ground-based telescopes (which had been used to inspect some earlier shuttles).
Those pictures had very poor resolution, so they were useless. This little bird takes pictures from a fe feet away. BIG difference!
You're suggesting that part of the ISS budget overruns are the launches themselves and not on-the-ground construction.
Sorry, I wasn't clear on that point. Sure, more launches cost more bucks. But there's something else involved.
Almost every ISS structure payload had to be redesigned since the high inclination orbits have lower max payload weights fo the shuttle. The missions (construction tasks) then also needed to be redesigned. In addition, since more trips were needed, the constuction sequence had to be strtched out. Once the station was manned, that also increased the consumeable supplies fraction that had to be brought up on every mission. Which further reduced payloads...
Beyond that, the existing Russian gear had to be integrated and qualified, and new Russian gear and proceures had to be worked out. And all this happened in the atmosphere of mistrust that followed the Cold War. Then there was the language thing, and the intercontinental / time zone problems.
The estimated budget kept going up. No surprise to me. Did anyone that forsee all those costs back in '88?
SSME turbine pump blades have been found to be a weakness in the SSME design that has yet to be dealt with adequately.
True at the time, but the problem has been addressed since then. That was 1988, this is now.
APU's have been found to be a weakness
idem dito
An "economical" launch system is what the military needs to launch its crushing backlog of spy satellites and Vandenburg is the only launch site which can make polar orbit without going over populated areas.
The EELV program delt with this problem. Look it up on Google. Beau Coups references. Also, DoD is moving to more small payloads, not ever larger ones...
The SSME bell is not being adequately inspected for hairline cracks which could fail catastrophically during launch.
Old news, delt with long ago...
NASA continues to invest more and more money
in SRB research to the exclusion of other areas of far greater weakness in the Shuttle system. Obviously, it will not invest adequate money in those areas...
NASA does a wide variety of research, though obviously not every project gets the funding that
you or I would like to see. Write your congressman if you know about "fluff" projects, or if you have one that you feel deserves funding. DARPA also funds projects, and is not shy about "High Risk/High Reward" bets.
In the real world, when you have a contract to do something and you end up going over budget, you have two options: Swallow the loss or swallow the loss. However, government contracts don't work that way. Contractors get to write clauses in the contracts that essentially say "If we go over budget, the government will pay us the difference." The original bids are nothing but ink on paper.
That's being a bit loose with the facts...
NASA continues to have a major say in ISS and Shuttle development. The contract is like that between a remodeler or a builder and the homeowner. You get the picture...
The station orbit choice, all by itself, was responsible for a huge cost increase. A high inclination orbit was chosen to bring the Ruskies on board. If the everyday folks in Russia couldn't look up and see the thing, they wouldn't think of it as their own, and they wouldn't give up MIR. Politics, plain and simple. Not good or bad, just politics.
BUT: High inclination orbits take more fuel to get to ==>> leads to ==>> less payload ==>> leads to ==>> more flights & redesign of heavy payloads ==>> leads to ==>> higher costs ($$$$).
I estimate (personal guess) that the high inclination orbit cost us something like 20% more $ per pound in orbit for ever pound for the lifetime of the ISS!!!!
Anyway, you get the picture, neither Boeing, nor NASA, are really "cheats or idiots". There is a cost associated with the "International" part of the ISS, and I'm glad we're paying it.
Yes, they probably confused the 70 degree angle of attack. The shuttle is very stable at that angle, and the flow is very smooth, so there's very little vibration.
The problem is that there's too much lift, and you want the thing to come down. So the S turns convert the lift vector into somewhat sideways vectors, which, because the rolls are reversed, cancel each other out over time. The track goes left and right, but you still are generally headed into KSC.
However, the flight is very smooth and gentle through the first couple of S turns, so that the tile surfaces aren't subjected to thermal shock, I believe.
Opinion: Something fell off, unbalanced the craft, and pinwheeled it at 12,500 MPH, at which point it simply tore apart.
Nothing has to "fall off". If the TPS tiles are damaged, then the hypersonic flow can experience a very large disturbance; standing shock waves result. Wherever they impinge on structure, temperatures rise immediately to much higher levels. For example, a shock from the leading edge of the wing could impinge on the side of the shuttle, the OMS pods, or the tail. This happened on one of the X-15 flights. The shock burned through most of the titanium tail in seconds. And this was at mach 5, not even a third of the orbiter speed!
The tiles probably were damaged on the left wing where the big chunk of ice hit at take off...
Ice hasn't disloged or damaged any tiles for some time now. The ice used to build up on the top of the external tank (ET), and was shed during the liftoff. Nowadays, there is a big cap over the external tank, and dry nitrogen gas is blown down over the ET nose, so no ice forms. On this launch, some of the foam insulation was shed. It isn't hard like ice; it's kind of light and foamy like a dry sponge. It could have done some damage, but not like the ice used to do. The ice used to damage the external tile surfaces of ceramic (white) tiles (not the back carbon/carbon tiles).
In addition, whole tiles used to come off because they weren't glued in place properly. This hasn't happened in the last 75 flights, because of an improved pull test, which yanks off the improperly glued tiles.
The final tile failure mode which has been fixed was this: water intruded into the joints between the tiles while the bird was on the pad (in rainstorms etc). The water flashed to steam during reentry (if memory serves) and that popped the tiles off. Improved seals between the tiles fixed that problem around the same time as the improved "pull test".
In spite of all these improvements, some problem needs to be found and fixed. Given the very low aerodynamic loads when it came over the coast (at 7:43) a chief suspect would be still have to be a failure of the Thermal Protection System (TPS), just as you say.
My condolences to all those who are grieving their loss. This loss shocks and disturbs me, and I want you to know that it took me about twenty years to recover from my own loss of a pilot friend in 1978. I hope that people will treat you gently. It might help you to understand the process which is unfolding now.
In general, the real experts refuse to speculate as to causes. You are best served by ignoring anyone who discusses causes without first laying out hard engineering evidence.
The general process we will now see is this:
1. Impound and secure all available data and have all involved parties (such as flight controllers) make notes on the events while they are still fresh in their minds.
2. Collect all debris, and note where each piece was found.
3. Start analysis, based on the known facts.
This is a case where the structure clearly broke up in flight. Because of this, the breakup sequence will be of great interest. It is usually determined by examining the pattern of the debris on the ground. In recent years, sophisticated analysis of radar returns have provided extraordinary insights into breakup sequences.
Telemetry from the shuttle (sent via the TDRS satellites) may also prove to be very valuable in this case. Shuttles are very well instrumented with sensors that show heating, structural stresses, control system inputs, and, of course, attitude, motions, and accelerations.
There is a blackout period for returning spacecraft, where they are enveloped by a plume of high temperature gas. The temperatures are high enough to strip electrons off, so the gas is a plasma which blocks radio transmissions. At this point, NASA is indicating that they were receiving telemetry, and that the loss of communication was the first (and prime) indicator of a mishap.
If memory serves, there are black box recorders on board shuttles: both a Cockpit Voice Recorder (CVR) and a Flight Data Recorder (CDR). It seems to me that Challenger CVR tape has never been made public, but makes for rather sobering listening. Don't expect the CVR to be made public. Many countries (such as Canada) forbid the public release of this type of recording.
My heart goes out to those of you who are suffering. Please feel free to contact me with complete privacy.
compare & contrast: p2p mp3 distro and what u
on
Ask Kevin Mitnick
·
· Score: 1
I hear you feel bad about what you did, but don't know what was OK, what was theft or whatever...
So is ripping a cd track, and shareing willy-nilly theft?
Social engineering sounds so impressive! Were u a con man?
cheers, man! put it behind u, move on, have fun, and take care!
isn't "a meeting of the minds" an essential aspect of a contract? I mean, an obviously intoxicated individual can't make a valid contract for this reason can he?
And aren't there exceptions made in contract law when the parties have "unequal strength", or some such thing?
I've often wondered whether all those strict and draconian terms are enforceable. I didn't realize that claiming enforceability might be regarded as consumer fraud. I like it!
NASA had two big successes: the moon program, and ICBM's (where they collaborated with DOD). NASA success depends on a common objective uniting everyone concerned - including Congress and the Administration de Jour...
I'd like to see a series of prizes for achievements.
Let Congress, or ESA, or private people pay into the prize pools. And of course, invest the money so that it's increasing all the time.
Possible prize-worthy achievements: (i)getting any single stage vehicle into orbit w/no throw-aways. (ii) getting a whole launch system back to earth and refurbishing it for reuse. (iii) finding water on the moon, and breaking it into H2 and O2. (Or doing the same on Mars.) Or...
MS is facing a judge and his judgement because they appear to have broken the rules that we all have to abide by. They seem to bully people in the marketplace. The judge is the one we collectively hire to set things straight.
I hate bullies, and who doesn't? I'm glad that we can take collective action against them. MS has every opportunity to show the judge that they don't fall into that category.
I, for one, believe that they will get a fair shake.
Sure, good catch, Saturn V was Kero and LOX, Nonetheless this is a big advance, not just because of the Green aspect.
here's why:
Solid boosters are great because they are easier to handle than liquids, but most of all, because whatever weight a liquid booster carries around as turbopumps, plumbing, pre-combustion chambers etc, can now be given to PAYLOAD. That funny little bit of the rocket that actually does something other than look spectacular.
The design and manufacturing simplicity also reduces cost, which also lets us send more PAYLOADS up!
So a nice simple solid has a couple of nasty problems, too. i) uneven burning rates (thrust) is hard to overcome, causing vibration ii) no liquids to cool the nozzle with, so higher nozzle weight iii) can't shut it down, so no abort iiii) no throttle to control thrust, so payload shroud and carry through structure has to be heavier to accommodate higher MAXQ, AKA maximum aerodynamic pressure.
So the next thought is Hybred! Meter the LOX oxidizer flow, and you overcomesall these problems! COOL!! (but not so easy)
Uhh.... how do you get the fuel to stay solid, until it is really needed for burning? and... Uhh... What keeps the solid fuel from melting, and just running out of the "tailpipe"? Idea!!: Make it hard to melt! OOPS! it also doesn't become available for combustion!
So here's what's done:
Put in a little pre-burner at the top of the solid fuel, a "heater" for evaporation of the fuel! Run the vaporized fuel through a restrictor into a second combustion chamber down by the nozzle. Also feed the second combustion chamber with the right amount of LOX, and well, you get the picture.
Not all that simple to model and control in practice. And it's very hard to find dense fuels that melt, vaporize, and burn just right.
So whatever this guy is doing is potentially very useful, and in any case, it's real rocket science, not simple stuff!
Cosmic bodies occur as binaries in about 1 in 10 cases. Binary stars, binary asteroids, binary planets (Earth/Moon, Pluto/Charon).
A primary effect of binaries on each other is tidal stresses, responsible for tides on earth, and heating of Io, which circles Jupiter. The earth has been shown to be squeezed slightly by the moon's gravity. This has been shown through laser rangefinding measurements of orbiting satelites.
IMOH tidal forces on Earth by our binary partner is also responsible for our realatevely strong magnetic field. The magnetic field deflects the solar wind which might otherwise strip away atmosphere, though this hasn't happened with Venus.
So, although the axis tilt stuff isn't right (conservation of angular momentum), I do agree that we should fobably factor in larger moons, of the binary partner size...
The study doesn't take into account the moons of gas giants. It either Jupiter or Saturn were "in the goldilocks zone" (not too hot, not too cold!), then several of their moons (Europa, Calisto, etc) would be very Earth-like.
Most of the studied systems have gas giants in close-in Earth-like orbits...
Maybe most stars in our neighborhood have habitable planets.
IMHO one of the "surprising legal constraints" boils down to this: when voicing negative things about others, I must make it clear that I am either speaking (i) about something I have witnessed as an event, or (ii) that it's my opinion, or conclusion, or unproven theory, or whatever. In short, I have to avoid assiduously slamming another falsely. This meme showed up 3500 years ago "Thou shalt not bear false witness against thy neighbor"
Of course, IMHO, the other "surprising legal constraint" is that proprietary material should not be divulged. "Thou shalt not steal".
The ins and outs of today's laws vary from one jurisdiction to another, but not the age-old principles of right and wrong...
If the Admiral gets the US into the "big brother" mode, other countries will nonetheless adopt this new, more enlightened mode. I can't imagine Germany going back to the nazi mode. Their law doesn't even allow phone companies to keep records of what number called what other number. Back when, the Nazi's used that kind of records to clamp down on dissent. And how about the Dutch, Danes, Sweeds, etc? Or the Lithuanians: their experience with Stalin would probably give them pause for thought....
Sometimes the US (as all other orgs) overdoes this or that. But the point of democracy was never to get the best possible laws at all times. It's really just that we get a collective, periodic chance to correct excesses by dumping the bozos who get it wrong.
Just look at Trent Lott... "you can't fool all the people all the time" - P.T.Barnum
Sure, other folks got in the air, and failed to control their flight, or sustain it.
The key is: as others say, methodical dogged pursuit of their goal.
1> They invented the wind tunnel, which proved that the figures published by Lilienthal were wrong, specificly as regards to optimum wing cross section ("wing section").
2> They invented the airplane propeller. Notice in all photos and drawings of the other people's earlier attempts that their propellers are of designs that have less than 25% of the efficiency of the Wright's design. That would force the others to have engines with a better than 4:1 improvement in power:weight ratio in order to get enough propulsive power to overcome drag for sustained flight. BY the way, Orville Wright wrote about this aspect in his book "How We Invented the Airplane" (still in print: ISBN 0-486-25662-6). Just as with wing sections, ALL the published data and theory on "air screws" was wrong at the time.
3> They selected their flight test location with great care. They selected Kitty Hawk over Coronado (San Diego, CA) in spite of Coronado's better winds. The reason? Lillienthal got killed when his glider broke up in mid-flight, and he fell to his death. So they opted for the dunes at Kitty Hawk, where they could do gliding flight tests, for long times and distances, while only inches above the ground. They DID crash a lot. Then they fixed their craft, and tried again. As they had planned.
4> The flight tests proved the need for a rudder to control YAW, not the direction of flight (HEADING and TRACK), as in the failed designs of others.
5> The flight tests also proved the need for a horizontal stabilizer (PITCH control), an all flying canard, as in many of Dick Rutan's modern designs.
6) The skids were the lowest drag solution for a landing gear. They were augmented by a fall-away dolly and rail arrangement for powered takeoffs. Skids are still used in experimental space-return vehicles, for the same reasons. Again: an engineered invention of their own design to overcome fundamental problems.
7) The motor, which they designed and built themselves, had a 50% excess power margin. The power margin is needed to accelerate an airplane for takeoff, and of course, it allows for growth.
8> The prone pilot position was selected for low drag, which NOBODY else was hip to. Lilienthal hung from his gliders, and others sat on their machines. In later designs they sat upright, when their powerplant was beefed up.
All subsequent flyers used everything outlined above, and dropped the erroneous ideas that came before. Curtis (USA) came out with hinged control surfaces at the trailing edges and tips of wings and other airfoils. He tried to get a patent, but it was eventually ruled to be such an obvious refinement in the Wrights design, that it was not worthy of patent protection.
One final point: there is a brand new set of tests just starting, with a modified F18-A. They are using computer-controlled wing warping (to control ROLL, just as the Wrights did to determine HEADING and TRACK) in order to (a) reduce weight, and (b) improve roll rate.
The more things change, the more they stay the same!
Since the flight was terminated prior to staging, the all-new cryogenic second stage is still not flight tested. That makes getting a new payload for the next flight will be that much more difficult. Insurance rates will be very high, as in every first flight, even if the cause of this launch problem is clearly found and solved.
speculative analysis of failure:
fact 1: Cooling pressure in the first (cryogenic) stage was nominal until T+00:01:36 (96 sec) as per BBC report
fact 2: Overall thrust by stage 1 and control of trajectory is dominated by the strap-on solid boosters until solids separate. This happens at about T+00:02:00
fact 3: further stage 1 (cryogenic) core engine problems developed at T+00:03:16. The bird was no longer in a nominal trajectory. per Arianespace This is well after solids separation. The nature of the engine problems were not specified right away. "flight control difficulties" were cited later by Arianespace. (No Kidding!)
My conclusion:
The cryogenic coolant circuit in the Vulcan-2 nozzle seems to have developed a leak, dropping the cooling system pressure.
The uncooled nozzle section in the immediate vicinity of the leak was immediately subjected to excess thermal shock. The coolant is rocket fuel (LH2 or LO2). If injected into the nozzle (as opposed to dumping outside the nozzle) then nozzle pressures and temperatures spike locally. In addition, the exhaust turbulence increases, along with acoustic loads. These factors could easily lead to burn-through of the nozzle wall near the coolant leak location. Burn-through leads to increasingly asymmetric thrust, which the control software does not figure in with its control laws. Unpredictable results (ie trajectory) follow.
Note that the US Space Shuttle Main Engines (SSME) have a similar cooling design, which had frequent cracking problems. The problems were sometimes discovered after flight, since the engines were thoroughly inspected post-flight. Static ground tests did not seem to uncover all failure modes. The Vulcan-2 is well tested, but no engines can be inspected post-flight since the booster burns up in re-entry.
The problems of extreme thermal shock, extreme thermal gradients, and enormous loads and vibrations make for a brutally unforgiving environment. Good Luck, folks!
Slashdot Mirror
orbit inclination
What you saw was the Exoatmospheric Kill Vehicle, developed for SDI ("Star Wars") as part of a concept called "Brilliant Pebbles".
ground-based telescopes (which had been used to inspect some earlier shuttles). Those pictures had very poor resolution, so they were useless. This little bird takes pictures from a fe feet away. BIG difference!
Not to Columbia, but I bet the investigators would love to have detailed pictures...
Sorry, I wasn't clear on that point. Sure, more launches cost more bucks. But there's something else involved.
Almost every ISS structure payload had to be redesigned since the high inclination orbits have lower max payload weights fo the shuttle. The missions (construction tasks) then also needed to be redesigned. In addition, since more trips were needed, the constuction sequence had to be strtched out. Once the station was manned, that also increased the consumeable supplies fraction that had to be brought up on every mission. Which further reduced payloads...
Beyond that, the existing Russian gear had to be integrated and qualified, and new Russian gear and proceures had to be worked out. And all this happened in the atmosphere of mistrust that followed the Cold War. Then there was the language thing, and the intercontinental / time zone problems.
The estimated budget kept going up. No surprise to me. Did anyone that forsee all those costs back in '88?
True at the time, but the problem has been addressed since then. That was 1988, this is now.
APU's have been found to be a weakness
idem dito
An "economical" launch system is what the military needs to launch its crushing backlog of spy satellites and Vandenburg is the only launch site which can make polar orbit without going over populated areas.
The EELV program delt with this problem. Look it up on Google. Beau Coups references. Also, DoD is moving to more small payloads, not ever larger ones...
The SSME bell is not being adequately inspected for hairline cracks which could fail catastrophically during launch.
Old news, delt with long ago...
NASA continues to invest more and more money in SRB research to the exclusion of other areas of far greater weakness in the Shuttle system. Obviously, it will not invest adequate money in those areas...
NASA does a wide variety of research, though obviously not every project gets the funding that you or I would like to see. Write your congressman if you know about "fluff" projects, or if you have one that you feel deserves funding. DARPA also funds projects, and is not shy about "High Risk/High Reward" bets.
That's being a bit loose with the facts...
NASA continues to have a major say in ISS and Shuttle development. The contract is like that between a remodeler or a builder and the homeowner. You get the picture...
The station orbit choice, all by itself, was responsible for a huge cost increase. A high inclination orbit was chosen to bring the Ruskies on board. If the everyday folks in Russia couldn't look up and see the thing, they wouldn't think of it as their own, and they wouldn't give up MIR. Politics, plain and simple. Not good or bad, just politics.
BUT: High inclination orbits take more fuel to get to ==>> leads to ==>> less payload ==>> leads to ==>> more flights & redesign of heavy payloads ==>> leads to ==>> higher costs ($$$$).
I estimate (personal guess) that the high inclination orbit cost us something like 20% more $ per pound in orbit for ever pound for the lifetime of the ISS!!!!
Anyway, you get the picture, neither Boeing, nor NASA, are really "cheats or idiots". There is a cost associated with the "International" part of the ISS, and I'm glad we're paying it.
The problem is that there's too much lift, and you want the thing to come down. So the S turns convert the lift vector into somewhat sideways vectors, which, because the rolls are reversed, cancel each other out over time. The track goes left and right, but you still are generally headed into KSC.
However, the flight is very smooth and gentle through the first couple of S turns, so that the tile surfaces aren't subjected to thermal shock, I believe.
Nothing has to "fall off". If the TPS tiles are damaged, then the hypersonic flow can experience a very large disturbance; standing shock waves result. Wherever they impinge on structure, temperatures rise immediately to much higher levels. For example, a shock from the leading edge of the wing could impinge on the side of the shuttle, the OMS pods, or the tail. This happened on one of the X-15 flights. The shock burned through most of the titanium tail in seconds. And this was at mach 5, not even a third of the orbiter speed!
Ice hasn't disloged or damaged any tiles for some time now. The ice used to build up on the top of the external tank (ET), and was shed during the liftoff. Nowadays, there is a big cap over the external tank, and dry nitrogen gas is blown down over the ET nose, so no ice forms. On this launch, some of the foam insulation was shed. It isn't hard like ice; it's kind of light and foamy like a dry sponge. It could have done some damage, but not like the ice used to do. The ice used to damage the external tile surfaces of ceramic (white) tiles (not the back carbon/carbon tiles).
In addition, whole tiles used to come off because they weren't glued in place properly. This hasn't happened in the last 75 flights, because of an improved pull test, which yanks off the improperly glued tiles.
The final tile failure mode which has been fixed was this: water intruded into the joints between the tiles while the bird was on the pad (in rainstorms etc). The water flashed to steam during reentry (if memory serves) and that popped the tiles off. Improved seals between the tiles fixed that problem around the same time as the improved "pull test".
In spite of all these improvements, some problem needs to be found and fixed. Given the very low aerodynamic loads when it came over the coast (at 7:43) a chief suspect would be still have to be a failure of the Thermal Protection System (TPS), just as you say.
In general, the real experts refuse to speculate as to causes. You are best served by ignoring anyone who discusses causes without first laying out hard engineering evidence.
The general process we will now see is this:
1. Impound and secure all available data and have all involved parties (such as flight controllers) make notes on the events while they are still fresh in their minds.
2. Collect all debris, and note where each piece was found.
3. Start analysis, based on the known facts.
This is a case where the structure clearly broke up in flight. Because of this, the breakup sequence will be of great interest. It is usually determined by examining the pattern of the debris on the ground. In recent years, sophisticated analysis of radar returns have provided extraordinary insights into breakup sequences.
Telemetry from the shuttle (sent via the TDRS satellites) may also prove to be very valuable in this case. Shuttles are very well instrumented with sensors that show heating, structural stresses, control system inputs, and, of course, attitude, motions, and accelerations.
There is a blackout period for returning spacecraft, where they are enveloped by a plume of high temperature gas. The temperatures are high enough to strip electrons off, so the gas is a plasma which blocks radio transmissions. At this point, NASA is indicating that they were receiving telemetry, and that the loss of communication was the first (and prime) indicator of a mishap.
If memory serves, there are black box recorders on board shuttles: both a Cockpit Voice Recorder (CVR) and a Flight Data Recorder (CDR). It seems to me that Challenger CVR tape has never been made public, but makes for rather sobering listening. Don't expect the CVR to be made public. Many countries (such as Canada) forbid the public release of this type of recording.
My heart goes out to those of you who are suffering. Please feel free to contact me with complete privacy.
Social engineering sounds so impressive! Were u a con man?
cheers, man! put it behind u, move on, have fun, and take care!
And aren't there exceptions made in contract law when the parties have "unequal strength", or some such thing?
I've often wondered whether all those strict and draconian terms are enforceable. I didn't realize that claiming enforceability might be regarded as consumer fraud. I like it!
I'd like to see a series of prizes for achievements.
Let Congress, or ESA, or private people pay into the prize pools. And of course, invest the money so that it's increasing all the time.
Possible prize-worthy achievements: (i)getting any single stage vehicle into orbit w/no throw-aways. (ii) getting a whole launch system back to earth and refurbishing it for reuse. (iii) finding water on the moon, and breaking it into H2 and O2. (Or doing the same on Mars.) Or...
MS is facing a judge and his judgement because they appear to have broken the rules that we all have to abide by. They seem to bully people in the marketplace. The judge is the one we collectively hire to set things straight.
I hate bullies, and who doesn't? I'm glad that we can take collective action against them. MS has every opportunity to show the judge that they don't fall into that category.
I, for one, believe that they will get a fair shake.
here's why:
Solid boosters are great because they are easier to handle than liquids, but most of all, because whatever weight a liquid booster carries around as turbopumps, plumbing, pre-combustion chambers etc, can now be given to PAYLOAD. That funny little bit of the rocket that actually does something other than look spectacular.
The design and manufacturing simplicity also reduces cost, which also lets us send more PAYLOADS up!
So a nice simple solid has a couple of nasty problems, too. i) uneven burning rates (thrust) is hard to overcome, causing vibration ii) no liquids to cool the nozzle with, so higher nozzle weight iii) can't shut it down, so no abort iiii) no throttle to control thrust, so payload shroud and carry through structure has to be heavier to accommodate higher MAXQ, AKA maximum aerodynamic pressure.
So the next thought is Hybred! Meter the LOX oxidizer flow, and you overcomesall these problems! COOL!! (but not so easy)
Uhh.... how do you get the fuel to stay solid, until it is really needed for burning? and ... Uhh... What keeps the solid fuel from melting, and just running out of the "tailpipe"? Idea!!: Make it hard to melt! OOPS! it also doesn't become available for combustion!
So here's what's done:
Put in a little pre-burner at the top of the solid fuel, a "heater" for evaporation of the fuel! Run the vaporized fuel through a restrictor into a second combustion chamber down by the nozzle. Also feed the second combustion chamber with the right amount of LOX, and well, you get the picture.
Not all that simple to model and control in practice. And it's very hard to find dense fuels that melt, vaporize, and burn just right.
So whatever this guy is doing is potentially very useful, and in any case, it's real rocket science, not simple stuff!
A primary effect of binaries on each other is tidal stresses, responsible for tides on earth, and heating of Io, which circles Jupiter. The earth has been shown to be squeezed slightly by the moon's gravity. This has been shown through laser rangefinding measurements of orbiting satelites.
IMOH tidal forces on Earth by our binary partner is also responsible for our realatevely strong magnetic field. The magnetic field deflects the solar wind which might otherwise strip away atmosphere, though this hasn't happened with Venus.
So, although the axis tilt stuff isn't right (conservation of angular momentum), I do agree that we should fobably factor in larger moons, of the binary partner size...
The study doesn't take into account the moons of gas giants. It either Jupiter or Saturn were "in the goldilocks zone" (not too hot, not too cold!), then several of their moons (Europa, Calisto, etc) would be very Earth-like. Most of the studied systems have gas giants in close-in Earth-like orbits... Maybe most stars in our neighborhood have habitable planets.
Of course, IMHO, the other "surprising legal constraint" is that proprietary material should not be divulged. "Thou shalt not steal".
The ins and outs of today's laws vary from one jurisdiction to another, but not the age-old principles of right and wrong...
Sometimes the US (as all other orgs) overdoes this or that. But the point of democracy was never to get the best possible laws at all times. It's really just that we get a collective, periodic chance to correct excesses by dumping the bozos who get it wrong.
Just look at Trent Lott... "you can't fool all the people all the time" - P.T.Barnum
1> They invented the wind tunnel, which proved that the figures published by Lilienthal were wrong, specificly as regards to optimum wing cross section ("wing section").
2> They invented the airplane propeller. Notice in all photos and drawings of the other people's earlier attempts that their propellers are of designs that have less than 25% of the efficiency of the Wright's design. That would force the others to have engines with a better than 4:1 improvement in power:weight ratio in order to get enough propulsive power to overcome drag for sustained flight. BY the way, Orville Wright wrote about this aspect in his book "How We Invented the Airplane" (still in print: ISBN 0-486-25662-6). Just as with wing sections, ALL the published data and theory on "air screws" was wrong at the time.
3> They selected their flight test location with great care. They selected Kitty Hawk over Coronado (San Diego, CA) in spite of Coronado's better winds. The reason? Lillienthal got killed when his glider broke up in mid-flight, and he fell to his death. So they opted for the dunes at Kitty Hawk, where they could do gliding flight tests, for long times and distances, while only inches above the ground. They DID crash a lot. Then they fixed their craft, and tried again. As they had planned.
4> The flight tests proved the need for a rudder to control YAW, not the direction of flight (HEADING and TRACK), as in the failed designs of others.
5> The flight tests also proved the need for a horizontal stabilizer (PITCH control), an all flying canard, as in many of Dick Rutan's modern designs.
6) The skids were the lowest drag solution for a landing gear. They were augmented by a fall-away dolly and rail arrangement for powered takeoffs. Skids are still used in experimental space-return vehicles, for the same reasons. Again: an engineered invention of their own design to overcome fundamental problems.
7) The motor, which they designed and built themselves, had a 50% excess power margin. The power margin is needed to accelerate an airplane for takeoff, and of course, it allows for growth.
8> The prone pilot position was selected for low drag, which NOBODY else was hip to. Lilienthal hung from his gliders, and others sat on their machines. In later designs they sat upright, when their powerplant was beefed up.
All subsequent flyers used everything outlined above, and dropped the erroneous ideas that came before. Curtis (USA) came out with hinged control surfaces at the trailing edges and tips of wings and other airfoils. He tried to get a patent, but it was eventually ruled to be such an obvious refinement in the Wrights design, that it was not worthy of patent protection.
One final point: there is a brand new set of tests just starting, with a modified F18-A. They are using computer-controlled wing warping (to control ROLL, just as the Wrights did to determine HEADING and TRACK) in order to (a) reduce weight, and (b) improve roll rate.
The more things change, the more they stay the same!
speculative analysis of failure:
fact 1: Cooling pressure in the first (cryogenic) stage was nominal until T+00:01:36 (96 sec) as per BBC report
fact 2: Overall thrust by stage 1 and control of trajectory is dominated by the strap-on solid boosters until solids separate. This happens at about T+00:02:00
fact 3: further stage 1 (cryogenic) core engine problems developed at T+00:03:16. The bird was no longer in a nominal trajectory. per Arianespace This is well after solids separation. The nature of the engine problems were not specified right away. "flight control difficulties" were cited later by Arianespace. (No Kidding!)
My conclusion:
The cryogenic coolant circuit in the Vulcan-2 nozzle seems to have developed a leak, dropping the cooling system pressure.
The uncooled nozzle section in the immediate vicinity of the leak was immediately subjected to excess thermal shock. The coolant is rocket fuel (LH2 or LO2). If injected into the nozzle (as opposed to dumping outside the nozzle) then nozzle pressures and temperatures spike locally. In addition, the exhaust turbulence increases, along with acoustic loads. These factors could easily lead to burn-through of the nozzle wall near the coolant leak location. Burn-through leads to increasingly asymmetric thrust, which the control software does not figure in with its control laws. Unpredictable results (ie trajectory) follow.
Note that the US Space Shuttle Main Engines (SSME) have a similar cooling design, which had frequent cracking problems. The problems were sometimes discovered after flight, since the engines were thoroughly inspected post-flight. Static ground tests did not seem to uncover all failure modes. The Vulcan-2 is well tested, but no engines can be inspected post-flight since the booster burns up in re-entry.
The problems of extreme thermal shock, extreme thermal gradients, and enormous loads and vibrations make for a brutally unforgiving environment. Good Luck, folks!