FleaPlus writes "From studying past solid rocket launch failures, the 45th Space Wing of the US Air Force has concluded that an early abort (up to a minute after launch) of NASA Marshall Flight Center's Ares I rocket would have a ~100% chance of killing all crew (report summary and link), even if the launch escape system were activated. This would be due to the capsule being surrounded until ground impact by a 3-mile-wide cloud of burning solid propellant fragments, which would melt the parachute. NASA management has stated that their computer models predict a safe outcome. The Air Force has also been hesitant to give launch range approval to the predecessor Ares I-X suborbital rocket, since its solid rocket vibrations are violent enough to disable both its steering and self-destruct module, endangering people on the ground."
That said a small leak in the solid rocket motor O-ring seals wasn't anything to be alarmed about.
The same NASA that said we've seen foam strikes on the shuttle for years without any problems, so don't worry about it.
NASA has a problem, too many politicians control nasa instead of "missile men".
Because we all know how no one gets hurt while driving a car. Or just walking during winter.
No, but we have made these activities safe enough that they are routine, boring and reliable.
There is no such thing as 100% safe. The only way to guarantee not being hurt by a car, for example, is to avoid them completely. That would be ridiculous.
My point is that NASA doesn't seem to be taking safety seriously enough. Political considerations seem to be more important to them. NASA should be making steps forwards in safety. To do otherwise is simply crazy and morally wrong.
We don't know how to make it safe or routine yet. In my mind, that's justification to spend the money and figure it out. Unfortunately, too many people think high-efficiency engines, advanced lightweight structures, and durable thermal protection systems just materialize from thin air at some unspecified date in the future, and therefore we should just sit back and do nothing till they appear.
It doesn't work like that. Reliable, cheap space access doesn't just happen. You need to work on it first, and too many don't understand that.
Imagine if, in 1909, the world had collectively decided to stop building new airplanes and just wait until something like the 747 came along. We sure wouldn't have reliable aviation.
If I'm reading this right, the Air Force is saying that in the event of a complete failure (ie, the entire thing going to hell all of a sudden) the chances of survival would be zero.
This doesn't really indicate that chances of survival would be zero in all possible emergency abort scenarios.
The Orion escape system is similar to the Apollo setup; that is, a rocket mounted above the crew capsule is, in the event of an emergency, supposed to yank the capsule off with enough acceleration to get clear of any explosion. Of course, there's an upper limit of how much force you can apply without killing the crew, and on a normal launch, the escape system is just dead weight, despite the fact that it's more powerful then the Atlas rocket that put Mercury capsules into orbit, so there are constraints. Obligatory Wikipedia link. [wikipedia.org]
Fortunately it seems like this is a problem that *could be corrected* fairly easily -- with, say, a propulsion mechanism on the escape capsule, just enough to give enough delta-V that it would clear the debris cloud in time to deploy the parachutes.
From what I understand, the Orion capsule's launch escape system already has a jettison motor [nasa.gov], but it's not enough to take it out of range of the flaming debris. Increasing the range of the motor isn't an option, because the capsule is already too heavy for the Ares I and they can't add even more weight to it.
Even though rockets like DIRECT's and the Ares V would have the "field of flaming solid rocket propellant debris" problem, my impression is that they have a big enough margin that you'd be able to have a launch escape system that could escape the debris cloud.
I am a rocket scientist. The Orion does have an escape motor. And outside of the range specified in the briefing it gets it safely away from the SRB propellant. The problem is due to it being a solid propellant booster, when you decide to get out of Dodge, you only have three choices: Blow up the SRB at the same time, blow it up shortly after the escape motor lights, or don't blow it up at all. For public safety and some other reasons, #3 is not acceptable. #1 is not acceptable because now you're always going to have flaming debris around the capsule. So #2 is the solution with the detail being how long of a delay. NASA's simulation have determined the most optimal time delay, for their purposes. The Air Force has agreed with that value. But that delay is the time the SRB keeps following the capsule. And it's still accelerating. And it's accelerating faster because it no longer has to push the capsule. This is a problem that can occur with ANY solid propellant choice, so the Direct crowd and NASA's shuttle alternative may also have this potential problem. Only a purely liquid propellant vehicle that could be shutdown immediately on activating of the escape motor could avoid this problem.
From the Air Force's point of view, this would not affect Ares' launch as long as the flight termination system works--Air Force is responsible for public safety, not the astronauts, that's NASA responsibility. Air Force sent their analysis to NASA, NASA (someone at NASA) made it public.
by Anonymous Coward
on Saturday July 18, @10:57PM (#28745367)
It did actually happen. A solid rocket failure is how Challenger went.
Nitpick: The Challenger SRBs were fine. The external tank failed.
The SRBs leaked a bit of fire through the O-ring, and that fire meant that one of the SRBs cut itself away from the external tank - the attachment at the bottom of the tank failed, the one at the top didn't, and that was enough to plow the nose of the SRB into the tip of the external tank.
*boom*
The external tank tore itself apart from the aerodynamic stresses, leading to the big white plume of water vapor. The shuttle was torn apart shortly thereafter from similar aerodynamic stresses.
Both SRBs - even the one with fire belching out of the lower O-ring - can be seen in video of the disaster as flying onwards, well away from the conflagration, relatively unscathed. They were eventually blown up by range control officers.
The root cause of the failure cascade was indeed a problem with the SRB, things did go to hell all of a sudden in a rather spectacular way, and it certainly sucked to be them.
But technically, the SRBs themselves didn't fail catastrophically. Anyone lucky (?) enough to have been riding along in the nose cone of the SRB along with the SRB parachutes (let's assume the presence of suitable breathing apparatus since it's probably not pressurized, the presence of sound/vibrationproofing, temperature control, and of course, a nice parachute for our intrepid stowaway) would have had pretty good odds compared to the Challenger crew... well, at least until range control blew up the SRBs.
Actually it does matter how the Challenger failed. It matters because the issue being discussed is whether or not sitting a crew on top of a SSB passes the safety standard that NASA is using. The GGP claimed the Challenger disaster was due to a SSB failure, and the GP corrected him.
If you read the GP again you'll see that he is pointing out that while SSBs have terrible failure modes, the probability of reaching those modes is lower. In any risk analysis it is important to quantify the probability of a complete failure, as well as the impact.
Give than an SSB is essentially a giant firework, which once lit the only thing to do is either a) retreat to a safe distance (ground staff) or b) pray (crew), it is saying something that the overall safety could be higher than the shuttle. But the shuttle takes the same dangerous SSBs and adds millions of complex parts with non-zero probabilities of failure.
While you have a point about redesigning the rocket until the escape system does work, and for a commercial transport system this would be essential, you seem to be missing something vital. Launch vehicles like this are at the limit of our current technology and engineering skills. We may have to settle for making them work at all, rather than extra niceties such as safety. Given the huge amounts of energy required to reach space, and that currently the only options that we have are detonating vast quantities of explosives slowly... there is a limit to how safe we can make this.
I don't usually reply to inflammatory posts, but it's modded +4 Informative right now and I don't have mod points.
First off, Air Force scientists may be very good, but the fact they gave you a fellowship is hardly supporting evidence. Second, just because someone has a degree from a better university doesn't mean they're more qualified for a promotion. Also, the fact that you posted as an AC and use phrases like "typical ghetto high school" makes me suspect you're not the elite DOD researcher you claim to be.
Maybe the Air Force is a color-blind, apolitical organization and NASA's just a bunch of inept liberals, but this reads more like a rant than a compelling argument.
From Oxford American Dictionaries: "affirmative action noun an action or policy favoring those who tend to suffer from discrimination, esp. in relation to employment or education; positive discrimination."
They are not talking about some dumbmass SSgt E-5 cook that, as you say "get above 40% on a nearly open-book history test and time served". He is referring to the civilian scientists and engineering officers in the test, development and design as well as range safety officers. It seems YOU are the idiot.
The Range Safety Officer can't let it just crash back to the ground. The stark reality is that in the event of a guidance failure the RSO's job is to activate the destruct system. Although the lives of the astronauts might be lost, the lives of hundreds of people on the ground take precedence. And no, there isn't really going to be time to determine which way the rocket is going. In the time it would take to figure that out, Cocoa Beach could be a flaming inferno.
The specifics of this issue aside(since I know next to nothing about modeling solid fuel rocket explosions, and two experts appear to disagree, along with a snide comment from a commercial outfit that would probably like the contract for themselves), what sort of safety should we bother shooting for with launch systems?
Obviously, if we have the choice between a more safe and a less safe system we should, all else being equal, chose the more safe one. However, all else is rarely equal. More safety likely adds weight, design time, cost, whatever. How much safety is worth adding, before we get to the "For fuck's sake, dude, garbage collectors die on the job at twice the rate, and being crushed in a dumpster isn't exactly a blaze of glory..." point and live with the risks?
Is there some direct assertion to be made(astronauts should suffer no more than X risk, period)? Should we take an empirical look at the risks of various occupations, and peg the acceptable astronaut risk as equal to that of some similar occupation for which an empirical actual risk value is available? Should we accept very high risks; because astronauts are highly likely to be well informed volunteers who have plenty of life alternatives?
Pushing for perfect is chasing a dream. Deciding what we should be aiming for seems much more relevant.
Hard to say. Page 16 of this [bls.gov] gives the occupational fatality rate for American garbage collectors in 2007(22.8 per 100,000 for anybody who doesn't feel like opening the PDF). That doesn't tell us who was at fault in those incidents, or whether poor safety equipment was involved.
I suspect that most of the risk is being hit by vehicles trying to pass the garbage truck while it is stopped to collect refuse(googling around didn't bring up a definitive justification for this, just references to a "University of Miami study" that said so). Adding, and enforcing, those little no passing signs, as they do for school buses, would presumably cut this down, at the expense of significant travel delays.
How much risk is acceptable? Is the Air Force suggesting that space exloration should be 0% risk, or less?
If so, then we should probably ground all aircraft, scrap all automobiles - you get the idea.
Let's face it. Sitting on top of tons of explosive, and lighting them off, is going to be risky. Minimize the risk, yeah, but there will always BE RISK. It doesn't matter what kind of engine you are using, or what kind of fuel it is using. A crash within the first minute of flight is often quite deadly in aviation simply because the pilot has so few options for ditching or bailing out. The same will always be true of spaceflight.
If we want 0% risk, we had better get started on that space elevator. Of course, there may be some hidden risk at some point in that ascent - but at least we won't be blowing it up to use it.
The Air Force doesn't seem to be making a moral judgment.
They're doing what any good scientist or engineer will do: "If you do this, this will happen. I'm not telling you what you *should* do, but simply what will happen if you do it."
Also, it helps to understand the AF's perspective here. As safety officers, they may have to be the ones pushing the Big Red Button (TM) if things go wrong. They're just laying things out so NASA knows what to expect. And as others have pointed out, "aborting" a solid rocket launch is... well... about as successful as aborting a nuclear reaction. You don't get to stop things from burning like you might with a liquid-fueled rocket. You just get to watch the remaining fuel get burned up, people on top or not.
"Welcome to NASA. We're going to send you into space, but this involves sitting you atop something that's basically a big stick of explosives. We're aiming for a controlled burn, and most of the time we get that part right, but as you're probably aware, every now and then something does blow the heck up.
Now, as you might imagine, if you are sitting atop a big stick of explosives, and it blows the heck up, you probably go with it. We're going to try to give you some kind of an out so that the explosives can blow up without you doing the same, but we want you to know it's not really going to make your odds all that much better."
I mean, seriously, folks. People don't sign up to be astronauts without grasping that there's a very real risk of death at pretty much every point in the mission.
"But Jeff Hanley, who manages NASA's Constellation program that includes the Ares I, questioned the validity of the Air Force study because it relied on only one example. He said NASA had done its own study, using supercomputers to replicate the behavior of Ares I, that predicted a safe outcome."
Allow me to translate this:
"[...] He said NASA had done its own study, *USING NO EXAMPLES AT ALL WHATSOEVER*, that predicted the results that NASA required for further funding."
Show me that 'the supercomputers' model the Air Force's one example to within.5% of reality and I will consider apologizing to Mr. Hanley.
I am incredibly passionate about space flight. The incompetence and political gaming which has produced the fiasco that is the Ares has not caused me any surprise. From the moment NASA decided on solids for a manned vehicle I knew that, without question, the advancement of the state of the art was not going to come from NASA. Ares isn't about space travel. It's about government subsidies to existing aerospace contractors. Thiokol/ATK, I'm looking at you.
"NASA management has stated that their computer models predict a safe outcome."
-In retrospect, NASA also predicted the safe outcome of the last Challenger launch.
"It's time they you take off your Engineering hats and start putting on your Management hats."
- Famous last words. Unfortunately, with the current disagreement brewing, I think someone at NASA must have uttered those very same words, not knowing what trouble they can cause.
Correct me if I'm wrong, but I think NASA has all the elements for the Perfect Storm:
1. Underfunded, 2. Overzealous and overbearing management, 3. Overconfidence, 4. Massively complex, high-risk mechanical systems, 5. Career managers making critical decisions, instead of career engineers, 6. Over-valued managers, 7. Under-valued engineers.
Ever notice how when something goes wrong at NASA, it almost always results in a massive, explosive failure, along with several deaths?
Oh well. This conflict will give the networks something to scruitinze instead of endless "specials" on the life and death of some freaky-deeky nutjob pop singer.
This is only the latest in a long line of technical problems with Ares I, to say nothing of all the delays, cost overruns and other management issues.
First [spaceref.com], they discovered an oscillation issue from the SRB that could cause damage to the upper stage and the orion capsule. Last year [discovermagazine.com], they found out that with a slight wind gust, the vehicle might collide with its launch tower.
Incidentally, both of these problems and the current one are all related to the SRB. President Obama needs to do the right thing here and kill Ares I before it has the chance to kill anyone.
To be fair, the survival rate of exploding space shuttles is currently 0% as well... At least the Ares as a mechanism to even allow for an early abort.
The survival rate for exploding Soyuz rockets is 100%. It happened once in 1975, and again in 1983. Both times, the crew escaped without major injury. The Russian/Soviet space program has never had a launch failure that resulted in fatalities to crew aboard the ship.
The 1983 incident occurred as the rocket exploded while on the pad, and threw the capsule 6,500 feet into the air, subjecting the cosmonauts to approximately 17g of acceleration. According to popular legend, the cosmonauts destroyed the capsule's voice recorder due to the lengthy string of profanity that it captured during the incident.
The rocket that exploded to cause the Nedelin disaster was an ICBM -- strictly speaking, not even part of the space program.
Additionally, the Russian space program had notable problems with re-entry, safety on the ground, automated docking, off-target landings, or the fact that they couldn't get the N-1 to work at all.
However, we're not talking about any of these things. Russia's launch abort system has proven itself to be successful, and has saved lives in two separate incidents. Although NASA has certainly done a better job of other aspects of its program, its launch abort system has never been used in practice and is conspicuously absent from the shuttle, which is the entire point of this conversation.
Odds are that both uses of the Russian launch abort system could have been avoided by correcting deficiencies present elsewhere in their space program. However, it's certainly nice to have redundancies present in the system. Shuttle missions have to be conducted with outright paranoia due to some of its design deficiencies.
Oddly enough that regime was so fond of paperwork that there were weird documents along the lines of "order to destroy all records of the mass graves at lat X long Y containing Z bodies from the incident on DATE" with all the correct numbers filled in. People were so careful to cover their arses that everything was written down (even attempts to duplicate things that had been ordered destroyed) and is now a goldmine for historians. However there is still the garbage in garbage out problem if the information was wrong in the first place.
To be fair, the survival rate of exploding space shuttles is currently 0% as well... At least the Ares as a mechanism to even allow for an early abort.
Allow me to present a little bit more context. Back in 2004, NASA received several competing designs for lunar launch architectures, most/all of which involved using liquid-fueled EELV rockets. In 2005 the (now former) administrator Michael Griffin came in, tossed out all the EELV-based designs, and focused the agency on implementing his own solid-rocket design which eventually became the Ares I. A big part of the justification is that the EELV-based designs would have "black zones" during which a rocket failure would be non-survivable, while the Ares I supposedly had no such black zones and was therefore the only legitimate solution. Ironically, since that time the EELVs have been shown to have no such 'black zones," while this latest report indicates that the Ares I has a huge black zone which covers the entire first minute of flight. That means that what was thought to be the main justification for the Ares I is actually a huge deficiency.
Curiously, the other main justifications for the Ares I were that it would be finished faster and cost less than EELV-based designs. As it turned out, it's taking far longer than the EELVs were expected to take, and the cost has ballooned by almost an order of magnitude. With any luck Barack Obama will take the upcoming report from the Augustine Commission and end the Ares I program before it does any more damage.
You mean a Bush appointee came in and went ahead with a plan of action based on a false set of data and discarded all alternatives due to some theoretical, but now disproven, threat to American lives? You don't say...
Oh please, you can't compare the missed milestones of one program against another program that never missed a milestone because it never started.
Actually, since the other designs used already-existing EELV rockets, there were essentially quite a few milestones already finished.
As for the safety argument, IMHO it's so hypothetical I don't even care. I still don't think anybody knows how safe the shuttle now is, or isn't.
Yeah... it's also kind of interesting how the supposedly safer "man-rated" systems seem to have a pretty similar failure rate to the non-man-rated launch vehicles. IMHO, the only way you can really get a good idea of the safety of a system is through repeated unmanned testing, which coincidentally the EELVs have quite a few flights worth of already.
However, if costs on a program have actually exceeded plans by a factor of 10, I think you have a good argument for developing both in parallel in a big programmatic deathmatch.
Coincidentally, this was pretty much what the original plan was back in 2004: The top two design proposal teams (one headed by Lockheed Martin, the other headed by Northrop Grumman and Boeing) would receive initial funding of $1 billion and compete against each other in an unmanned "fly-off" test of their EELV-based in 2008. Former administrator Michael Griffin was convinced his design was safer/better/faster though, so he tossed out the existing designs (and the whole idea of competitive parallel development) and focused NASA on his Ares I.
I worked at Marshall Space Flight Center -- the facility where the Ares is being developed -- for a while as part of an undergrad summer research project. While it may not be polite to say such things, AC's criticism of NASA's affirmative action policies is spot on.
My boss and his officemate were both affirmative action hires. My boss couldn't remember his computer password and called IT every time he crashed WinNT and needed to reboot. His officemate just put his on a stickynote on his monitor. When he got a new computer he had to get me (an undergrad) to make him a desktop shortcut to Solitaire. I have no idea what that guy did other than order office supplies.
My boss often skipped work to play golf, leaving me in charge of the lab. I wound up growing samples in a gas deposition chamber and giving them to him to catalog and characterize. At one point I asked him how the characterization was going, and he said that the Raman spectroscopy lab was buried under a backlog of debris from Columbia (which was earlier that year). At the end of the summer I had a chat with *his* boss, who told me that there was no such backlog... and then we found all the samples I had painstakingly grown and labelled lying jumbled in the bottom of a drawer of his.
While it makes me sad to say it, I've seen Marshall Space Flight Center incompetence with my own eyes. I'm from Huntsville, the city where MSFC is located. When I was growing up Real Science got done there -- my high school English teacher is the guy who built the Lunar Rover. But it's gone downhill.
I also know the guy who's in charge of systems integration for the Ares project. He's a young-earth creationist. I have little faith in the engineering acumen of anyone who can accomplish such a massive feat of ignoring experimental evidence.
I also know the guy who's in charge of systems integration for the Ares project. He's a young-earth creationist. I have little faith in the engineering acumen of anyone who can accomplish such a massive feat of ignoring experimental evidence.
Have you considered asking him how he reconciles the two habits of mind?
Especially for a German. He designed the thing, wound up retiring from NASA, and teaching English in his German accent.
Guy had quite the sense of humor, along with a reputation for being hard as hell. I asked him in the halls one day how many people had dropped dead from his latest exam, and he said "Oh, all of them! I run a mortuary on the side; good way to get more business!"
It takes a modern computer far less than six days to computationally model the behavior of the large belt of asteroids between Mars and Jupiter using Newton's law of gravitation.
If you do that, you'll see large gaps ("Kirkwood gaps") develop at radii corresponding to orbital resonances with Jupiter. These gaps take far more than six thousand years to develop.
If you look at the asteroid belt, such gaps actually exist. If the Universe is six thousand years, how did they get there? (No credit for "The universe is young but God wanted it to look old".)
***
There are celestial bodies far in excess of six thousand light years away. Anyone building spacecraft surely ought to know about them.
Then there's the georadiological evidence that I'm not going to go into because it's less applicable to astronomy.
I'd be surprised if any manned launch system up to now would allow the crew to survive under the condtions specified. Apollo? Apollo 1 killed its crew before even getting off the ground. Probably back then it was better understood by the public that space travel is crazy dangerous.
Some things are not worth solving. We are talking a 1 minute window of issues. With Ares I already at the max load, it makes no sense to add more weight for the escape rocket. That is just part of the risk of being an astronaut.
The Russian and us, sans 40 years of "experience." You'd think Challenger would've taught us something about stackable SRBs and people. Or Columbia something about non-melting crew return vehicles.
Oh, I just had an idea! How about a capsule with an ablative heat shield mounted on top of a liquid-fueled, multi-stage heavy lifter?! I know, I know, I'm a genius (and a rocket scientist, IRL, coincidentally).
It's amazing that after the Mercury, Gemini, and Apollo successes we can't seem to figure out how to make heavy lift rockets. This is nearly 40 years after Apollo was canceled
(Emphasis mine.) You have your own answer. Apollo came after Gemini, which came after Mercury, all in a single decade. And several years of NASA unmanned (though occasionally monkeyed) flights before that. A decade of various missile work before that. And a decade of prior smaller scale work each by Goddard & co and the Naz^H^H^HGermans before that. Every guy working on Apollo had years of prior experience blowing up rockets, senior guys decades.
Since Apollo, you had skylab. A one-off bit of throw away kit. Then a ten year wait after Apollo for the shuttle. Then "Freedom", a 20+ year long program downgraded to the ISS around a Russian core. 20 years, to deliver a single station.
Then, over 20 years since the newest shuttle was built, we have Constellation - Ares & Orion. No incremental development, no learning their "craft", just one design, refusing all criticism, and fuck you if it's wrong.
(And Ares I isn't a first step, it's the first half of a single program. It isn't a training run, it isn't allowed to go wrong.)
NASA's problems aren't lack of either funding or some mythical "Vision" or Kennedyesque "Challenge", nor is it political interference; it's lack of experience. Noone who has been working at NASA&co less than 20 years has been involved with the development of a manned launcher. Not one. Not the designers, the managers who chose that design, not the engineers working on it.
I don't care how high their IQ's, how many PhD's per square mile they have, you cannot expect them to succeed without giving them a chance to build real hardware for ten years, real rockets, real capsules, before they design your final project.
Women are more easily and more deeply terrified ... generating more
sheer horror than the male of the species.
-- Spock, "Wolf in the Fold", stardate 3615.4
100% (Score:5, Insightful)
Spaceflight was so much easier forty years ago...
The same NASA (Score:5, Insightful)
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Re:100% (Score:5, Insightful)
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It shouldn't be dangerous! (Score:4, Insightful)
Space flight needs to get to the stage where it is not dangerous. It should be routine and boring and reliable.
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Re:It shouldn't be dangerous! (Score:4, Insightful)
Because we all know how no one gets hurt while driving a car. Or just walking during winter.
No, but we have made these activities safe enough that they are routine, boring and reliable.
There is no such thing as 100% safe. The only way to guarantee not being hurt by a car, for example, is to avoid them completely. That would be ridiculous.
My point is that NASA doesn't seem to be taking safety seriously enough. Political considerations seem to be more important to them. NASA should be making steps forwards in safety. To do otherwise is simply crazy and morally wrong.
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Re:It shouldn't be dangerous! (Score:5, Insightful)
We don't know how to make it safe or routine yet. In my mind, that's justification to spend the money and figure it out. Unfortunately, too many people think high-efficiency engines, advanced lightweight structures, and durable thermal protection systems just materialize from thin air at some unspecified date in the future, and therefore we should just sit back and do nothing till they appear.
It doesn't work like that. Reliable, cheap space access doesn't just happen. You need to work on it first, and too many don't understand that.
Imagine if, in 1909, the world had collectively decided to stop building new airplanes and just wait until something like the 747 came along. We sure wouldn't have reliable aviation.
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IANARS but... (Score:5, Insightful)
If I'm reading this right, the Air Force is saying that in the event of a complete failure (ie, the entire thing going to hell all of a sudden) the chances of survival would be zero.
This doesn't really indicate that chances of survival would be zero in all possible emergency abort scenarios.
Re:IANARS but... (Score:5, Insightful)
Solid rocket motors, however, tend to "go to hell all of a sudden" in a rather spectacular way. "Sucks to be you" is really their only failure mode.
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Re:IANARS but... (Score:5, Informative)
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Re:IANARS but... (Score:5, Interesting)
Fortunately it seems like this is a problem that *could be corrected* fairly easily -- with, say, a propulsion mechanism on the escape capsule, just enough to give enough delta-V that it would clear the debris cloud in time to deploy the parachutes.
From what I understand, the Orion capsule's launch escape system already has a jettison motor [nasa.gov], but it's not enough to take it out of range of the flaming debris. Increasing the range of the motor isn't an option, because the capsule is already too heavy for the Ares I and they can't add even more weight to it.
Even though rockets like DIRECT's and the Ares V would have the "field of flaming solid rocket propellant debris" problem, my impression is that they have a big enough margin that you'd be able to have a launch escape system that could escape the debris cloud.
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Re:IANARS but... (Score:5, Insightful)
I am a rocket scientist. The Orion does have an escape motor. And outside of the range specified in the briefing it gets it safely away from the SRB propellant. The problem is due to it being a solid propellant booster, when you decide to get out of Dodge, you only have three choices: Blow up the SRB at the same time, blow it up shortly after the escape motor lights, or don't blow it up at all. For public safety and some other reasons, #3 is not acceptable. #1 is not acceptable because now you're always going to have flaming debris around the capsule. So #2 is the solution with the detail being how long of a delay. NASA's simulation have determined the most optimal time delay, for their purposes. The Air Force has agreed with that value. But that delay is the time the SRB keeps following the capsule. And it's still accelerating. And it's accelerating faster because it no longer has to push the capsule. This is a problem that can occur with ANY solid propellant choice, so the Direct crowd and NASA's shuttle alternative may also have this potential problem. Only a purely liquid propellant vehicle that could be shutdown immediately on activating of the escape motor could avoid this problem.
From the Air Force's point of view, this would not affect Ares' launch as long as the flight termination system works--Air Force is responsible for public safety, not the astronauts, that's NASA responsibility. Air Force sent their analysis to NASA, NASA (someone at NASA) made it public.
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Re:IANARS but... (Score:5, Interesting)
Nitpick: The Challenger SRBs were fine. The external tank failed.
The SRBs leaked a bit of fire through the O-ring, and that fire meant that one of the SRBs cut itself away from the external tank - the attachment at the bottom of the tank failed, the one at the top didn't, and that was enough to plow the nose of the SRB into the tip of the external tank.
*boom*
The external tank tore itself apart from the aerodynamic stresses, leading to the big white plume of water vapor. The shuttle was torn apart shortly thereafter from similar aerodynamic stresses.
Both SRBs - even the one with fire belching out of the lower O-ring - can be seen in video of the disaster as flying onwards, well away from the conflagration, relatively unscathed. They were eventually blown up by range control officers.
The root cause of the failure cascade was indeed a problem with the SRB, things did go to hell all of a sudden in a rather spectacular way, and it certainly sucked to be them.
But technically, the SRBs themselves didn't fail catastrophically. Anyone lucky (?) enough to have been riding along in the nose cone of the SRB along with the SRB parachutes (let's assume the presence of suitable breathing apparatus since it's probably not pressurized, the presence of sound/vibrationproofing, temperature control, and of course, a nice parachute for our intrepid stowaway) would have had pretty good odds compared to the Challenger crew... well, at least until range control blew up the SRBs.
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Re:IANARS but... (Score:5, Interesting)
Actually it does matter how the Challenger failed. It matters because the issue being discussed is whether or not sitting a crew on top of a SSB passes the safety standard that NASA is using. The GGP claimed the Challenger disaster was due to a SSB failure, and the GP corrected him.
If you read the GP again you'll see that he is pointing out that while SSBs have terrible failure modes, the probability of reaching those modes is lower. In any risk analysis it is important to quantify the probability of a complete failure, as well as the impact.
Give than an SSB is essentially a giant firework, which once lit the only thing to do is either a) retreat to a safe distance (ground staff) or b) pray (crew), it is saying something that the overall safety could be higher than the shuttle. But the shuttle takes the same dangerous SSBs and adds millions of complex parts with non-zero probabilities of failure.
While you have a point about redesigning the rocket until the escape system does work, and for a commercial transport system this would be essential, you seem to be missing something vital. Launch vehicles like this are at the limit of our current technology and engineering skills. We may have to settle for making them work at all, rather than extra niceties such as safety. Given the huge amounts of energy required to reach space, and that currently the only options that we have are detonating vast quantities of explosives slowly... there is a limit to how safe we can make this.
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Re:IANARS but... (Score:5, Insightful)
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Re:The Air Force is right. (Score:4, Informative)
The armed services ... promote solely on the basis of merit.
As a former member of the armed services, I find that hilarious.
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Re:The Air Force is right. (Score:4, Insightful)
First off, Air Force scientists may be very good, but the fact they gave you a fellowship is hardly supporting evidence. Second, just because someone has a degree from a better university doesn't mean they're more qualified for a promotion. Also, the fact that you posted as an AC and use phrases like "typical ghetto high school" makes me suspect you're not the elite DOD researcher you claim to be.
Maybe the Air Force is a color-blind, apolitical organization and NASA's just a bunch of inept liberals, but this reads more like a rant than a compelling argument.
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Re:The Air Force is right. (Score:4, Insightful)
>Racist much?
From Oxford American Dictionaries:
"affirmative action
noun
an action or policy favoring those who tend to suffer from discrimination, esp. in relation to employment or education; positive discrimination."
Yes. Yes it is.
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Re:The Air Force is right. (Score:4, Informative)
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Re:IANARS but... (Score:5, Informative)
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More Broadly... (Score:5, Insightful)
Obviously, if we have the choice between a more safe and a less safe system we should, all else being equal, chose the more safe one. However, all else is rarely equal. More safety likely adds weight, design time, cost, whatever. How much safety is worth adding, before we get to the "For fuck's sake, dude, garbage collectors die on the job at twice the rate, and being crushed in a dumpster isn't exactly a blaze of glory..." point and live with the risks?
Is there some direct assertion to be made(astronauts should suffer no more than X risk, period)? Should we take an empirical look at the risks of various occupations, and peg the acceptable astronaut risk as equal to that of some similar occupation for which an empirical actual risk value is available? Should we accept very high risks; because astronauts are highly likely to be well informed volunteers who have plenty of life alternatives?
Pushing for perfect is chasing a dream. Deciding what we should be aiming for seems much more relevant.
Re:More Broadly... (Score:4, Interesting)
I suspect that most of the risk is being hit by vehicles trying to pass the garbage truck while it is stopped to collect refuse(googling around didn't bring up a definitive justification for this, just references to a "University of Miami study" that said so). Adding, and enforcing, those little no passing signs, as they do for school buses, would presumably cut this down, at the expense of significant travel delays.
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Risk? (Score:5, Interesting)
How much risk is acceptable? Is the Air Force suggesting that space exloration should be 0% risk, or less?
If so, then we should probably ground all aircraft, scrap all automobiles - you get the idea.
Let's face it. Sitting on top of tons of explosive, and lighting them off, is going to be risky. Minimize the risk, yeah, but there will always BE RISK. It doesn't matter what kind of engine you are using, or what kind of fuel it is using. A crash within the first minute of flight is often quite deadly in aviation simply because the pilot has so few options for ditching or bailing out. The same will always be true of spaceflight.
If we want 0% risk, we had better get started on that space elevator. Of course, there may be some hidden risk at some point in that ascent - but at least we won't be blowing it up to use it.
Re:Risk? (Score:5, Insightful)
The Air Force doesn't seem to be making a moral judgment.
They're doing what any good scientist or engineer will do: "If you do this, this will happen. I'm not telling you what you *should* do, but simply what will happen if you do it."
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Re:Risk? (Score:4, Informative)
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Maybe it's just an occupational hazard. (Score:5, Insightful)
Here's the straight-talk version:
"Welcome to NASA. We're going to send you into space, but this involves sitting you atop something that's basically a big stick of explosives. We're aiming for a controlled burn, and most of the time we get that part right, but as you're probably aware, every now and then something does blow the heck up.
Now, as you might imagine, if you are sitting atop a big stick of explosives, and it blows the heck up, you probably go with it. We're going to try to give you some kind of an out so that the explosives can blow up without you doing the same, but we want you to know it's not really going to make your odds all that much better."
I mean, seriously, folks. People don't sign up to be astronauts without grasping that there's a very real risk of death at pretty much every point in the mission.
Made up data Real life ( Wait. What? ) (Score:5, Insightful)
"But Jeff Hanley, who manages NASA's Constellation program that includes the Ares I, questioned the validity of the Air Force study because it relied on only one example. He said NASA had done its own study, using supercomputers to replicate the behavior of Ares I, that predicted a safe outcome."
Allow me to translate this:
"[...] He said NASA had done its own study, *USING NO EXAMPLES AT ALL WHATSOEVER*, that predicted the results that NASA required for further funding."
Show me that 'the supercomputers' model the Air Force's one example to within
I am incredibly passionate about space flight. The incompetence and political gaming which has produced the fiasco that is the Ares has not caused me any surprise. From the moment NASA decided on solids for a manned vehicle I knew that, without question, the advancement of the state of the art was not going to come from NASA. Ares isn't about space travel. It's about government subsidies to existing aerospace contractors. Thiokol
Wait For The Bang..... (Score:4, Insightful)
"NASA management has stated that their computer models predict a safe outcome."
-In retrospect, NASA also predicted the safe outcome of the last Challenger launch.
"It's time they you take off your Engineering hats and start putting on your Management hats."
- Famous last words. Unfortunately, with the current disagreement brewing, I think someone at NASA must have uttered those very same words, not knowing what trouble they can cause.
Correct me if I'm wrong, but I think NASA has all the elements for the Perfect Storm:
1. Underfunded,
2. Overzealous and overbearing management,
3. Overconfidence,
4. Massively complex, high-risk mechanical systems,
5. Career managers making critical decisions, instead of career engineers,
6. Over-valued managers,
7. Under-valued engineers.
Ever notice how when something goes wrong at NASA, it almost always results in a massive, explosive failure, along with several deaths?
Oh well. This conflict will give the networks something to scruitinze instead of endless "specials" on the life and death of some freaky-deeky nutjob pop singer.
This isn't the only technical problem with Ares I (Score:4, Informative)
First [spaceref.com], they discovered an oscillation issue from the SRB that could cause damage to the upper stage and the orion capsule. Last year [discovermagazine.com], they found out that with a slight wind gust, the vehicle might collide with its launch tower.
Incidentally, both of these problems and the current one are all related to the SRB. President Obama needs to do the right thing here and kill Ares I before it has the chance to kill anyone.
Re:Badass (Score:4, Funny)
They have a burning commitment to the program.
As in, "the Chef is concerned, but the Chicken is committed." :-)
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Re:100%? (Score:5, Informative)
To be fair, the survival rate of exploding space shuttles is currently 0% as well... At least the Ares as a mechanism to even allow for an early abort.
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Re:100%? (Score:5, Interesting)
The survival rate for exploding Soyuz rockets is 100%. It happened once in 1975, and again in 1983. Both times, the crew escaped without major injury. The Russian/Soviet space program has never had a launch failure that resulted in fatalities to crew aboard the ship.
The 1983 incident occurred as the rocket exploded while on the pad, and threw the capsule 6,500 feet into the air, subjecting the cosmonauts to approximately 17g of acceleration. According to popular legend, the cosmonauts destroyed the capsule's voice recorder due to the lengthy string of profanity that it captured during the incident.
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Re:100%? (Score:4, Funny)
Only Russians could swear while undergoing 17 g acceleration.
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Re:100%? (Score:4, Informative)
Without that last qualification things get a little hairier [wikipedia.org].
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Re:100%? (Score:4, Interesting)
The rocket that exploded to cause the Nedelin disaster was an ICBM -- strictly speaking, not even part of the space program.
Additionally, the Russian space program had notable problems with re-entry, safety on the ground, automated docking, off-target landings, or the fact that they couldn't get the N-1 to work at all.
However, we're not talking about any of these things. Russia's launch abort system has proven itself to be successful, and has saved lives in two separate incidents. Although NASA has certainly done a better job of other aspects of its program, its launch abort system has never been used in practice and is conspicuously absent from the shuttle, which is the entire point of this conversation.
Odds are that both uses of the Russian launch abort system could have been avoided by correcting deficiencies present elsewhere in their space program. However, it's certainly nice to have redundancies present in the system. Shuttle missions have to be conducted with outright paranoia due to some of its design deficiencies.
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Re:100%? (Score:5, Interesting)
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Re:100%? (Score:4, Informative)
It wasn't the explosion that killed the Challenger astronauts but impact with the sea. [wikipedia.org]
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Re:100%? (Score:5, Informative)
To be fair, the survival rate of exploding space shuttles is currently 0% as well... At least the Ares as a mechanism to even allow for an early abort.
Allow me to present a little bit more context. Back in 2004, NASA received several competing designs for lunar launch architectures, most/all of which involved using liquid-fueled EELV rockets. In 2005 the (now former) administrator Michael Griffin came in, tossed out all the EELV-based designs, and focused the agency on implementing his own solid-rocket design which eventually became the Ares I. A big part of the justification is that the EELV-based designs would have "black zones" during which a rocket failure would be non-survivable, while the Ares I supposedly had no such black zones and was therefore the only legitimate solution. Ironically, since that time the EELVs have been shown to have no such 'black zones," while this latest report indicates that the Ares I has a huge black zone which covers the entire first minute of flight. That means that what was thought to be the main justification for the Ares I is actually a huge deficiency.
Curiously, the other main justifications for the Ares I were that it would be finished faster and cost less than EELV-based designs. As it turned out, it's taking far longer than the EELVs were expected to take, and the cost has ballooned by almost an order of magnitude. With any luck Barack Obama will take the upcoming report from the Augustine Commission and end the Ares I program before it does any more damage.
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Re:100%? (Score:5, Funny)
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Re:100%? (Score:4, Informative)
Oh please, you can't compare the missed milestones of one program against another program that never missed a milestone because it never started.
Actually, since the other designs used already-existing EELV rockets, there were essentially quite a few milestones already finished.
As for the safety argument, IMHO it's so hypothetical I don't even care. I still don't think anybody knows how safe the shuttle now is, or isn't.
Yeah... it's also kind of interesting how the supposedly safer "man-rated" systems seem to have a pretty similar failure rate to the non-man-rated launch vehicles. IMHO, the only way you can really get a good idea of the safety of a system is through repeated unmanned testing, which coincidentally the EELVs have quite a few flights worth of already.
However, if costs on a program have actually exceeded plans by a factor of 10, I think you have a good argument for developing both in parallel in a big programmatic deathmatch.
Coincidentally, this was pretty much what the original plan was back in 2004: The top two design proposal teams (one headed by Lockheed Martin, the other headed by Northrop Grumman and Boeing) would receive initial funding of $1 billion and compete against each other in an unmanned "fly-off" test of their EELV-based in 2008. Former administrator Michael Griffin was convinced his design was safer/better/faster though, so he tossed out the existing designs (and the whole idea of competitive parallel development) and focused NASA on his Ares I.
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Re:The Air Force is right. (Score:5, Interesting)
I worked at Marshall Space Flight Center -- the facility where the Ares is being developed -- for a while as part of an undergrad summer research project. While it may not be polite to say such things, AC's criticism of NASA's affirmative action policies is spot on.
My boss and his officemate were both affirmative action hires. My boss couldn't remember his computer password and called IT every time he crashed WinNT and needed to reboot. His officemate just put his on a stickynote on his monitor. When he got a new computer he had to get me (an undergrad) to make him a desktop shortcut to Solitaire. I have no idea what that guy did other than order office supplies.
My boss often skipped work to play golf, leaving me in charge of the lab. I wound up growing samples in a gas deposition chamber and giving them to him to catalog and characterize. At one point I asked him how the characterization was going, and he said that the Raman spectroscopy lab was buried under a backlog of debris from Columbia (which was earlier that year). At the end of the summer I had a chat with *his* boss, who told me that there was no such backlog... and then we found all the samples I had painstakingly grown and labelled lying jumbled in the bottom of a drawer of his.
While it makes me sad to say it, I've seen Marshall Space Flight Center incompetence with my own eyes. I'm from Huntsville, the city where MSFC is located. When I was growing up Real Science got done there -- my high school English teacher is the guy who built the Lunar Rover. But it's gone downhill.
I also know the guy who's in charge of systems integration for the Ares project. He's a young-earth creationist. I have little faith in the engineering acumen of anyone who can accomplish such a massive feat of ignoring experimental evidence.
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Re:The Air Force is right. (Score:5, Insightful)
Have you considered asking him how he reconciles the two habits of mind?
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Re:The Air Force is right. (Score:5, Funny)
Especially for a German. He designed the thing, wound up retiring from NASA, and teaching English in his German accent.
Guy had quite the sense of humor, along with a reputation for being hard as hell. I asked him in the halls one day how many people had dropped dead from his latest exam, and he said "Oh, all of them! I run a mortuary on the side; good way to get more business!"
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Re:The Air Force is right. (Score:5, Informative)
It takes a modern computer far less than six days to computationally model the behavior of the large belt of asteroids between Mars and Jupiter using Newton's law of gravitation.
If you do that, you'll see large gaps ("Kirkwood gaps") develop at radii corresponding to orbital resonances with Jupiter. These gaps take far more than six thousand years to develop.
If you look at the asteroid belt, such gaps actually exist. If the Universe is six thousand years, how did they get there? (No credit for "The universe is young but God wanted it to look old".)
***
There are celestial bodies far in excess of six thousand light years away. Anyone building spacecraft surely ought to know about them.
Then there's the georadiological evidence that I'm not going to go into because it's less applicable to astronomy.
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Re:Ares Rocket less safe than a Space Shuttle? (Score:4, Informative)
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Re:Ares Rocket less safe than a Space Shuttle? (Score:4, Informative)
Soyuz. The rocket exploded twice, in 1975 and 1983, and each time the crew survived. See http://www.janes.com/aerospace/civil/news/jsd/jsd030203_3_n.shtml [janes.com]
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Re:Sometimes /. is so fatalistic (Score:4, Informative)
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Re:Sometimes /. is so fatalistic (Score:4, Insightful)
Rather than investing more in escape systems, it might make more sense to spend the same amount of money making rockets that blow up less...
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Re:Sometimes /. is so fatalistic (Score:4, Funny)
Of course, a solid steel parachute! Why didn't we think of this before!
Signed,
Ares Engineers
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Re:That's OK... (Score:4, Interesting)
The Russian and us, sans 40 years of "experience." You'd think Challenger would've taught us something about stackable SRBs and people. Or Columbia something about non-melting crew return vehicles.
Oh, I just had an idea! How about a capsule with an ablative heat shield mounted on top of a liquid-fueled, multi-stage heavy lifter?! I know, I know, I'm a genius (and a rocket scientist, IRL, coincidentally).
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Re:We used to be so good at this (Score:5, Insightful)
It's amazing that after the Mercury, Gemini, and Apollo successes we can't seem to figure out how to make heavy lift rockets. This is nearly 40 years after Apollo was canceled
(Emphasis mine.) You have your own answer. Apollo came after Gemini, which came after Mercury, all in a single decade. And several years of NASA unmanned (though occasionally monkeyed) flights before that. A decade of various missile work before that. And a decade of prior smaller scale work each by Goddard & co and the Naz^H^H^HGermans before that. Every guy working on Apollo had years of prior experience blowing up rockets, senior guys decades.
Since Apollo, you had skylab. A one-off bit of throw away kit. Then a ten year wait after Apollo for the shuttle. Then "Freedom", a 20+ year long program downgraded to the ISS around a Russian core. 20 years, to deliver a single station.
Then, over 20 years since the newest shuttle was built, we have Constellation - Ares & Orion. No incremental development, no learning their "craft", just one design, refusing all criticism, and fuck you if it's wrong.
(And Ares I isn't a first step, it's the first half of a single program. It isn't a training run, it isn't allowed to go wrong.)
NASA's problems aren't lack of either funding or some mythical "Vision" or Kennedyesque "Challenge", nor is it political interference; it's lack of experience. Noone who has been working at NASA&co less than 20 years has been involved with the development of a manned launcher. Not one. Not the designers, the managers who chose that design, not the engineers working on it.
I don't care how high their IQ's, how many PhD's per square mile they have, you cannot expect them to succeed without giving them a chance to build real hardware for ten years, real rockets, real capsules, before they design your final project.
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