This Sounds So Cool ( See what I did there? )

There are so many applications of Acoustics in every day life.  In fact, scientists are coming up with new applications every day.  Many people think of the most popular applications of Acoustics like Ranging and Imaging.  If you think the only applications of Acoustics are Sonar and Ultra Sound Imaging, you would be so wrong. […]

There are so many applications of Acoustics in every day life.  In fact, scientists are coming up with new applications every day.  Many people think of the most popular applications of Acoustics like Ranging and Imaging.  If you think the only applications of Acoustics are Sonar and Ultra Sound Imaging, you would be so wrong.

For example, China has discovered that they can use Acoustics to help them deal with the effects of Global Warming.  In order to increase their water supply during drought periods, China has discovered that by aiming low frequency sound waves at clouds, they can stimulate that cloud into dropping rainfall when it otherwise would not have done so.

As another example, China has also discovered a more efficient way to limit the number of plastic fibers that get come out of washing machines and get released into the drain.  This was required because conventional filters on washing machines do not catch the tiny fibers that can be so destructive to the marine ecosystem.  By using Acoustic filters that produce a type of forcefield in the water, all the fibers can be collected.

Going forward, finding new and important applications for Acoustics is ripe for technical innovation.

To learn more about applications of Acoustics, consider taking the upcoming ATI course  Acoustic Fundamentals, Measurements, and Applications.

This four-day course is intended for engineers and other technical personnel and managers who have a work-related need to understand basic acoustics concepts and how to measure and analyze sound. This is an introductory course and participants need not have any prior knowledge of sound or vibration. Each topic is illustrated by relevant applications, in-class demonstrations, and worked-out numerical examples. The instructor for this course reaches out to all registered students prior to the class to learn about their interests so he can tailor the course to meet their needs.  The upcoming offering of this course is Guaranteed-To-Run.

You can learn more about this course, and register to attend at

Acoustics Fundamentals, Measurements, and Applications – ATI Courses

And, as always, you can learn about the full set of courses offered by ATI at www.aticourses.com

What The Heck Is TMA?

Sonar and Target Motion Analysis Fundamentals is a course being offered by ATI starting on October 19.  Typically, the purpose of this blog is to share the real-world relevance of the material being taught in the class, and typically, there is a lot of real-world relevance to talk about.  Unfortunately, in this case, there is […]

Sonar and Target Motion Analysis Fundamentals is a course being offered by ATI starting on October 19. 

Typically, the purpose of this blog is to share the real-world relevance of the material being taught in the class, and typically, there is a lot of real-world relevance to talk about.  Unfortunately, in this case, there is not much real-world relevance to discuss. 

So, if you are a submarine sonarman, or if you are an engineer developing tools for use by submarine sonarmen, then this is the course for you!  You surely already understand the meaning and importance of Target Motion Analysis, and this class will offer insights that you may not have been exposed to in your Navy or workplace training.

For the rest of the world, since I can’t offer any real-world relevance, I will at least explain what Target Motion Analysis is, and why it is so critical to sonarmen.

Surface Ships use Radar in much the same way that Submarines use Sonar.  One major difference between Surface Ships and Submarines is that stealth is critical to the submarine, and less important to the surface ship.  So, submarines typically do not want to emit any energy from their ship, as that would be detectable by the adversary.  As a result, while Surface Ship Radar actively emits energy, submarine sonar does not.  Submarine Sonars act passively; it only listens to naturally occurring noise, it does not transmit any energy.

When a Surface Ship Radar emits a pulse and listens for a return, the radarman is able to pinpoint the precise location of the contact.  Over time, he can examine the track of his contact, and use this information for tactical purposes.  The process is fairly simple compared to what happens on a submarine.

When a submarine sonarman hears a contact using his passive sonar, he knows nothing more than the direction it is coming from.  Over time, he can develop a time history of the direction to the contact, but that is not the same as a Target Track.  The time history of target direction is of little use for tactical planners; they need to know the track of the contact, which includes the contacts range and direction of travel.  In order to convert the time history of target direction into a usable contact track, the sonarman, or the sonarman’s computer programs, must execute “Target Motion Analysis”.

If you find this explanation interesting, or if it sounds like something that you may be able to apply to your work, please consider joining us for this class.  You can learn more about the class, and register for it here.

A complete listing of our upcoming classes can be found here.

Lastly, a complete listing of all of the courses that ATI can offer upon request can be found here.

Yeah, But What If?

Submarine accidents which result in the submarine careening to the sea bottom are spectacular in Hollywood movies and video games, but they do not happen often in real life.  In fact, for the U.S., we have not lost a submarine to the depths since 1968 when USS Scorpion was lost with 99 souls due ( […]

Submarine accidents which result in the submarine careening to the sea bottom are spectacular in Hollywood movies and video games, but they do not happen often in real life.  In fact, for the U.S., we have not lost a submarine to the depths since 1968 when USS Scorpion was lost with 99 souls due ( most likely) to an inadvertent activation of a battery or a torpedo.  Prior to that, in 1963, USS Thresher was lost with 129 souls due to ( most likely ) a piping failure during a deep dive.  Due to actions taken as a result of lessons learned from those two mishaps, the U.S. has not had a major submarine loss since then.  The safety record for U.S. Submarines since 1968 has been remarkable, and the envy of other countries.

Yeah, but what if?

To be prudent, the U.S. must assume that there will be submarine accidents in the future, even if they are not U.S. submarines.  For this reason, the U.S. continues to maintain a force dedicated to the rescue of downed submarines.  Undersea Rescue Command (URC) is the U.S. Navy’s official command for the rescue of sailors during a submarine casualty anywhere in the world.   If you would like to learn more about this command, you can read about it here.

The blog author has had some personal experience working with the Undersea Rescue Command, and all comments that follow are the authors personal opinions, and not an official opinion of the U.S. Navy or Applied Technology Institute.  In case you missed that, please go back and read it again.

Two significant issues that confront the Undersea Rescue Command are funding and localization. 

The funding issue arises from the fact that our submarines are so safe, and our safety record is so good, there is a hesitance to pay too much attention ( and funding ) to an organization which may not ever be called into service.  Unfortunately, there is not much the technical community can do about that; it will have to fall upon the Public Relations Office at U.S. Navy. 

Localization, however, is a problem which the technical community can help solve.  When a submarine goes to the bottom, the Undersea Rescue Command jumps into action, and reports to the vicinity of the accident very quickly.  Unfortunately, the Undersea Rescue Command cannot start their rescue mission until the precise location of the sunken submarine is known, and that is often a difficult problem.  Until the submarine is located, the rescue can not actually begin.  Often, in exercises, or in other countries, by the time the submarine is located, it has become a recovery mission rather than a rescue mission. 

So, how can we simplify the task of locating a downed submarine?  Some of the answer lies in the concept of operations, or things that a distressed submarine can do to facilitate the search for them.  Some of the answer lies in advances in sonars and sonar signal processing.  And the rest of the answer lies in innovative new ideas, for example, using AUVs or UUVs to find distressed submarines ( cool idea ). 

Applied Technology Institute is offering several courses in the coming months that will help you brush up on your skills, so that you can apply them to this problem.  You can find information about our Sonar Signal Processing course, and register for the course here.  Additionally, you can find information about our Passive and Active Acoustics Fundamentals course, and register for the course here.  Lastly, a full listing of ATI’s Acoustics and Sonar Engineering Courses ( including AUV and UUV courses ) can be found here.  If you are interested in a course which is not currently on the schedule, please let us know, so we can try to schedule an offering soon.

As I said earlier, the author has had the pleasure of working with the Undersea Rescue Command several years ago, and was very impressed with the hard work and dedication exhibited by all members of their team.  The following picture shows me and the rest of the JHU/APL Team that worked with the URC.  We are posing inside of the Pressurized Rescue Module which travels to the distressed submarine to perform the rescue.  Although no one would ever want to experience being on a submarine in distress, they should feel encouraged that a team as dedicated and qualified as URC is on the job.

You’re Going To The Moon, Alice

Mankind has always been fascinated with exploring the Moon, and that will probably always be the case.  At first, in the time leading up to the famous first moon landing in 1969, the goal was simply to reach the moon, and spend a short time looking around, and return to earth safely.  Now, 50 years […]

Mankind has always been fascinated with exploring the Moon, and that will probably always be the case.  At first, in the time leading up to the famous first moon landing in 1969, the goal was simply to reach the moon, and spend a short time looking around, and return to earth safely.  Now, 50 years later, the goal is more ambitious since technology can support so much more.  The first objective today is to reach the moon, and stay there.  The next goal would be to use the moon as a landing pad to support exploration of things beyond the moon, most notably Mars.  The NASA Artemis Missions will be the way these objectives are accomplished.  I am not sure about you, but this mission snuck up on me, and I am learning about it now. 

The Artemis Mission is comprised of six projects which together will allow NASA to accomplish its goals of reaching the moon, staying on the moon for long term exploration, and getting closer to ultimate goal of being able to send men (and women) beyond the moon.  The six projects include:

Ground Systems – Upgrading Earth ground systems to support the larger rockets which will be needed

Space Launch System – The new and more powerful rocket that will launch man toward the moon and beyond

Orion – The spacecraft that will bring astronauts to the moon’s orbit, and return them to earth from the moon’s orbit

Gateway – The outpost spacecraft which will orbit the moon and be living quarters for the astronauts when they are not on the moon surface

Lunar Landers – The spacecraft which will transfer astronauts between the Gateway and the moon Surface, and

Space Suits – The new and improved suits that the astronauts will need to carry out their mission.

The timeline for this mission has three major milestones, namely, the three Artemis missions, Artemis I, Artemis II, and Artemis III.

Artemis I – an unmanned flight to test the Space Launch System and Orion, scheduled for 2021

Artemis II – a manned flight to test the Space Launch System and Orion, scheduled for 2022

Artemis III – A manned flight to the moon that will return man to the moon.

This is a truly ambitious mission, and an even more ambitious schedule.

ATI offers a plethora of courses which relate to Space exploration.  Check out our list of Space related courses here.    If you are interested in the legal aspects of Space exploration, you can register for our upcoming Astropolitics class here

Although the author thinks Space Exploration is exciting and important, and I fully endorse all of the goals of the Artemis Mission, I can’t help but wonder why the Government is not spending at least as much money on exploration of the deep oceans.  I would challenge the US to start investing more money in Ocean Exploration, but not at the expense of Space Exploration.  Both of these are important.  I am curious what readers think about this issue, please leave your comments below.

And, if you are interested in Ocean Exploration, ATI has a few courses which may be of interest to you too.  Please check out our full list of offerings here.

And if you simply want to learn more about the Artemis Mission, you can go to the NASA Artemis site that describes the mission in more detail. 

Large Displacement Unmanned Undersea Vehicle (LDUUV)- Experts To Report On October 16, 2013

The rise of Unmanned Aerial Vehicles (UAVs) is driving the development on unmanned technologies in other areas.  Unmanned aerial vehicles (UAVs) are becoming so commonplace that the FAA is hard-pressed to come up with regulations to control their operations. Unmanned marine vehicles, meanwhile, are becoming a hot technology topic, as military researchers push a program […]
The rise of Unmanned Aerial Vehicles (UAVs) is driving the development on unmanned technologies in other areas.  Unmanned aerial vehicles (UAVs) are becoming so commonplace that the FAA is hard-pressed to come up with regulations to control their operations. Unmanned marine vehicles, meanwhile, are becoming a hot technology topic, as military researchers push a program forward to develop a long-endurance unmanned underwater submarine. The experts are scheduled to report on this project on October 16 at Alion Science and Technology Inc. On the schedule of the briefings: LDUUV vision and missions program schedule budget technology risks and payoff technology development and transfer employment operations testing requirements Q & A session You can register by emailing Navy’s Ron Merlene at ronald.merlene@navy.mil Read more here.


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Was A Killer Whale Killed By NAVY Exercises?

Applied Technology Institute offers a short technical course, Underwater Acoustics For Biologists and Conservation Managers, on April 17-19, 2012 in Washington, DC area.  We thought the news below would be of interest to our readers. It appears that yet another magnificent creature of the deep,  a member of the endangered southern resident killer whales, was […]
Applied Technology Institute offers a short technical course, Underwater Acoustics For Biologists and Conservation Managers, on April 17-19, 2012 in Washington, DC area.  We thought the news below would be of interest to our readers. It appears that yet another magnificent creature of the deep,  a member of the endangered southern resident killer whales, was killed by NAVY exercises. The body of the three-year-old female whale,L112, known both as Sooke and Little Victoria, washed up on a beach near Long Beach, Washington, shortly after the Canadian navy was using sonar in Juan de Fuca Strait. According to witnesses, sonar pings, which were recorded by a series of hydrophones, were preceded by an explosion. The necropsy conducted by the experts shows that the whale died from “significant trauma”. This caused an outrage in environmental community, including David Suzuki Foundation, Georgia Strait Alliance, Greenpeace, Living Oceans, Raincoast Conservation Foundation, Sierra Club B.C., Western Canada Wilderness Committee and the World Wildlife Fund. Under Canada’s Species At Risk Act the killer whales are listed as endangered spices. All of the above mentioned organizations call for ending of the military exercises in the a release of all information about activities in the area that might have contributed to Sooke’s death. What is you opinion on this matter? Please comment below.
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ATI Features World Class Instructors for Our Short Courses

Washington, DC Tuesday, November 30, 2010 “Even I Could Learn a Thing or Two from ATI” Video Clip: Click to Watch Since 1984 ATI has provided leading-edge public courses and onsite technical training The short technical courses from the Applied Technology Institute (ATI) are designed to help you keep your professional knowledge up-to-date. Our courses provide […]
Washington, DC
Tuesday, November 30, 2010
“Even I Could Learn a Thing or Two from ATI”
“Even I Could Learn a Thing or Two from ATI”
Video Clip: Click to Watch
Since 1984 ATI has provided leading-edge public courses and onsite technical training
The short technical courses from the Applied Technology Institute (ATI) are designed to help you keep your professional knowledge up-to-date. Our courses provide a practical overview of space and defense technologies which provide a strong foundation for understanding the issues that must be confronted in the use, regulation and development such complex systems. The classes are designed for individuals involved in planning, designing, building, launching, and operating space and defense systems. Whether you are a busy engineer, a technical expert or a project manager, you can enhance your understanding of complex systems in a short time. ABOUT ATI AND THE INSTRUCTORS Our mission here at the ATI is to provide expert training and the highest quality professional development in space, communications, defense, sonar, radar, and signal processing. We are not a one-size-fits-all educational facility. Our short classes include both introductory and advanced courses. ATI’s instructors are world-class experts who are the best in the business. They are carefully selected for their ability to clearly explain advanced technology. For example: Robert Fry worked from 1979 to 2007 at The Johns Hopkins University Applied Physics Laboratory where he was a member of the Principal Professional Staff. He is now working at System Engineering Group (SEG) where he is Corporate Senior Staff and also serves as the company-wide technical advisor. Throughout his career he has been involved in the development of new combat weapon system concepts, development of system requirements, and balancing allocations within the fire control loop between sensing and weapon kinematic capabilities. He has worked on many aspects of the AEGIS combat system including AAW, BMD, AN/SPY-1, and multi-mission requirements development. Missile system development experience includes SM-2, SM-3, SM-6, Patriot, THAAD, HARPOON, AMRAAM, TOMAHAWK, and other missile systems. Robert teaches ATI’s Combat Systems Engineering course Wayne Tustin has been president of Equipment Reliability Institute (ERI), a specialized engineering school and consultancy he founded in Santa Barbara, CA, since 1995. His BSEE degree is from the University of Washington, Seattle. He is a licensed Professional Engineer in the State of California. Wayne’s first encounter with vibration was at Boeing/Seattle, performing what later came to be called modal tests, on the XB-52 prototype of that highly reliable platform. Subsequently he headed field service and technical training for a manufacturer of electrodynamic shakers, before establishing another specialized school on which he left his name. Based on over 50 years of professional experience, Wayne has written several books and literally hundreds of articles dealing with practical aspects of vibration and shock measurement and testing. Wayne teaches ATI’s Fundamentals of Random Vibration & Shock Testing course. Thomas S. Logsdon, M.S For more than 30 years, Thomas S. Logsdon, M. S., has worked on the Navstar GPS and other related technologies at the Naval Ordinance Laboratory, McDonnell Douglas, Lockheed Martin, Boeing Aerospace, and Rockwell International. His research projects and consulting assignments have included the Transit Navigation Satellites, The Tartar and Talos shipboard missiles, and the Navstar GPS. In addition, he has helped put astronauts on the moon and guide their colleagues on rendezvous missions headed toward the Skylab capsule. Some of his more challenging assignments have centered around constellation coverage studies, GPS performance enhancement, military applications, spacecraft survivability, differential navigation, booster rocket guidance using the GPS signals and shipboard attitude determination. Tom Logsdon has taught short courses and lectured in thirty one different countries. He has written and published forty technical papers and journal articles, a dozen of which have dealt with military and civilian radionavigation techniques. He is also the author of twenty nine technical books on various engineering and scientific subjects. These include Understanding the Navstar, Orbital Mechanics: Theory and Applications, Mobile Communication Satellites, and The Navstar Global Positioning System. Courses Mr. Logsdon teaches through ATI include: Understanding Space Fundamentals of Orbital & Launch Mechanics GPS Technology – Solutions for Earth & Space and Strapdown Inertial Navigation Systems COURSE OUTLINE, SAMPLERS, AND NOTES Determine for yourself the value of our courses before you sign up. See our samples (See Slide Samples) on some of our courses. Or check out the new ATI channel on YouTube. After attending the course you will receive a full set of detailed notes from the class for future reference, as well as a certificate of completion. Please visit our website for more valuable information. DATES, TIMES AND LOCATIONS For the dates and locations of all of our short courses, please access the links below. Sincerely, The ATI Courses Team P.S. Call today for registration at 410-956-8805 or 888-501-2100 or access our website at www.ATIcourses.com. For general questions please email us at ATI@ATIcourses.com.
Mark N. Lewellen
Consultant/Instructor
Washington, DC
240-882-1234

Why Not Give Yourself the Gift of a Short Course this Holiday Season?

Washington, DC Monday, November 29, 2010 Is One of These Yours? Video Clip: Click to Watch When Did You Last do Something for Your Career? Since 1984, the Applied Technology Institute (ATI) has provided leading-edge public courses and onsite technical training to DoD and NASA personnel, as well as contractors. Our courses provide a practical overview of space […]
Washington, DC
Monday, November 29, 2010
Is One of These Yours?
Is One of These Yours?
Video Clip: Click to Watch
When Did You Last do Something for Your Career?
Since 1984, the Applied Technology Institute (ATI) has provided leading-edge public courses and onsite technical training to DoD and NASA personnel, as well as contractors. Our courses provide a practical overview of space and defense technologies which provide a strong foundation for understanding the issues that must be confronted in the use, regulation and development such complex systems. ATI short courses are designed to help you keep your professional knowledge up-to-date. Our short courses are designed for individuals involved in planning, designing, building, launching, and operating space and defense systems. Whether you are a busy engineer, a technical expert or a project manager, you can enhance your understanding of complex systems in a short time. You will become aware of the basic vocabulary essential to interact meaningfully with your colleagues. Course Outline, Samplers, and Notes Determine for yourself the value of our courses before you sign up. See our samples (See Slide Samples) on some of our courses. Or check out the new ATI channel on YouTube. After attending the course you will receive a full set of detailed notes from the class for future reference, as well as a certificate of completion. Please visit our website for more valuable information. About ATI and the Instructors Our mission here at the Applied Technology Institute (ATI) is to provide expert training and the highest quality professional development in space, communications, defense, sonar, radar, and signal processing. We are not a one-size-fits-all educational facility. Our short classes include both introductory and advanced courses. ATI’s instructors are world-class experts who are the best in the business. They are carefully selected for their ability to clearly explain advanced technology. Dates, Times and Locations For the dates and locations of all of our short courses, please access the links below. Sincerely, The ATI Courses Team P.S Call today for registration at 410-956-8805 or 888-501-2100 or access our website at www.ATIcourses.com. For general questions please email us at ATI@ATIcourses.com.
Mark N. Lewellen
Consultant/Instructor
Washington, DC
240-882-1234

Enabling the sharing of airspace by manned and unmanned aircraft

The Australian Research Centre for Aerospace Automation’s (ARCAA) Smart Skies project, focusing on the development of technology to enable manned and unmanned aircraft to effectively share airspace, is approaching its final milestone. The project, also involving Boeing Research and Technology-Australia, Insitu Pacific and the Queensland Government, is exploring development of three key enabling aviation technologies: […]
The Australian Research Centre for Aerospace Automation’s (ARCAA) Smart Skies project, focusing on the development of technology to enable manned and unmanned aircraft to effectively share airspace, is approaching its final milestone. The project, also involving Boeing Research and Technology-Australia, Insitu Pacific and the Queensland Government, is exploring development of three key enabling aviation technologies: an Automated Separation Management System capable of providing separation assurance in complex airspace environments; Sense and Act systems for manned and unmanned aircraft capable of collision avoidance of dynamic and static obstacles; and a Mobile Aircraft Tracking System (MATS) utilising a cost-effective radar and dependent surveillance systems. The latest flight trials included all of the project elements, including a fixed-wing UAV and a modified Cessna flying in automatic mode, flying collision scenarios with simulated aircraft. The final flight trial will take place in December this year, before project wrap-up and final reports in 2011, and, ultimately, the attempt to commercialise the Smart Skies intellectual property. ARCAA acting director Dr Jonathon Roberts said a new research project was also on the cards. The collision-avoidance research is one of two key areas in which the Civil Aviation Safety Authority (CASA) requires proof that technology in unmanned aircraft can operate in a way equivalent to human pilots. “In the future research we’re trying to hit the next problem: Smart Skies is all about collision avoidance and managing the avoidance of collisions; the next thing that CASA will require will be automatic landing systems,” Dr Roberts said. “So that if you have an engine failure or other catastrophic failure and you have to come down, you’ve got to be able to put it down in a safe place, so these will be vision systems that actually look at the ground and figure out where to land. “That’s the next thing that has to be done before UAVs can fly over populous areas.” The Smart Skies program was recently recognised at the Queensland Engineering Excellence Awards, where it won the ‘Control systems, networks, information processing and telecommunications’ category.

More information about the Russian Nerpa submarine and its accident

More information about the Russian Nerpa submarine and its accident http://www.bellona.org/articles/articles_2009/nerpa_sea_trials Part of: Pacific Fleet accidents and incidents The Nerpa Akula class sub pictured here at sea trials before its lethal accident in November. Bellona Archive Related news Russian and Indian media report accident sub was to go to Indian navy Russia starts sea trials […]
More information about the Russian Nerpa submarine and its accident http://www.bellona.org/articles/articles_2009/nerpa_sea_trials
ingress_image
The Nerpa Akula class sub pictured here at sea trials before its lethal accident in November.
Bellona Archive
The Russian Navy has successfully tested an Akula class nuclear attack submarine nine months after 20 sailors were killed and 21 more hospitalsed when the fire suppression system badly failed aboard the same submarine during trials in December, the sub’s builder and Russia media have reported. Charles Digges, 29/07-2009 The submarine accident, the worst to hit the Russian navy since 118 sailors died in 2000 when the Kursk nuclear submarine sunk in the Barents Sea, exposed the gap between the Kremlin’s ambitions and its military capabilities, giving the Navy yet another black eye. A fresh sea trial of the Soviet-designed Nerpa submarine began on July 10th in the Sea of Japan and was completed successfully, RIA quoted a source at the Amur shipyard, where the submarine was built, as saying. “The first stage of the test was completed successfully,” the source was quoted by the state-run RIA Novosti Russian news wire as saying. “The craft is in base (…) to prepare for the second stage of the test,” he said. He did not comment on when the submarine would be fully ready. Another, higher ranking official at the Amur shipyard declined to comment on the reported test when contacted by Bellona Web. The navy similarly would not officially comment on the recent Nerpa sea trials. The initial accident on the Nerpa last November was chalked up by Bellona’s Alexander Nikitin, a former sub captain in the Russian navy, to the sheer number of people aboard the submarine during it’s original sea trial. The crew of a standard Akula class submarine numbers 73, and three times as many were aboard during the accident.

This article from Reuters for readers interested in defense, submarines and underwater acoustics.

I think  this article from Reuters of interest to our blog readers interested in defense, submarines and underwater acoustics. http://www.reuters.com/article/idUSTRE5740DV20090805 WASHINGTON (Reuters) – Two nuclear-powered Russian attack submarines have been patrolling off the eastern seaboard of the United States in the first mission of its kind so close to shore in nearly a decade, U.S. […]
I think  this article from Reuters of interest to our blog readers interested in defense, submarines and underwater acoustics. http://www.reuters.com/article/idUSTRE5740DV20090805 WASHINGTON (Reuters) – Two nuclear-powered Russian attack submarines have been patrolling off the eastern seaboard of the United States in the first mission of its kind so close to shore in nearly a decade, U.S. officials said on Wednesday. CUBA PORT CALL One of the Russian submarines remained in international waters on Tuesday a couple hundred miles (km) off the coast of the United States, officials said. The second sub made a port call in Cuba in recent days, the New York Times reported, citing Defense Department officials who spoke on condition of anonymity. During the Cold War, the United States and Russia regularly sent submarines on secret missions near each other’s coasts. “It is the first time in roughly a decade that we’ve seen this kind of behavior,” Morrell said. Russia conducted a successful sea trial of the Nerpa last month in the Sea of Japan, according to the RIA news agency. During testing of the submarine in November, 20 people died and 21 were hospitalized when the fire extinguishing system was turned on in error, releasing Freon gas that asphyxiated the victims. The accident, the worst to hit the Russian navy since 118 sailors died in 2000 when the Kursk nuclear submarine sank in the Barents Sea, exposed the gap between the Kremlin’s ambitions and its military capabilities.

Sound Levels and Mammal Mitigation

The effect of mid-frequency sonar on marine mammals is a controversial topic. This was originally posted on a Navy web site. Comparing Mid-Frequency Active Sonar to a Saturn V Rocket For several reasons, it is inaccurate and misleading to claim that the sound of mid-frequency active sonar in water is equivalent to a Saturn V […]
The effect of mid-frequency sonar on marine mammals is a controversial topic. This was originally posted on a Navy web site. Comparing Mid-Frequency Active Sonar to a Saturn V Rocket For several reasons, it is inaccurate and misleading to claim that the sound of mid-frequency active sonar in water is equivalent to a Saturn V rocket. Sound levels in water and sound levels in air are expressed very differently*, and therefore comparing sound levels in water and air must be done carefully. As an example of the difference in the way sound levels are received in air versus water, note that a sound level of 120 dB sound pressure level in air (similar to a rock music amplifier 4-6 feet from the listener) can cause hearing damage or distress to humans and animals, while human divers and animals receiving 120 dB sound pressure level underwater experience no such issues. 1. Saturn V Rocket is 10x Louder: At 1000 yards (914 m) from a Navy ship, the receive level for mid-frequency active sonar is approximately 175 dB in water. At the same distance in water, a Saturn V rocket would register 197 dB. This 22 dB difference means that the Saturn V rocket would have approximately ten times greater intensity than mid-frequency active sonar at the same distance. Temporary threshold shift (TTS), which is the National Marine Fisheries Service’s baseline for non-permanent effects on marine mammals, is 195 dB, so the Saturn V rocket would have the potential to cause TTS to marine mammals at 1000 yards, whereas mid-frequency active sonar at the same distance would not. 2. Saturn V Sound is Continuous, Mid-Frequency Active Sonar Sound is Intermittent: Rocket engine noise is a continuous sound source, lasting for many minutes at a time. By comparison, sonar pings are intermittent, with each ping lasting one second or less and being repeated about every 30 seconds. Over the course of one minute, ship and animal movement at sea would make it very unlikely that a marine mammal would be exposed to even two sonar pings. By comparison, marine mammals would be far more likely to be exposed to the continuous “roar” of rocket engine sound during a similar timeframe. 3. Saturn V Frequencies Would Potentially Affect More Species: Rocket engine sound is a broadband sound, spanning as many as five octave frequencies. Sonar signals are limited to a narrow band, typically 1/3 octave frequencies or less. The greater number of frequencies from the broadband rocket sound would make it likely that more types of species would be affected by the rocket sound than by the narrow band sound of mid-frequency active sonar. *All sound levels in water are referenced to 1 microPascal (μPa). All sound levels in air are referenced to 20 microPascal (μPa), often expressed as sound pressure level (SPL). Sound waves with the same intensities in water and air have relative intensities that differ by 61.5 decibels (dB). Therefore, 61.5 dB must be added to relative intensities in air to obtain the relative intensities of sound waves in water.

Side Scan Sonar Technology with left and right side-viewing with up to 480 ft of underwater coverage

Lowrance announced today the premier of its next-generation sonar technology, the LSS-1 StructureScan(TM) sonar imaging module for Lowrance High Definition Systems (HDS), at ICAST 2009 in Orlando, Florida. Raising the bar in fish-finding technology, the sonar-imaging module is the world’s first to offer anglers a new dimension in underwater picture-like displays – side-to-side plus straight […]
Lowrance announced today the premier of its next-generation sonar technology, the LSS-1 StructureScan(TM) sonar imaging module for Lowrance High Definition Systems (HDS), at ICAST 2009 in Orlando, Florida. Raising the bar in fish-finding technology, the sonar-imaging module is the world’s first to offer anglers a new dimension in underwater picture-like displays – side-to-side plus straight down, full panoramic viewing. The innovative Lowrance StructureScan features a combination of SideScan and an exclusive new DownScan Imaging(TM) technology. SideScan provides full-screen left and right side-viewing with extra-crisp detail of up to 480 ft. (146 m) of underwater coverage that displays structure and fish targets, as well as their imaging-scan shadows. The new DownScan Imaging feature allows anglers, for the first time, to see submerged detail directly beneath their boats, providing a complete underwater picture in a screen format that is easy to interpret. With revolutionary on-screen display versatility, anglers can merge Lowrance side and down sonar scans in split-screen to view wide-area surveys and highly-defined detail. As a unique new tool, anglers can also compare DownScan Imaging with 2D sonar images in split-screen display to better distinguish fish from structure. Removing all of the guesswork common to existing fish-finding technology, the new LSS-1 delivers the highest underwater definition ever achieved with crystal-clear views in shallow and deep, freshwater or saltwater – even at speeds up to 30 mph.

Submarine Damages Towed Array Sonar

This is of interest to ATIcourses sonar group. It is clear that the towed sonar array would have detected the nearby submarine. There was not that much surface ship could do to maneuver to prevent the submarine from hitting the towed array. Conversely the submarine should have known that this class of surface ship was […]
This is of interest to ATIcourses sonar group. It is clear that the towed sonar array would have detected the nearby submarine. There was not that much surface ship could do to maneuver to prevent the submarine from hitting the towed array. Conversely the submarine should have known that this class of surface ship was towing an array. I personally doubt that this was inadvertently.
A Chinese submarine hit an underwater towed array sonar being towed by the destroyer USS John McCain on Thursday. The array was damaged, but the sub and the ship did not collide, the official said. A sonar array is a device towed behind a ship that listens and locates underwater sounds. The incident occurred near Subic Bay off the coast of the Philippines. The official, who declined to be named because the incident had not been made public, would not say whether the U.S. ship knew the submarine was that close to it. But of course the sonar knew the submarine was close, but could not maneuver to get out of the way. However, the Navy does not believe this was a deliberate incident of Chinese harassment, as it would have been extremely dangerous had the array gotten caught in the submarine’s propellers. The Navy has complained in the past that Chinese vessels, including fishing boats, have deliberately tried to disrupt U.S. naval activities in international waters near China. In one widely publicized incident in March, five Chinese vessels maneuvered close enough to the USNS Impeccable to warrant the use of a fire hose by the unarmed American vessel to avoid a collision. The Navy later released video of that incident.
http://www.cnn.com/2009/US/06/12/china.submarine/index.html

Sonar Sounds and Dolpins – This actually is favorable.

Jim’s comments This actually is favorable. First the sound levels are very high and the hearing loss was temporary. “The deafness, though, was only temporary and the dolphin was not hurt in the experiment”. “The hearing was typically restored after 20 minutes, and its loss only occurred after the dolphin was exposed to five rounds […]
Jim’s comments This actually is favorable. First the sound levels are very high and the hearing loss was temporary. “The deafness, though, was only temporary and the dolphin was not hurt in the experiment”. “The hearing was typically restored after 20 minutes, and its loss only occurred after the dolphin was exposed to five rounds of noise.” Secondly the animal was restrained, but in the wild the dolphin can move away our turn its body. The levels are equivalent to a very high level in the peak of a sonar beam. “The sound levels that we used were essentially the equivalent of if an animal is about 40 metres (yards) from the sonar source” . That would mean a source level of 203 + 32 = 235dB re 1 uPa at 1 meter. But the sound typically reduces as 20 Log (Range) from 1 to hundreds of meters. At 100 m the sound is reduced by 40 dB and at 300 m the sound is reduced by 50 dB. \Yahoo News Powerful sonar causes deafness in dolphins: study AFP/File – Dolphins swim off the coast of the Tuamotu islands in French Polynesia. Very loud, repeated blasts of … Tue Apr 7, 7:05 pm ET PARIS (AFP) – Very loud, repeated blasts of sonar can cause a dolphin to temporarily lose its hearing, according to an investigation into a suspected link between naval operations and cetacean strandings. Numerous beachings of whales, dolphins and porpoises have occurred over the past decade, prompting a finger of blame to be pointed at warship exercises. A theory is that the mammals’ hearing becomes damaged by the powerful mid-frequency sonar used by submarines and surface vessels, prompting the creatures, which themselves use sound for navigation, to become disoriented. A paper published in the British journal Biology Letters on Wednesday provides the first lab-scale investigation into this idea, although its authors stress it does not provide proof that warship sonar is to blame. Marine biologists led by Aran Mooney at the University of Hawaii exposed a captive-born, trained Atlantic bottlenose dolphin to progressively louder pings of mid-frequency sonar. The experiment took place in open water pens at the Hawaii Institute of Marine Biology and in the presence of the dolphin’s trainer. The scientists fitted a harmless suction cup to the dolphin’s head, with a sensor attached that monitored the animal’s brainwaves. When the pings reached 203 decibels and were repeated, the neurological data showed the mammal had become deaf, for its brain no longer responded to sound. The deafness, though, was only temporary and the dolphin was not hurt in the experiment, said Mooney. The hearing was typically restored after 20 minutes, and its loss only occurred after the dolphin was exposed to five rounds of noise. Each round comprised a block of three pings, with 24 seconds between each block. Other sensors showed that the dolphin’s breathing rose significantly when the sonar was turned on. “We definitely showed that there are physiological and some behavioural effects [from repeated, loud sonar], but to extrapolate that into the wild, we don’t really know,” Mooney said in an interview with AFP. “The sound levels that we used were essentially the equivalent of if an animal is about 40 metres (yards) from the sonar source,” he said. “The animal would have to be there for about two minutes or so” to get the same level of exposure as in the Hawaii experiment. “That’s a pretty long time for an animal to be there. If the sound’s pretty loud and the animal’s not used to it, he would move around, and the ship itself is moving in a different direction.” On the other hand, a cetacean that sought to escape a persistent loud sonar may not easily find an escape route, said Mooney. “In the ocean, sound doesn’t attenuate in a normal fashion. Sound can sometimes get trapped at the surface, in layers called thermoclines, at the top 100 metres (325 feet) or so. “Maybe in those conditions it’s more difficult to get away from the sound to a quieter area.” Further work is needed to figure out what happens at lower sound levels from sonar and at greater distances to see how cetaceans respond, he said.

New Sonar Design 1171 Series

UK & Canada. Kongsberg Mesotech introduces new sonar products at Ocean Business Tuesday, 31 March 2009 Two new sonar products from Kongsberg Maritime’s specialist sonar division, Kongsberg Mesotech Ltd will be on display at Ocean Business 09. The 1171 Series is a complete range of multi-frequency, fast scanning obstacle avoidance imaging and profiling sonars offering […]
UK & Canada. Kongsberg Mesotech introduces new sonar products at Ocean Business Tuesday, 31 March 2009 Two new sonar products from Kongsberg Maritime’s specialist sonar division, Kongsberg Mesotech Ltd will be on display at Ocean Business 09. The 1171 Series is a complete range of multi-frequency, fast scanning obstacle avoidance imaging and profiling sonars offering unrivalled resolution, from an industry leader in sonar technology. The 1171 Series of sonar heads has been developed to meet the requirements for both shallow and deep ocean applications. As well as the choice of operating frequencies, the new sonar heads feature faster scanning rates, improved range resolution and even clearer, sharper images, all in a more compact lighter housing. 1171 Series – Obstacle Avoidance Imaging Sonar Heads: The dual transducer design allows optimised operational configuration for both long range obstacle avoidance and shorter range imaging detail. The transducer is protected within an oil-filled, pressure compensating dome. The telemetry is RS485 and RS232 compatible and is automatically sensed and configured at start up to match the telemetry link used. The sonar head operation is configured and controlled using the MS1000 Software Processor. Other features include: -Dual transducers for multi purpose obstacle avoidance and inspection use. -Multiple frequency capability (330 to 400 kHz and 450 to 700 kHz). -Improved range and scanning rate. -Improved sampling resolution & beam foot print resulting in clearer, sharper images. -Improved Range Resolution. -Lighter 4000m depth rated design. -Optional Ethernet telemetry interface. 1171 Series – Multi Frequency Profiling Heads: The Multi-Frequency design allows optimising of the profiling configuration for different applications. Like the sonar head, the transducer is protected within an oil-filled, pressure compensating dome and the telemetry is automatically sensed and configured at start up to match the telemetry link used. The sonar head operation is also configured and controlled using the MS1000 Software Processor. -Multiple frequency capability (675kHz to 1.35 mHz). -Improved range and scanning rate. -Clearer, sharper images and a >0.5 cm range resolution. -Sample resolution of > 0.5mm. -Lighter 4000m depth rated design. -Optional Ethernet telemetry interface. Kongsberg Mesotech Ltd. is the Canadian subsidiary of Kongsberg Maritime. Today the company supplies a worldwide customer base with a range of products for military, fisheries, oilfield, scientific, and other offshore market applications. Kongsberg Mesotech’s strength lies in its unique engineering capabilities. Ongoing research and development has ensured the company’s position as a world-leader in high-resolution sonar systems, and acoustic technology. Kongsberg Mesotech manufactures over 100 models of multibeam, scanning, echo sounder, and altimeter sonar combinations.

Sonar used to locate wreckage of an airplane that crashed earlier this month

Uganda enlists help of U.S. sailors to locate plane crash wreckage By Sandra Jontz, Stars and Stripes Mideast edition, Thursday, March 26, 2009 Sandra Jontz/S&S Petty Officer 1st Class Michael Beauregard, a sonar technician stationed in Sigonella, Sicily, crouches next to side-scan sonar unmanned underwater vehicle. He and two other sailors will take three units […]
Uganda enlists help of U.S. sailors to locate plane crash wreckage By Sandra Jontz, Stars and Stripes Mideast edition, Thursday, March 26, 2009 Sandra Jontz/S&S Petty Officer 1st Class Michael Beauregard, a sonar technician stationed in Sigonella, Sicily, crouches next to side-scan sonar unmanned underwater vehicle. He and two other sailors will take three units to Uganda. NAVAL AIR STATION SIGONELLA, Sicily — U.S. Navy sonar technicians from Sigonella are in Uganda helping to locate wreckage of an airplane that crashed earlier this month killing 11 onboard. Sailors with Area Search Platoon 804, a support element to Explosive Ordnance Disposal Team Mobile Unit-8, began their work Tuesday, using unmanned underwater vehicles with side-scan sonar capability to search the depths of Lake Victoria, which at 26,560 square miles, is Africa’s largest lake. “We’ve been called to assist … to locate and map out the debris field for the aircraft and assist divers in the recovery of bodies and the flight recorders,” Chief Petty Officer Manuel Ybarra, a sonar technician who has served in the Navy for 24 years, said in a recent interview. The downed Ilyushin-76 cargo plane was en route to Mogadishu, Somalia, from Entebbe International Airport when it burst into flames and plunged into the lake after takeoff, according to a media report posted on allAfrica.com. A Burundian army general and his two senior colleagues, four Russian/Ukrainian crewmembers, a South African, an Indian and two Ugandans were killed in the crash, the site reported. http://www.stripes.com/article.asp?section=104&article=61590

Using Sonar To Measure Ice Thickness

CLEVELAND (AP) – Flanked by wide-eyed colleagues, Lorry Wagner holds tight to the line that disappears into a frigid, murky Lake Erie. The three men peer anxiously over the edge of a weather-beaten tugboat, 3-1/2 miles off Cleveland’s downtown shore. At the end of the line is an 80-pound prize – not a monster fish, […]
CLEVELAND (AP) – Flanked by wide-eyed colleagues, Lorry Wagner holds tight to the line that disappears into a frigid, murky Lake Erie. The three men peer anxiously over the edge of a weather-beaten tugboat, 3-1/2 miles off Cleveland’s downtown shore. At the end of the line is an 80-pound prize – not a monster fish, but a $20,000 sonar that measures ice thickness. It’s vital information, if wind turbines are to rise in these waters, near Cleveland’s water-intake crib. The sonar – essentially, an upside-down fish finder, Wagner says – will sit till early April, pinging out sound waves that gauge the thickness of ice overhead. To calculate the power of moving ice, Matthiesen and others at Case’s Great Lakes Institute for Energy Innovation will link the data on ice thickness with the movement of ice floes. A camera mounted nearby on the city’s water-intake crib is tracking that movement. “ Nobody has this kind of data,” said Matthiesen, a task force member. “We’ve got to have it.” http://www.chiefengineer.org/content/content_display.cfm/seqnumber_content/3762.htm

Seeking Sea Based Strategic Deterrence and Future SSBNs

I found this interesting for my underwater acoustics readers. U.S. Seeks Successor to Trident Submarine By Gerry J. Gilmore American Forces Press Service NAVAL SUBMARINE BASE KING’S BAY, Ga., Feb. 20, 2009 – The U.S. Navy has started the process to find a 21st-century successor to the Trident strategic missile submarine, senior Defense Department officials […]
I found this interesting for my underwater acoustics readers. U.S. Seeks Successor to Trident Submarine By Gerry J. Gilmore American Forces Press Service NAVAL SUBMARINE BASE KING’S BAY, Ga., Feb. 20, 2009 – The U.S. Navy has started the process to find a 21st-century successor to the Trident strategic missile submarine, senior Defense Department officials said here yesterday. “We’re just at the opening phases right now, going through the proper systems engineering that will advance that particular design approach,” Secretary of the Navy Donald C. Winter told reporters at a news conference. Tridents are nuclear-powered, Ohio-class submarines. At 560 feet long and 42 feet wide, Tridents are the largest submarines in the U.S. Navy’s inventory. The first Trident ballistic-missile submarine, the USS Ohio, was commissioned in 1981. “A wide variety of options” are being considered for the Trident’s replacement, Winter said. However, the Navy secretary expressed his belief that the Trident system would be replaced by another undersea-going platform. “I do fully expect that it is going to be a submarine,” Winter said of the Trident’s successor. Prior to the news conference the Navy’s top leaders and the vice chairman of the Joint Chiefs of Staff were among senior officials who attended a ceremony that paid tribute to the crew of the USS Wyoming Trident strategic missile submarine. The USS Wyoming finished its 38th patrol Feb. 11, marking the 1000th completed patrol of a Trident submarine since the Ohio embarked on its initial patrol in October 1982. The Wyoming was commissioned in July 1996 and began its first patrol in August 1997. Marine Corps Gen. James E. Cartwright, the vice chairman of the Joint Chiefs of Staff, echoed Winter’s belief that the Trident’s replacement “will be a submarine.” Chief of Naval Operations Navy Adm. Gary Roughead told reporters of the resilience and independence exhibited by submariners’ families. “I think the families of our submariners are really like submariners, a special breed,” Roughead said. “And, my hat’s off to them, and they have my utmost respect and support.” The U.S. military is about to embark on its Quadrennial Defense Review and a Nuclear Posture Review, Cartwright said, to determine what types of defense capabilities will be required to maintain U.S. national security in the coming years. The QDR is performed every four years. The threats America faces during the 21st century are much more diverse and involve “a much broader spectrum of conflict against a much broader number of enemies, to include those that are not nation-states,” Cartwright told reporters. Gauging and evaluating future threats and determining what kinds of military capabilities and systems will be needed to deter them will be debated during the QDR and the nuclear posture review, Cartwright said. U.S. defense planners are now seeking “to tailor our deterrence for the types of actors that were not present during the Cold War but are going to be present in the future,” Cartwright said. And, “it will be the sailors that will make the difference in deterrence, not necessarily just the platforms,” Cartwright said of the Navy’s future nuclear-deterrent mission. The 14 nuclear-missile carrying Trident submarines based here and at other Navy ports provide more than half of America’s strategic deterrent capability, King’s Bay officials said. “The application of deterrence can be actually more complicated in the 21st century, but some fundamentals don’t change,” Air Force Gen. Kevin P. Chilton, commander of U.S. Strategic Command, said. “And, the underlying strength of our deterrence force remains the nuclear deterrent force that we have today.” The Trident submarine strategic missile force “is absolutely essential” to America’s nuclear-deterrent capability, Chilton said. “And, it’s not just to deter nuclear conflict,” he said of the Tridents’ mission. “These forces have served to deter conflict in general, writ large, since they’ve been fielded.” The U.S. government agreed to reduce the number of its strategic-missile submarines as part of the 1992 Strategic Arms Reduction Treaty. Consequently, four of the Navy’s 18 Trident submarines were modified to exchange their nuclear missiles for Tomahawk-guided cruise missiles. These vessels carry the designator SSGN. In 2006, the USS Ohio was converted into a guided-missile submarine. At the news conference, Roughead said the Navy is “really pleased” with the converted Trident submarines, which also carry a contingent of special operations troops, as well as the Tomahawks. “That [type of] submarine has performed extremely well,” Roughead said of the cruise-missile carrying Tridents. The facility here was established in 1980, replacing a closed U.S. ballistic submarine facility that had been based in Rota, Spain. In 1989, USS Tennessee was the first Trident submarine to arrive at the facility. Another Trident training facility is based in Bangor, Wash.

Vibration and Noise Control Class Offered

Media Contact: Carolyn Cordrey (888) 501-2100 ATIinfo@aol.com Vibration and Noise Control Class Offered Respected specialists Dr. Eric Ungar and Dr. James Moore will be teaching Applied Technology Institute’s “Vibration and Noise Control” course in 2009. The four-day course focuses on vibration reduction and quieting of vehicles, devices, and equipment. It will provide guidance relevant to […]
Media Contact: Carolyn Cordrey (888) 501-2100 ATIinfo@aol.com Vibration and Noise Control Class Offered Respected specialists Dr. Eric Ungar and Dr. James Moore will be teaching Applied Technology Institute’s “Vibration and Noise Control” course in 2009. The four-day course focuses on vibration reduction and quieting of vehicles, devices, and equipment. It will provide guidance relevant to design, problem solving, and development of improvements. Dr. Ungar has served as president of the Institute of Noise Control Engineering, Chairman of the Design Engineering Division of the American Society of Mechanical Engineers, and has won awards for his work on vibrations of complex structures, structural damping, and isolation. Dr. Moore developed Statistical Energy Analysis models for the investigation of vibrations and noise in complex structures such as submarines, helicopters, and cars. He has participated in the development of active noise control systems, noise reduction coating, and signal conditioning means. Both have many years of teaching. Dates and Locations: March 16-19, 2009 in Boston, MA and May 4-7, 2009 in Beltsville, MD Dr Ungar has also published a humorous Acoustics from A to Z, that is available at https://aticourses.com/sampler/Acoustics%20from%20A%20to%20Z.pdf ATI is the leader in scientific and technical training since 1984. Regisration: call 410-956-8805 / 888-501/2100 or online at www.ATIcourses.com

Whales and the Navy

Whales and the Navy By Susan Chambers, Staff Writer Tuesday, February 10, 2009 | The U.S. Navy, pressured by coastal residents has extended a comment period on its plans to double its area for training off the coasts of Northern California, Oregon and Washington. News of the Navy’s plans spread through e-mails and on blogs […]
Whales and the Navy By Susan Chambers, Staff Writer Tuesday, February 10, 2009 | The U.S. Navy, pressured by coastal residents has extended a comment period on its plans to double its area for training off the coasts of Northern California, Oregon and Washington. News of the Navy’s plans spread through e-mails and on blogs on the Internet two weeks ago as notices about public meetings were sent out. But many folks were outraged, contending there was insufficient public notice and too few public meetings. The deadline has been extended to Wednesday, Feb. 18. New national security challenges and advancement in technology make it necessary, the Navy said. “Recent world events have placed the U.S. military on heightened alert in the defense of the U.S. and in defense of allied nations,” the Navy said. The Navy started scoping meetings in 2007 to get input on its study for the training complex. The 60-day process started in July and included meetings held in September 2007. The Navy received 50 comments, 23 of which expressed concerns or opposition to the training’s impact on marine mammals, such as whales. Bruce Mate, the director of the marine Mammal Institute at Oregon State University, said in an e-mail the Navy plans to use high-energy sonar, up to 235 decibels. The National Marine Fisheries Service, he said, limits the sounds of human activities to no more than 160 decibels. Editor Note: Mate does not seem to take into account that the sound pressure level decreases with range and the acoustic intensity decreases as 1/(range squared):

Navy Sonar and Marine Mammals off Hawaii

The U.S. Navy was granted a one-year permit to train with sonar and bombs in Hawaii waters so long as it tries to protect whales and other marine animals from harm. This is a controverial topic. It is covered in a full day in ATI’s course Advanced Topics In Underwater Acoustics. http://news.yahoo.com/s/ap/20090114/ap_on_re_us/navy_whales_1 Environmental Impact Considerations […]
The U.S. Navy was granted a one-year permit to train with sonar and bombs in Hawaii waters so long as it tries to protect whales and other marine animals from harm. This is a controverial topic. It is covered in a full day in ATI’s course Advanced Topics In Underwater Acoustics. http://news.yahoo.com/s/ap/20090114/ap_on_re_us/navy_whales_1
  • Environmental Impact Considerations for Underwater Sound (Ellison) Anthropogenic sound impacts on marine animals. Permit requirements and process. US Federal Regulations, NEPA, MMPA, ESA, Magnuson-Stevens Act, Coastal Zone Management Act, National Marine Sanctuaries Act. International regulations and guidelines. Monitoring and mitigation.   
  • Marine Bioacoustics for Engineers (Ellison) Fundamentals of Marine Animal Hearing and Communication. Bioacoustic metrics. Acoustic exposure criteria for harm and significant behavior response for marine mammals. Developing criteria for fish and turtles. Behavioral testing techniques. 
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    https://aticourses.com/advanced_topics_underwater_acoustics.html

    Best Books For Acoustics

    Several years ago ATI constructed a list of recommended books for acoustics. We would like to update the list and request your suggestions of the most useful books. https://aticourses.com/acoustics_books.htm Thank you!
    Several years ago ATI constructed a list of recommended books for acoustics. We would like to update the list and request your suggestions of the most useful books. https://aticourses.com/acoustics_books.htm Thank you!

    On-Site Training at Your Facility

    An on-site course presentation, when considering travel and related expenses, will make having as little as 6-8 attendees a more economic value then having the same number attend a public seminar.
    The Applied Technology Institute offers on-site technical training at your facility. ATI’s abilityt to provide customized course presentations to a highly technical market has placed ATI as one of the leading technical seminar providers. Request a free on-site proposal with no obligation by contacting us at ati@aticourses.com