I can't relate that immensity to anything within my, or anyone else's experience. So, we go to find something else sufficiently gigantic that we might be able to use as a yardstick. For this purpose the Sun's total power output might serve. The Sun's power output is, on average, 3.846 x 10^26 Watts.
OK, that's another stupidly big number. But we can divide energy by power to get time. Which is ... 80.8 days.
And, friends, when you collect the Sun's entire power output for eighty freaking days, there is NO WAY to apply that much energy gently. That's like using a atom bomb to gently crack an egg. Or using a 120mm smoothbore tank gun to gently drive a finishing nail. It just ... no. You can't get there from here.
The same thing applies to stopping the Earth's rotation around its axis, which appears to be another popular Google search. People really seem to be afraid that this is a real thing ... which they shouldn't. Stopping the Earth from spinning isn't near as hard as stopping it in its tracks, but it's still so damn hard that it'll take totally stupid amounts of energy to do it. The Earth's rotational energy is 2.138 x 10^29 Joules ... yet again another ridiculously huge number. But we can divide that by the Sun's power output to get an idea of how it relates. It works out to 9 hours, 16 seconds.
And again, the after-effects of such stoppage become irrelevant. The friction of so much energy applied all at once would melt the crust to magma. (Which goes back to the point that there's no way to apply such a stupendous amount of energy gently.) What comes after is kind of beside the point. The rock under your feet suddenly becoming liquid is a much more immediate problem than anything that might happen afterwards.
Besides, no one's ever going to have that much energy all in one place to begin with. You can rest easy now, and stop worrying about this ever happening.
Now, all this reminds me of one of my favorite cheesy '70s sci-fi series ... Space: 1999. The premise, if you'll recall, was that the Moon got blasted out of Earth's orbit.
So, we'll need some numbers. First, the Moon's mass: 7.348 x 10^22 kilograms. And its orbital speed: 1.022 kilometers per second. The escape velocity at that distance is 1.414 times the orbital velocity, so the escape velocity is 1.445 km/sec. Now, we can compute the kinetic energy before and after the event, and see how much additional energy is required. That works out to be 3.834 x 10^28 Joules. Again, an unbelievably stupendous meaningless number. But we link it back to the Sun's power output, and we get about a minute and a half.
Yeah. No way in Hell is a nuclear waste dump generating that kind of kaboom.
Not that I care. That show is still one of my guilty pleasures.
I saw this item on Andrew Sullivan's site, a link to an article by Aatish Bhatia about what would happen if the Earth were to somehow stop orbiting around the Sun. Well, the obvious answer is that if it stopped orbiting, it's fall into the Sun. What Bhatia tells us, though, is specifically what would happen, on a day-to-day basis, during the sixty-four and a half days it'd take to get there.
I had no beef with that ... except for one sentence, early on in the article:
"What would happen to us if a giant space finger were to gently stop the Earth in its orbit?"
It didn't hit me right away. It set off a kind of slow-burn ... I don't want to call it annoyance, it doesn't rise to that level, but there's no other word that quite describes the sensation. Something was just not right with that sentence.
Gently.
Gently?
Before I reacted any further, I needed figures. What was Earth's mass, and its orbital speed? That will tell us the magnitude of kinetic energy we're talking about. And, once the numbers are crunched, we're talking about 2.685 x 10^33 Joules.
That's a totally nonsensical number. Once numbers get sufficiently large, they cease to have any real meaning. I can't relate that immensity to anything within my, or anyone else's experience. So, we go to find something else sufficiently gigantic that we might be able to use as a yardstick. For this purpose the Sun's total power output might serve. The Sun's power output is, on average, 3.846 x 10^26 Watts.
OK, that's another stupidly big number. But we can divide energy by power to get time. Which is ... 80.8 days.
And, friends, when you collect the Sun's entire power output for eighty freaking days, there is NO WAY to apply that much energy gently. That's like using a atom bomb to gently crack an egg. Or using a 120mm smoothbore tank gun to gently drive a finishing nail. It just ... no. You can't get there from here.
The same thing applies to stopping the Earth's rotation around its axis, which appears to be another popular Google search. People really seem to be afraid that this is a real thing ... which they shouldn't. Stopping the Earth from spinning isn't near as hard as stopping it in its tracks, but it's still so damn hard that it'll take totally stupid amounts of energy to do it. The Earth's rotational energy is 2.138 x 10^29 Joules ... yet again another ridiculously huge number. But we can divide that by the Sun's power output to get an idea of how it relates. It works out to 9 hours, 16 seconds.
And again, the after-effects of such stoppage become irrelevant. The friction of so much energy applied all at once would melt the crust to magma. (Which goes back to the point that there's no way to apply such a stupendous amount of energy gently.) What comes after is kind of beside the point. The rock under your feet suddenly becoming liquid is a much more immediate problem than anything that might happen afterwards.
Besides, no one's ever going to have that much energy all in one place to begin with. You can rest easy now, and stop worrying about this ever happening.
Now, all this reminds me of one of my favorite cheesy '70s sci-fi series ... Space: 1999. The premise, if you'll recall, was that the Moon got blasted out of Earth's orbit.
It was a different time.
So, we'll need some numbers. First, the Moon's mass: 7.348 x 10^22 kilograms. And its orbital speed: 1.022 kilometers per second. The escape velocity at that distance is 1.414 times the orbital velocity, so the escape velocity is 1.445 km/sec. Now, we can compute the kinetic energy before and after the event, and see how much additional energy is required. That works out to be 3.834 x 10^28 Joules. Again, an unbelievably stupendous meaningless number. But we link it back to the Sun's power output, and we get about a minute and a half.
Yeah. No way in Hell is a nuclear waste dump generating that kind of kaboom.
Not that I care. That show is still one of my guilty pleasures.
Monday, January 05, 2015
Fifteen for '15
It's one of those funny things that you really can't seem to quantify or prove, but nevertheless that everyone seems to agree upon: the older you get, the shorter a year gets. No one knows why. But everyone I've ever talked to about it agrees that it's so.
Anyway -- here we are, again. Another new year. Another old one gone to the discard pile. Except that it doesn't really feel all that new. That's something else that happens as you get older. I remember there used to be a magical feeling about approaching midnight on New Year's Eve. Like there was something special about the numbers rolling over to zero. That vanished for me somewhere between thirty-five and forty-five, not entirely sure where.
Having a teenager might have had something to do with it. That'll drive you to cynicism, alcoholism, or (often) both.
But I'm here to tell you, it gets better. They do grow up. They even -- Deo Gratia -- become rational adults.
And so, without further ado, fifteen observations for 2015.
ONE -- I'm going to be doubting the wisdom of this motif come 2020 or thereabouts. Maybe even sooner.
TWO -- Henceforth, I will be referring to Kim Jong-Un as The Great Hambino. When his government stops acting like a hobo on crank, he can have his name back.
THREE -- Big year ahead in spaceflight. For me, the highlight will probably be New Horizon's Pluto/Charon encounter in July. They've woken the ship up from the eight-year hibernation it's been in since the Jupiter fly-by in 2007, and the team is getting ready to begin its science mission in February. This is an encounter that means a lot for those of us who grew up when Pluto was the ninth planet, and to date the only one we haven't seen close up. That ends in July.
FOUR -- But wait, there's more! Dawn will be entering orbit around the dwarf planet Ceres in March, having left Vesta in September of 2012. Despite having been launched a year later than New Horizons, Dawn will end up being the first spacecraft to have a close encounter with a dwarf planet. On the other hand, Ceres may not be as interesting as Pluto ... but then again, it might. We don't know ahead of time what we'll find, which is part of what makes the trip worthwhile.
FIVE -- While the Dragon 2.0 won't fly this year, tomorrow morning we'll get to find out if they can land a Falcon first stage on an autonomous ocean barge or not. SpaceX is saying they have a 50-50 shot of this thing working right the first time. But I sure wouldn't put money on them not being able to figure it out within a flight or two. Once they work the bugs out, this will allow SpaceX to recover, refurbish, and re-use an enormous chunk of flight hardware that everyone else just throws away. Good news for SpaceX, as well as its shareholders and customers; mildly worrisome for everyone else in the business.
SIX -- It will be a while before anything is known for sure, but my guess is that Scaled Composites will identify what went wrong with VSS Enterprise, fix it, and be ready to go back into test by the end of the year. But that depends on a number of things -- the final NTSB report and whether or not Richard Branson wants to press ahead being the two most important ones.
SEVEN -- And last but not least, the planet-hunter Kepler isn't down for the count, after all. They've managed to work out a mode of operation that will allow some observations to go forward, even with its reduced capability. It may be several years before my #4 observation from last year comes to fruition -- that'll probably require much more capable sensors than we currently have -- but I'm still optimistic we'll find a habitable world Out There fairly soon.
EIGHT -- Nothing new to report on the fusion energy front ... yet. But keep an eye on this. The fact that a company as big as Lockheed has laid its name and reputation on the line tells me that they've got a solid path forward. The odds are that we won't hear anything new until it's demonstration time. This points back to items #5 through #7 from last year, and I'll say it again: while concern is warranted about our power future, panic isn't. More and more, it's looking like we'll have the tools we need when we need them.
NINE -- This is a partial call-back to #5 above ... but I just wanted to point out how far 3-D printing has come. The thrusters they're going to use both for contingency aborts and precision landings? Made by 3-D printing, with metal. Not plastic, metal. Also, a 3-D printer has been delivered to the International Space Station. I wasn't aware that was even possible. Early 3-D printing technology required gravity in order to do its thing. Apparently, they've figured out a way around that. Interestingly enough, the first thing they made with their new 3-D printer was a part for the printer ... which tells me we're that much closer to being able to build a machine that can rebuild itself. Cool, and scary, all at the same time.
TEN -- Please, merciful God, spare us Clinton vs. Bush in 2016. Surely there are other candidates. But I fear that may be how the primaries shake out.
ELEVEN -- What a difference a year makes. Several years of 8-8 futility, and all of a sudden the Cowboys turn into an unstoppable-on-the-road juggernaut. Which sets up an interesting situation this coming Sunday in Green Bay -- the irresistible force meets the immovable object. The Cowboys are undefeated on the road. The Packers are undefeated at home. One of those streaks ends on Sunday.
TWELVE -- Somewhat related: is anyone out there still questioning the wisdom of drafting Zack Martin instead of Johnny Manziel? Anyone? Anyone? Bueller?
THIRTEEN -- While the lower gas prices are nice, something's going on behind the scenes that no one's quite figured out yet. We know that Saudi Arabia spun their taps wide open, what we don't know is why. There are a few possibilities, ranging from the highly likely to the improbable. Increasing the supply drops the price, that's obvious. Question is, who benefits? And who's hurt? Is this intended to put some hurt on the Iranians? Maybe, and a weakened Iran would be a good thing for the Saudis. Do they want to put a squeeze on the Russians? Maybe, insofar as they've provided Iran with backing. Do they want to drive prices low enough to put the resurgent American oil industry in a bind? I tend to think that's an unintended consequence, but I'm just guessing. Low prices put advanced recovery techniques, such as fracking and tar sands, at an unfavorable place on the price curve. But if they see that as such a threat, then ... maybe they're drawing down low enough that it's "smoke 'em while you got 'em" time. But if their reserves were getting that low, the smart play would be to lean it out as long as possible, wouldn't it? In any case, this bears close attention, and you should probably keep an eye on it.
FOURTEEN -- When Autocorrect gets good enough to make this site obsolete, then it's time to worry about Artificial Intelligence.
FIFTEEN -- (Added 11Jan15) Yep. Definitely regretting this motif.
Anyway -- here we are, again. Another new year. Another old one gone to the discard pile. Except that it doesn't really feel all that new. That's something else that happens as you get older. I remember there used to be a magical feeling about approaching midnight on New Year's Eve. Like there was something special about the numbers rolling over to zero. That vanished for me somewhere between thirty-five and forty-five, not entirely sure where.
Having a teenager might have had something to do with it. That'll drive you to cynicism, alcoholism, or (often) both.
But I'm here to tell you, it gets better. They do grow up. They even -- Deo Gratia -- become rational adults.
And so, without further ado, fifteen observations for 2015.
ONE -- I'm going to be doubting the wisdom of this motif come 2020 or thereabouts. Maybe even sooner.
TWO -- Henceforth, I will be referring to Kim Jong-Un as The Great Hambino. When his government stops acting like a hobo on crank, he can have his name back.
THREE -- Big year ahead in spaceflight. For me, the highlight will probably be New Horizon's Pluto/Charon encounter in July. They've woken the ship up from the eight-year hibernation it's been in since the Jupiter fly-by in 2007, and the team is getting ready to begin its science mission in February. This is an encounter that means a lot for those of us who grew up when Pluto was the ninth planet, and to date the only one we haven't seen close up. That ends in July.
FOUR -- But wait, there's more! Dawn will be entering orbit around the dwarf planet Ceres in March, having left Vesta in September of 2012. Despite having been launched a year later than New Horizons, Dawn will end up being the first spacecraft to have a close encounter with a dwarf planet. On the other hand, Ceres may not be as interesting as Pluto ... but then again, it might. We don't know ahead of time what we'll find, which is part of what makes the trip worthwhile.
FIVE -- While the Dragon 2.0 won't fly this year, tomorrow morning we'll get to find out if they can land a Falcon first stage on an autonomous ocean barge or not. SpaceX is saying they have a 50-50 shot of this thing working right the first time. But I sure wouldn't put money on them not being able to figure it out within a flight or two. Once they work the bugs out, this will allow SpaceX to recover, refurbish, and re-use an enormous chunk of flight hardware that everyone else just throws away. Good news for SpaceX, as well as its shareholders and customers; mildly worrisome for everyone else in the business.
SIX -- It will be a while before anything is known for sure, but my guess is that Scaled Composites will identify what went wrong with VSS Enterprise, fix it, and be ready to go back into test by the end of the year. But that depends on a number of things -- the final NTSB report and whether or not Richard Branson wants to press ahead being the two most important ones.
SEVEN -- And last but not least, the planet-hunter Kepler isn't down for the count, after all. They've managed to work out a mode of operation that will allow some observations to go forward, even with its reduced capability. It may be several years before my #4 observation from last year comes to fruition -- that'll probably require much more capable sensors than we currently have -- but I'm still optimistic we'll find a habitable world Out There fairly soon.
EIGHT -- Nothing new to report on the fusion energy front ... yet. But keep an eye on this. The fact that a company as big as Lockheed has laid its name and reputation on the line tells me that they've got a solid path forward. The odds are that we won't hear anything new until it's demonstration time. This points back to items #5 through #7 from last year, and I'll say it again: while concern is warranted about our power future, panic isn't. More and more, it's looking like we'll have the tools we need when we need them.
NINE -- This is a partial call-back to #5 above ... but I just wanted to point out how far 3-D printing has come. The thrusters they're going to use both for contingency aborts and precision landings? Made by 3-D printing, with metal. Not plastic, metal. Also, a 3-D printer has been delivered to the International Space Station. I wasn't aware that was even possible. Early 3-D printing technology required gravity in order to do its thing. Apparently, they've figured out a way around that. Interestingly enough, the first thing they made with their new 3-D printer was a part for the printer ... which tells me we're that much closer to being able to build a machine that can rebuild itself. Cool, and scary, all at the same time.
TEN -- Please, merciful God, spare us Clinton vs. Bush in 2016. Surely there are other candidates. But I fear that may be how the primaries shake out.
ELEVEN -- What a difference a year makes. Several years of 8-8 futility, and all of a sudden the Cowboys turn into an unstoppable-on-the-road juggernaut. Which sets up an interesting situation this coming Sunday in Green Bay -- the irresistible force meets the immovable object. The Cowboys are undefeated on the road. The Packers are undefeated at home. One of those streaks ends on Sunday.
TWELVE -- Somewhat related: is anyone out there still questioning the wisdom of drafting Zack Martin instead of Johnny Manziel? Anyone? Anyone? Bueller?
THIRTEEN -- While the lower gas prices are nice, something's going on behind the scenes that no one's quite figured out yet. We know that Saudi Arabia spun their taps wide open, what we don't know is why. There are a few possibilities, ranging from the highly likely to the improbable. Increasing the supply drops the price, that's obvious. Question is, who benefits? And who's hurt? Is this intended to put some hurt on the Iranians? Maybe, and a weakened Iran would be a good thing for the Saudis. Do they want to put a squeeze on the Russians? Maybe, insofar as they've provided Iran with backing. Do they want to drive prices low enough to put the resurgent American oil industry in a bind? I tend to think that's an unintended consequence, but I'm just guessing. Low prices put advanced recovery techniques, such as fracking and tar sands, at an unfavorable place on the price curve. But if they see that as such a threat, then ... maybe they're drawing down low enough that it's "smoke 'em while you got 'em" time. But if their reserves were getting that low, the smart play would be to lean it out as long as possible, wouldn't it? In any case, this bears close attention, and you should probably keep an eye on it.
FOURTEEN -- When Autocorrect gets good enough to make this site obsolete, then it's time to worry about Artificial Intelligence.
FIFTEEN -- (Added 11Jan15) Yep. Definitely regretting this motif.
Friday, January 02, 2015
Sesquicentennial, Part XLII: The Penultimate Campaign
--FIRST -PREV NEXT-
"An army marches on its stomach." -- Napoleon Bonaparte
Atlanta had fallen, but John Bell Hood knew that wasn't necessarily the end. Sherman's men needed food, and supply. These, he'd have to get from the North. So, reasoned Hood, if he stood astride Sherman's line of supply, he'd have to come out and give battle on Hood's terms. It was with this general intent that Hood marched to the northwest, more or less leaving Georgia the way Sherman came in.
Sherman mounted a brief, half-hearted attempt to follow, then apparently gave it up as a bad idea. This perplexed Hood. He attacked Union forces at Spring Hill, then at Franklin, finally attacking Nashville itself in mid-December, but not a peep came from Sherman. Did Sherman care nothing for his lines of supply?
Hood, in the end, accomplished nothing but the destruction of the Army of Tennessee as an actual fighting force. I wonder if Hood knew what Sherman's plan actually was.
Because Sherman had deduced the dread secret of industrial-age war. Armies marched on their stomachs, yes. But that's a sword that cuts both ways. There are more ways than one to deny Lee's army of its supply. And there are more ways than one of supplying his own men at the same time. And Georgia's rich farmlands had not, as yet, felt the hard hand of war...
This was the bold plan he'd advanced to Grant and Lincoln, so bold that it bordered on suicidal rashness: cut loose. Head southeast towards Savannah, relying on the farmlands themselves for his sustenance. On the way, tear up telegraph wires, rail lines, and anything else of military significance. He had over sixty thousand men, even after cutting General Thomas and his men loose to keep Hood occupied in Tennessee. He had detailed maps drawn up, using data from the 1860 census, showing where the richest farms and plantations were, and what they'd be likely to have.
"I can make this march," Sherman wrote in a telegram to Grant, "And I will make Georgia howl!"
In opposition, General William Hardee could only muster some thirteen thousand troops with which to defend Georgia and the Carolinas. In open country ... that wouldn't be much of a fight. Hardee, not being an idiot, wasn't about to fight in open country. He fortified the approaches to Savannah as best he could, and awaited Sherman's arrival.
There were a few skirmishes along the way, but nothing really worth mentioning. The March itself remains somewhat controversial. His supporters have called Sherman the first modern general, the first to truly understand that by attacking the Confederacy's logistical underpinnings, he was taking the most direct path possible to defeating the Confederate armies in the field. His detractors call him many things -- some not repeatable in a family publication -- but also lay the charge of war criminal at his feet for making war upon civilians. He had an answer for them:
"You cannot qualify war in harsher terms than I will. War is cruelty, and you cannot refine it; and those who brought war into our country deserve all the curses and maledictions a people can pour out. I know I had no hand in making this war, and I know I will make more sacrifices to-day than any of you to secure peace. But you cannot have a peace and a division of our country. If the United States submits to a division now, it will not stop, but will go on until we reap the fate of Mexico, which is eternal war. The United States does and must assert its authority, wherever it once had power; for if it relaxes one bit to pressure it is gone, and I believe that such is the national feeling."
Sherman believed that what he called "Hard War" (and what we would call today "Total War") made for a shorter conflict, and would lead to a swifter peace with less overall bloodshed. And to be sure, Sherman had drawn up orders to the effect that civilians were to be left unmolested, so long as they did not impede the army's march. Their excess produce would be confiscated, to be sure, but their persons were to be safe.
By mid-December, Sherman's army was arrayed outside of Savannah, and Sherman went about the business of reducing the fortifications that prevented his access to the sea -- and with it, communication with the Union Naval forces in command there. On December 17th, having made contact with Admiral John Dahlgren, he issued an ultimatum to General Hardee in Savannah. Surrender and accept generous terms, or resist and face obliteration. Hardee took a third option: he and his troops slipped out and escaped. In his stead, the mayor of Savannah surrendered the city to Sherman.
A few days later, Sherman telegraphed Lincoln:
"I beg to present you as a Christmas gift the City of Savannah, with one hundred and fifty guns and plenty of ammunition, also about twenty-five thousand bales of cotton."
Unwritten, but obviously implied and easily seen by anyone paying attention, was the fact that a Union army would roam at will through the Confederate heartland. That the Confederate army was powerless to defend the Confederacy. This is the point Lee had hoped to make with his two invasions of the North ... but didn't swing enough heavy iron to make the point stick.
Sherman had heavy iron to swing, and plenty to spare. The only question remaining was, who's next?
Actually, that's a trick question. Sherman was heading North, along the coast, to link up with Grant. South Carolina would be next to feel the sting. And there wasn't a blessed thing Jefferson Davis could do to stop him.
"An army marches on its stomach." -- Napoleon Bonaparte
Atlanta had fallen, but John Bell Hood knew that wasn't necessarily the end. Sherman's men needed food, and supply. These, he'd have to get from the North. So, reasoned Hood, if he stood astride Sherman's line of supply, he'd have to come out and give battle on Hood's terms. It was with this general intent that Hood marched to the northwest, more or less leaving Georgia the way Sherman came in.
Sherman mounted a brief, half-hearted attempt to follow, then apparently gave it up as a bad idea. This perplexed Hood. He attacked Union forces at Spring Hill, then at Franklin, finally attacking Nashville itself in mid-December, but not a peep came from Sherman. Did Sherman care nothing for his lines of supply?
Hood, in the end, accomplished nothing but the destruction of the Army of Tennessee as an actual fighting force. I wonder if Hood knew what Sherman's plan actually was.
Because Sherman had deduced the dread secret of industrial-age war. Armies marched on their stomachs, yes. But that's a sword that cuts both ways. There are more ways than one to deny Lee's army of its supply. And there are more ways than one of supplying his own men at the same time. And Georgia's rich farmlands had not, as yet, felt the hard hand of war...
This was the bold plan he'd advanced to Grant and Lincoln, so bold that it bordered on suicidal rashness: cut loose. Head southeast towards Savannah, relying on the farmlands themselves for his sustenance. On the way, tear up telegraph wires, rail lines, and anything else of military significance. He had over sixty thousand men, even after cutting General Thomas and his men loose to keep Hood occupied in Tennessee. He had detailed maps drawn up, using data from the 1860 census, showing where the richest farms and plantations were, and what they'd be likely to have.
"I can make this march," Sherman wrote in a telegram to Grant, "And I will make Georgia howl!"
In opposition, General William Hardee could only muster some thirteen thousand troops with which to defend Georgia and the Carolinas. In open country ... that wouldn't be much of a fight. Hardee, not being an idiot, wasn't about to fight in open country. He fortified the approaches to Savannah as best he could, and awaited Sherman's arrival.
There were a few skirmishes along the way, but nothing really worth mentioning. The March itself remains somewhat controversial. His supporters have called Sherman the first modern general, the first to truly understand that by attacking the Confederacy's logistical underpinnings, he was taking the most direct path possible to defeating the Confederate armies in the field. His detractors call him many things -- some not repeatable in a family publication -- but also lay the charge of war criminal at his feet for making war upon civilians. He had an answer for them:
"You cannot qualify war in harsher terms than I will. War is cruelty, and you cannot refine it; and those who brought war into our country deserve all the curses and maledictions a people can pour out. I know I had no hand in making this war, and I know I will make more sacrifices to-day than any of you to secure peace. But you cannot have a peace and a division of our country. If the United States submits to a division now, it will not stop, but will go on until we reap the fate of Mexico, which is eternal war. The United States does and must assert its authority, wherever it once had power; for if it relaxes one bit to pressure it is gone, and I believe that such is the national feeling."
Sherman believed that what he called "Hard War" (and what we would call today "Total War") made for a shorter conflict, and would lead to a swifter peace with less overall bloodshed. And to be sure, Sherman had drawn up orders to the effect that civilians were to be left unmolested, so long as they did not impede the army's march. Their excess produce would be confiscated, to be sure, but their persons were to be safe.
By mid-December, Sherman's army was arrayed outside of Savannah, and Sherman went about the business of reducing the fortifications that prevented his access to the sea -- and with it, communication with the Union Naval forces in command there. On December 17th, having made contact with Admiral John Dahlgren, he issued an ultimatum to General Hardee in Savannah. Surrender and accept generous terms, or resist and face obliteration. Hardee took a third option: he and his troops slipped out and escaped. In his stead, the mayor of Savannah surrendered the city to Sherman.
A few days later, Sherman telegraphed Lincoln:
"I beg to present you as a Christmas gift the City of Savannah, with one hundred and fifty guns and plenty of ammunition, also about twenty-five thousand bales of cotton."
Unwritten, but obviously implied and easily seen by anyone paying attention, was the fact that a Union army would roam at will through the Confederate heartland. That the Confederate army was powerless to defend the Confederacy. This is the point Lee had hoped to make with his two invasions of the North ... but didn't swing enough heavy iron to make the point stick.
Sherman had heavy iron to swing, and plenty to spare. The only question remaining was, who's next?
Actually, that's a trick question. Sherman was heading North, along the coast, to link up with Grant. South Carolina would be next to feel the sting. And there wasn't a blessed thing Jefferson Davis could do to stop him.
Friday, December 19, 2014
Two Bad Days, One Good One
Flight test is a harsh, unforgiving business.
Modern computer modeling can sometimes give you an incorrect appreciation of this. You think you have all the angles figured. You think you've accounted for everything. You think you've analyzed the stresses down to the last nut, bolt, rivet and weld. But there's a small problem ... one of the unfortunate implications of Godel's Incompleteness Theorem is that every model is necessarily incomplete. That is, the only complete model of a thing is the thing itself.
So ... the only way to find out how the thing behaves is to go try it out for real. To try it in the real world, where there are few (and sometimes only one) way to succeed, and innumerable ways to fail.
That's not always a bad thing, by the way; failure can be instructive. But those lessons sometimes come with a staggeringly high price tag.
On the 28th of October, Orbital Sciences Corporation had an Antares launch vehicle sitting on the pad at Wallops Island in Virginia, set to carry a Cygnus resupply pod to the International Space Station. The Antares rocket's first stage is powered by two AJ-26 rocket engines. The AJ-26 is a repackaging by Aerojet General of the Soviet-built NK-33. Originally, the NK-33 was intended to be the main engine for the N-1 lunar booster, with thirty in the first stage and eight in the second stage.
Someone ... oh, God, someone should have thought this through. Because the N-1 "flew" four times, without much variation in the outcome.
Anyway, recycling old rocket bits is Orbital's stock in trade. When they found a bunch of perfectly good rocket engines sitting in a warehouse, someone thought "Score!" Which is how two ex-Soviet engines ended up in an American rocket. Engines, by the way, that were notorious for trying to eat their own turbopumps. Which is more or less how this happened.
At some point you have to wonder if the actual purpose of the NK-33 was the conversion of fuel and structure into shrapnel and combustion by-products. Needless to say, Orbital is now looking for a new engine for Antares. (Addendum, 27Dec14: I'd have expected them to look for a non-Russian engine, but ... yeah, they're using another Russian engine. On the upside, the RD-181 is built in the same factory as the RD-180. The RD-180 has proven fairly reliable so far. On the downside, this puts Antares at the mercy of whatever the hell Putin decides to pull this month. They may yet regret this choice.)
The good news is that nothing was hurt, apart from OSC's pride. The same can't be said for the test mishap suffered by VSS Enterprise.
On October 31st, VSS Enterprise dropped from its White Knight Two carrier airplane for its fourth powered flight, and its thirty-sixth flight overall. Virgin and Scaled Composites had, by all accounts, been pursuing a long and fairly conservative flight test program, expanding the flight envelope bit by bit with each new powered flight. It should have been a fairly routine outing. The full NTSB report won't be available for some time, but what seems to have happened is that the copilot hit the "feather" switch too soon, while the rocket engine was still burning. The sudden nose-down pitch caused the ship to break up in flight, killing both crew on board. (Addendum, 27Jan15: Rarely have I been happier to have been wrong. Peter Siebold, while seriously injured, was not killed in the crash.)
I'm reserving judgement, here. I don't know enough about how it operates ... but it does seem to me that switch should have a guard of some kind. By way of comparison, on the C-130, the paratrooper "jump" light switch has a metal flange that will not allow you to turn that light on unless you've already opened the jump door. And maybe there's already something like that there, and the crew got confused.
Truth is, we just don't know yet, and probably won't know until the report is released.
There is some good news to go along with the bad, though. In early December, there was a test flight of the new Orion crew capsule. NASA looks like they've shook off whatever was ailing them back in their Ares-1X days. On December 5th, a test version of the Orion spacecraft was launched on a Delta IV Heavy booster on a two-orbit test flight. The launch and re-entry both came off without a hitch.
I had heard Ares-1X described as "a low-fidelity test of a bad design." It's not really fair to say that of Orion. Orion took two passes through the Van Allen radiation belts, and the Delta second stage fired a second time on the last orbit, to accelerate into re-entry. The peak deceleration was 8.5 times the force of gravity. This was a fairly rigorous shakedown cruise. It was a legitimate test that NASA could have failed.
They didn't.
Now, it's probably still true that Dragon V2 will beat a manned Orion into space, because Orion is paced by NASA funding and Dragon is paced by the whims of an eccentric billionaire, but once it does fly, Orion will be a top-notch ship. Of that, I'm very confident ... and a few years ago, I wasn't.
Flight test is a harsh, unforgiving business. Its lessons are paid for in blood. But we do learn, and in the end, the lessons are worth it.
Modern computer modeling can sometimes give you an incorrect appreciation of this. You think you have all the angles figured. You think you've accounted for everything. You think you've analyzed the stresses down to the last nut, bolt, rivet and weld. But there's a small problem ... one of the unfortunate implications of Godel's Incompleteness Theorem is that every model is necessarily incomplete. That is, the only complete model of a thing is the thing itself.
So ... the only way to find out how the thing behaves is to go try it out for real. To try it in the real world, where there are few (and sometimes only one) way to succeed, and innumerable ways to fail.
That's not always a bad thing, by the way; failure can be instructive. But those lessons sometimes come with a staggeringly high price tag.
On the 28th of October, Orbital Sciences Corporation had an Antares launch vehicle sitting on the pad at Wallops Island in Virginia, set to carry a Cygnus resupply pod to the International Space Station. The Antares rocket's first stage is powered by two AJ-26 rocket engines. The AJ-26 is a repackaging by Aerojet General of the Soviet-built NK-33. Originally, the NK-33 was intended to be the main engine for the N-1 lunar booster, with thirty in the first stage and eight in the second stage.
Someone ... oh, God, someone should have thought this through. Because the N-1 "flew" four times, without much variation in the outcome.
Anyway, recycling old rocket bits is Orbital's stock in trade. When they found a bunch of perfectly good rocket engines sitting in a warehouse, someone thought "Score!" Which is how two ex-Soviet engines ended up in an American rocket. Engines, by the way, that were notorious for trying to eat their own turbopumps. Which is more or less how this happened.
At some point you have to wonder if the actual purpose of the NK-33 was the conversion of fuel and structure into shrapnel and combustion by-products. Needless to say, Orbital is now looking for a new engine for Antares. (Addendum, 27Dec14: I'd have expected them to look for a non-Russian engine, but ... yeah, they're using another Russian engine. On the upside, the RD-181 is built in the same factory as the RD-180. The RD-180 has proven fairly reliable so far. On the downside, this puts Antares at the mercy of whatever the hell Putin decides to pull this month. They may yet regret this choice.)
The good news is that nothing was hurt, apart from OSC's pride. The same can't be said for the test mishap suffered by VSS Enterprise.
On October 31st, VSS Enterprise dropped from its White Knight Two carrier airplane for its fourth powered flight, and its thirty-sixth flight overall. Virgin and Scaled Composites had, by all accounts, been pursuing a long and fairly conservative flight test program, expanding the flight envelope bit by bit with each new powered flight. It should have been a fairly routine outing. The full NTSB report won't be available for some time, but what seems to have happened is that the copilot hit the "feather" switch too soon, while the rocket engine was still burning. The sudden nose-down pitch caused the ship to break up in flight, killing both crew on board. (Addendum, 27Jan15: Rarely have I been happier to have been wrong. Peter Siebold, while seriously injured, was not killed in the crash.)
I'm reserving judgement, here. I don't know enough about how it operates ... but it does seem to me that switch should have a guard of some kind. By way of comparison, on the C-130, the paratrooper "jump" light switch has a metal flange that will not allow you to turn that light on unless you've already opened the jump door. And maybe there's already something like that there, and the crew got confused.
Truth is, we just don't know yet, and probably won't know until the report is released.
There is some good news to go along with the bad, though. In early December, there was a test flight of the new Orion crew capsule. NASA looks like they've shook off whatever was ailing them back in their Ares-1X days. On December 5th, a test version of the Orion spacecraft was launched on a Delta IV Heavy booster on a two-orbit test flight. The launch and re-entry both came off without a hitch.
I had heard Ares-1X described as "a low-fidelity test of a bad design." It's not really fair to say that of Orion. Orion took two passes through the Van Allen radiation belts, and the Delta second stage fired a second time on the last orbit, to accelerate into re-entry. The peak deceleration was 8.5 times the force of gravity. This was a fairly rigorous shakedown cruise. It was a legitimate test that NASA could have failed.
They didn't.
Now, it's probably still true that Dragon V2 will beat a manned Orion into space, because Orion is paced by NASA funding and Dragon is paced by the whims of an eccentric billionaire, but once it does fly, Orion will be a top-notch ship. Of that, I'm very confident ... and a few years ago, I wasn't.
Flight test is a harsh, unforgiving business. Its lessons are paid for in blood. But we do learn, and in the end, the lessons are worth it.
Friday, November 07, 2014
Sesquicentennial, Part XLI: Decision '64, Part 2
--FIRST -PREV NEXT-
As late in the year as July, President Lincoln's re-election chances were looking sketchy, at best. The Republican Party was undergoing a split, similar to the one the Democrats suffered in 1860. The war had dragged on far longer than anyone had ever thought possible. One group of voters just wanted the war over, at any cost. The other wanted it won, by any means necessary. Neither group was happy with Mr. Lincoln.
But events conspired to deliver Lincoln a reprieve. One, we've already talked about: Sherman's capture of Atlanta. The other wasn't nearly as dramatic, but still important. A Union army under General Philip Sheridan had routed the Confederate army defending the Shenandoah Valley, and Sheridan had rendered the once-productive farmlands to a state such that it was said that a bird flying overhead would have to bring along its own rations. As is so often true, victory covers a multitude of sins. The Radical Republicans were somewhat mollified by the improved fortunes -- and the vindication of Lincoln's overall war plans those improved fortunes indicated. Fremont did get something for his trouble, though; as his price to drop his candidacy, he did manage to get the Postmaster General replaced.
History does not record what beef Fremont had with the existing Postmaster General, who was presumably doing an acceptable job.
Incidentally, there was no Confederate Presidential election. The Confederate Presidency was limited to a single six-year term, with the first actual election scheduled for 1866. Provided, of course, that the Confederacy would last so long.
The November election, when it came, was something of an anticlimax. The popular vote was much closer than the Electoral vote. Although the popular vote counts weren't what you'd call close -- Lincoln won 55% of the vote to McClellan's 45%. In the Electoral College the totals were much more lopsided, 212 to 21. McClellan won his home state of New Jersey, Delaware, and Kentucky. That was about it. Many Northern voters were tired of the war -- McClellan did quite well, winning a sprinkling of counties across the country -- but not enough of them were ready to throw in the towel just yet. With the events of the last year, particularly the last few months, they could smell a sea change.
And ... so could Southerners.
I think they knew they were doomed. Depending on who you ask they'll draw the line here or there, the point at which they knew the jig was up. Some will say Gettysburg, others Vicksburg. General D.H. Hill said Chickamauga was the breaking point ... ironically, a Confederate victory, but one they were unable to exploit. "It seems to me the élan of the Southern soldier was never seen after Chickamauga," Hill would later write. "He would fight stoutly to the last, but after Chickamauga, with the sullenness of despair and without the enthusiasm of hope." But I think it was the re-election of Lincoln that well and truly drew a line under it. They first pinned their hopes on a foreign intervention that never came, and then upon a Northern war-weariness and exhaustion that would not come in time. Undergirding it all was a reliance upon the daring and dash of their soldiers, and now that was gone, too.
But fight they would, with as much as they had, and with all the time they had left.
And so the war rolled on. The Southern armies still in the field had to be subdued. General Sherman in Atlanta had advanced a ... somewhat unconventional proposal to Grant and Lincoln. And, for all its risk and all his worries about it, Lincoln finally decided to let Sherman off the chain.
It was time to end this.
As late in the year as July, President Lincoln's re-election chances were looking sketchy, at best. The Republican Party was undergoing a split, similar to the one the Democrats suffered in 1860. The war had dragged on far longer than anyone had ever thought possible. One group of voters just wanted the war over, at any cost. The other wanted it won, by any means necessary. Neither group was happy with Mr. Lincoln.
But events conspired to deliver Lincoln a reprieve. One, we've already talked about: Sherman's capture of Atlanta. The other wasn't nearly as dramatic, but still important. A Union army under General Philip Sheridan had routed the Confederate army defending the Shenandoah Valley, and Sheridan had rendered the once-productive farmlands to a state such that it was said that a bird flying overhead would have to bring along its own rations. As is so often true, victory covers a multitude of sins. The Radical Republicans were somewhat mollified by the improved fortunes -- and the vindication of Lincoln's overall war plans those improved fortunes indicated. Fremont did get something for his trouble, though; as his price to drop his candidacy, he did manage to get the Postmaster General replaced.
History does not record what beef Fremont had with the existing Postmaster General, who was presumably doing an acceptable job.
Incidentally, there was no Confederate Presidential election. The Confederate Presidency was limited to a single six-year term, with the first actual election scheduled for 1866. Provided, of course, that the Confederacy would last so long.
The November election, when it came, was something of an anticlimax. The popular vote was much closer than the Electoral vote. Although the popular vote counts weren't what you'd call close -- Lincoln won 55% of the vote to McClellan's 45%. In the Electoral College the totals were much more lopsided, 212 to 21. McClellan won his home state of New Jersey, Delaware, and Kentucky. That was about it. Many Northern voters were tired of the war -- McClellan did quite well, winning a sprinkling of counties across the country -- but not enough of them were ready to throw in the towel just yet. With the events of the last year, particularly the last few months, they could smell a sea change.
And ... so could Southerners.
I think they knew they were doomed. Depending on who you ask they'll draw the line here or there, the point at which they knew the jig was up. Some will say Gettysburg, others Vicksburg. General D.H. Hill said Chickamauga was the breaking point ... ironically, a Confederate victory, but one they were unable to exploit. "It seems to me the élan of the Southern soldier was never seen after Chickamauga," Hill would later write. "He would fight stoutly to the last, but after Chickamauga, with the sullenness of despair and without the enthusiasm of hope." But I think it was the re-election of Lincoln that well and truly drew a line under it. They first pinned their hopes on a foreign intervention that never came, and then upon a Northern war-weariness and exhaustion that would not come in time. Undergirding it all was a reliance upon the daring and dash of their soldiers, and now that was gone, too.
But fight they would, with as much as they had, and with all the time they had left.
And so the war rolled on. The Southern armies still in the field had to be subdued. General Sherman in Atlanta had advanced a ... somewhat unconventional proposal to Grant and Lincoln. And, for all its risk and all his worries about it, Lincoln finally decided to let Sherman off the chain.
It was time to end this.
Friday, October 31, 2014
Happy Halloween!
There are some people who claim that the last 20-odd minutes of 2001 were originally intended to have a score by Pink Floyd. It's hard to disagree.
Happy Halloween, everyone!
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