HELRAS or the Helicopter Long Range Active Sonar is a
naval helicopter undersea sensor, a dipping
sonar
Sonar (sound navigation and ranging or sonic navigation and ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, measure distances ( ranging), communicate with or detect objects on ...
(a form of
towed array sonar
A towed array sonar is a system of hydrophones towed behind a submarine or a surface ship on a cable. Trailing the hydrophones behind the vessel, on a cable that can be kilometers long, keeps the array's sensors away from the ship's own noise sou ...
), deployed by
helicopter
A helicopter is a type of rotorcraft in which lift and thrust are supplied by horizontally spinning rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forward, backward and laterally. These attribut ...
s of many
naval air forces
Commander, Naval Air Forces ( COMNAVAIRFOR, and CNAF; and dual-hatted as Commander, Naval Air Force, Pacific, and COMNAVAIRPAC) is the aviation Type Commander (TYCOM) for all United States Navy naval aviation units. Type Commanders are in Admin ...
around the world to detect
submarines; it is a form of
geophysical MASINT
Geophysical MASINT is a branch of Measurement and Signature Intelligence (MASINT) that involves phenomena transmitted through the earth (ground, water, atmosphere) and manmade structures including emitted or reflected sounds, pressure waves, vibra ...
.
History
HELRAS was first developed in the 1970s by
Bendix, FIAR and
British Aerospace
British Aerospace plc (BAe) was a British aircraft, munitions and defence-systems manufacturer. Its head office was at Warwick House in the Farnborough Aerospace Centre in Farnborough, Hampshire. Formed in 1977, in 1999 it purchased Marconi ...
. Another rival system was called FLASH (Folding Light
Acoustic System for Helicopters). In the 1980s, the system was supplied by Bendix.
A competitor of HELRAS is the
Low Frequency Active Sonar
Sonar (sound navigation and ranging or sonic navigation and ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, measure distances ( ranging), communicate with or detect objects on ...
(LFAS).
Capability
It can detect submarines up to 60NM.
Manufacture
Parts for the system are made by
Rolls-Royce North America
Rolls-Royce North America, Inc. is a subsidiary of multinational corporation Rolls-Royce plc. The American unit operates under a Special Security Arrangement which allows it to work independently on some of the most sensitive United States de ...
.
Deployment
The system has been fitted to EH101, S70B, NH90, CH-148, AS532SC, AB412, and AS565 with helicopter of navies such as Italy, Turkey, Greece, Netherlands, Canada, Singapore, Thailand, Chile, Brazil, Indonesia, and Morocco. The system has also been fitted to unmanned surface vessels Seagull and RHIBs for Israel and USN.
See also
*
AN/SQQ-89
*
HIDAS, made by
Selex GalileoHIDAS
/ref>
* Light Airborne Multi-Purpose System
The Light Airborne Multi-Purpose System (LAMPS) is the United States Navy's program that develops crewed helicopters to assist the surface fleet in anti-submarine warfare.
The purpose of LAMPS is to scout outside the limits of a fleet's radar an ...
* Searchwater (radar)
Searchwater was a maritime surveillance radar developed by Thorn EMI under project P1149. This type of radar has been in service with the Royal Air Force Hawker Siddeley Nimrod aboard the MR2 variant since the 1970s.
The retirement of the Roya ...
, made by Thales UK
* SOSUS
The Sound Surveillance System (SOSUS) was a submarine detection system based on passive sonar developed by the United States Navy to track Soviet Navy, Soviet submarines. The system's true nature was classified with the name and acronym SOSUS them ...
* USHUS
References
Anti-submarine warfare
Helicopter components
Military sonar equipment of the United States
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