Sonar is a technique that uses sound to navigate, communicate with or detect other vessels, and to observe the distance and velocity of underwater objects. The acoustic frequencies used vary from extremely low (infrasonic) to very high (ultrasonic). The word “sonar” also describes the equipment used to gather and analyze acoustic information. Sonar is used in depth sounding, fish finding, seafloor mapping, Doppler navigation, and acoustic location systems for divers. The term for the scientific study of underwater sound is hydroacoustics.
Three types of technology are categorized as "sonar":
- Passive sonar uses receiving sensors to listen for and analyze the sound made by vessels
- Active sonar uses an acoustic projector to emit pulses of sounds and a receiver which detects the echoes to find the range, bearing and relative motion
- Acoustic communication systems use a projector and receiver at both ends of the acoustic path
Sonar was first proposed as a means of detecting icebergs, but government interest in and funding of sonar systems did not take off until World War I highlighted the threat posed by submarine warfare. Modern technological innovations have included rapid-scanning and side-scan sonar, the echo sounder (or depth detector,) and within-pulse electronic sector scanning sonar (or WPESS). Military uses of sonar include systems used in acoustic homing torpedoes, in acoustic mines and mine detection.
ROV Deployed on WWII Era Wreck
Global Diving and Salvage Inc. has been contracted by the United States Coast Guard to determine if oil is present aboard the sunken ship S.S. Montebello, which sits 900 feet below the ocean surface approximately 6.5 miles off the coast of Cambria, California.
The S.S. Montebello sank after a Japanese submarine torpedoed the large oil tanker on December 23, 1941. The vessel broke apart landing upright with her bow separated from the majority of the wreckage
JCSSG Ships Train in Hawaii
USS John C. Stennis Strike Group (JCSSG) ships commenced an undersea warfare exercise (USWEX) in the Hawaiian operating area on Monday as part of the strike group's final test and evaluation before arriving in the U.S. 7th Fleet area of responsibility (AOR) and western Pacific Ocean.
Exercises like this are conducted several times throughout the year in the waters near Hawaii for maritime commanders to asses the undersea warfare capabilities of deploying strike groups.
ROV Sent to Determine Oil at 900 Feet
ROV will be used in an attempt to determine if oil is present on sunken WWII tanker.
Global Diving and Salvage Inc. has been contracted by the United States Coast Guard to determine if oil is present aboard the sunken ship S.S. Montebello, which sits 900 feet below the ocean surface approximately 6.5 miles off the coast of Cambria, California. The S.S. Montebello sank after a Japanese submarine torpedoed the large oil tanker on December 23, 1941
NOAA Fairweather Departs on Survey Mission
NOAA Ship Fairweather, a 231-foot survey vessel, departed Kodiak, Alaska, today on a mission to conduct hydrographic surveys in remote areas of the Arctic where depths have not been measured since before the U.S. bought Alaska in 1867.
NOAA will use the data to update nautical charts to help mariners safely navigate this important but sparsely charted region, which is now seeing increased vessel traffic because of the significant loss of Arctic sea ice.
Atlas Elektronik Demos New MCM Tech
ATLAS ELEKTRONIK has set a milestone in mine countermeasures (MCM) technology. With the C-IMCMS, the company has presented another first: an MCM system that operates exclusively with unmanned units.
For the first time, the complete functional chain of unmanned mine countermeasures – both for minehunting and for influence sweeping – was demonstrated by means of remote-controlled or autonomous systems
WESMAR to Introduce New Fin for Yachts
WESMAR (Western Marine Electronics) will introduce a 50-square-foot mega fin at the Fort Lauderdale Boat Show on October 27-31 in Florida.
Designed for luxury yachts, charter and super yachts, these new fins, coupled with WESMAR’s triple axis digital DSP4800 control electronics, are designed to reduce up to 90% of vessel roll. They are rugged with a neutrally buoyant design that adds lift, and are designed with added strength and reliability to meet the high performance requirements of vessels up to 250+ feet.
Ambitious Students Participate in "Project Shiphunt"
Sony and Intel’s Project Shiphunt team of young explorers, scientists and historians has returned to shore with news of its underwater discovery: shipwrecks of the schooner M.F. Merrick and the steel freighter Etruria, in deep water off of Presque Isle in Lake Huron. The project was completed with “much thanks to pings, processing and 3D,” according to one marine archaeologist. Current Media, the Peabody-and Emmy Award-winning independent television and online network founded in 2005, will air their adventure as the hour-long special, “Project Shiphunt,” on August 30th at 10 p.m. ET.
NOAA Ship Rainier Returns to Alaska for Sea Floor Surveys
NOAA Ship Rainier returns to Alaska to conduct sea floor surveys in support of safe navigation.
NOAA Ship Rainier has begun a month long survey of the sea floor near Alaska’s Prince of Wales Island as part of a multi-year effort to update nautical charts for the area. In addition to supporting marine navigation, data acquired by the 231-foot hydrographic survey vessel will also support marine ecosystem studies and improve inundation models for areas vulnerable to tsunamis. “We are pleased to return to Alaska to continue these important surveys, which will ensure the safe navigation of mariners who rely on the area’s waters for fishing, cargo delivery and recreational uses
Navy Welcomes William P. Lawrence to the Fleet
The Navy welcomed guided-missile destroyer USS William P. Lawrence (DDG 110) into the fleet during a commissioning ceremony in Mobile, Ala., June 4.
The newest Arleigh Burke-class ship, the 60th of its class, is named in honor of the late Vice Adm. William P. Lawrence, a highly-decorated Naval aviator and Vietname prisoner of war.
Lawrence began his naval career as an academic scholar and athlete at the U.S. Naval Academy, where he later returned to occupy the Chair of Naval Leadership after retiring from active duty, Feb. 1, 1986.
WESMAR Introduces Precision Beam Stabilization
Advanced design holds sonar beam steady even in rough seas adding effective distance and increasing search coverage.
WESMAR, long the leading U.S. sonar manufacturer has never lost sight of the need for electronic soundbeam stabilization. Today, after four years of intensive design, drawing on the company’s five decades of sonar leadership, President Bruce H. Blakey announced the introduction of a new sonar, the HD860 series, with Precision Beam Stabilization. “The value of this advancement cannot be overstated,” said Blakey