In addition to hardened materials, one of the difficulties with transsonic speeds is that air will not behave itself properly and lift efficiency drops off quickly. This is a limiting factor in piston propeller and turboprops as well. The tip of the propellr can not exceed the sound barrier or it will not be able to pull as efficiently.
It may be possible to design a tip capable of ggenerating lift/pull in a supersonic environment, but I don't know of anyone trying to do so.
Concorde and other supersonic aircraft also have to, for similar reasons, slow the speed of engine inlet air below supersonic speeds before combustion.
I believe the Scramjet principle does not require the airstream to be slowed below supersonic speeds.
(At the time, I knew a 135 pilot who said the really loud ones were the result of injecting water spray into the combustion process to boost thrust on launch.)
That may be true. I'm not sure if I have heard one with water injection or not.
Interestingly, I know that the huge amount of water they spray into the launch pit for the Space Shuttle is to dampen sound, whereas I thought it had something to do with keeping things cool. Interesting that changing when you dump in the water has the opposite effect on the noise level.
I live next to Tinker AFB, and our KC-135s are loud, but nowhere near as loud as the B-52s that occasionally take off.
I never got to hear a Concorde, though.
Right. Just like we prohibit our airlines from buying Airbus, Embraer, Bombardier, Saab, etc, and won't let those planes land here.
I mean really, if we wanted to help our struggling airplane manufacturers, wouldn't it make more sense to stop the manufacturers that sell hundreds of airframes, rather than the one that will sell maybe 50 if they're lucky?
Cheer up. We have a 100+ year supply of coal, even factoring in the current growth of energy use. Unfortunately, coal is useless in airplanes, but probably what we need to do more or less immediately is to start running boats, electric plants and other things that CAN burn it on coal. And use Oil for airplanes and other things. Also, there is always nuclear energy, which I'm sure the treehuggers will take more kindly too when the oil burning electric plant shuts down, and they can no longer run their espresso machines.
The problem really comes down to the fact that companies are unwilling to pay for R&D. Bell Labs used to pour billions into R&D and this made them one of the largest contributors to innovation in the 20th century. Companies that pour huge amounts of money into R&D reap huge long term profits. However, short term profits and short term cash reserves are sacrificed in order to do this. Publicly held companies are at the mercy of us, the public, who demand consistent short term profit and as such, can not really be blamed for cutting R&D budgets. Certainly a bird in the hand is worth two in the bush. But is a bird in the hand better than a hundred in the bush? A thousand? A million? At some point, your expected return from firing randomly into that bush is higher than one bird.
Unless we as Americans wake up to the necessity of R&D and thinking in the long term, we are going to end up with no innovation and eventually no jobs. Greed is going to make us go broke.
The spin of the Earth is definitely a factor, however, the Earth is not just going to spin under you. You still have the atmosphere to deal with. In some locations, it runs counter to the rotation of the Earth, and in other locations, it runs with (and faster than) the rotation of the Earth. At very few place and for very short lengths of time, does any part of the atmosphere move with the rest of the planet.
The internet/voip and other communication mediums have obsoleted the necessity for face to face contact and the costs associated with business travel.
Uh, huh. Why is it that most of the jobs on Dice.com rquire 25% to 100% travel? And why do very few companies allow you to telecommute?
One more problem with supersonic jetliners is terrorism. If the emir's warriors got hold of an M2+ plane, it would be virtually impossible to stop, unlike subsonic planes, as fighter jets couldn't catch it in time. And when it hits...
Fighter jets would not be able to catch a conventional jet plane in time either. They didn't even catch up to a Cessna 172 until it was nearly to the center of the ADIZ around D.C. A single Concorde impacting at top speed (1.1M at low altitude or twice of those B767s) would have probably gone right through BOTH the north and south towers of WTC!
Which, as it turns out, would have been better for everybody, because at least the towers would still be standing.
The FAA prohibits supersoinc flight over US Soil @ any altitude without prior special approval.
That's interesting since the FAA has no jurisdiction over altitudes above 60,000 feet.
Also, this applies only to civilian craft, as the military happily creates sonic booms all the time, as does the space shuttle.
The moon is already creeping away from us slowly and thus reducing the tidal influence.
The moon's mass is within an order of magnitude of the Earth's mass. Taking resources off of the moon is similar to taking resources off of the earth. It would take a darn long time for it to become significant.
History makes it pretty clear that when you get Americans, resource interests, and weapons together in one place, but there is already someone else at that place, you can be sure that an application of Rule #2 is coming soon.
You shouldn't use History to try to prove something about Americans. We've only been here a few hundred years. Our nhumber of landgrabbing attempts pale in comparison to those done in European, African, and Asian history.
Re:I'm all for science/technology/astronomy but...
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Back to Moon in 2015?
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Well, there's certainly no clouds, but just like earth, there is night and day on the moon. A lunar day is about 2 weeks in our time. There is no sunny side.
Re:I'm all for science/technology/astronomy but...
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Back to Moon in 2015?
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Not really. They poured all kinds of fuel inside of it, and strapped it next to a huge tank of liquid oxygen, and then stuck two solid rocket fuel boosters on the outside of the tank, but they still only got it to blow up once out of 117 missions.
(The re-entry mishap was not an explosion)
Re:I'm all for science/technology/astronomy but...
on
Back to Moon in 2015?
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· Score: 1
Where are you going to get this inexhaustable supply of propellant gas?
Actually, since the airplane industry likes to use "passenger*miles" to show how much safer they are than driving, NASA could use the same calculation for the shuttle and probably end up proving the shuttle to be MORE safe than an airplane.
The last sentence was intended to inspire students to dream about ever greater achievement and exploration. It read, "Who knows, someday man may even reach the moon."
Sadly, that book is no longer outdated. Who knows, someday maybe that book will be outdated again.
I am man enough to admit that when I saw the Saturn V in the museum at NASA, and thought of what we had once done, and can no longer do, I got tears in my eyes.
I say just design a re-usable launch vehicle that can transport one standard shipping container (the ones they use to ship freight on boats) and all you have to do is design a container for each kind of launch...
Those containers are designed to stack X high and are thus very strong and very heavy. I like your idea, but would say that we should make it where it doesn't need to have stackable strength at all. More like the ones that are used in wide body airplanes (and even those can be stacked a couple high).
When I toured the NASA facility in January, they had a long thick wire running from the gantry down to the ground quite a distance away. The tour operator said that was in case they needed to evacuate the platform in an emergency. I think they got into some sort of vehicle which would run down the wire at something like 50 MPH.
how a timeless entity can act to create something given that he has no time to move in
This shows why opponents and proponents of creationism can never convince each other. Opponents keep wanting to try to understand a creator in terms of universal components of time and material. You ask how a creator could create the universe when he has no time to move in. A few posts up, someone asks how there could be the universe AND be something else (that being the creator). In terms of science, there can't. Nothing can happen without time, and everything is made of matter. Nothing can exist outside of the universe, which is the sum of all matter.
Scientifically, this is true. But I have no problem believing that a creator created the universe, time, nature, scientific principles and so forth, but having created those things doesn't mean that he is limited by those things. He doesn't have to operate in time, doesn't have to be composed of matter, etc. Science can prove that such a creator can not exist in this universe, however, the scientific rules and properties that govern the creation do not necessarily apply to the creator.
That hypothesis makes the assumption that the Intelligent Designer is part of the creation and therefore had to be created Himself. That is not what creationists believe.
Further, going one step lower, your argument could be used as a question to show that Legos don't have to be intelligently designed. They could just exist by themselves.
Except of course, that Legos and the designers of Legos are part of the universe, whereas creationists contend that the creator created the Universe and is NOT part of it.
He died of having AIDS. Cancer killed him.
It is true that AIDS itself does not kill you, but prevents your body from fighting off the actual common causes of death such as pneumonia. However, if someone doesn't actually HAVE AIDS, then you can't say that they died of having AIDS, but something else killed him. For example, Graham Chapman denied having AIDS, and there is no reason for him to lie, since he was openly homosexual. We must assume he was telling the truth and did not have AIDS. Therefore, he died of cancer, and cancer is what killed him.
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In addition to hardened materials, one of the difficulties with transsonic speeds is that air will not behave itself properly and lift efficiency drops off quickly. This is a limiting factor in piston propeller and turboprops as well. The tip of the propellr can not exceed the sound barrier or it will not be able to pull as efficiently.
It may be possible to design a tip capable of ggenerating lift/pull in a supersonic environment, but I don't know of anyone trying to do so.
Concorde and other supersonic aircraft also have to, for similar reasons, slow the speed of engine inlet air below supersonic speeds before combustion.
I believe the Scramjet principle does not require the airstream to be slowed below supersonic speeds.
(At the time, I knew a 135 pilot who said the really loud ones were the result of injecting water spray into the combustion process to boost thrust on launch.)
That may be true. I'm not sure if I have heard one with water injection or not.
Interestingly, I know that the huge amount of water they spray into the launch pit for the Space Shuttle is to dampen sound, whereas I thought it had something to do with keeping things cool. Interesting that changing when you dump in the water has the opposite effect on the noise level.
Actually, they DID correct this vulnerability.
I live next to Tinker AFB, and our KC-135s are loud, but nowhere near as loud as the B-52s that occasionally take off.
I never got to hear a Concorde, though.
Right. Just like we prohibit our airlines from buying Airbus, Embraer, Bombardier, Saab, etc, and won't let those planes land here.
I mean really, if we wanted to help our struggling airplane manufacturers, wouldn't it make more sense to stop the manufacturers that sell hundreds of airframes, rather than the one that will sell maybe 50 if they're lucky?
Cheer up. We have a 100+ year supply of coal, even factoring in the current growth of energy use. Unfortunately, coal is useless in airplanes, but probably what we need to do more or less immediately is to start running boats, electric plants and other things that CAN burn it on coal. And use Oil for airplanes and other things. Also, there is always nuclear energy, which I'm sure the treehuggers will take more kindly too when the oil burning electric plant shuts down, and they can no longer run their espresso machines.
The problem really comes down to the fact that companies are unwilling to pay for R&D. Bell Labs used to pour billions into R&D and this made them one of the largest contributors to innovation in the 20th century. Companies that pour huge amounts of money into R&D reap huge long term profits. However, short term profits and short term cash reserves are sacrificed in order to do this. Publicly held companies are at the mercy of us, the public, who demand consistent short term profit and as such, can not really be blamed for cutting R&D budgets. Certainly a bird in the hand is worth two in the bush. But is a bird in the hand better than a hundred in the bush? A thousand? A million? At some point, your expected return from firing randomly into that bush is higher than one bird.
Unless we as Americans wake up to the necessity of R&D and thinking in the long term, we are going to end up with no innovation and eventually no jobs. Greed is going to make us go broke.
The spin of the Earth is definitely a factor, however, the Earth is not just going to spin under you. You still have the atmosphere to deal with. In some locations, it runs counter to the rotation of the Earth, and in other locations, it runs with (and faster than) the rotation of the Earth. At very few place and for very short lengths of time, does any part of the atmosphere move with the rest of the planet.
The internet/voip and other communication mediums have obsoleted the necessity for face to face contact and the costs associated with business travel.
Uh, huh. Why is it that most of the jobs on Dice.com rquire 25% to 100% travel? And why do very few companies allow you to telecommute?
One more problem with supersonic jetliners is terrorism. If the emir's warriors got hold of an M2+ plane, it would be virtually impossible to stop, unlike subsonic planes, as fighter jets couldn't catch it in time. And when it hits...
Fighter jets would not be able to catch a conventional jet plane in time either. They didn't even catch up to a Cessna 172 until it was nearly to the center of the ADIZ around D.C.
A single Concorde impacting at top speed (1.1M at low altitude or twice of those B767s) would have probably gone right through BOTH the north and south towers of WTC!
Which, as it turns out, would have been better for everybody, because at least the towers would still be standing.
The FAA prohibits supersoinc flight over US Soil @ any altitude without prior special approval.
That's interesting since the FAA has no jurisdiction over altitudes above 60,000 feet.
Also, this applies only to civilian craft, as the military happily creates sonic booms all the time, as does the space shuttle.
The moon is already creeping away from us slowly and thus reducing the tidal influence.
The moon's mass is within an order of magnitude of the Earth's mass. Taking resources off of the moon is similar to taking resources off of the earth. It would take a darn long time for it to become significant.
History makes it pretty clear that when you get Americans, resource interests, and weapons together in one place, but there is already someone else at that place, you can be sure that an application of Rule #2 is coming soon.
You shouldn't use History to try to prove something about Americans. We've only been here a few hundred years. Our nhumber of landgrabbing attempts pale in comparison to those done in European, African, and Asian history.
Well, there's certainly no clouds, but just like earth, there is night and day on the moon. A lunar day is about 2 weeks in our time. There is no sunny side.
Not really. They poured all kinds of fuel inside of it, and strapped it next to a huge tank of liquid oxygen, and then stuck two solid rocket fuel boosters on the outside of the tank, but they still only got it to blow up once out of 117 missions.
(The re-entry mishap was not an explosion)
Where are you going to get this inexhaustable supply of propellant gas?
Actually, since the airplane industry likes to use "passenger*miles" to show how much safer they are than driving, NASA could use the same calculation for the shuttle and probably end up proving the shuttle to be MORE safe than an airplane.
The last sentence was intended to inspire students to dream about ever greater achievement and exploration. It read, "Who knows, someday man may even reach the moon."
Sadly, that book is no longer outdated. Who knows, someday maybe that book will be outdated again.
I am man enough to admit that when I saw the Saturn V in the museum at NASA, and thought of what we had once done, and can no longer do, I got tears in my eyes.
I say just design a re-usable launch vehicle that can transport one standard shipping container (the ones they use to ship freight on boats) and all you have to do is design a container for each kind of launch...
Those containers are designed to stack X high and are thus very strong and very heavy. I like your idea, but would say that we should make it where it doesn't need to have stackable strength at all. More like the ones that are used in wide body airplanes (and even those can be stacked a couple high).
When I toured the NASA facility in January, they had a long thick wire running from the gantry down to the ground quite a distance away. The tour operator said that was in case they needed to evacuate the platform in an emergency. I think they got into some sort of vehicle which would run down the wire at something like 50 MPH.
Don't be silly. Dead people are an affected class. They are much more likely to vote Democrat.
how a timeless entity can act to create something given that he has no time to move in
This shows why opponents and proponents of creationism can never convince each other. Opponents keep wanting to try to understand a creator in terms of universal components of time and material. You ask how a creator could create the universe when he has no time to move in. A few posts up, someone asks how there could be the universe AND be something else (that being the creator). In terms of science, there can't. Nothing can happen without time, and everything is made of matter. Nothing can exist outside of the universe, which is the sum of all matter.
Scientifically, this is true. But I have no problem believing that a creator created the universe, time, nature, scientific principles and so forth, but having created those things doesn't mean that he is limited by those things. He doesn't have to operate in time, doesn't have to be composed of matter, etc. Science can prove that such a creator can not exist in this universe, however, the scientific rules and properties that govern the creation do not necessarily apply to the creator.
That hypothesis makes the assumption that the Intelligent Designer is part of the creation and therefore had to be created Himself. That is not what creationists believe.
Further, going one step lower, your argument could be used as a question to show that Legos don't have to be intelligently designed. They could just exist by themselves.
Except of course, that Legos and the designers of Legos are part of the universe, whereas creationists contend that the creator created the Universe and is NOT part of it.
"It's no Hitchhikers Guide to the Galaxy..."
He died of having AIDS. Cancer killed him.
It is true that AIDS itself does not kill you, but prevents your body from fighting off the actual common causes of death such as pneumonia. However, if someone doesn't actually HAVE AIDS, then you can't say that they died of having AIDS, but something else killed him. For example, Graham Chapman denied having AIDS, and there is no reason for him to lie, since he was openly homosexual. We must assume he was telling the truth and did not have AIDS. Therefore, he died of cancer, and cancer is what killed him.