SHIP WEAPONS
TORPEDOES
VERTICAL LAUNCH ASROC (VLA)
BRIEFING: The VLA is a missile designed to deliver the Mk46 Mod
5 torpedo to a water-entry point. It is intended to provide vertical-launch-capable surface combatants with an all-weather, 360-
degree, quick reaction, standoff anti-submarine weapon capability.
VLA includes a solid-propellant booster with thrust vector control
to guide the missile from a vertical orientation through a pitch-over
maneuver into a ballistic trajectory intended to deliver the torpedo
to a point on the ocean surface. It is launched from the MK 41 VLS.
All VLAs were upgraded with the Mk46 Mod 5A (SW) torpedo that provides improved performance in shallow water. The
VLAs were being upgraded with the Mk54 Mod 0 torpedo
beginning in 2010. VLA, deployed on Ticonderoga-class cruisers and Arleigh Burke-class destroyers, has had its service life
extended to 2017. In 2012, Lockheed Martin was awarded a
contract to restart production of VLA.
LENGTH:...................... 16. 7 feet
DIAMETER: .................. 14. 1 inches
WEIGH T: ....................... 1,650 pounds
RANGE:........................more than 10 miles
PROPULSION: .............solid-propellant rocket
WARHEAD WEIGHT:..... 96. 8 pounds, high-explosive
CONTRACTOR: ...........Lockheed Martin MS2
MK48 TORPEDO
BRIEFING: The Navy uses Mk48 heavyweight torpedoes only in
submarines, employing them as a primary anti-submarine and anti-surface weapon. The Mk48 torpedo also has been acquired by three
allied countries. With a need to continue torpedo performance upgrade programs to counter continuously evolving threats, the Navy
developed the Mk48 Mod 5 ADCAP torpedo with greater speed and
accuracy than any submarine-launched torpedo in the Navy’s history. It is a heavyweight acoustic-homing torpedo with sophisticated
sonar, all-digital guidance-and-control systems, digital fusing systems and propulsion improvements. Its digital guidance system
allows for repeated improvements to counter evolving threats
through software upgrades. The last new ADCAP torpedo was delivered in 1996. The Navy intends to restart Mk48 production in 2016.
To improve future performance, several upgrades are being made
to the existing ADCAP inventory. Details of the upgrades follow:
n Mk48 Mod 6 ADCAP
The Mk48 Mod 6 ADCAP — which reached IOC in 1997 — com-
bines two improvements: one in guidance and control (G&C
Mod), the other in the torpedo propulsion unit (TPU Mod). The
G&C Mod improves the acoustic receiver, replaces the guidance-
and-control set with updated technology, increases memory and
improves processor throughput to handle the expanded software
demands required to improve torpedo performance against evolv-
ing threats. The TPU Mod provides a tactically significant reduc-
tion in torpedo radiated-noise signatures.
The Mod 6 is the first torpedo to use the Torpedo Downloader
System that can provide rapid software updates to embarked
weapons, allowing the submarine to deploy with the most up-to-
date software version. The latest improvement to the Mod 6 was
fielded in 2009.
n Mk48 Mod 7 Common Broadband Advanced Sonar
System (CBASS)
The CBASS was jointly developed with the Royal Australian
Navy. It includes a new broadband sonar system and its associ-
ated software to achieve significant increases in operating band-
width. The system also includes new broadband processing
algorithms to improve counter-countermeasure and shallow-
water performance while retaining deep-water performance
characteristics. The CBASS torpedo reached IOC in 2006.
LENGTH:...................... 19 feet
DIAMETER: .................. 21 inches
WEIGH T: ....................... 3,520 pounds
SPEED:.........................more than 28 knots
RANGE:........................more than 5 miles
DEPTH:........................greater than 1,200 feet
PROPULSION: .............liquid propellant, piston engine, pump jet
WARHEAD WEIGHT:.....650 pounds, high-explosive
CONTRACTOR: ...........Raytheon Integrated Defense Systems
COUNTERMEASURE ANTI-TORPEDO
(CAT)
BRIEFING: The CAT is a small torpedo designed to intercept
and destroy anti-ship torpedoes. Designed by Pennsylvania
State University, it is a component of the Surface Ship Torpedo
Defense System (SSTD). The SSTD’s Torpedo Warning System
(TWS) includes a Target Acquisition Group, a Tactical Control
Group and a CAT launcher. The TWS detects the incoming torpedo and launches the CAT.
An engineering and development model (EDM) of the CAT
and SSTD were tested in May 2013 from USS George H. W. Bush
and deployed in 2014. A roll-on/roll-off model is being deployed
on USS Theodore Roosevelt and USS Dwight D. Eisenhower. A
second EDM will be installed on USS Harry S. Truman. The
Navy plans to equip all aircraft carriers and other high-value
ships with the SSTD by 2035.
MK67 SUBMARINE-LAUNCHED
MOBILE MINE (SLMM)
BRIEFING: The SLMM was developed to destroy enemy shipping in shallow-water areas inaccessible for other mine deployment techniques or for covert mining of hostile environments.
The SLMM is a shallow-water mine consisting basically of a
modified Mk37 torpedo. Some Mk67s were removed from the
serviceable inventory in 2012.
LENGTH:...................... 161 inches
DIAMETER: .................. 19 inches
WEIGH T: ....................... 1,658 pounds
GUIDANCE SYSTEM:...magnetic/seismic target detection devices
WARHEAD WEIGHT:.....510 pounds, high-explosive
U.
S.
N
AV
Y
MK54 LIGHTWEIGHT TORPEDO
U
.
S
.
N
A
V
Y
