Benefits of the High-Performance Low Frequency Active Sonar Source:

• Deployable with a receiver as a single tow configuration

• Single or dual aperture configurations

• Independent transmissions per aperture

• Focused-beam, sector, or omnidirectional transmissions

• Includes health monitoring with continuous built-in test

• Full power operation at shallow depth

• Winch reelable

Maritime Systems

As Low Frequency Active (LFA)-capable platforms become smaller and multi-role ships become more prevalent, sonar system size and weight become increasingly important.

Ultra’s unique reelable Horizontal Projector Array (HPA) addresses this problem head-on. The HPA is an array of multiple in-line, independently driven projectors in an oil-filled hose. The HPA and its tow cable can be stored on, and deployed directly from, a single winch without needing the additional space and weight of a separate overboarding system.

Given that the HPA is towed on the same cable as the receiver array (e.g. Ul-tra’s QUAD® LFA receiver array), a single winch is used to handle both the trans-mitter and receiver components. This approach leads to a smaller, lighter, and less expensive solution than the tra-ditional Variable Depth Sonar towed body. A single winch system based on the HPA can be containerized for easy installlation on multi-role platforms. When operating in littoral waters, the HPA offers advantages over more tra-ditional towed bodies that employ a small number of high power projectors.

Since acoustic energy from each indi-vidual HPA projector is lower, the HPA operates without cavitating at shal-lower depths, thereby enabling higher power operation in littoral environ-ments. The HPA directional transmit ca-pability allows it to focus energy in the directions of interest, avoiding known reverberation sources, and avoiding ar-eas of concern (e.g. marine mammals).

The HPA is typically configured to oper-ate in one or two frequency bands. The aperture and design frequency can be customized to suit individual unique customer requirements. When two ap-ertures are included, they are configured as separate parts of the array that can be independently operated. For exam-ple, one can be used for target track-ing while the other is used to search.

Because each individual projector is independently driven, HPA transmit waveforms can be phased to steer energy along conventional beams. Ultra’s on-board Transmit Control-ler can also create defocussed sec-tor or omnidirectional transmissions.

A variant of Ultra’s HPA is in ser-vice with the Royal Australian Navy.

High-Performance Low Frequency Active Sonar Source

Ultra Electronics Underwater Warfare

LFA HORIZONTAL PROJECTOR ARRAY

Sold to:

Ultra Electronics Underwater Warfare

LFA Horizontal Projector ArrayTechnical Specifications

Ultra Electronics Maritime Systems Inc.

is a wholly owned subsidiary of Ultra

Electronics Holdings plc. UK.

Ultra Electronics reserves the

right to vary these specifications

without notice.

© Ultra Electronics Inc. 2019

BR817483 v2

Printed in Canada

Ultra ElectronicsMARITIME SYSTEMS40 Atlantic Street Dartmouth Nova Scotia B2Y 4N2 CanadaTel: +1 902 466 7491Email: info@ultra-ms.comwww.ultra-ms.com www.ultra-electronics.com

Pulse Types1.............................User definable within the operational bandwidth

Maximum Bandwith1................................................Up to 20% of centre frequency Maximum Pulse Duration1..............................................................................16 seconds Number of elements per aperture.......................................................32 (maximum)

Operating Frequency...........1.5 kHz to 3.5 kHz (depending on configuration) Source Level1...............................................up to 225 dB re 1μPa at 1m broadside Length1...................................................................................................40 m (131.234 ft)

Diameter..............................................................................................120 mm (4.724 in) Minimum Bend Radius.......................................................................0.75 m (2.461 ft) Maximum Operating Depth.........................................................200 m (656.168 ft)

Operational Temperature2........................................................................-20C to +350C

Notes1 - For typical configurations2 - In seawater

Omni, sector, and focussed beam patterns for a 16λ HPA

HPA Calibration at the USN Seneca Lake Sonar Test Facility