HELRAS (Helicopter Long-Range Active Sonar)

-

 

Photo Credit: L3HARRIS

Overview

  • A highly capable, interoperable, and versatile sonar weapon system.
  • Reduces operating costs by minimizing Anti-Submarine Warfare mission time.

Key Features

  • Highest-performance dipping sonar tested against diesel-electric and nuclear submarines.
  • Operates at 1.38 kHz nominal frequency for long-range detection and tracking.
  • Lightweight system with high source levels, narrow vertical beams, and high array gain (≥14 dB higher than medium-frequency systems).
  • Patented compact acoustic transducers and expandable transmitting/receiving arrays.
  • High-resolution Doppler processing with CW pulses (up to 10s) and FM pulses (up to 5s).
  • Interoperable with sonobuoys and modern low-frequency towed variable depth sonars.
  • Reduces operating costs through long-range detection and large-area search rates.

Performance Advantages

  • Increased figure of merit.
  • High-resolution Doppler processing.
  • Stand-alone or fully integrated operation.
  • Low-frequency performance advantage.
  • Technological innovations.
  • Bistatic and multistatic interoperability.
  • Reduced operating expense.

Capabilities

  • Ping-to-ping integration.
  • Contacts and tracks.
  • Classification database.
  • Built-in acoustic model (“range of the day”).
  • Directional audio.
  • Auto deployment.

Operating Modes

  • Active Mode: CW, FM, combo.
  • Passive Mode: Broadband, narrowband, ALI, DEMON processing.
  • Communication Mode: STANAG-1074 underwater telephone.
  • Playback Mode: Recorded data for analysis and training.
  • Multistatic Mode: Transmit/receive with elliptical equation displays.
  • Test Mode: Power-up, continuous, and initiated built-in test.

Active Mode Details

  • Shaped CW pulses (0.039–10 sec) at 1,311 / 1,380 / 1,449 Hz.
  • Linear FM pulses (0.156–5.0 sec).
  • FM triplet (0.625–1.25 sec).
  • 50 Hz downsweep at 3 center frequencies.
  • 100 Hz downsweep at 3 center frequencies.
  • 300 Hz downsweep at 1 center frequency (1,380 Hz).
  • Combo FM/CW (0.625–2.5 sec).
  • Displays: PPI, bearing range, Doppler range, A-scan FM, all beam Doppler.

Range Scales

  • 1, 1.5, 2.5, 4, 6, 10, 16, 25, 40, 60 nautical miles.

Passive Mode

  • Bandwidth: 800–2,000 Hz.
  • Broadband, narrowband, ALI, DEMON processing.
  • Bearing time record, bearing frequency indicator.
  • NALi, DEMON, LOFAR, waterfall displays.

Technical Specifications

  • Source Level: 219 dB re 1 µPa @ 1 yd.
  • Depth: 500 m.
  • Transmit Array: Vertical 15° (steerable ±15°), horizontal omni, 7-projector expandable line array (5.2 m height).
  • Receive Array: Vertical ±19.5°, horizontal 32 half beams / 16 full beams, expandable volumetric array (2.6 m diameter, 1.2 m height).


Popular News

AIM-260 Enters Production: Could This U.S. Missile Outclass China’s PL-15

-
Image
The AIM-260 Joint Advanced Tactical Missile (JATM) is poised to enter production, marking a new chapter in the evolution of air-to-air warfare. After years of secrecy and speculation, the U.S. Department of Defense has publicly requested funding for the procurement of the AIM-260A in its Fiscal Year 2026 budget—a move that signals the missile’s transition from development to operational readiness. A Missile Born of Strategic Necessity The AIM-260 program began in 2017, driven by the need to counter emerging threats, particularly China’s PL-15 long-range air-to-air missile. The PL-15, equipped with a dual-pulse rocket motor and advanced guidance systems, posed a serious challenge to U.S. air dominance. In response, the U.S. Air Force and Navy initiated the JATM program to develop a missile that could not only match but exceed the capabilities of the AIM-120 AMRAAM, the current workhorse of American air-to-air engagements. Budget Breakdown and Production Plans For the first time, the U.S...
Read more »

Denmark Confirms Permanent Acquisition of NASAMS, IRIS-T, MICA and SAMP/T Air Defence Systems

-
Image
The Danish Ministry of Defence has confirmed that its interim solution for short and medium-range air defence will now be converted into a permanent capability, marking a significant step in strengthening the nation’s integrated air defence architecture. The acquisition includes two NASAMS batteries from Kongsberg, two IRIS-T SLM systems from Diehl, and two VL MICA systems from MBDA, ensuring a layered and versatile shield against aerial threats. In addition, Denmark will procure two long-range SAMP/T systems from MBDA, further enhancing its ability to counter high-end threats and contribute to NATO’s collective defence posture. NASAMS. Photo: kongsberg.com IRIS-T SLM. Photo: hensoldt.net VL MICA. Photo: mbda-systems.com SAMP/T The decision to move from leased or temporary arrangements to permanent acquisitions underscores Copenhagen’s commitment to building a robust and sovereign air defence capability. NASAMS, already widely deployed among NATO allies, will provide Denm...
Read more »

L3Harris Advances MK-48 Torpedo Tech with New Fiber-Optic Cable for U.S. Navy

-
Image
L3Harris Technologies has successfully passed a critical milestone in the development of its advanced fiber-optic torpedo cable system, known as the Improved Post-Launch Communications System (IPLCS). This achievement, marked by the completion of the Proof of Design (POD) phase, signals a significant leap forward in undersea warfare capabilities for allied naval forces. The IPLCS is now poised to enter full-scale production, ready to be deployed by both the United States Navy and the Royal Australian Navy. Photo: l3harris.com The IPLCS represents a transformative upgrade over legacy copper wire systems traditionally used to guide torpedoes. By replacing outdated copper cables with ultra-thin fiber-optic lines—comparable in thickness to a 20-pound fishing line—L3Harris has introduced a solution that is exponentially more capable. Despite its slender profile, the fiber-optic cable offers thousands of times more bandwidth, vastly improved reliability, and extended communication range. Th...
Read more »

BOXER Skyranger30

-
Image
  Photo Credit: RHEINMETALL Overview Highly mobile air defence system designed to counter drones and aerial threats. Integrates active search and passive tracking sensors. Equipped with both gun and missiles for autonomous engagement. Special focus on small uncrewed aerial targets. Capable of defeating agile single or swarming threats performing loiter, pop-up, or dive attacks. Provides a lethal, mobile, and protected wheeled air defence platform. Main Features Highly mobile air defence system adopted by NATO countries. Latest development focusing on small aerial targets. High protection combined with superior mobility. Firepower: 30mm Oerlikon Revolver Cannon KCE-ABM and VSHORAD missiles (MISTRAL/Stinger). Simple handling and maintenance. Dimensions Length: up to 8,000 mm Width: <3,000 mm Height: <3,950 mm Combat weight: <39.5 t Performance Top speed (paved roads): >65 km/h Gradeability: 60% Side slope: 30% Trench crossing: 2,000 mm Verti...
Read more »

PUMA Infantry Fighting Vehicle

-
Image
  Photo Credit: RHEINMETALL General Concept Combines high mobility with maximum protection and firepower Flexible response at any time, location, and intensity Key Capabilities Optimum protection for crew survivability Armament for escalation and de-escalation Rapid global deployability and tactical mobility Network-centric warfare capability Sustainability under worldwide climatic conditions Built-in test equipment Integrated training system Crew Survivability Protection against symmetric and asymmetric threats Operates in conflicts of all intensity levels Supports escalation and de-escalation options Rapid global deployments under multinational command Global Mission Readiness Designed for long-distance missions under worldwide conditions Endurance for long mission times Operates even with inadequate infrastructure Protection Best combined protection against mines, IEDs, shaped charges, KE ammunition, and NBC weapons Active softkill system against ...
Read more »

HENSOLDT ARGOS‑8

-
Image
HENSOLDT ARGOS‑8 Specifications Photo Credit: HENSOLDT System Overview 8” class airborne electro‑optical system for ISR (observation) and ISTAR (targeting) Designed for Group‑2 & Group‑3 UAVs Mechanically stabilized EOS with 3 sensors Day/night operation, target range finding & designation via semi‑active laser Integral INS for geo‑location STANAG‑compliant video metadata Digital video stabilization in ISR mode Features & Benefits SWaP optimized targeting solution Day/night imaging with laser range finding Target laser designation Software‑controlled laser no‑firing zones Integral INS for geo‑pointing & geo‑location Moving target engagement with video auto‑tracker STANAG‑compliant video metadata Picture‑in‑Picture video display Mission planning, operational & debrief software Ease of integration ITAR Free Interfaces Communication Control & video: Ethernet or RS‑422 Full HD video over Ethernet 100 BaseT INS Aircraft GPS antenna ×2...
Read more »