Donna Wieting, Chief Fax 301-713-0376 Dear Ms. Wieting: In the Spirit of Aloha, these comments on the Navy LFAS project demand the following: 1) The Navys application for a "small take" permit must be summarily rejected as totally absurd. Restore the quiet and sanctity of our planets oceans! Pull the plug on LFAS. Stop the racket! 2) The Navys LFAS FEIS is fatally flawed by its bias, poor science, and its ridiculous extrapolations from limited and absent data that demonstrate our massive ignorance of the many marine species in their environment, and LFASs effects on them. Based on this document alone, the NMFS must reject the Navys application for a "small take" permit and demand a totally new or supplemental EIS. 3) I conclude that the basis of the Navy LFAS FEIS is a "reverse engineering" attempt to justify primarily the 180dB level of sound as "safe" despite much accepted evidence to the contrary. This is the opposite of science. Were the NMFS to grant the Navys request, this criterion would be applied to all future applications, giving the Navy carte blanche to continue in their decimation of the oceans creatures with many other systems that will come up for approval in the future. In this sense, the LFAS project is a "red herring" to distract NMFS and the people of America from the totality of the change in naval warfare now underway. The LFAS is merely the start of a "sea change" in the nature of warfare, a harbinger of even more lethal systems that the Navy will seek to deploy in the future. Close this barn door now while we still have reasonably intact oceans and the Whales, Dolphins and fish are still alive. 4) Applying the "precautionary principle" to the demonstrated and possible harm of the LFAS technology, its testing and deployment must be rejected. The burden of proof is on the Navy to prove that LFAS is safe. This they have utterly failed to do. Therefore, the permit for a "small take" must be rejected until such proof is provided. Given this, NMFS lacks the data to conclude that LFAS will have a "negligible impact" on the planet. Again, on this basis alone, the Navys permit application must be rejected. 5) The existence of significant new data and results especially concerning resonance effects of LFAS on lungs, sinuses, ears, fish bladders, and other structures, has yet to be considered in any meaningful way by the current FEIS, and the implications of the novel forms of damage that this new data suggests that LFAS may cause REQUIRES the NMFS to demand a new or supplemental EIS that takes this data into account. The Navy has the capability and resources to conduct a thorough review and modeling of all this data, including, for example, full finite element analysis models of the response of the ears and air spaces of the Cetacea and other marine mammals to LFAS sounds to access the potential for tissue damage, hearing loss, and death. New empirical experiments must be done to access the implications for the oceans as a whole and the creatures that live in them, and the effects on ecosystem performance, productivity, biodiversity, extinction rates, and numerous other factors. Thus the current permit application must be rejected pending proper analysis and research incorporating this new data showing clearly that LFAS is safe for our planet. 6) New data, yet to be address by the Navy, or NMFS, or the current Marine Mammal Protection act, or the Endangered Species Act have arisen during this comment period. These data demonstrate: a) the self-awareness of the Cetacea, as demonstrated by recent "mirror" experiments. 7) Divers, swimmers and children in the water are at risk from LFAS which may already be having deleterious effects on coastal human communities. The sum total of demonstrated effects and plausibly predicted effects of LFAS exceeds the "small-take" criterion and I therefore completely reject any conclusion of a "negligible effect" by NMFS. Besides the deaths of Cetacea, the effects could include changing the migration routes of birds that depend on sensing low-frequency sound for navigation and disrupt plankton and micro-organisms in the oceans. The damage that may occur can effect our very food supply by killing fish, disrupting ecosystems worldwide, reduce the biodiversity of the oceans and in the process endanger much of the life of the Earth, especially humans that may die when their food supply is reduced. LFAS, should it effect the oxygen production of the oceans, may even damage the air we breathe. We, at this point, must consider this and other effects of any system that will be implaced over 80% of the oceans, and will be deployed by many other nations as well. Should NMFS approve the Navys application, it will thus give tacit approval to other nations efforts along the same lines. 8) The Navy has failed to include all relevent aspects of a total project in their FEIS. This is called segmentation, and is against the law. Therefore, NMFS must reject the Navys appliction until this is corrected. Specifically, the 4 LFAS test ships are only the start of a much larger testing program and deployed systems. The Navy has already cut contracts for 23 more LFAS vessels (Dr. Alex Leonard, personal communication). By limiting the FEIS to just the effects of 4 test ships while fully intending a to use 27 ships or more?? of the same type shows that they are guilty of segmentation to obscure the total effects of LFAS from the NMFS, the American people and Congress. Changes in Undersea Warfare In fact, LFAS is part of a massive change in tactics and strategy which is underway as I write this. Part of this change is the creation of supercavitation (SC) technology, pioneered by the Russians, and presented in the current May 2001 issue of Scientific American. It shows that we now have rocket propelled torpedoes capable of 200 MPH+ speeds. It is rumored that the Kursk was sunk when a Skval (Squall) torpedo malfunctioned. Already the Russians (our NATO allies?) have sold Skvals to China, Iran, and France, at least. They have also been selling Kilo Class diesel-electric submarines to nations like North Korea and China. These subs are super quiet since Toshiba released the means to make quiet propellors several years ago. With the addition of aluminum burning engines, or fuel cells, for example, these subs are much quieter than current nuclear subs and can have ranges like 4000+ miles. The supercavitatiing technology is a means by which an underwater vehicle creates a shock wave at the nose of a vehicle, and then pumps gases from its rocket engines behind the shock wave to create a bubble around the whole vehicle. This reduces drag immensely, and may allow hypersonic speeds underwater. With the addition of stealth technology, this may lead to hypersonic stealth submarines and other similar weapon systems. One of the best ways to propel an underwater SC vehicle or torpedo is a detonation wave rocket engine. These were tested on torpedoes some 30 years ago by Jet Propulsion Laboratories. They had a specific impulse of between 800 and 1000 underwater. Shock Wave Damage? I once was personally involved in the testing of two types of detonation wave engines in the air, and they are very loud. They make a rapid series of explosions that generate a nearly continuous series of shock waves. Since this is a likely method of propulsion for SC technology, I ask the NMFS to look into the possiblility that the LFAS is a cover for such testing, especially in the Bahamas incident. One reason I suspect this is the description of the damage to the whales in the Bahamas includes: Bleeding from the
eyes While Dr. Lee Tepley and I, along with Ken Balcomb, Steven Birch. David Willams, and others have come to the conclusion that LFAS can certainly cause barotrauma through airspace resonances, and consequent ripping of tissues, it is curious that several of the areas of damage in the Bahamas incident, like the eyes and brain, lack air spaces to resonate. So the question arises: What exactly caused the damage to the whales in the Bahamas? According to Dr. Ketten, an expert in Cetacean hearing and hearing damage whose expertise is acknowledged by the Navy, and who is performing the analysis of the damage to the whales that died in the Bahamas -- the kind of damage seen in the Bahama whale deaths are consistent with SHOCK WAVE DAMAGE. There are many possible sources of shock wave damage. The most direct is simply a large bomb explosion in the water. They generate lethal shock waves out to various ranges depending on their size. Yet another cause is that the whales came too close to the sonars being used. At very close ranges, the high intensities of sound could simply rip tussues. Another possibility is that LFAS and the Mid-Range Sonars at close ranges can produce shock waves, especially if used in a Time-Reversed Acoustic mode. Vortex Rings? I feel that similar techniques could develop powerful vortex rings in the water that would travel long distances at high speed. This is something like a smoke-ring under water that could carry large energies to extreme ranges while maintaining its shape and power. Super Cavitatiting Torpedo Tests? Still another likely possibility is that a Super-Cavitating device, perhaps a torpedo, driven by a detonation wave engine, would produce large shock waves both from the bow shock required to make the SC bubble around the torpedo, as well as repeated and rapid shock waves from a detonation wave engine. Any creature near this device as it went by could be severely injured. If the device were traveling at 200+ MPH, there would be little chance for anything to get out of the way. One reason to investigate such a possibility is that ALL the beaked whales in Ken Balcombs study group are now gone, and presumed dead. What mechanism could kill ALL of them? Perhaps an SC torpedo in cruise mode, with navigation aided by external sonars, or wire-guided, traveled a long distance through an underwater canyon and the shock waves propagating from it killed them. Please look into these possibilities. The US is already developing SC bullets for area defense. Thus, undersea warfare is tending toward something similar to rapid dogfight styles. In this environment, it is a serious question what will happen to anything living in the oceans. And this is still just the beginning. There are phased array focusing electromagnetic explosion generators intended to eliminate mines, hypervelocity SC bullets to be fired from helicopters to eliminate mines and other targets, and I am sure, other newer and acoustically loud devices. From a former electronics specialist on nuclear submarines (see Appendix II.), I have learned that LFAS is likely to be used for detection. While I have commented earlier on the Time Reversed Acoustics mode that LFAS could be operated in, and that this made it a weapon, it appears that this would be only useful at relatively short ranges. I still maintain that the Navy is only giving us partial information on LFAS use and capabilities. This is inherent in its nature, since the Navy is hiding behind classification. Therefore, some of the following must remain speculative until such data are released. The Russian fleet has stayed in port for some 2 years. So their threat to the US is greatly reduced. The Russians are, however, selling Kilo Class diesel-electric submarines to various nations, notably North Korea and China. As noted above, they have sold SC torpedoes to other countries and continue to develop the technology, perhaps to include a SC Submarine capable of hypersonic speeds. The US has similar research programs underway. The main point here is that such SC technology changes the entire complexion of undersea warfare to one in which it may be dangerous just to be in the water. The military is therefore one of the largest threats to the oceans and its creatures. If NMFS chooses to exercise its legal mandate to protect marine mammals and by extension, the oceans, then they will begin investigations that will curtail military environmental degradation. Remember, most the devices being developed will be tested eventually, and then made operational, then deployed, by the US and other nations. The total effect on the oceans will be vast, and therfore, it is time to look at this problem and stop these develpments. I suggest that NMFS contact Congress and the UN on these matters. The operation of the US Navy and other navies is an ongoing and increasing source of damage to the marine mammals and the oceans. If this continues there is a possibility that when the oceans are safe for democracy and after years of operating the LFAS, other sonars, SC torpedoes, SC submarines, phased array explosion devices, SC bullets, etc. etc., the oceans will be clean of spurious targets like fish, whales, dolphins, seals, manatees, dugongs, human swimmers and most everything else. There is the dubious prospect of the military killing the planet they seek to defend, even though they may never fight a war. Then, if a full undersea war does occur, there will be even more chaos and destruction. It looks as though even peacetime operations could kill the oceans. As Eisenhower pointed out, we are being crucified on a cross of iron, run by the military-industrial complex. The NMFS can help divert this outcome by calling on Congress for full hearings on the funding, testing, and environmental damage now occuring from the actions of all the militaries of the planet. 9) The range of the requested Navy permit exceeds the authority of the NMFS and involves the resources and territories of many countries, and beings which are the common living cultural heritage of all the peoples of the world. Any permit covering 80% of the oceans is by definition, beyond a small take exemption, and by definition beyond the description of negligible impact. We demand that you rule against the Navys request, and admit that this matter is well beyond your jusidiction. You must refer this matter to Congress, the President, and on behalf of the Cetacea Nation, to the State Department and the United Nations. This matter is one which is properly dealt with by agreement with all the nations and peoples of the Earth, especially our beloved Cetacea people. 10) How can NMFS possibly justify its apparently cozy relationship with the Navy? Why have you gone along so thoroughly with the Navys wishes? The Navy is the agency you are legally mandated to REGULATE, and such regulation is MANDATED by the Marine Mammal Protection Act. Some 80-95% of Americans, and a similar percentage of all people support the preservation and protection of the Cetacea and wish an end to whaling, pollution and military activities that may harm them. You are betraying your sacred public trust should you give in to the Navys request. Deny this Navy Permit and all similar permit requests in the future. Please do your job. 11) Mechanisms by which LFAS and Mid-Range Sonars may damage Cetacea and other creatures. As detailed by Dr. Ken Balcomb, and Dr. Steven Birch, the LFAS sonar may cause resonances in air spaces at various depths. The Cetacea have extensive air-filled sinuses that are used to compensate for depth changes and to reflect sounds as part of their sonar systems. At certain depths and frequencies, the air spaces will resonate. At resonance, the air in the cavity rapidly changes size, getting bigger and smaller, and if the change is large enough, it can rip tissues, causing bleeding. The middle ear has an air cavity that must change in size with depth. Other sinuses and the lungs can also resonate and be damaged. With Dr. Lee Tepley, I have calculated the resonant frequencies at various depths for male and female free divers, scuba divers, as well as the Cuvier Beaked Whale lungs and pterygoid sinus, the lung resonance of the Bottlenosed Dolphin, and the Finback Whale lung. This is detailed in the tables following this paper. Tables of Resonance and Displacement can be found HERE In addition, the whale ears use a tympanic bone in place of our eardrum to gain low frequency response. The tympanic bone in the dolphin resonates at a few hundred Hertz according to Dr. Gerald Fleischer, author of Evolutionary Principles of the Mammalian Middle Ear, Springer-Verlag, New York, 1978. He has determined that the baleen whales also use the tympanic bone for detecting low frequency sounds, much like the toothed whales. He states that: As to your questions I can tell you : Thus we see that the Navy could have easily contacted Dr. Fleischer, whose work is well known to Dr. Ketten, for example, and determined exactly what the resonance effects for LFAS are. From the Scientific American article on SuperCavitation, we learn that the Navy used 76 Cray computers to calculate the turbulent flow around torpedoes, using finite element models. Something similar could solve all the remaining questions of airspace and lung resonances for the Cetacea and other creatures. Surely that was something the Navy should have done. After all, they say they spent 10 million dollars on their study. One wonders what the spent the money on, since so little progress is reflected in their FEIS. This leaves Dr. Tepley and I and people like us to do the Navy's job for free, on our own time and resources, that are much smaller than the Navy's. One also wonders at the near total silence of the marine mammal science community on this issue. I suspect this is because the Navy funds a majority of the work in this field and that scientists know that they have to "tow the line" or lose their grants and positions. That said, Dr. Tepley and I got some useful results. I encourage you to look at the tables. I will summarize the results here. A) There is little to distinguish LFAS from Mid-Range Sonars. 12) Co-Resonances In Appendix IV. is shown the resonance model for the middle ear of the dolphin. (after Fleischer) The resonance for reasonable values of the radius of the box, the plate area and thickness representing the tympanic bone of the dolphin and other parameters are estimated and come out in the LFAS range. As pointed out by Dr. Lee Tepley, whales and dolphins might be hit by several resonances in one dive. We would like to have had the time to see if there are co-resonances, in which, for example, a lung at resonance becomes a sound source of its own. If the Q of the system is 10, then the acoustic re-radiation of the lung is actually 10X the incoming sound pressure that sent it into resonance. Therefore, the lung at resonance becomes an acoustic amplifier. Then, in calculating the effects of LFAS, one must consider any resonant cavity to be a sound source LOUDER than the original LFAS signal, just multiply by Q. 13) Types of Marine Mammal Ears There are at least 5 basic types of ears involved in the LFAS affected species: a) a typical mammal ear as in seals, For the Navy to ignore these differences, and lump all whales in the same category, as if they were similar in most regards is reprehensible. To then generalize as they have to all species and all oceans and all conditions from so little data is just plain WRONG. ANY conclusion derived by such simplistic analysis must be rejected. If a couple folks with a Pentium 90 can come up with a more valid analysis than the Navy in less than a month of work, with all the problems of trying to work through the misleading arguments of the Navy, with very little resources, one must question what the Navy did with their 10 million dollars that they claim to have spent on their "research". For example, they could have just called Dr. Fleischer, whose work is known by Dr. Ketten. It seems they spent the 10 million to cover up the truth. Another reason to reject their permit! Finally, Dr. Ketten in her work honestly points out the vast areas of ignorance on which the assessments of LFAS effects must be based, and we should therefore lean in the direction of caution. Dr. Ketten shows that mammal ears, at least in terms of damage, respond rather similarly to similar sound levels. Hearing damage begins at about 80dB and goes up from there. There is absolutely zero reason to think that 180dB levels are safe for anything! Therefore, reject this self-serving conclusion of the Navy. After all, we are talking about the health of children, woment, men, dolphins, whales, seals, manatees, dugongs, fish, and all the other inhabitants of the ocean. If I were placing a bet, it would be a good bet that the Navy is wrong. In the interest of all of us that live in and play in and work in the oceans, NMFS must reject the LFAS project as presented, and DEMAND of the Navy, a NEW and HONEST EIS. I could go on. As must be abundantly clear, the Navy is whitewashing the truth, pulling the wool over our eyes. Please see through their illusions to the truth. Thank you for your patience! Please decide for the people, Please decide for the Cetacea. The fate of our oceans may be in your hands. Choose wisely and well! Please follow your heart and 90% of the American people and reject the Navy's permit. Sincerely, in the Spirit of Aloha,
CC: President George W.
Bush
APPENDIX I. HILO RESOLUTION
As an example of the type of legislation beginning to be enacted with regard to the Cetacea Nation, we offer our "Hilo Resolution"
WHEREAS, the County of Hawaii's coastal waters are biologically unique and a number of endangered or threatened species either live in the coastal area or depend on coastal waters for survival; and WHEREAS the County of Hawaii is a unique and still pristine environment, the natural areas and species here are precious and WHEREAS this region is home to many whales, dolphins, Monk seals and other marine species and WHEREAS Humpback whales and others come here regularly to feed, rest, birth their children, which is a rare and wonderful event happening in only a few areas of the entire planet, and WHEREAS, abusive exploitation of dolphins and whales for research and military purposes has been authorized by federal law and regulations of the defense and commerce departments including Title 10 U.S. Code 645 section 7524, that such abuse is abhorrent, and that secrecy in marine mammal programs of the government is distorting both science and democracy; and WHEREAS, the County of Hawaii supports higher water quality standards to eliminate pathogens (viruses and bacteria) and nitrates and sulfates from sewage and toxic chemical pollutants from industry which create conditions hazardous to all species in our coastal waters, WHEREAS there is now a clear opportunity to open full communication with the Cetaceans (whales and dolphins) and initiate other worthy projects to integrate Cetacean and human culture and WHEREAS scientific reports and experience show that the Cetacea are able to restore the wholeness, sanity and joy of humans, have assisted in the birth and restoration of children, and have been a delight to humanity across many ages and cultures, and WHEREAS the growing interest in Cetaceans has led to whale watching and other enterprises are already generating at least $350,000,000/year to the global economy, and is a major economic input to our economy and WHEREAS, dolphins and whales have brains in the human range of size or larger, County of Hawaii recognizes that the Cetacea are the first global society, antedating humans, and have lived in harmony with the ocean for millions of years and WHEREAS, the County of Hawaii opposes pollution or disruption of the ocean environment or the communicational sphere or society of the Cetaceans, and opposes the theft of their acoustic bandwidth for commercial, military or research use; and instead supports cleanliness and maintenance of the oceanic environment and availability of the acoustical ranges they require and WHEREAS, the County of Hawaii recognizes dolphins and whales as a LIVING CULTURAL RESOURCE that benefits the peace, beauty and environmental health enjoyed by humans, and holds that their best, highest role is as a living cultural resource to be seen, listened to, communicated with and studied respectfully and harmoniously for what knowledge or wisdom they may impart; and WHEREAS, County of Hawaii acknowledges surveys estimating that 95% of the American people support this view and advocate legal protection of dolphins and whales as individuals; and WHEREAS dolphin researcher Dr. John Lilly and others have proposed that the United Nations at last recognize the Cetaceans as aware, intelligent, sentient beings entitled to our global protection and respect and who are entitled to the same rights and privileges as are human beings, and WHEREAS the City of Malibu California has already declared its coastline a "shared human/Cetacean habitat" where the rights of the Cetaceans and the humans to a clean environment and proper treatment are already established, and WHEREAS the Hawaii area is ideal for the development of these and similar projects that will bring global interest to Hawai'i, and WHEREAS Hawaii is inhabited by Earth-loving people who support and honor all creatures, and WHEREAS the County of Hawaii can be a model for planet friendly communities everywhere, where people, Cetaceans, the Earth and nature are all honored, THEREFORE we declare that the County of Hawaii and its coastlines is a now officially recognized as a Human/Cetacean Community, a community shared between the Cetacea and Humans and THAT the County of Hawaii is a sanctuary for the Cetacean cultures and the humans that choose to interact with them, and NOW, THEREFORE, BE IT RESOLVED that the Mayor and County of Hawaii, do hereby declare Hawaii a "Human-Cetacea Shared Environment" and resolve to consider the wellbeing of the local resident and migrant marine mammals and encourage continuing efforts in cooperation with governmental and civic organizations to improve the relationship between human beings and Cetaceans. THAT the Cetacean and Human rights to a clean and protected environment shall be upheld and THAT existing laws shall be administered in ways consistent with this resolution, that existing laws protecting our coasts, cultures, creatures and plants be properly administered, and that other legislation required to support the above goals be enacted. WITH THIS RESOLUTION the County of Hawaii will protect, restore, preserve and enhance the enviroment we mutually share with the Cetacea.
Appendix II. The State of Naval Warfare & the Threat Environment
From a former Naval Officer serving on nuclear submarines I corresponded with: Q: Do you think that the LFAS could disrupt the 200 mph plus torpedoes? A: Good question: I don't know. I suspect, however, that its real value lies in its being able to penetrate thermoclines. It's a standard sub offensive tactic to lie in wait at low power levels below a thermocline (because of the change in water density, a thermocline tends to reflect current sonar upward). LFAS, because of its longer wavelength, may provide greater penetration at the boundary layer (as well as increased detection ranges). With several highly sensitive, passive receivers in the water (well removed from the transmitter), much fainter returns can be heard and trianglulated. I suspect that increased detection range accounts for the high power levels. Q: As Capt. Williams suggests, the LFAS might strip the enclosing bubble from the projectiles and slow them or destroy them. A: It certainly seems possible (and I don't know enough about either high speed torpedo technology or LFAS to provide much more than SWAG comments), but, it would seem to me that such "stripping" would require very high power levels (at any frequency). Since signal strength decreases rapidly with distance from the transmitter, such an effect would only be relatively short-ranged. With that in mind, the target still has a problem with a conventional torpedo speeds (unless the sonar signal itself can damage/destroy the torpedo or cause the rapid increase in friction to do the same thing). Current ASW strategy focuses on long range detection and prosecution of unknown sub contacts before they are within weapons (either missle or torpedo) range. This accounts for the composition and battle formation of a typical carrier battlegroup (CVBG). I'll forego a discussion of CVBG ASW tactics here. Suffice it to say, if a torpedo is detected in the water, ASW efforts are consided a failure. One other note here; launching a weapon from a sub immediately broadcasts your position. And a torpedo track (or missle for that matter) points right back to the launch position. Q: In any case, I now have a greater appreciation of what the Navy feels they have to deal with. A: It's a tough nut to crack, no doubt about it. One interesting point ... above the waterline the sky is transparent for about a 200-300 nm radius because of the use of aircraft early warning radar (AEW). Yes, control of the air requires advanced aircraft (when defending the fleet, fighters are defensive weapons), F/A-18s and F-14s and fairly sophisticated missles. However, it's AEW that makes them so effective -- the incoming threat can be assessed and fighters assigned well outside the enemy aircraft's engagement range. Had an interesting conversation with an active duty submariner recently. Among other things, two topics might interest you. First, he described the current state of the opposition to USN operations, worldwide. The Russians have not sailed in two years, according to this gentleman (and several other sources as well). Russian nukes are tied to their piers providing electrical power to shore. North Korea has a sizable number of mini-subs. The Chinese are operating a fleet of fairly modern desiel-electrics (Kilos and Type 209s I believe). In the Gulf States/Middle East the are a handful of older desiel-electrics. His overall assessment was "all coastal defense stuff" and it was his belief that there was no blue-water challenge to USN operations. I did not get a sense from him that any of the above were considered significant threats. He also described a fast attack boat that had recently been fitted with a new sonar which had exceeded its development cost by a significant margin and was now consuming the boat's operation maintenance budget. Said the problems were such that the boat could no longer purchase replacement parts for the powerplant... Have been doing a little bit of basic research on LFA and noticed a few things: According to the Sea Shepard statement to NMFS opposing deployment of the LFA sonar: "The Navy has asserted that the LFAS testing program was not designed to evaluate "worst-case scenarios" and thereby justifies its extrapolation from harassment effects at RL 140 db to effects at RL 180 db. However, the Navy's definition of "employment" of the system does not include the actual use of the system for the purpose for which it was created. Outside of war games, at any time of declared "heightened threat conditions" the Navy will claim exemption from environmental laws for reasons of national security and all proposed mitigations will be abandoned, meaning LFAS is likely to be operated in near-shore areas, at full 230 db source levels, and whether or not cetaceans are sighted within 1 km of the deployment vessel. As the Navy intends to exempt itself from NEPA whenever it deems it necessary -- inevitably creating thereby the "worst-case scenario" for which they admit they have not conducted tests..." From the information that you forwarded from Dr. Steven Birch: "...optimum frequencies for detection decrease as range increases..." And from sjforsbe@bayou.uh.edu writing on the sci.military.naval newsgroup: "The materails <sp> are more commonly notated as "PMN" (for lead,magnesium,niobate). A search for 'PMN' and 'sonar' or 'transducer' should bring up many hits." "Basically PMN is used to form an electrostrictive ceramic. The primary use of such a material is in high power low frequency application, like Airborne Low Frequency and Low Frequency Active, to name a few Navy projects. PMN materials have been under investigation/development for years now. They are useful in producing powerful low frequency signals, but amont <sp> their drawbacks, AFAIK, is the fact that they are relatively tough to manufacture and have some operational temperature sensitivities as well". "I think "perfectly transparent" is a bit of an exaggeration, but there is no doubt that the USN has been throwing a lot of money at technologies underlying low frequency work for sea sensors. Of course, developing transducers that allow for even greater power density begs the question of possible environmental impact - but that is another subject." All the above, when combined with Steven Ashley's Scientific American article, my naval contacts, current naval ASW tactical doctrine, the nuclear weapons capability of the PRC and the political situation regarding PRC/ROC/USA, point to a perceived significant threat from PRC Kilos and 209s to US Navy CVBGs. Since the CVBG is the preeminent power projection mechanism for US foreign policy, according to strategic doctrine any threat to the CVBG represents a threat to America's dominant position in world affairs and must, therefore, be countered immediately and at any cost. With all the assertations in publications such as Foreign Affairs that the PRC is emerging as both an economic and military threat to American interests, it's not surprising that LFA is being rushed into deployment and its harmful environmental effects downplayed. It remains my contention that, at present, LFA is a long-range ASW detection system (capable of penetrating thermoclines). However, with 230db of power on tap, and given the mechanics of supercavitation I can see the potential for its use as a defensive weapon. From my own perspective, were I the CVBG commander, I would much rather use LFA SURTASS as a long-range detection device and then prosecute any unknown sub contacts well outside their potential weapons range. None of this fairs well for our friends in the water however. Any device capable of inducing a sonar signal into the water at 230db, whether for detection or active defense, is going to injure and kill marine mammals on a wholesale basis... [Emphasis Added]
Appendix III. The Resonance of The Human Lung
Developments in the low-frequency active sonar systems used by the world's navies and by oceanographers have led to concern over the unknown health threats posed by underwater sound to divers who are exposed to these systems. Since sound underwater is perceived very differently from the way it is in air, simple extrapolation of noise exposure standards for airborne sound are clearly inappropriate to this problem. The response of the human body to underwater sound is dictated by different physical principles than airborne sound exposures. The lungs are, probably, the most dramatic example of this. Like all body tissues, they are stiffer in compression and considerably denser than air. Yet, they are much softer and lighter than water. Other body tissue is roughly comparable to water or, like bone, is both denser and stiffer. Normally pressurized by the atmosphere, lungs may have an internal pressure equivalent to 5 or more atmospheres when a person is diving. These facts would lead a scientist familiar with the behavior of bubbles to predict a depth-dependent resonance caused by the motion of the lung against the mass of the surrounding water. If this vibration were undamped by body tissue, the motion of the lung might be amplified by as much as 100 times because of the resonance effect. What was not known until now was: does the human lung actually behave as if it were a bubble? In order to answer this question, researchers from Georgia Tech and the Naval Medical Research Laboratory conducted an experiment in which volunteer navy divers were exposed to underwater sound in an 1100 gallon pool inside a large hyperbaric chamber which is normally used to treat decompression sickness. Varying the pressure within the chamber mimicked the effect of diving deeply without most of the associated risks. At each of 4 depths the motion of the divers' lungs were measured simultaneously using 3 different techniques during a sound exposure. To insure diver safety very low sound levels were used in the this experiment. These produced motions of a few millionths of an inch. The results of the experiment reinforced the hypothesis that the lungs behave much like an air bubble. The measured lung resonances occurred around 39 Hertz (cycles per second) unpressurized and nearly doubled at a pressure equivalent to a depth of 120 feet of water. This was consistent with a lung whose stiffness was dominated by the air within. Due to damping from body tissue, the amplification of lung motion produced by the resonance was factor of 5 to 7. For those who have not experienced the Taos hum and do not recall (or choose to forget) Sensurround from the 1970s, 39 Hz is best described as the sound of a large diesel engine heard from a distance. There are two ways in which the resonant amplification of lung motion could be dangerous to divers. Large motion might damage the lung itself or the lung might act as a secondary source of sound and cause damage to another organ system like the ear. The effects of resonant motion need not, however, be entirely negative. A project is currently underway in which researchers from Georgia Tech and Emory University are investigating the potentially therapeutic effects of low frequency underwater sound. Oscillating chest
compression is a common method for assisting cystic fibrosis
patients in clearing excess mucus from their lungs.
Accomplishing this compression with underwater sound offers
many advantages over conventional techniques such as
pounding the chest wall. The number of oscillation cycles
which can be applied in a session is high (thousands per
minute), the motion produced in the lung is nearly uniform
(this suggests that beneficial effects will be provided to
the entire lung rather than a small region of application) ,
and large motions can be produced without injuring the
patient. By exploiting the lung's natural underwater
resonance, the benefits of this therapy can be achieved with
substantially less input of energy. This has the dual
advantage of allowing the system to be more compact and
providing an additional margin of safety for the
patients.
APPENDIX IV Plate and Box Middle Ear Model ![]() The middle ear of the Ondontocetes such as the Dolphin and Myticetes is represented at a box of radius R, with a tympanic bone plate of area A and thickness t. (After Fleischer (a) and Fleischer(b)) According to the formulas above, the resonance varies with depth as shown in the table. Using reasonable estimates of tympanic area and thickness for the Bottlenosed Dolphin there are resonances in the LFAS range for depths to 287 feet. (Youngs modulus = 1x10^11); Fr = Frequency at resonance; N = number of atmospheres pressure; V = volume at surface and at the resonant depth. Changing depth of "Middle Ear" Fr t (cm)
A plate
(cm^2) R Box
(cm) N Depth
(ft) V @
Surface V @
Depth 209.36 0.02 3.92 2 1 31.98 33.51 33.51 307.77 0.02 3.92 2 2 63.96 33.51 16.76 400.67 0.02 3.92 2 3 95.94 33.51 11.17 498.77 0.02 3.92 2 4 127.92 33.51 8.38 605.31
0.02 3.92 2 5 159.9 33.51 6.70 721.07 0.02 3.92 2 6 191.88 33.51 5.59 845.90 0.02 3.92 2 7 223.86 33.51 4.79 979.26 0.02 3.92 2 8 255.84 33.51 4.19 1,120.5 0.02 3.92 2 9 287.82 33.51 3.72 1,269.0 0.02 3.92 2 10 319.8 33.51 3.35 Tables of Resonance and Displacement can be found at: |
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