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Will Spacecraft ever Go Faster than the speed of Light?
Various - See Text ^
| 16 FEB 2003
| Various
Posted on 02/16/2003 2:16:44 PM PST by vannrox
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To: vannrox
Your neutrino sources are rather dated. They figured out where the missing solar neutrinos are. The "missing" ones change flavor on the way to earth. IIRC, some experiments show a very small positive (not complex) mass for neutrinos as well. Maybe ping Physicist?
To: ffusco
The speed of light actually changes every year,IE they get a better estimation of the speed.Is this true?
To: Fractal Trader
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|
AnalogScience Fiction & Fact Magazine
"The Alternate View" columns
of John G. Cramer
Subject Index |
Menu of Subjects
[Each underlined column title is a link to that column; click on the title to go there.]
Group 1 - Cutting Edge Science
Group 2 - Quantum Mechanics
Group 3 - Neutrinos
Group 4 - Cosmology and Astrophysics
Group 5 - Gravity and General Relativity
Group 6 - Wormholes
Group 7 - Mega-Projects
Group 8 - Space Drives
Group 9 - Evolution and Catastrophe
The Alternate View
Column Title |
Subject of Column |
Analog
Issue |
Column
Code |
| The Pump of Evolution |
The Fermi Paradox and catastrophes |
01/86 |
AltVw11 |
| Dinosaur Breath |
Cretaceous air trapped in amber |
07/88 |
AltVw27 |
| Killer Asteroids and You |
Earth-orbit-crossing asteroids |
01/92 |
AltVw50 |
| The "Rare Earth" Hypothesis |
A new book by an astronomer and a geophysicist argues that complex life must be very rare in our galaxy and our universe. We may be alone. |
09/00 |
AltVw102 |
Group 10 - Communications and Virtual Reality
Group 11 - Flashes in the Pan - Things That Didn't Work
Group 12 - Science Policy
The Alternate View
Column Title |
Subject of Column |
Analog
Issue |
Column
Code |
| The Territoriality of Space Exploration |
Guest Editorial: Should the USA have claimed the Moon as territory? |
11/81 |
Analog-2 |
| The Alternate Who???? |
1st Alternate View column - Introduction of the author |
07/84 |
AltVw00 |
| The Retarding of Science |
AARSE - American Association for the Retardation of Science and Engineering (satire) |
13/84 |
AltVw04 |
| Dyson on Space |
Freeman Dyson's views on the space program |
13/88 |
AltVw30 |
| Science and SF in Japan |
Report on a trip to Japan |
04/93 |
AltVw58 |
| Science Policy: The Parable of the King and the Grain |
The politics of scientific decisions |
08/93 |
AltVw60 |
| CERN in Transition |
The new 33 TeV lead beams |
06/95 |
AltVw72 |
| 2001, Then and Now |
How and why the year 2001 as depicted in the Stanley Kubrick film differs from the the reality of the year 2001? |
07/01 |
AltVw107 |
Note 1: Month "13" in the issue list above indicates the Mid-December issue of Analog.Note 2: The "Alternate" of the column title refers to the fact that they appear in alternate issues of Analog, originally alternating with columns by the late G. Harry Stine and more recently with columns by Jeffery D. Kooistra .Note 3: Recent columns may not be provided with links because they have not yet appeared in Analog, which holds first serial rights for their publication.
43
posted on
02/16/2003 4:24:09 PM PST
by
vannrox
(The Preamble to the Bill of Rights - without it, our Bill of Rights is meaningless!)
To: Physicist; AFPhys
I think I read that as an object approaches the speed of light, it increases in mass. Supposedly one reaches infinite mass at c.
And if theorized faster-than-light particles called tachyons exist, why haven't we ever detected Cerenkov radiation in a vacuum?
44
posted on
02/16/2003 4:25:33 PM PST
by
petuniasevan
(Free Republic of Katzenellenbogen at NationStates.net)
To: vannrox
I would really rather have a halodeck,(sp)now that would have possibilties!!
45
posted on
02/16/2003 4:29:05 PM PST
by
oregon conservative
(I'm in Oregon, shields up and phasers on stun!)
To: vannrox; All
Sorry to bring all you starry-eyed dreamers down to earth, but the real limiting factor in all of this will be economics. Any travel even approaching -- not to mention exceeding -- the speed of light will require enormous amounts of energy. Last I checked energy still cost money. Even if we finally get fusion reactors, energy will not be "free". The economic fact of life is that resources are not infinite, and thus they do have a cost. There is no such thing as a free lunch. So the question thus becomes: what economic benefit will be gained by tooling around the universe to pay for the enormous quantities of energy that will need to be allocated for this project?
To: petuniasevan
I think I read that as an object approaches the speed of light, it increases in mass. Supposedly one reaches infinite mass at c.Well, no, because then photons would have infinite mass, but they don't.
And if theorized faster-than-light particles called tachyons exist, why haven't we ever detected Cerenkov radiation in a vacuum?
Because tachyons do not have an electromagnetic charge. Similarly, many neutrinos pass through the air in your room every second at a speed faster than the local speed of light, yet they do no emit Cerenkov radiation.
To: petuniasevan
Early X-Planes
At the end of World War II, the United States operated some of the most advanced aircraft in the world, such as the B-29. But the pace of change during the war had been so fast that it became clear to many top scientists and military leaders that unless the United States actively sponsored advanced aeronautics research, it could quickly fall behind. As a result, in 1945 the U.S. Army Air Forces (which became the U.S. Air Force in 1947) and the National Advisory Committee on Aeronautics, or NACA, began the first of a series of experimental aircraft projects, many of which were designed to develop technology for high-speed flight.
These soon became known as X-planes. While prototype and experimental aircraft were not new, the X-planes were significant because they were solely intended to develop technology in general, not lead to operational aircraft. The first aircraft produced by the joint team was the XS-1. The "S" stood for supersonic and was dropped early in the program. The X-1 was the first crewed vehicle to break the sound barrier. It was built by Bell Aircraft Company. Its fuselage was modeled on a 50-caliber bullet because that was the one shape that aerodynamics experts knew did not tumble at supersonic speeds. It had straight, very thin wings. It was powered by a rocket engine and dropped from the belly of a B-29 bomber. Its first flight was in January 1946. On October 14, 1947, the X-1, piloted by Captain Charles (Chuck) Yeager reached a speed of 700 miles per hour (1,127 kilometers per hour) while at 45,000 feet (13,716 meters), breaking the sound barrier. The X-1 proved that an aircraft could be controlled at speeds faster than the speed of sound, Mach 1. It led to several aerodynamic advances that were quickly incorporated into U.S. fighter aircraft designs.
The X-1 actually had a conventional tail with elevators for pitching the nose up and down. However, at high speeds, a shockwave formed on the tail surfaces near the hinge for the elevators, rendering them useless. But the X-1 also had a system for raising and lowering the entire tail a few degrees to adjust the trim of the airplane in flight (to enable it to fly level). Yeager and the X-1 flight engineers proposed using this system instead of the elevators at high speeds to control the airplane. It worked and this lesson was secretly incorporated into American fighter planes at the time, giving the United States a technological edge over Soviet, French, and British aircraft for several years. Today, all supersonic aircraft use all-moving tail surfaces. After the success of the X-1 program, the Air Force and NACA teamed up again to develop the second generation X-1, which was intended to fly at twice the speed of sound, or Mach 2. Four aircraft were planned. The X-1A had its first flight on July 24, 1951. It and its sister craft the X-1B established new speed records, eventually reaching a speed of Mach 2.44 (1,650 miles per hour) (2,655 kilometers per hour) and an altitude of 90,440 feet (27,566 meters).
The Bell X-1E soon followed these earlier aircraft with its first flight in December 1955. Although it did not achieve speeds or altitudes as high as the X-1A or X-1B, the X-1E proved that an extremely thin wing could be used on supersonic aircraft. This research led to the Lockheed F-104 Starfighter interceptor aircraft. (The X-1C was canceled before completion. The X-1D was destroyed before it could make its first powered flight.)
In June 1952, the Bell X-2 had its first flight. The X-2 was equipped with a pointier nose and more powerful rocket engine than its predecessors. It was designed to reach speeds in excess of Mach 3 (2,094 miles per hour). At such high speeds, the friction from air brushing against the aircraft heats its skin to high temperatures. The X-2, therefore, had to be made of advanced lightweight heat-resistant steel alloy. The X-2 reached a record altitude of 125,907 feet (38,376 meters). Research on the X-2, including new construction techniques, contributed to the development of advanced materials for high-speed aircraft such as the XB-70 bomber and the SR-71 spyplane. The Douglas X-3, which first flew in 1952, was not as successful as its predecessors. Unlike the earlier aircraft, it was not rocket-powered or dropped from the belly of a bomber, but instead took off from the ground like a conventional aircraft with jet engines. It had a short, thin wing that did not generate much lift except at high speeds. This meant that it did not lift off from the runway until it was traveling very fast, which caused its tires to overheat. As a result, several tire companies developed high temperature materials for aircraft tires.
Even the failure of an X-plane to achieve its goals was useful. The Northrop X-4, which flew from 1948 to 1953, proved that tailless aircraft were unsuitable for high-speed subsonic flight (under Mach 1). Other X-planes were developed to conduct various flight research. Some, such as the X-15, developed soon after the earlier X planes, were very successful whereas others demonstrated that certain technologies were essentially dead-ends The X-planes that did fly were usually equipped with multiple recording instruments, some of which radioed their data to the ground. They often flew numerous flights, each one methodically advancing the flight envelope and providing insight into advanced aerodynamics, engines and materials. Most X-planes have been developed by either the NACA or the National Aeronautics and Space Administration (NASA) in partnership with the military, usually the U.S. Air Force. Later on, the "X" designation was used in different ways. In one case, the designation was used to mislead people into thinking that a secret spyplane project (the X-16) was actually an experimental aircraft. In other cases, the X designation has been applied to early prototype versions of operational aircraft. But initially, the title "X-plane" indicated that an airplane was built solely to demonstrate and improve aviation technology.
The Speed of Sound and Mach Numbers
The Mach number (M) refers to the method of measuring airspeed that was developed by the Austrian physicist Ernst Mach. It is used to indicate flight velocities in high-speed flight and is related to the speed of sound. The actual speed of sound varies depending on the altitude above sea level because sound travels at slightly different speeds at different temperatures, and the temperature varies according to altitude. At sea level, the speed of sound is about 761 miles per hour (1,225 kilometers per hour). At 20,000 feet (6,096 meters), the speed of sound is 660 miles per hour (1,062 kilometers per hour).
If an aircraft is traveling at one half the speed of sound, it is said to be traveling at Mach 0.5. A speed of Mach 2 is twice the speed of sound. Because the speed of sound varies, a particular speed at sea level expressed as a Mach number would be faster than the same speed at 30,000 feet (9,144 meters), which would be faster than the same speed at 40,000 feet (12,192 meters). In other words, Mach 2 at sea level is a greater number of miles per hour (or kilometers per hour) than Mach 2 at 30,000 feet, which is a greater number of miles per hour than Mach 2 at 40,000 feet. When an aircraft reaches Mach 1, it is said to "break the sound barrier." The following breakdowns have been generally accepted to classify speeds:
M less than 0.8 subsonic
M = 0.8 to 1.2 transonic
M - 1.2 to 5.0 supersonic
M greater than 5.0 hypersonic
A "critical Mach number" is the speed of an aircraft (below Mach 1) when the air flowing over some area of the airfoil has reached the speed of sound. For instance, if the air flowing over a wing reaches Mach 1 when the wing is only moving at Mach 0.8, then the wing's critical Mach number is 0.8.
48
posted on
02/16/2003 4:38:55 PM PST
by
vannrox
(The Preamble to the Bill of Rights - without it, our Bill of Rights is meaningless!)
To: pabianice
Nice!
49
posted on
02/16/2003 4:42:30 PM PST
by
buffer
To: petuniasevan
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Designing the X-1
Powering | Controlling | Safety | Flying
Breaking the Sound Barrier | Reverberations
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Goodlin: I guess one could say that the X-1 was a bullet with wings on it. It was a very small aircraft. It was only 31 feet long and had a 28-foot wingspan. However, it was built extremely rugged and it was possible to withstand enormous forces. The Bell X-1 was really designed the way it was because the designers at Bell examined a 50-caliber bullet flying at supersonic speed. And it was a very stable bullet aerodynamically speaking. And so they decided to build the X-1 in the form of a bullet with wings. And that is what the X-1 really turned out to be. It was only 31 feet long, it had a 28-foot wingspan. But the fuselage was shaped like a bullet.
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Beeler: The fuselage was shaped like a bullet, and the next thing we saw it had straight wings at about the mid-section and then the tail was elevated high, and there was a reason for all of this. The bullet shape was because of munitions research done many years before. The straight wing, we advocated that basically because of flight tests we did with a World War II fighter. The tail was high -- we wanted that to wave in the wake from the turbulence from the wing. And then I remember one comment said, "Yeah, that looks great -- how about the pilot?" And he didn't have a bubble canopy anymore. He couldn't see to the rear. And he had this high slope, aerodynamically it was perfect, but he was stuck behind that. And the next thing is well, how does he get out? Well, by this door. And no seat ejection. And then if he climbs out successfully, and there is a wing right behind him that could make hamburger out of him, and if that didn't do it, it would take up and hit in to the tail. So that was kind of a joking type of a thing. But aerodynamically, particularly if it was going to be rocket-powered, it looked the most aerodynamically clean configuration I think that we could come up with.
Powering the X-1
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Yeager: Basically the X-1 was a pure rocket. It burned liquid oxygen and a mixture of five parts alcohol to one part water. You know, we'd been fooling around with jets. Jets engines didn't have the thrust to push the airplane into the region of the speed of sound or beyond.
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Beeler: Personally I had some reservations about a rocket, when you see them operate. Because it's like a small explosion. But it would get you to the area of interest a heck of a lot quicker and I'm not sure that we knew that much about a jet engine -- the time to get there and all the aerodynamic problems of getting the air to the engine. The rocket appeared to be the simplest.
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Goodlin: Well, I first operated the rocket engine in a special test cell at the Bell facility at Niagara Falls. And I must say that it was a very unnerving experience because the rocket engine made such an ungodly noise and shook the whole building to its foundations. And that was the most worrying thing about the entire X-1 program was the rocket engine. I wasn't worried about the air frame, but the rocket engine with its volatile fuels, which were liquid oxygen and ethyl alcohol, gave one some concern.
NOVA: What was your concern?
Goodlin: That we would have an explosion in the rocket engine.
Controlling the X-1
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Hear Beeler
via RealAudio |
Beeler: Well, when you reach the -- near the speed of sound, you develop what we call a shock wave. And behind that shock we call it a dead water region. In other words anything that tried to operate behind the shock would become extremely ineffective -- almost no effectiveness at all. And this occurred in some of the fighter airplanes when they dove at very high speeds from World War II, and we knew it would happen on the X-1 and it did. But we had a backup in which we had installed an adjustable tail plane in which we could use that, you might say, as an emergency device in which it would give the pilot longitudinal control. And it worked.
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Hear Yeager
via RealAudio |
Yeager: When we got the airplane up to 94 percent of the speed of sound and I'm sitting out there and I decided to turn the airplane I pulled back on the control cock, nothing happened, the airplane just went the way it was headed. And I said, man, we've got a problem. So I raked the rockets off, and jettisoned the liquid oxygen and alcohol and came down and landed and we got the engineers together and we had a little heart to heart talk. I said, "We've got a problem -- because the airplane may pitch up or pitch down. I've lost the ability to control it."
Safety and the X-1
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Hear Goodlin
via RealAudio |
Goodlin: As a matter of fact I was unhappy about the X-1 from the escape potential because it was very badly designed from that standpoint. The entrance hatch was on the side directly in front of a very sharp wing. And I felt that if one had to bail out of the airplane in an emergency, if one didn't hit the wing, one would hit the horizontal tail surface, and therefore I thought it was a very dangerous airplane.
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Hear Yeager
via RealAudio |
Yeager: Colonel Boyd, you know, sort of evaluated everything and ended up calling me in and said, you know, if you get the X-1 program we... pay attention and fly safe and don't bust your fanny. And I said, "Yes sir." And that was about the end of it. And then about a month later, after I'd been assigned to the X-1 program he called me back in and said, "You know, we've got a problem." He said, "I wanted a pilot who had no dependents." I said, "Hey, Colonel Boyd," I said, "I, yeah, I'm married and I, I've got a little boy, and I, I think that makes me more careful." And that worked out. He said, "Well, OK, be careful."
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Hear Goodlin
via RealAudio |
Goodlin: I can't imagine why they got to the point of building the airplane without having proper escape provisions. I don't know how that ever happened, but I was not involved in designing the airplane.
NOVA: Isn't that a sign that the, the project is being made more important than the lives of the pilots who are being asked to test it out?
Goodlin: Of course. But this happens all the time in the military-industrial complex.
NOVA: So did it make you feel almost like a pawn in the game?
Goodlin: Well, I think at that stage in my life I wasn't thinking about analyzing the military-industrial complex. Today I do. But at that time I was just a, a very eager adventurer, and I loved flying. And being involved in the hottest aviation project in the world causes one to overlook the basic fundamentals, such as pilot safety.
NOVA: What about the dangers in flying this plane?
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Hear Yeager
via RealAudio |
Yeager: That's immaterial. Duty above all else. See, if you have no control over the outcome of something, forget it. I've learned that in combat. You know, you know somebody's going to get killed, you just hope it isn't you. But you've got a mission to fly and you fly. And the same way with the X-1. When I was assigned to the X-1 and, and was flying it I gave no thought to the outcome of whether the airplane would blow up or something would happen to me. It wasn't my job to think about that. It was my job to do the flying.
Flying the X-1
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Hear Goodlin
via RealAudio |
Goodlin: Well, it was a very exciting experience as you know. The X-1 was carried aloft in the bomb bay of a B-29. And the procedure of going down the ladder and crawling into the X-1 at 8,000 feet and then sealing the door and being carried still higher to 28,000 feet, it was rather exciting, you know. I had no apprehension about it because we had no rocket fuel on board. And so when we got to altitude and went through the normal procedure of countdown and here I was in a very tiny cockpit and it was very dark, and all of a sudden when the X-1 was released from the B-29 I was in bright sunlight and I could hear nothing, it was so silent. And it took my eyes awhile to become accustomed to the daylight. And of course as one was without any power it was necessary to immediately examine where our position was in relation to the airport because one had to always stay within the landing distance, or gliding distance of the lake bed -- and at the same time put the aircraft through the maneuvers, stall tests and the stability and control tests. And it was all very exciting but it went off extremely well. And I landed on the lake bed without any difficulty.
It was a very delightful airplane to fly, as a matter of fact. It had the, the handling characteristics of a fighter plane. And it was very agile. I had no complaints about the flying qualities of the airplane at all. The serious points on the X-1 were the rocket engine and those escape provisions.
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Hear Yeager
via RealAudio |
Yeager: Since the airplane was liquid rocket powered it only had two and a half minutes of power under full thrust. And consequently we decided to drop it from a B-29 mother-ship to conserve fuel. And that's the way every flight, with the exception of one, was launched from a B-29 or a 35... at around 25,000 feet. After drop, clear of the B-29 you'd fire off one, two or three or four chambers of the rocket motor. They were not throttle-able. You could just select the chambers either on or off, and you ran it until it ran out of fuel. And then you dead sticked into, into Roger's Dry Lake.
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Hear Goodlin
via RealAudio |
Goodlin: So then when the drop took place, one would sort of count to ten and hit the rocket engine control. And we had four positions on the rocket engine for each rocket chamber. And to fire up one rocket. And of course the first time I did it, it was like being hit in the back with a lead boot. And the aircraft accelerated very, very rapidly. And of course as one increased the thrust by adding more rocket positions -- actuating more rocket positions -- well, the aircraft could go very fast indeed, and quickly leave behind the B-29 and the chase plane. And of course the first time I did that, why shortly after I accelerated, the fire warning light came on. And that caused the adrenaline to flow. And so I immediately shut off the rocket motor and called Dick Frost on the radio, who was flying the chase plane, and asked him if he could see any fire -- that my fire warning light had come on. And of course he was way behind me and said he couldn't see any evidence of fire. But after I had slowed down, why he could pull up behind me and he could still see no evidence of fire, but my fire warning light was still on. So I dumped the rest of the fuel and went back to the landing area and set the airplane down. And sure enough we had sustained a rather serious fire in the engine compartment.
NOVA: When the fire warning light came on, describe your feelings.
Goodlin: Well, it's a rather hopeless feeling because one can't see behind from the X-1 cockpit. And so one can only assume the worst, that there's a fire raging there. And so all I could do was wait until Frost could pull up behind and tell me that there was no, absolutely no fire visible. But obviously one thinks all sorts of things, and of course I was concerned because of the lack of escape provisions in the airplane.
Breaking the Sound Barrier
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Hear Yeager
via RealAudio |
Yeager: The flight, October 14, fell on a Tuesday. And I think Glennis, my wife and I, were over at Pancho's having dinner, and we went horseback riding. I ended up breaking a couple of ribs when the horse hit a fence and tumbled. And when Monday come along, I got Jack Ridley and said, I've got a problem, I've got a couple of broken ribs, I can't -- I don't think I can close the door with my right side, my right arm, and he, that's when he got the broomstick and I stuck it in with my left arm and closed it. And once we found that out, as far as getting into the airplane -- it was very, oh, painful, because you have to bend up double to slide in. Once I got in it was no problem.
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Hear Yeager
via RealAudio |
Yeager: We didn't -- we had no idea anything was going to happen. There was some indication on the previous Friday's flight that we had a very large error in our Mach meter. Otherwise we were indicating about 9.3, or .94 Mach number which was 94 percent of the speed of sound. There's some indication when NACA reduced the data from our instrumentation in the airplane that we're going a lot faster than indicated. And there was some, a little bit of excitement that said, hell, we, it looks like we've, we've been up to about 99 percent of the speed of sound. And we still are in buffeting and the airplane is shaking quite a bit. You know, they weren't sure, because you, you're in an area where very little is known. They had no wind tunnel data, nothing, and everything was trial and error. And there was some indication that we had been going faster than we had thought. But we had no idea what was going to happen on the next flight. And when we got the airplane up to oh, about 96 percent of the speed of sound indicated, that was almost Mach 1. And when we went a little faster the Mach meter went off the scale. And ah, when it did all the buffeting smoothed out, because of the supersonic flow of the whole airplane. And even I knew we had gotten above the speed of sound. And I let it accelerate on out to about 1.06 or 1.07, seven percent above the speed of sound, and the airplane flew quite well. And I got some elevator effectiveness back, but not very much.
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Hear Beeler
via RealAudio |
Beeler: And then, The best I remember now, we knew the rocket was on, and we really didn't get anything back from Chuck. You'd have to look at the telemeter data if we did. But as far as us listening, the next thing is that Chuck says, I think he did make a remark on his longitudinal control, I forgot. But the next thing my Mach meter jumped. And then at that time we got a bang. And personally, I have to say, I didn't know anything about bangs. I didn't know anything about it. Someone may say they knew about it from gunshots and that sort of thing, but to people around there, we got a bang.
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Hear Yeager
via RealAudio |
Yeager: Your emotions on something like that -- you're too busy staying on top of the dome regulators and watching the chamber pressures and doing everything you're supposed to. And you might say I was a little bit disappointed it didn't blow up. That's about the only way to say -- hell, it's a piece of cake.
Reverberations
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Hear Yeager
via RealAudio |
Yeager: A lot of the news media were digging, you know, and I'm sure the intelligence people from the Soviet Union and the French and the British were all digging. Then after about seven months, you know, we satisfied their digging. We released the fact that we had flown faster than the speed of sound. That, you know, that satisfied their digging. What they didn't know was how we had done it.
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Hear Beeler
via RealAudio |
Beeler: When Chuck made that supersonic flight it opened up a big wide door and everybody could jump in with all these applications. And that was one -- that probably is the biggest impact as far as the world economy -- people in one world type of thing.
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Hear Yeager
via RealAudio |
Yeager: Obviously the reason we kept it classified was to keep the rest of the world from finding out about a flying tail that's necessary to control the airplane through the speed of sound. It resulted in a kill ratio of 10 to 1 between the F-86 and the MiG 15. That one simple thing, of putting a flying tail on the F-86, because we knew that it would dive to the region of the speed of sound, and it pitted it against the MiG 15 in Korea, in 1951, '52, and '53, and we had a kill ratio of 10 to one. And when I flew the MiG 15 over there for the first time I was amazed, because it was a good airplane, just like the Hawker-Hunter was or the MD-452, that Dassault built for the French air force, but it didn't have a flying tail on it.
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50
posted on
02/16/2003 4:47:43 PM PST
by
vannrox
(The Preamble to the Bill of Rights - without it, our Bill of Rights is meaningless!)
To: Physicist
Wouldn't there be a problem with "space junk?" It's mind-boggling to think of even a tiny piece of dust slamming into a spaceship at speeds even close to 186,000mps!
51
posted on
02/16/2003 4:49:36 PM PST
by
scott7278
(Peace had it's chance, now it's bombs away!)
To: vannrox
I, for one, would not want to become a tunneling photon until my kids are in college :^D
52
posted on
02/16/2003 4:55:38 PM PST
by
a_Turk
(Ready? Set? Wait!!)
To: vannrox
What a terrific effort, vannrox. VERY interesting; greatly appreciated.
It's been decades since I was purported to be a physics major in college, but I can only guess that such a compendium would be invaluable to many, many current students of physics.
Bookmarked and bumped.
[As an aside, I certainly cannot prove it, but I remain convinced that we will eventually find ways to achieve FTL speeds and somehow keep Einstein's work intact. Don't ask me how.........just a gut feeling.:) ]
To: MHGinTN
"Speed is a function of distance traveled in unit time, where background time is considered to be invariant. If every mass is a complex of temporal and spatial quantity, then the possibility of 'different' temporal variable for differerent masses is very possible and is, in fact, the blaise explanation of neutrinos and their 'rest mass'. Put another way, if the universe of our experience is a volumetric/present realm, the masses within that realm may have present, past, or future temporal orientation, combined with linear, planar, and/or volumetric spatial orientation. "Taking a thought excursion, if one could 'view' the spacetime continuum in which our world exists, from outside that realm, what would be 'observed' would be a volumetric/past-->future realm, in which exist linear, planar, and volumetric spatial phenomena ... so, why not past, present and future temporal phenomena, also, within the realm 'observed'?"
Beats me.
I think you should read Julian Barbour's The End of Time and explain it to me when you're done. I read it twice and it's blinking well baffling, mate.
BTW:
blasé
SYLLABICATION: bla·sé
PRONUNCIATION: blä-z
ADJECTIVE: 1. Uninterested because of frequent exposure or indulgence.
2. Unconcerned; nonchalant: had a blasé attitude about housecleaning.
3. Very sophisticated. ETYMOLOGY: French, from past participle of blaser, to cloy, from French dialectal, to be chronically hung over, probably from Middle Dutch blsen, to blow up, swell.
54
posted on
02/16/2003 5:15:57 PM PST
by
boris
To: boris
How did you make that little mark over the 'se'? ... Explian The End Of Time to you! I couldn't explain Prigogine's End Of Certainty to someone, so the time thingy would be out of the question. [I can't achieve Pioncare resonance for the job. ... I know, I need a little dash up there over the name, but ...]
55
posted on
02/16/2003 5:27:09 PM PST
by
MHGinTN
(If you can read this, you've had life support from someone. Promote Life Support for others.)
To: Stefan Stackhouse
"Sorry to bring all you starry-eyed dreamers down to earth, but the real limiting factor in all of this will be economics. Any travel even approaching -- not to mention exceeding -- the speed of light will require enormous amounts of energy. Last I checked energy still cost money. Even if we finally get fusion reactors, energy will not be "free". The economic fact of life is that resources are not infinite, and thus they do have a cost. There is no such thing as a free lunch. So the question thus becomes: what economic benefit will be gained by tooling around the universe to pay for the enormous quantities of energy that will need to be allocated for this project?" Comment 1: If the human race does not destroy itself or encounter a cosmic catastrophe such as an asteroid, we will have to pack our bags and relocate eventually anyhow (or our descendants will). The Sun cooks everything in about 8 billion years.
Comment 2: "If any of these schemes were feasible, intelligent ETs would have reduced them to practise millions of years ago. We do not observe their traffic; hence either there are no intelligent ETs or none of these schemes are feasible."
Comment 3: Robert Bussard, in Acta Astronautica, described a fusion ramjet operating using the interstellar medium as propellant (rare hydrogen atoms) which potentially can reach very high fractions of "C". Nobody knows how to build a fusion engine--yet.
Comment 4: Neglecting Einstein, a kilogram of mass at "c" has 4.89 times ten to the 17th power joules of kinetic energy. It turns out that one "gee" acceleration is 1.03 light years per square year. If one could accelerate at one "gee" for one year, one would be "near" light speed and 1/2 light year from earth. A year is about 3.15 times ten to the seventh seconds. Thus the kilogram would require about 1500 megawatts delivered continuously for one year at 100% efficiency and directed into propulsive power to reach near "c". To account for various inefficiencies, call it 2000 megawatts. Roughly the output of two large terrestrial generating plants--per kilogram.
If one plans to take the propulsion along for the ride, the problem is to reduce these power plants to a small fraction of a kilogram in mass and volume. (Otherwise there is no room for payload, crew, structure). Scale up as necessary until you hit "Enterprise". Something like compressing the Sun into a small space.
Human beings are not (yet) able to deal with these energies, powers, durations.
Comment 5: One question I have saved up for the Almighty is: "Why the heck did you put everything so bleeping far apart?" It is almost as if the Universe is designed to prevent travel/contact/exploration...
--Boris
56
posted on
02/16/2003 5:28:05 PM PST
by
boris
To: RadioAstronomer
Ping-a-ling ... thought you might find this thread of interest. Stunning links herein
57
posted on
02/16/2003 5:28:48 PM PST
by
MHGinTN
(If you can read this, you've had life support from someone. Promote Life Support for others.)
To: vannrox
That's so very three dimensional.
58
posted on
02/16/2003 5:29:36 PM PST
by
TheHound
To: luv2ndamend
I'm not a physicist but I imagine that all measurements are getting more precise.
59
posted on
02/16/2003 5:37:13 PM PST
by
ffusco
(Omni Gaul Delenda Est!)
To: vannrox
None of the articles which you have listed reflect any of my interests and knowledge. I would respectfully suggest that you explore other avenues of investigation than a cousin of "Omni" magazine. Even google on the keywords which I mentioned would get you much further than this balderdash which you have suggested.
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