An important aid to vessel navigation and collision avoidance, Sonardyne’s Navigation and Obstacle Avoidance Sonar (NOAS) images the seabed ahead of a vessel to detect potential underwater hazards. Using sophisticated bow-mounted transducers, NOAS displays water depth, sub-surface obstacles and features by creating an accurate 3D model of the underwater environment. The model is displayed relative to the vessel, overlaid on nautical charts in real-time, providing the crew with an easily interpreted image of the underwater topography the vessel is passing through.
NOAS – Navigation and Obstacle Avoidance Sonar System
What you need to know
- Reduces the risk of underwater collisions and groundings
- Ideal for commercial, military, cruise and private vessels
- Suitable for new-build or retro fit
- Easy to integrate with existing bridge systems
- Optional intruder detection capability
More about this product
NOAS System Overview & Datasheet
NOAS is a low power, forward-looking sonar that can be operated as a standalone unit or be integrated into a vessel’s navigation system.
The sonar scans the water column and builds a 3D model of the seabed and submerged objects ahead of the vessel. The intuitive display informs the crew of the seabed terrain and any potential underwater hazards to a range of up to 600 metres over a 90 degree field of view. NOAS also has an operating mode for navigation and underwater intruder detection capability out to a range of 1,500 metres over a 180 degree field of view.
NOAS can operate as an independent system or feed fully-processed sonar images into, and be controlled by, the vessel’s integrated navigation system. This allows the crew to customise the operator display to meet the specific needs of the vessel and its mode of operation.
Consisting of two sonar arrays that are mounted in the bow of the vessel, NOAS is designed to be retro-fitted to existing vessels as well as new vessels. Comprehensive engineering support and advice is available from Sonardyne to support installation and commissioning.
NOAS scans the water column ahead of the vessel in both vertical and horizontal planes to provide a 3D model of the seabed and objects in the water column. This is displayed in an intuitive user interface that can be manipulated by the operator to offer alternative views of the water column.The display is designed to be used to aid navigation, showing the water depth and potential underwater hazards overlaid in real-time with the vessel’s position and chart information.The screenshots above are representative of NOAS’ 3D operating mode, with the Main View window illustrating how sonar data builds a model of the underwater environment.
Alerts can be configured to warn of potential collision hazards or shallow water. These can be based on depth, distance from the vessel and time to impact. Multiple alerts can be programmed and are displayed in the profile view and depth scale.
Sonar imagery is temporarily retained on the display providing the operator with a recent history of the vessel’s passage. This feature can be particularly useful when manoeuvring as the depth of the water and potential hazards are displayed even when outside of the sonar’s current field of view. The chart layers can be enabled and disabled. In addition, the operator can also choose to display range rings or range markers as required by the vessel’s crew.
A window in the display shows a profile view of a slice through the depth data ahead of the vessel. The profile can be steered to port or starboard by the user.
The Overview Window shows the current position and historical track of the vessel on a smaller scale North-up chart, along with the vessel’s current latitude, longitude and heading, as received from the ship’s navigation aids. NOAS can also have a 2D display which is colour-coded to represent depth with blue being deepest and red for shallow water or objects.
The NOAS underwater hardware consists of a sonar head and a projector. Sonardyne can also provide a mounting frame to enable NOAS to be easily installed in a ship’s bow. Sonardyne’s highly experienced engineering team can work with owners to design bespoke mounting arrangements.
The main subsea housing contains the receiver array and all the front-end electronics and processing. NOAS feeds fully-processed sonar images to the NOAS processor located on the vessel’s bridge. The optimum position to mount the NOAS system is behind an approved and tested, acoustically transparent ‘window’ in the vessel’s bow.
|Range / Field of View||75m, 150m, 300m, 600m, @ 90° (Depth mode)
25m to 150m x 180°, 300m @ 120°, 600m to 1500m @ 90° (Sonar mode)
1,500m @ 180° (Intruder Detection mode)
600m (3D imaging)
1,500m (Obstacle avoidance
|Operational Speed||Up to 25 knots|
|Weight in Air||95 kg (Sonar array), 11.5 kg (Projector)|
|Chart Overlay||ENCX. Supports ENC (S-57), ARCS, NOAA RNCs|
|Bottom Mapping Ratio||Up to 20x water depth|
|Maximum Depth Detection||50 metres below keel|
|Power Requirements||<150 Watts|
|Operating Frequency||70 kHz with 20 kHz bandwidth|
|Maximum Output Power||208 dB re 1µPa @ 1m|
|In-Water Target Ping Stabilisation||208 dB re 1µPa @ 1m|
|Maximum Output Power||Yes|
|User Definable Automated Alarms||Yes|
|Display of Ship’s Navigation Information||Latitude, Longitude and Heading|
|Operating System||Windows 7|
|Integration into 3rd Party ECDIS/ECS||Multi-vendor|