# Fixing Hubble

Staff Emeritus
Gold Member
http://science.discovery.com/tvlistings/episode.jsp?episode=0&cpi=111531&gid=0&channel=SCI" [Broken]

The above is a link to a Discovery Science channel show. It is a must watch for all man is space enthusiast. It is on Sunday 11 Mar at 6pm. (that is tonight for this post.)

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Central or Eastern?

isnt it a bit too late to watch it by now?

Drat I missed it. Hopefully they will play it again in summer re-runs.

Staff Emeritus
Gold Member
That was 6pm EDT, so it started 30min after my first post.

Very interesting show. It went over the 1999 missions which pretty much raised Hubble from dead. It covered the expenses, difficulties and delays associated with using astronauts to perform the repairs. They can build a new satellite and but it in orbit for about the cost of a single manned Hubble repair mission.

The trouble is, after each repair mission the capabilities of the Hubble have INCREASED by orders of magnitude. So the scientists are not done with Hubble there is still lots of work for it to do. We just cannot afford manned missions to upgrade and repair.

A University (don't recall which) is working with NASA to build a robot to perform the repairs. This has several advantages over manned missions. The repairs have to be done on very strict time schedule due the participation of men, they can only spend so long on the Hubble then have to come in for a rest. The robot being monitored from the ground can spend days doing a task the space repair men must do in hours. The beauty is, that the tasks required are more suited to robotics then the human hand.

Future generations of satellites will be designed with robotic repair in mind. It seems, for you youngsters who what to work in space, your best bet will be to get a good education in robotics, sensors and control systems as that will be the real work in space for a long time to come.

D H
Staff Emeritus
They can build a new satellite and but it in orbit for about the cost of a single manned Hubble repair mission.

They can? A Shuttle mission costs around $500 million. The Hubble cost over$2.5 billion to construct. Total Hubble costs (operations included) are now around $6 billion. The The James Webb Space Telescope, currently one billion dollars over budget, is now expected to cost over$4.5 billion to build.

A University (don't recall which) is working with NASA to build a robot to perform the repairs.

Wrong again. Rendezvous with an uncooperative target is a very hard task. Repairing a device in space with robots is even harder. One of the main reasons NASA put a Hubble repair mission back on the Shuttle manifest (STS-125) is because NASA found a robotic repair mission to be unlikely to succeed.

Future generations of satellites will be designed with robotic repair in mind. It seems, for you youngsters who what to work in space, your best bet will be to get a good education in robotics, sensors and control systems as that will be the real work in space for a long time to come.

The Space Exploration Initiative involves robotic and human space flight missions, with a primary focus on human space flight. This is where the real money will go for a long time, and it is where the money belongs.

Staff Emeritus
Gold Member
They can? A Shuttle mission costs around $500 million. The Hubble cost over$2.5 billion to construct. Total Hubble costs (operations included) are now around $6 billion. The The James Webb Space Telescope, currently one billion dollars over budget, is now expected to cost over$4.5 billion to build.
This was not to put another Hubble in orbit, but other observation platforms that are capable of doing similar observations.
Wrong again. Rendezvous with an uncooperative target is a very hard task. Repairing a device in space with robots is even harder. One of the main reasons NASA put a Hubble repair mission back on the Shuttle manifest (STS-125) is because NASA found a robotic repair mission to be unlikely to succeed.
The robotics are being tested in the "swimming pool" seems that some do not agree with you. And why is it an uncooperative target? With robotic repair capabilities we would not have to delay missions (as was done in the '99 repairs) to suit the vagaries of human space flight It was these delays that nearly cost us the Hubble as it degraded to a dead hulk in space waiting for the shuttle to come to the rescue. Can we stop maintaining satellites while we wait for a reliable replacement to the space shuttle? Alternatively, how many more shuttle accidents will it take before that death trap is grounded for good?

It is really not clear to me what a man can do in space that a robot can't and I can see lots of things that a robot can and could do that a man can't. There is simply no excuse for putting lives at risk.. There was a space suit failure in the shuttle that had it occurred in space could have cost the life of a astronaut.

Of course I am assuming that a man is setting in the control room on earth watching and when necessary taking control.

The Space Exploration Initiative involves robotic and human space flight missions, with a primary focus on human space flight. This is where the real money will go for a long time, and it is where the money belongs.
Yeah, it is really to bad that NASA, with its budget limitations must be wasting money on man in space when there is so much good science that can be done without it. NASA should concentrate on space exploration and let the commercial sector carry the burden of man in space.

It is my job to repair and maintain expensive complex tools. All of the tools I work on have a wafer handling robot at the core, so I feel that I am perhaps more in touch then the average man on the street with the abilities and limitations of robots.

Ivan Seeking
Staff Emeritus
Gold Member
I got your message while on my way out the door. I'll have to look for the next one. :grumpy:

D H
Staff Emeritus
This was not to put another Hubble in orbit, but other observation platforms that are capable of doing similar observations.

The costs for every single space telescope but the Spitzer are astronomical. Even the Spitzer telescope, at $720 million, exceeds the cost of a Shuttle flight. The only heavy lift vehicle capable of taking most of these monsters into space is the Shuttle. The robotics are being tested in the "swimming pool" seems that some do not agree with you. "If they knew what they were doing they wouldn't call it research." NASA does lots of studies on things that don't pan out for one reason or another. This was one of them. And why is it an uncooperative target? • The Hubble doesn't have a cooperative relative navigation capability. This is the defining characteristic that makes something an uncooperative rendezvous target. • The Hubble wasn't designed for docking. It was designed for be grappled by the robotic arm. A robotic vehicle would have to do this autonomously due to the time lag (vehicle to TDRS to White Sands to ground station, and then back again). Buffering of signals in computers adds quite a bit to this inherent speed of light delay. • The repair vehicle has to be able to handle a dead and tumbling Hubble. This requirement makes the Hubble not only an uncooperative target but a hostile target. Yeah, it is really to bad that NASA, with its budget limitations must be wasting money on man in space when there is so much good science that can be done without it. NASA should concentrate on space exploration and let the commercial sector carry the burden of man in space. I could turn this around and say something equally silly such as "It is really too bad that NASA, with its budget limitations must be wasting money on space science when they should be spending every cent they have human space flight". We need the robotic space program to find out what will be there when we do send people to the Moon, Mars, and beyond and to find out how to make it sufficiently safe to balance the risks of sending people there. Anything else done by the unmanned program is a nice to have. It is inappropriate to compare the cost of unmanned space probes with human spaceflight programs because the unmanned and human programs exist for different reasons. The cost of the science performed by these very expensive unmanned probes should instead be compared to science done on the ground. For example, how good could we make ground-based telescopes if we spent$4-6 billion (the cost of a Hubble or a Webb) on them? The LSST, at a paltry $15 million, will have an image quality that comes close to that of the Hubble. What would a two order of magnitude budget increase do for ground-based systems? Staff Emeritus Science Advisor Gold Member http://history.nasa.gov/hubble/" [Broken] which confirms that the robotic Hubble repair mission has been killed. I would have to say that using this as a reason to justify man is space is circular logic. The robotic mission was canceled for a manned mission after the reemphasis of man in space goals of NASA. I would bet the most of the billion dollar cost would be a one time develepment costs, once that investment was made individual repair mission costs would be MUCH lower then manned missions. This could be the end of Hubble, since getting the shuttle into space is pretty iffy, it may or may not make it there in time. To bad we are putting all our eggs in such an unreliable basket. I am hoping that the work in robotics continues at some level. Last edited by a moderator: SpaceTiger Staff Emeritus Science Advisor Gold Member For example, how good could we make ground-based telescopes if we spent$4-6 billion (the cost of a Hubble or a Webb) on them? The LSST, at a paltry \$15 million, will have an image quality that comes close to that of the Hubble.

I think you're misunderstanding the primary science goals of these projects. No amount of money is going to make UV or far-infrared light visible from the ground. The LSST is an optical survey telescope and doesn't have Hubble's UV or Webb's IR capabilities. It's true that, with the advent of adaptive optics, there are few reasons to do optical astronomy from space, but that only covers a very small part of the electromagnetic spectrum. The pretty pictures you see from Hubble are useful for science, but are mainly for public relations. The real tragedy of the loss of HST, IMO, will be the loss of the UV capabilities. Hopefully it will be replaced with a cheaper UV probe in the near future. As for Webb, it will also have an optical camera, but most of the science coming from it will be in the IR.

Long story short, optical image quality is not the main reason for space science. We depend on space probes for our observations in most of the electromagnetic spectrum (far-UV, far-IR, X-rays, gamma rays, and parts of the microwave spectrum). Ultimately, the question is whether the public puts higher priority on people in space or knowing the answers to deep scientific questions. Personally, I'd love to see both, but I think the latter will give a much greater return per dollar spent and certainly won't be picked up by the private sector.

russ_watters
Mentor
This was not to put another Hubble in orbit, but other observation platforms that are capable of doing similar observations.
I'm not so sure that's true - being an optical telescope gives the Hubble an inherrently large size and because of that, only the shuttle could loft it into orbit. So whether you are going up to service it or going up to place a replacement in orbit, it should cost about the same (minus the cost of the telescope itself, of course), shouldn't it?

Staff Emeritus
Gold Member
I'm not so sure that's true - being an optical telescope gives the Hubble an inherrently large size and because of that, only the shuttle could loft it into orbit. So whether you are going up to service it or going up to place a replacement in orbit, it should cost about the same (minus the cost of the telescope itself, of course), shouldn't it?

I am just trying to report some of the contents of the linked show. They gave an example of an observatory satellite built and put into orbit for about the cost of a single manned shuttle mission. It may have been an X-ray or gamma ray observatory, unfortunately I was not taking notes during the 2am showing that I caught.

D H
Staff Emeritus
http://history.nasa.gov/hubble/" [Broken] which confirms that the robotic Hubble repair mission has been killed. I would have to say that using this as a reason to justify man is space is circular logic. The robotic mission was canceled for a manned mission after the reemphasis of man in space goals of NASA.

The commission that investigated the Columbia disaster recommended againts the then-planned Shuttle HST repair mission. NASA investigated a robotic repair mission as an alternative to the Shuttle mission. However, NASA scrubbed the robotic repair mission because it was too costly and because too many things could go wrong (mission success was far from guaranteed). NASA put the Shuttle HST repair mission put back on the docket only after an very strong outcry from scientists and citizens.

I would bet the most of the billion dollar cost would be a one time develepment costs, once that investment was made individual repair mission costs would be MUCH lower then manned missions. This could be the end of Hubble, since getting the shuttle into space is pretty iffy, it may or may not make it there in time. To bad we are putting all our eggs in such an unreliable basket.

Research and development costs. Research is needed to overcome some basic problems with robotic rendezvous with an uncooperative/disabled/hostile target and with robotic repair in space. Doing so properly would require some demonstration missions prior to operating on some valuable asset such as the Hubble. The Shuttle is an unreliable basket? Try again. An untested rush-job of a robotic repair mission - now that is an unreliable basket. There have been two Shuttle failures in well over 100 flights. Not that that is very good, but it is a better success rate compared to that achieved by the unmanned space program.

I am hoping that the work in robotics continues at some level.

I am, too. We need a combination of human and robotic spaceflight to make space operations truly viable.

I think you're misunderstanding the primary science goals of these projects. No amount of money is going to make UV or far-infrared light visible from the ground.

I agree that a ground-based space observation system cannot see much other than radio and visible light. IR, UV, and X-ray observatories can only be space-based. You are, however, misunderstanding my point: The costs and benefits of those space-based observatories should be weighed against the costs and benefits of ground-based science. Scientists from all fields could come up with a research budget that drains the entire world economy. Choices have to be made. Very expensive choices such as space-based research needs an very compelling payoff. IMHO, a lot of money spend on space-based science would be better spent on ground-based science.

Personally, I'd love to see both, but I think the latter will give a much greater return per dollar spent and certainly won't be picked up by the private sector.

Personally, I'd love to see both also. I think that sending humans into space, and not just LEO, will have a much, much greater dollar return than studying black holes in some remote galaxy.

The private sector will not pick up true human spaceflight any time soon. Virgin Galactic will be making suborbital flights. There is a huge gap between sending people on a short up-and-down joyride and sending people to the moon. It is premature to talk about turning all aspects of human spaceflight over to an industry that does not yet exist.

The field of aeronautics provides a good comparison. Humanity has had viable flying machines for over a century now. NASA (the National Aeronautics and Space Administration) still does some aeronautics research because the private aviation sector still has some gaps despite being a century old.

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SpaceTiger
Staff Emeritus
Gold Member
Very expensive choices such as space-based research needs an very compelling payoff. IMHO, a lot of money spend on space-based science would be better spent on ground-based science.

Such as? An entire community of astronomers is devoted to finding the most cost-effective means of answering the scientific questions that interest them. If you have ground-based means of studying those things addressed by Chandra, Spitzer, etc., I'm sure that they'd love to hear them.

Personally, I'd love to see both also. I think that sending humans into space, and not just LEO, will have a much, much greater dollar return than studying black holes in some remote galaxy.

Are you familiar with the science that comes out of space-based observatories? For example, WMAP recently gave us a stunning view of the origins of the universe itself for just 150 million dollars. In the meantime, what have been the returns of the manned space program in recent years? A space station nobody cares about? A shuttle disaster?

NASA is far ahead of the private sector in manned spaceflight, but what are the ends? In the '60s, the moon landing was of great symbolic importance, particularly in a world caught up in a Cold War. But times have changed. Even if we were to set foot on Mars tomorrow, would it really be worth the money and risk of human life spent to get there? At least with the private development of manned spaceflight, there will be a clear end (i.e. to make money). The stimulus to do so will eventually lead to safer, more cost-effective technology. That's not to say that NASA should stop research into manned spaceflight, but I simply don't see what a huge monetary commitment is going to do for us?

D H
Staff Emeritus
Such as?

Such as something completely different. Research into human longevity, drastically more efficient solar cells, a collider the size of Texas.

Are you familiar with the science that comes out of space-based observatories? For example, WMAP recently gave us a stunning view of the origins of the universe itself for just 150 million dollars.

And what exactly is the monetary return from that 150 million?

Even if we were to set foot on Mars tomorrow, would it really be worth the money and risk of human life spent to get there?

Yes. I would value that a whole lot more than a pretty picture of the universe. Right now, Congress funds NASA at a pittance, around 2/3 of one percent of the federal budget. Choice have to be made. I, for one, finally like the choices that have been made.

At least with the private development of manned spaceflight, there will be a clear end (i.e. to make money). The stimulus to do so will eventually lead to safer, more cost-effective technology.

That is pure conjecture and is not borne out by fact. Look at the auto industry. The auto manufacturers have a clear end (i.e., to make money). The auto you drive today would not be nearly as safe as it is without government research and intervention.

SpaceTiger
Staff Emeritus
Gold Member
Such as something completely different. Research into human longevity, drastically more efficient solar cells, a collider the size of Texas.

So it seems your point has shifted out of convenience. Before we were comparing Hubble and LSST, now you're saying you'd rather see more money to sciences other than astronomy? Obviously, that's just a matter of personal preference, but I'm not sure why you'd rather know more about the next generation model of particle physics than the origins of the universe.

And what exactly is the monetary return from that 150 million?

Since when is NASA's objective to make money? By "return", I'm talking about scientific yield, cultural value, etc. Your taxes aren't like an investment -- you don't get money back if NASA researches something that the private sector finds useful.

Yes. I would value that a whole lot more than a pretty picture of the universe.

I just spent two posts explaining to you how this isn't what the space telescopes do. I'm glad it was time well spent.

Right now, Congress funds NASA at a pittance, around 2/3 of one percent of the federal budget. Choice have to be made. I, for one, finally like the choices that have been made.

Oooohh, this is a political thing. I see now. Yeah sure, yay bush, republicans, whatever.

That is pure conjecture and is not borne out by fact.

It would pretty much have to be, seeing that it hasn't happened yet. Safety standards and developments in safety technology are different things. With automobiles, the private sector has certainly done a great deal of work on the latter.

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D H
Staff Emeritus
So it seems your point has shifted out of convenience. Before we were comparing Hubble and LSST ...

There is no shift of convenience. I said
The cost of the science performed by these very expensive unmanned probes should instead be compared to science done on the ground.
I did not specify which science in this sentence. When I said science done on the ground, I meant just that. Research into human longevity, drastically more efficient solar cells, a collider the size of Texas are all examples of science done on the ground, as is the LSST. I mentioned LSST as one example of how science done on the ground is much cheaper than space science. I mentioned several others. Do you want more? (Hint: I can list a lot of science projects that cost less than 6 billion dollars.)

...now you're saying you'd rather see more money to sciences other than astronomy? Obviously, that's just a matter of personal preference, but I'm not sure why you'd rather know more about the next generation model of particle physics than the origins of the universe.
To answer this specific question, yes. Ignoring the possibility that the next generation of particle physics and the origins of the universe are interrelated, I'd much rather we know more about the next generation of particle physics than the origins of the universe. The payoff to humanity is greater.

Since when is NASA's objective to make money?
Congress has measured the value of scientific research monetarily for a long time.

By "return", I'm talking about scientific yield, cultural value, etc.

Translate "scientific yield" and "cultural value" into dollars. Sorry, but that is what Congress and the people who elect Congresscritters want. The arts community is not pressured to yield a measurable return, and they get funding commensurate with that lack of return.

Your taxes aren't like an investment -- you don't get money back if NASA researches something that the private sector finds useful.

This is so wrong I don't know where to start. Funding something with potentially huge benefits in the long term but is too expensive and risky in the short term is where government spending on research has had the biggest payoff.

I just spent two posts explaining to you how this isn't what the space telescopes do.

I just spent several posts explaining to you why space science should compete with more mundance ground-based technology programs. I am glad that was time well spent.

Oooohh, this is a political thing. I see now. Yeah sure, yay bush, republicans, whatever.

Both parties are to blame for NASA's budget (or lack thereof). NASA has been underfunded by Republican and Democrats alike.

The Columbia disaster was a wake-up call to NASA. If we are to send people into space, it had better be for something worthwhile. Sending people into low Earth orbit does not qualify as worthwhile. Sending people to the Moon, Mars, and beyond does qualify. The initiative was not something foisted on a reluctant space agency. Far from it: NASA started work on the Exploration Initiative well before Bush brought the idea to Congress.

Staff Emeritus
Gold Member
I would value that a whole lot more than a pretty picture of the universe. Right now, Congress funds NASA at a pittance, around 2/3 of one percent of the federal budget. Choice have to be made. I, for one, finally like the choices that have been made.

YOU value a man on Mars, but what is the value to science? Virtually nil. Why should we fund space tourism? That is the job of the commercial sector. Let Donald Trump build a hotel on the moon or mars or on the sun for all I care. That is the importance of man, or should I say tourists in space. We simply cannot afford glorious missions for adventurous astronauts, there needs to be a scientific gain from each and every mission.

There is much exploration that needs to be done that DOES NOT need a man in space. Let us do that then in a generation or 2 when maybe are REAL reason for man in space can be found they will have much better technology and lots of experience putting things into space, so manned missions will be easier and safer.

Meanwhile the cancellation of the robotic repair looks to be a political decision. The shuttle is no safer this year then it was last. There is a measurable high probability, that once docked with the Hubble the shuttle will have to do a emergency return to earth. Which means, while the astronauts MAY return safely to earth, the Hubble will be jettisoned like a toilet dump, fated for a fiery return to earth. So not only does this decision put astronauts at risk it places the Hubble at risk.

I agree that maybe some of the space funds (even better would be war funds) should be redirected to research to guarantee the livability of earth for my great grand children. To me this means alternative energy sources to free us from the noose of fossil fuels. But I think that funds earmarked for man in space should be the ones diverted.

SpaceTiger
Staff Emeritus
Gold Member
There is no shift of convenience. I said

I did not specify which science in this sentence. When I said science done on the ground, I meant just that. Research into human longevity, drastically more efficient solar cells, a collider the size of Texas are all examples of science done on the ground, as is the LSST. I mentioned LSST as one example of how science done on the ground is much cheaper than space science. I mentioned several others. Do you want more? (Hint: I can list a lot of science projects that cost less than 6 billion dollars.)

This is getting kinda silly. It sounds like you're claiming that space research isn't worth it because, per mission/project, the average cost is much higher than projects done on the ground. The field of astronomy has experienced a major boom in the past 10-15 years, primarily because of space-based observatories. Yes, there were successful ground-based missions that were cheaper, but it doesn't take a class in logic to realize that this doesn't mean the space missions weren't worth it.

Just answer me this, are you saying that you'd rather see more money devoted to other areas of science and less to physics and astronomy? If so, we'll just have to agree to disagree. If not, then your opinions run contrary to those of the scientists who know a lot more about the best of use of money in those areas.

To answer this specific question, yes. Ignoring the possibility that the next generation of particle physics and the origins of the universe are interrelated

Possibility?

We know they are. All of the field theories tested at particle accelerators were born after inflation, which is tested by space probes like WMAP. Furthermore, the properties of dark energy are of great interest to particle physicists and gravitational theorists, and this is one of the things tested by those distant observations of galaxies and black holes you were talking about.

I'd much rather we know more about the next generation of particle physics than the origins of the universe. The payoff to humanity is greater.

How so?

Congress has measured the value of scientific research monetarily for a long time.
Translate "scientific yield" and "cultural value" into dollars. Sorry, but that is what Congress and the people who elect Congresscritters want. The arts community is not pressured to yield a measurable return, and they get funding commensurate with that lack of return.

Yet this whole debate is about the fact that we each value these things differently. Could I put a dollar amount on the value of the WMAP space mission? Perhaps, with a lot of effort, and even then I wouldn't see the point. It wouldn't be the same as your dollar amount.

This is so wrong I don't know where to start.

Well, let me know when you get your check in the mail.

Funding something with potentially huge benefits in the long term but is too expensive and risky in the short term is where government spending on research has had the biggest payoff.

That generalization is a bit too broad for you to realistically prove in a debate like this. I suggest we focus on the question at hand.

I just spent several posts explaining to you why space science should compete with more mundance ground-based technology programs. I am glad that was time well spent.

If this is all your posts were meant to convey, then it certainly wasn't time well spent. That's a triviality. This competition always exists in astronomy. Every time someone proposes to make a space telescope or applies for an observation on a space telescope, the committee asks the proposer whether or not it's something that could be done from the ground. Ultimately, it seems as if the issue is that you simply don't value astronomy enough to give it many of your tax dollars.

Both parties are to blame for NASA's budget (or lack thereof). NASA has been underfunded by Republican and Democrats alike.

I think we both support a bigger budget for NASA, the question was the allocation of the existing funds. I would like to see people on Mars before I die, but I would also like to see some of our basic questions about the origin of universe answered. To me, the latter is more important. To you, it seems that the former is. That's fine, it's just a matter of personal preference.

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D H
Staff Emeritus
I am hoping that the work in robotics continues at some level.

NASA is continuing work on autonomous rendezvous. This is an essential aspect of the Exploration Initiative. Some projects:

• DART, a failed attempt. http://www.nasa.gov/mission_pages/dart/main/index.html" [Broken]. DART collided with the target. Rendezvous is essentially a controlled collision, but this collision was not controlled. Marshall engineers made a complete mess of the relative navigation.
• Orbital Express, ongoing (joint DARPA/NASA project). http://www.darpa.mil/tto/programs/oe.htm" [Broken] Orbital Express launched on March 8. NASA Watch reports some unspecified problems.
• Autonomous Transfer Vehicle (ATV), a joint ESA/NASA project. http://www.esa.int/SPECIALS/ATV/index.html". ATV's rendezvous technology derives from Russia's Progress vehicles. ATV was supposed to have had its first docking mission with the ISS a long time ago. Current schedule is next year.
• H-II Transfer Vehicle (HTV), a joint JAXA/NASA project. http://www.jaxa.jp/projects/rockets/htv/index_e.html" [Broken]. The HTV doesn't dock with the Space Station. Instead, it comes to a stop close to the Station and is then grappled by the Station's robotic arm. Like ATV, HTV was to have had its first rendezvous mission a long time ago (2001). Current schedule is 2009.
• Commercial Orbital Transportation Services (COTS). Both COTS vehicles (SpaceX Dragon, http://www.spacex.com/dragon.php" [Broken]) will berth rather than dock with the ISS.

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D H, I symphatize with your demonstration of the limits of robots, doing a persons (m/f) job. I had exactly the same problem as a fighter pilot in the airstaff explaining the limits of unintelligent systems (unmanned aerial vehicles) in the cognitive decision loop inherent to precision multi task performing operations. This was both against the mainstream of UAV constructing engineers, unexperienced in the operational environement and for whom the sky was no limit whatsoever and the coin counters seeing the difference in costs between model air planes and jet fighters.

The question remains when you are best off either with brained operators with limited tools or brainless operators with a wealthy assortiment of tools. You'd be surprised to see how often you have to settle for the first one due to the probihitive problems in the decision loop with the latter.

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D H
Staff Emeritus