In recent TV news in early February 2017, a Stealth ship, a Destroyer, remarkably like the one I describeed to the Pentagon in 1990, is shown, where the Reporter said that it may be about to sail to South Korea. I wish the Government or the Pentagon would acknowledge appropriate credit when they essentially STEAL an invention without indicating proper credit. I understand the ultra-secret nature of Stealth technologies, but now that they are SHOWING their new Stealth Ship in the news, I would think it would be safe to mention that I had presented a very similar technology to their Brass 27 years earlier.
As it happened, as a Theoretical Physicist, I had then been studying Police Radar, and I had discovered a slightly different application of the Radar technology. That doesn't really apply here, except for having done extensive study of how Radar works. In that case, I knew that all of the Police Radar guns were designed to only display speeds of less than 140 mph (as any speeds beyond that are both impossible for most vehicles and also irrelevant for Police purposes). My Police Radar devices were NOT electronic, like dozens of popular products then were, but they simply produced a radar echo which made it seem that the offending vehicle was moving faster than 140 mph, and so the Police Radar Gun simply 'blanked out' for not being able to display the speed which seemed to be detected. It was amazingly effective, and in 1989, a good friend who was a Police Officer partipated in a demonstration along a Frontage Road where he was shocked that my 45 mph car consistently caused his Police Radar gun to 'blank out'. But that technology was rather different from this slow ship intended device.
This presentation was first placed on the Internet in July 1999.
Soon after an American ship in the Mid-East had been hit and damaged by an Exocet missile, I invented a method for hiding American ships from enemy radar. Enemy radar-guided missiles such as Exocets would be less successful in attacking an American ship protected by this invention.
Interestingly, several years earlier, I had figured out that a very angular, squarish structure of an aircraft would similarly provide radar safety, by reflecting most of radar echoes to a single direction, like off up into space or down into the ground, rather than reflecting such echoes in all directions, to minimize the change that an echo might be reflected back to the radar station. I personally did not pursue that idea because I knew the aerodynamics to know that such an aircraft would be extremely unstable, where no human pilot could safely fly it. I did not know that at the same time, Darpa and the Pentagon were designing Stealth aircraft such as the F-22, but they felt they solved the problem of being too unstable for a human pilot to fly it by having a bunch of very advanced computers totally control the actual flight. Very few people are aware that the 'pilots' inside F-22 and other Stealth aircraft do NOT actually do much. They are pretty much still in the aircraft IN CASE the computers would fail, but should that ever happen (in their REALLY redundant computer systems) human pilots could not safe it anyway and it would still crash.
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In both World War I and World War II, similar vulnerability was regularly demonstrated. In World War I, German submarines easily sunk many ships with their torpedoes. In World War II, submarines and their torpedoes again took a heavy toll, but aircraft bombing also was very effective.
Modern warships are built with extremely thick steel hulls, to make them more resistant to such attacks. However, rocket based weapons are MUCH more sophisticated, as well. The example of the single Exocet missile seems clear. That one small missile disabled the ship. What would have happened if 40 such missiles has been launched at that ship? Or at a convoy of ships? Or at a battle fleet? The extremely rapid movement of the rockets and the rather slow movement of the massive ships makes them rather like sitting ducks!
Many modern foreign rocket-based weapons are radar guided. There may be a way to mislead enemy radars as to the existence and location of ships in a fleet. In 1990, I was invited by the Pentagon and our Military to meet with several of their representatives (several Colonels and their Aides) of the US Military and the Government (in Indianapolis) to present and offer this technology. During my presentation, one of the Colonels asked one of his Aides if I might be referring to a super secret Pentagon technology, by a series of numbers and letters and slashes. The Aide responded to the Colonel positively, saying that I was describing something slightly different to what the Pentagon was developing. The Colonel then turned to me and commented that none of the rather slow bombers had ever gotten shot down during the many years of bombing North Viet Nam during that War (some years earlier) and he said that a similar Pewntagon technology had beeen involved, but that he could not tell me more since the technology was still totally seecret.
After my presentation, they indicated that they did not feel that there was any actual need for my technology. They also implied that there was nothing particularly secret about what I proposed, so I figured I'd now create this web-page, several years leter, to present it. I am still convinced that the technology has potential value.
It looks like the Pentagon DID see value in my comments, as in early February 2017, it was announced that a remarkably similar ship, a Destroyer, is now likely to be sent to South Korea, and a variety of videos showed essentially MY 1990 ship!
Some American aircraft apply some aspects of Stealth technology. Very angular shapes is quite important in dealing with specular reflections. Think of seeing a car with a curved chrome bumper on a sunny day. This kind of surface creates almost entirely specular reflection. No matter where you are, you see a tiny but very bright reflection of the sun which gets to you. Now, imagine if that bumper didn't have that continuously curved surface, but rather just flat surfaces with sharp edged corners. Now, nearly anywhere you are, you will not see ANY reflection of the sun off of it! It turns out that the boxy shape tends to make ALL the reflection go to one very specific direction, with almost no specular reflection going anywhere else. You may have noticed some flat truck windshields that almost blind you with the reflection, but only when you are at a very specific position.
As applied to radar, as long as the specular reflection is all reflected in ANY OTHER DIRECTION than back to the originating radar station, no specular echo will ever be received, and so the object will be essentially invisible on radar. I had a big, old, ugly, 1972 Ford Van, that I considered modifying as an experiment around 1984. On the front of it, I considered mounting a giant flat (specularly-reflective) metal mirror, with the lower edge farther forward than the top. So it would have sort of looked like a sloped-back wedge from the front! This would have specularly reflected ALL radar signals upward into space, with NONE ever being reflected back to a radar gun. This would have made the big vehicle effectively invisible on Police Radar! (Essentially, only exposed surfaces such as the tires could still reflect radar signals back to a radar gun, but that reflection would be very minimal, comparable to the radar echo off of a dog-sized object. Most radar guns have a sensitivity adjustment where such weak echoes are ignored.)
Of course, as soon as the mirror got even a little dirty, it would then ALSO create DIFFUSE reflection, which WOULD cause a relatively weak echo to get back to an originating Police Radar, so the premise is impractical there. American stealth aircraft have angular shapes for the exact same reason as described above. They deal with minimizing diffuse reflections by using special coatings (paint) to absorb rather than reflecting those wavelengths. By combining the two types of technologies, those aircraft suppress both specular and diffuse reflection, and therefore accomplish virtual invisibility on enemy radars.
It is briefly necessary now to discuss an entirely different subject. There are some industrial sound-protection safety earmuffs, that are high-tech. Instead of just trying to muffle sounds that approach a person's ears, these products have a microphone to sample the incoming sounds. They then appropriately amplify AND INVERT the signals. It might first seem that the user would then be subjected to TWICE the loudness of the incoming sounds, but that is not true. By precise synchronization of the artificially created inverted signal, the result is that the two loud sound sources cancel each other out, eliminating virtually all of the sound! These hearing-protection devices have become quite common in industry, with current prices of a few hundred dollars.
These products are based on a very well established Physics concept called "destructive interference of waves" Two (traveling) wave patterns which are identical and exactly out of phase with each other will cancel each other out, leaving nothing remaining!
The proposed Ship Stealth invention is based on the same concept. Instead of sound waves, we would be dealing with radar waves, which are equally subject to being cancelled out by the addition of an inverted duplicate signal. The main difference is that sound waves travel relatively slowly (at the speed of sound) while radar waves travel about a million times faster, at the speed of light. Other than that, the situations are quite similar.
The result of this is an almost complete cancellation of the echo from the actual ship structure! The radar installation that sent out the radar beam would NOT receive an echo with which it could become aware of the ship's presence!
If the extended boom antennas (possibly with the electronics immediately there, for faster processing) extended out 20 feet beyond the ship body, then around 20 nanoseconds would occur before the incoming radar signal actually hit the ship body, and another 20 nanoseconds would pass while the radar echo traveled back to where the antenna was. At that time, the artificial (inverted) radar echo should begin to be emitted, to cancel out that echo.
For any real computer, with real circuit wires and antenna, this rapid of a response may not be possible. Signals cannot move in wires any faster than the radar signals and echoes move through the air. The computer processing time would almost certainly make it so that at least the first small part of the radar echo would not be able to be cancelled and so it would actually be reflected back to the radar installation. However, as long as the bulk of the echo was nulled out, the received echo would appear to be the echo from a very small boat, rather than from a large ship.
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C Johnson, Theoretical Physicist, Physics Degree from Univ of Chicago