Description

The AN/BPS-15 is a submarine radar system primarily designed for surface search and navigation, with additional capabilities for limited air warning. The system was service-approved in May 1971, marking its official introduction into the U.S. Navy’s submarine fleet. Soon the AN/BPS-15 became a standard in all U.S. submarines, except for later units of the Ohio class and the Seawolf class.

It operates in the X-band frequency, utilizing a horn array antenna to actively detect contacts when the submarine is surfaced, although its main function is navigation. The radar also can transmit through periscope #1. This allows a visual search and a radar search to be conducted concurrently.

The AN/BPS-16 is an improved version of the AN/BPS-15.

Variants

The AN/BPS-15 has evolved through several variants, with improvements mainly in their mounting and display technologies.

• AN/BPS-15 – Initial variant.
• AN/BPS-15A – Initial version installed in Los Angeles-class submarines (SSBN 688)
• AN/BPS-15B – Initial variant installed in Trident submarines (SSBN 726-740)
• AN/BPS-15D – Variant for Lafayette-class submarines (SSBN-616)
• AN/BPS-15E – Variant for submarines converted to special operations role.
• AN/BPS-15H – Commercial off-the-shelf (COTS) variant used for replacement in Los Angeles-class submarines. It includes software and hardware upgrades for ECDIS-N compliance.
• AN/BPS-15J – It features a modern 20-inch flat screen, a significant upgrade from the earlier cathode ray tube (CRT) displays. Replacement in Ohio submarines with the -15B variant.

Operational Status

Operational in the following Platforms:

• SSBN 730-740 (BPS-15J)
• SSGN 726-729 (BPS-15J)
• SSN 688 (some ships; BPS-15H)

Contractor

• Initially, Sperry Marine, Charlottesville, Virginia, USA
• Currently, Northrop Grumman Sperry Marine.

Specifications

Role: Surface search/navigation
Frequency: X-Band
Antenna dimensions: 40 in (101 cm) (aperture)
Antenna weight: 168 lb (76.2 kg)
Minimum range: 25 yd (23 m)
Range resolution: 30 yd (27.4 m) (in short pulse mode): 100 yd (91.4 m) (in long pulse mode)
Beam: 3 x 13 deg
Peak power: 35 kW
Antenna gain: 29 dB
Pulsewidth: 0.1/0.5 με
Pulse repetition frequency (PRF): 1,500/750 pps
Scan rate: up to 9.5 rpm

Further reading

• Ohio-Class (SSBN-726) Ballistic Missile Submarines
• Ohio-Class (SSBN-726) Submarine Technical Specification

Bibliography

• Jane’s Major Warships Volume 1. (1997). United Kingdom: Jane’s Information Group.
• Jane’s – Jane’s Underwater Warfare Systems 2000-2001 (2000). United Kingdom: Jane’s Information Group.
• Polmar, N. (2013). The Naval Institute Guide to the Ships and Aircraft of the U.S. Fleet. United Kingdom: Naval Institute.