And the original developers behind Orion did indeed envision using it to lift very large craft. This was back in the late 1950s, atmospheric testing of nukes was common amongst them that had 'em. Talk about direct to Mars...
Ever seen film footage of the test models? Small things, using grenade-size explosive charges, but pretty impressive considering. The number of (small) nukes needed to lift the real thing beyond the atmosphere wouldn't have amounted to as much as some of the strategic weapons they were testing anyway. Indeed, as much as anything else, Projects Argus and Starfish (high atmospheric/ionospheric detonations, in the late 1950s/early 1960s) put the damper on Orion because it showed the adverse effects of ionospheric detonation. The EMP from Starfish blew out phone lines and street lights in Hawaii, and even fused car ignitions.
... my closest living relative is probably my mother or maybe my father.
Maybe if you're an only child. Otherwise it's your brother(s) and sister(s).
Uh, no. Genetically speaking (we were, weren't we?), you have 50% of your mother's and 50% of your father's genes. On average, though, you only share about 25% of a given sibling's genes. (Identical twins excluded, of course.) It's possible to share more or less than 25%, but less probable.
If you have kids, they're closer genetically to you (50%) than your siblings are.
(Of course, if you married your sister, all bets are off, and don't even get started on being your own grandpa.)
That reminds me, down in the basement with the other Halloween stuff I've got a Talking Skull. Cost about $5 in a post-Halloween sale. The jaw moves when it's speaking (I wouldn't exactly call it synch'd), and voice is provided via an included microphone and cord.
Replace the mike with a cable to a computer's sound card, prerecord some messages, and away you go.
(And speaking of Billy Bass, didn't Linux Journal or maybe one of the hardware hobbyist magazines a couple of years back run an article on how to wire that up to your computer? Ah, here we go.)
If it[']s easier for people to legally own firearms it[']s also easier for criminals to own firearms. Make firearms illegal then [fewer] criminals will have them. Yes, there will still be a few that have them, but far fewer.
Not the point. The ratio of criminal gun owners to law abiding gun owners will change from being a small fraction to being an overwhelming multiple.
If gun ownership is legal, a criminal, even a gun-toting one, has to weigh the risk that his intended victim might be armed. If it's illegal, the risk to the criminal is vastly reduced.
There's no reason to be afraid of armed law-abiding folk unless you're a criminal. If some nutter does go on a shooting spree (and face it, the odds of that are far lower than the odds of encountering a criminal), then with an armed citizenry you're more likely to have someone able to take the nutter out before he hurts too many people.
If you're really worried about normally law-abiding citizens flipping out and going on a killing spree, you'd better make gasoline (among thousands of other products) illegal too.
One person just can't accomplish that kind of violence with any kind of weapon short of a gun.
Not at all true. One of the worst mass-murders in the US up until 9/11 (which didn't involve guns either) was committed by someone who was pissed off after being bounced from a disco and came back and firebombed the place. All it took was a gallon or two of gasoline and some matches.
If he'd had a gun, the death toll would have been much lower.
The weight of evidence here falls in favor of an armed populace for reducing violent crime.
As the saying goes, an armed society is a polite society. Well, eventually anyway. There used to be a time when many countries -- even England -- allowed and even encouraged gentlemen to go armed (although more likely with a sword than a pistol). After all, you don't have to worry about a gentle man using arms offensively.
Pretty much a tautology, I'd say. Damn hard to have a shooting with no guns involved, although I suppose there are ways of making a bullet go off without a gun.
Now, how many guns were involved in the 9/11/01 attacks and over 3000 casualties? None at all.
Ten years ago they had the excuse that the web was still young and that standards were still evolving. Were there even any web "standards" as such in 1996? (Other than a general consensus that the inventor of the blink tag deserved to have his eyelids held open while forced to stare at a strobelit picture of the goatse.cx guy.)
Mostly widely used, perhaps, but not "popular". The word "popular" implies that a choice has been made -- most people just take the default because they don't know any better, or don't have a choice (eg corporate mandate at work). Heart disease is the leading cause of death in the US, followed closely by cancer, but I wouldn't exactly call either of those the "most popular".
Others say they also stay current to avoid headaches and fire drills.
Strange. I always though staying current was a headache and a fire drill.
(Heck, I still use 9.x on my kids' computers. Works fine for their software, and they're usually not on the internet. When they are it's behind a NATed firewall and using firefox.)
Why would a terrorist need more than a single hit? It seems to me that there are lots of vital structures on an airplane that, when hit by a single bullet, could cause serious problems.
Um, no.
Commercial aircraft are designed with multiple redundant systems. They are designed to withstand things like engines disintegrating and spewing turbine blades all over the place, bird strikes and other random foreign object impacts, lightning strikes, landing gear tire explosions, and miscellaneous failures like random hydraulic line ruptures or doors not properly latched. An Aloha Airlines 737 successfully flew to an airport and landed after a large section of fuselage ripped off because of excessive corrosion and pressurization cycle stress fractures.
Boeing learned aircraft design lessons by examining WW II bombers that returned from missions full of flak damage. Were the holes were, they knew they'd designed it right. In areas where no damage was found, they knew that aircraft that had been hit there hadn't made it back -- so they redesigned that area.
Most places on an airliner where a bullet hit would probably go unnoticed until the ground inspection crew noticed the hole or dent.
(Heck, even a shoulder-launched SAM might not do significant damage. There was a great photo in Aviation Week some years back, of a private jet (Gulfstream? Citation? I forget which) owned by some African country (presidental plane) that had been fired on and hit. Blew one of the engine pods apart. The rest of the aircraft, and the pilots, essentially treated at as a "routine" catastrophic engine failure and continued on to friendlier territory on the remaining engine.)
Oh, come on, that's the best you can do? How lame. That you have purple skin, gills, and feathery antennae isn't proved either.
Let me rephrase my original "First, you're assuming that greenhouse gases are a significant contributer to global warming. This is not proved," then. "First, you're assuming that greenhouse gases are a significant contributer to global warming. Numerous alternatives to this hypothesis (e.g. fluctuations in solar output, or that 'global' warming is a misinterpretation of observations) have not been disproved."
While definetly greener than burning oil this still contributes as much to global warming? Right?
Wrong.
First, you're assuming that greenhouse gases are a significant contributer to global warming. This is not proved, beyond the obvious fact that without any greenhouse effect at all the average temperature of Earth would be around freezing. There is nothing to prove a causal relationship between elevated CO2 levels and warming. Indeed, it could be that warming (perhaps caused by increased solar output) has increased CO2 levels (warmer water holding less dissolved CO2, etc).
Second, even if greenhouse gases were causing global warming, you're assuming that the combustion products of methane (H2O and CO2) are significant greenhouse gases. In fact, methane is a stronger greenhouse gas than CO2 is. Water is actually a stronger greenhouse gas than either by about an order of magnitude, but burning methane (or fossil fuel, for that matter) doesn't significantly add to the atmosphere's H2O load because that's pretty much in equilibrium anyway, between 75% of Earth's surface being open water and the fact that it frequently precipitates out.
That said, reducing dependence on foreign oil is worth doing for other reasons, as is reducing dependence on any fossil fuel as an energy source (waste of a good chemical feedstock).
Changing jobs is a non-trivial decision, and depends on many factors beyond simply whether or not you like your job (or rather, how much you like/dislike your job). Job market, location, other responsibilities (family, etc) all factor in to just how bad it has to get before you jump ship, or how easy it is to find somthing else to jump to.
Even if you're a freelance contractor and used to switching jobs a lot, you can't just bail at the first thing that annoys you -- unless your talent happens to be so great and specialized that you can still get work with that kind of reputation. Which is improbable.
Ever hear of carbon paper? (Hint, the "CC" field in email is a legacy abbreviation for "carbon copy".) Carbon paper was a sheet of very thin paper coated with a slightly waxy, dark (carbon) material on one side that when placed (carbon side down) on a sheet of paper and pressed, would leave a mark where the pressure was. Now, place a regular sheet of paper on top of that, roll the whole sandwich into the platen (roller) of a typewriter (remember those?) and type away. As the letters (on little hammers - until Selectrics and daisy wheels came along) slam into the ribbon, leaving their mark on the top sheet, the pressure also carries through the carbon paper to leave a duplicate impression on the 2nd layer of paper beneath. Voila, a carbon copy.
Someone with a really heavy hand on a manual, or a good electric typewriter, could easily make two and perhaps three (about the limit, and needing thin paper) carbon copies at a time with a sufficiently thick sandwich of paper and carbon paper.
There also existed -- well, maybe not in 1910 but certainly before the invention of the xerograph -- photocopiers. They used photosensitive paper and developing fluid. That was the big plus of the Xerox -- it was dry (hence the name).
For a much more detailed look at the evolution of Superman's powers -- and the character and backstory in general -- there's a pretty detailed history on the Superman Comics website (which includes reprints of various issues over the ages).
I grew up on the "silver age" Superman, which pretty much matches the movies. Jerry Siegel was back at DC Comics then, and SF writers like Edmond Hamilton and Otto Binder were contributing. A real SF twist on a lot of the stories back then, and set the backstory for much that came later.
The Russians have also been known to launch in the middle of a blizzard.
That's one thing that basing your launchers on ICBM technology gets you. After all, if it comes down to it, you can't hold up your ICBM launches for a little inclement weather.
Designing a vehicle with a safe abort mode in all phases of flight would help too (think "commercial aircraft") -- but vertical takeoff/horizontal landing just doesn't do it, and especially not when you've got SRBs that have to burn for two full minutes once lit -- and you can't separate them (or from them) while burning.
With 12 million illegal immigrants, the US doesn't need robots.
+5, insightful.
Well, not strictly true perhaps -- there are tasks for robots that even immigrants won't (or at least, shouldn't ought to have to) do. Bomb disposal, reactor leak inspection, and so forth. But don't buy into the myth that there are jobs that "Americans won't do" either -- that conveniently avoids the other half of the equation: "at the wages offered". Raise the offered wages and you'll find takers.
Raising the wages (and I don't mean simply by mandating a raise in the minimum wage -- that either causes another round of inflation as everything else increases to adjust, or drives smaller businesses out of business, or both) also makes robots/automation more competitive, and stimulates further research into robotics. Much immigrant (and for that matter, off-shored) labor is repetitive tasks that require a little bit more intelligence than current robots are capable of -- a lot of agricultural labor, for example. (Been there, done that myself as a student, planting tobacco. Just need enough intelligence to pick a seedling out of the bin and place it the right way up in the gripper of the mechanism that actually plants it in the ground -- and have to keep up with the machine.)
Me, I'm wating for iRobot or somebody else to develop a grass cutting robot that actually works. One that pulls dandelions too would be perfect.
If any aircraft deploys its gear at the wrong time (think airliner at 500 knots, or a fighter at Mach 2), it's a loss of vehicle scenario. So what? If the cargo bay doors won't close, that Orbiter ain't coming home (at least not in one piece.)
There are interlocks to prevent things like accidental gear deployment, and Shuttle software is amongst the most bug-free ever written. Plenty of other things the computers can hypothetically screw up besides the landing gear, but the computers are still plugged into them.
Conversely, if the Orbiter had a pressurization problem on re-entry (as happened to an early Soyuz, in that case killing the crew) and the crew blacked out -- well, tough luck if nobody is concious to lower the gear, even if the computers can guide it all the way to touch down.
In response, the office of Governor Mitt Romney issued a statement on Tuesday, saying that the executive branch would continue with the standards implementation plan. "Senator Pacheco is wrong on the facts and wrong on the law. We are committed to an open-standards approach that fully takes into account all accessibility, cost and statutory requirements," said Felix Browne, an administration spokesman.
Pacheo has been on the wrong side of this for a while. I guess he figured it was time for another headline.
The US didn't see a need for it in the shuttle until now.
More like: the astronauts refused to allow it until now. The Shuttle program, along with the Apollo and Gemini programs before it (and to a lesser extent, Mercury), is pretty much controlled (politically and administratively) from Houston, by astronauts and former astronauts in management positions. Dating back to the original Mercury astronauts, they have insisted on an element of manual control with no computer in the loop. This is partially a control issues (recall the original astronauts were almost all test pilots), and partially job security and ego. The use of chimpanzees on the first couple of Mercury flights led to some embarrassing comparisons.
While few of today's astronaut corps come out of the test pilot tradition, the "mandatory man in the loop" is ingrained into NASA culture, and defended fiercely by JSC (if you don't need men (or women) aboard, do you need a Manned Spaceflight Center?).
Mind, I'm all for putting people in space -- the more the merrier, and what's a little risk if the people are willing to take it? But refusing to install a capability they could have had 20 years ago (and autoland for aircraft goes back way further than that) for ego reasons is stupid.
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Interstellar? No, interplanetary.
And the original developers behind Orion did indeed envision using it to lift very large craft. This was back in the late 1950s, atmospheric testing of nukes was common amongst them that had 'em. Talk about direct to Mars...
Ever seen film footage of the test models? Small things, using grenade-size explosive charges, but pretty impressive considering. The number of (small) nukes needed to lift the real thing beyond the atmosphere wouldn't have amounted to as much as some of the strategic weapons they were testing anyway. Indeed, as much as anything else, Projects Argus and Starfish (high atmospheric/ionospheric detonations, in the late 1950s/early 1960s) put the damper on Orion because it showed the adverse effects of ionospheric detonation. The EMP from Starfish blew out phone lines and street lights in Hawaii, and even fused car ignitions.
I was thinking more along the lines of something by Kinky Friedman:
Now I'm a homo erectus
Got to connect this
Bone that I discovered yesterday.
A bit older than Neandertal, of course.
... my closest living relative is probably my mother or maybe my father.
Maybe if you're an only child. Otherwise it's your brother(s) and sister(s).
Uh, no. Genetically speaking (we were, weren't we?), you have 50% of your mother's and 50% of your father's genes. On average, though, you only share about 25% of a given sibling's genes. (Identical twins excluded, of course.) It's possible to share more or less than 25%, but less probable.
If you have kids, they're closer genetically to you (50%) than your siblings are.
(Of course, if you married your sister, all bets are off, and don't even get started on being your own grandpa.)
That reminds me, down in the basement with the other Halloween stuff I've got a Talking Skull. Cost about $5 in a post-Halloween sale. The jaw moves when it's speaking (I wouldn't exactly call it synch'd), and voice is provided via an included microphone and cord.
Replace the mike with a cable to a computer's sound card, prerecord some messages, and away you go.
(And speaking of Billy Bass, didn't Linux Journal or maybe one of the hardware hobbyist magazines a couple of years back run an article on how to wire that up to your computer? Ah, here we go.)
If it[']s easier for people to legally own firearms it[']s also easier for criminals to own firearms. Make firearms illegal then [fewer] criminals will have them. Yes, there will still be a few that have them, but far fewer.
Not the point. The ratio of criminal gun owners to law abiding gun owners will change from being a small fraction to being an overwhelming multiple.
If gun ownership is legal, a criminal, even a gun-toting one, has to weigh the risk that his intended victim might be armed. If it's illegal, the risk to the criminal is vastly reduced.
There's no reason to be afraid of armed law-abiding folk unless you're a criminal. If some nutter does go on a shooting spree (and face it, the odds of that are far lower than the odds of encountering a criminal), then with an armed citizenry you're more likely to have someone able to take the nutter out before he hurts too many people.
If you're really worried about normally law-abiding citizens flipping out and going on a killing spree, you'd better make gasoline (among thousands of other products) illegal too.
One person just can't accomplish that kind of violence with any kind of weapon short of a gun.
Not at all true. One of the worst mass-murders in the US up until 9/11 (which didn't involve guns either) was committed by someone who was pissed off after being bounced from a disco and came back and firebombed the place. All it took was a gallon or two of gasoline and some matches.
If he'd had a gun, the death toll would have been much lower.
The weight of evidence here falls in favor of an armed populace for reducing violent crime.
As the saying goes, an armed society is a polite society. Well, eventually anyway. There used to be a time when many countries -- even England -- allowed and even encouraged gentlemen to go armed (although more likely with a sword than a pistol). After all, you don't have to worry about a gentle man using arms offensively.
Pretty much a tautology, I'd say. Damn hard to have a shooting with no guns involved, although I suppose there are ways of making a bullet go off without a gun.
Now, how many guns were involved in the 9/11/01 attacks and over 3000 casualties? None at all.
I'm sorry, what was your point again?
Ten years ago they had the excuse that the web was still young and that standards were still evolving. Were there even any web "standards" as such in 1996? (Other than a general consensus that the inventor of the blink tag deserved to have his eyelids held open while forced to stare at a strobelit picture of the goatse.cx guy.)
still the most popular browser
Mostly widely used, perhaps, but not "popular". The word "popular" implies that a choice has been made -- most people just take the default because they don't know any better, or don't have a choice (eg corporate mandate at work). Heart disease is the leading cause of death in the US, followed closely by cancer, but I wouldn't exactly call either of those the "most popular".
That's why they [airplanes] are circular.
What, you mean like these?
Others say they also stay current to avoid headaches and fire drills.
Strange. I always though staying current was a headache and a fire drill.
(Heck, I still use 9.x on my kids' computers. Works fine for their software, and they're usually not on the internet. When they are it's behind a NATed firewall and using firefox.)
Why would a terrorist need more than a single hit? It seems to me that there are lots of vital structures on an airplane that, when hit by a single bullet, could cause serious problems.
Um, no.
Commercial aircraft are designed with multiple redundant systems. They are designed to withstand things like engines disintegrating and spewing turbine blades all over the place, bird strikes and other random foreign object impacts, lightning strikes, landing gear tire explosions, and miscellaneous failures like random hydraulic line ruptures or doors not properly latched. An Aloha Airlines 737 successfully flew to an airport and landed after a large section of fuselage ripped off because of excessive corrosion and pressurization cycle stress fractures.
Boeing learned aircraft design lessons by examining WW II bombers that returned from missions full of flak damage. Were the holes were, they knew they'd designed it right. In areas where no damage was found, they knew that aircraft that had been hit there hadn't made it back -- so they redesigned that area.
Most places on an airliner where a bullet hit would probably go unnoticed until the ground inspection crew noticed the hole or dent.
(Heck, even a shoulder-launched SAM might not do significant damage. There was a great photo in Aviation Week some years back, of a private jet (Gulfstream? Citation? I forget which) owned by some African country (presidental plane) that had been fired on and hit. Blew one of the engine pods apart. The rest of the aircraft, and the pilots, essentially treated at as a "routine" catastrophic engine failure and continued on to friendlier territory on the remaining engine.)
The laws of thermodynamics aren't proved either.
Oh, come on, that's the best you can do? How lame. That you have purple skin, gills, and feathery antennae isn't proved either.
Let me rephrase my original "First, you're assuming that greenhouse gases are a significant contributer to global warming. This is not proved," then. "First, you're assuming that greenhouse gases are a significant contributer to global warming. Numerous alternatives to this hypothesis (e.g. fluctuations in solar output, or that 'global' warming is a misinterpretation of observations) have not been disproved."
Happy now?
Tragedy of the commons.
While definetly greener than burning oil this still contributes as much to global warming? Right?
Wrong.
First, you're assuming that greenhouse gases are a significant contributer to global warming. This is not proved, beyond the obvious fact that without any greenhouse effect at all the average temperature of Earth would be around freezing. There is nothing to prove a causal relationship between elevated CO2 levels and warming. Indeed, it could be that warming (perhaps caused by increased solar output) has increased CO2 levels (warmer water holding less dissolved CO2, etc).
Second, even if greenhouse gases were causing global warming, you're assuming that the combustion products of methane (H2O and CO2) are significant greenhouse gases. In fact, methane is a stronger greenhouse gas than CO2 is. Water is actually a stronger greenhouse gas than either by about an order of magnitude, but burning methane (or fossil fuel, for that matter) doesn't significantly add to the atmosphere's H2O load because that's pretty much in equilibrium anyway, between 75% of Earth's surface being open water and the fact that it frequently precipitates out.
That said, reducing dependence on foreign oil is worth doing for other reasons, as is reducing dependence on any fossil fuel as an energy source (waste of a good chemical feedstock).
Hysteresis.
Changing jobs is a non-trivial decision, and depends on many factors beyond simply whether or not you like your job (or rather, how much you like/dislike your job). Job market, location, other responsibilities (family, etc) all factor in to just how bad it has to get before you jump ship, or how easy it is to find somthing else to jump to.
Even if you're a freelance contractor and used to switching jobs a lot, you can't just bail at the first thing that annoys you -- unless your talent happens to be so great and specialized that you can still get work with that kind of reputation. Which is improbable.
Ah, the innocence of youth.
Ever hear of carbon paper? (Hint, the "CC" field in email is a legacy abbreviation for "carbon copy".) Carbon paper was a sheet of very thin paper coated with a slightly waxy, dark (carbon) material on one side that when placed (carbon side down) on a sheet of paper and pressed, would leave a mark where the pressure was. Now, place a regular sheet of paper on top of that, roll the whole sandwich into the platen (roller) of a typewriter (remember those?) and type away. As the letters (on little hammers - until Selectrics and daisy wheels came along) slam into the ribbon, leaving their mark on the top sheet, the pressure also carries through the carbon paper to leave a duplicate impression on the 2nd layer of paper beneath. Voila, a carbon copy.
Someone with a really heavy hand on a manual, or a good electric typewriter, could easily make two and perhaps three (about the limit, and needing thin paper) carbon copies at a time with a sufficiently thick sandwich of paper and carbon paper.
There also existed -- well, maybe not in 1910 but certainly before the invention of the xerograph -- photocopiers. They used photosensitive paper and developing fluid. That was the big plus of the Xerox -- it was dry (hence the name).
For a much more detailed look at the evolution of Superman's powers -- and the character and backstory in general -- there's a pretty detailed history on the Superman Comics website (which includes reprints of various issues over the ages).
I grew up on the "silver age" Superman, which pretty much matches the movies. Jerry Siegel was back at DC Comics then, and SF writers like Edmond Hamilton and Otto Binder were contributing. A real SF twist on a lot of the stories back then, and set the backstory for much that came later.
The Russians have also been known to launch in the middle of a blizzard.
That's one thing that basing your launchers on ICBM technology gets you. After all, if it comes down to it, you can't hold up your ICBM launches for a little inclement weather.
Designing a vehicle with a safe abort mode in all phases of flight would help too (think "commercial aircraft") -- but vertical takeoff/horizontal landing just doesn't do it, and especially not when you've got SRBs that have to burn for two full minutes once lit -- and you can't separate them (or from them) while burning.
And if the computer were wired to let it lower the gear, that wouldn't be an issue at all.
That has to be one of the more stupid comments I've ever seen on Slashdot. Do you work for NASA?
With 12 million illegal immigrants, the US doesn't need robots.
+5, insightful.
Well, not strictly true perhaps -- there are tasks for robots that even immigrants won't (or at least, shouldn't ought to have to) do. Bomb disposal, reactor leak inspection, and so forth. But don't buy into the myth that there are jobs that "Americans won't do" either -- that conveniently avoids the other half of the equation: "at the wages offered". Raise the offered wages and you'll find takers.
Raising the wages (and I don't mean simply by mandating a raise in the minimum wage -- that either causes another round of inflation as everything else increases to adjust, or drives smaller businesses out of business, or both) also makes robots/automation more competitive, and stimulates further research into robotics. Much immigrant (and for that matter, off-shored) labor is repetitive tasks that require a little bit more intelligence than current robots are capable of -- a lot of agricultural labor, for example. (Been there, done that myself as a student, planting tobacco. Just need enough intelligence to pick a seedling out of the bin and place it the right way up in the gripper of the mechanism that actually plants it in the ground -- and have to keep up with the machine.)
Me, I'm wating for iRobot or somebody else to develop a grass cutting robot that actually works. One that pulls dandelions too would be perfect.
If any aircraft deploys its gear at the wrong time (think airliner at 500 knots, or a fighter at Mach 2), it's a loss of vehicle scenario. So what? If the cargo bay doors won't close, that Orbiter ain't coming home (at least not in one piece.)
There are interlocks to prevent things like accidental gear deployment, and Shuttle software is amongst the most bug-free ever written. Plenty of other things the computers can hypothetically screw up besides the landing gear, but the computers are still plugged into them.
Conversely, if the Orbiter had a pressurization problem on re-entry (as happened to an early Soyuz, in that case killing the crew) and the crew blacked out -- well, tough luck if nobody is concious to lower the gear, even if the computers can guide it all the way to touch down.
Pacheo has been on the wrong side of this for a while. I guess he figured it was time for another headline.
The US didn't see a need for it in the shuttle until now.
More like: the astronauts refused to allow it until now. The Shuttle program, along with the Apollo and Gemini programs before it (and to a lesser extent, Mercury), is pretty much controlled (politically and administratively) from Houston, by astronauts and former astronauts in management positions. Dating back to the original Mercury astronauts, they have insisted on an element of manual control with no computer in the loop. This is partially a control issues (recall the original astronauts were almost all test pilots), and partially job security and ego. The use of chimpanzees on the first couple of Mercury flights led to some embarrassing comparisons.
While few of today's astronaut corps come out of the test pilot tradition, the "mandatory man in the loop" is ingrained into NASA culture, and defended fiercely by JSC (if you don't need men (or women) aboard, do you need a Manned Spaceflight Center?).
Mind, I'm all for putting people in space -- the more the merrier, and what's a little risk if the people are willing to take it? But refusing to install a capability they could have had 20 years ago (and autoland for aircraft goes back way further than that) for ego reasons is stupid.