Page 241 - NAVAL SCIENCE 3 TEXTBOOK

;\'AVr\ 1. WEAPONS AND A[UCRA r: T 247

A Navy Seahawk helicopter fires a Hellfire missile. (Mark Leonesio)

it is launched. A power~d version has a r:.1ng~ in excess of 120 nau- Navy Undersea Warfare Weapons
tical miles.
Tada)', th~ Navy's primary operational undersea wart:1re (US\·V)
There is also a guidance kit called the joint direct attack muni-
weapons ;He antisubmarine rockets (ASROC) and antisubmarine
tion (JOAM) that converts conventional 1.000- and 2.000-pound
torpedoes.
bombs into precision-guided munitions using the satellite-based
The ASROC is a supersonic, solid-fueled, antisubmarine bal-
CPS system for guidance. \Veapons of this type are often referred
listic missile, carried by Aegis cruisers and Arleiglt Burke-class
to as smart bombs, to distinguish them from older unguided bombs
destroyers, and fired from vertical launch tubes. The purpose of
that follow ballistic trajectories after being released from the deliv-
ASROC is the destruction of enemy submarines;]t long ranges. It
ering aircraft.
does this by the deliveq· of a homing torpedo through the air to n
point in the water frolll which it can begin a search pnttern to find
and home in on the target submi1rine. An ASROC-equipped US\V
ship (;11\ launch its weapolls before the submarine is even aware
that it is under attack.
In addition to ASROC. the Nav)' has several other models of
US\ Ii torpedoes that can be launched b)' surl,,,e ships and b)' heli-
copters. All of these are homing torpedoes guided by the sound of
the vessel being attacked or by reflected echoes from it. They are
powered by electric motors and batteries. They contain acoustic
homing devices, operating either in an <'Ictive or passive Illode. The
active acollstic torpeno is not dependent upon the sOllnd emitted
from the target for its homing illform;ltion. The torpedo itself gen-
erates and transmits <lcollstic pulses, some of which i.ne reflected
from the target. The returning echoes guide the torpedo to the tar~
get. The passive acoustic Impeno homes in on the noise emitted
ti·olll the target. It C<'lll often be evaded by the use of simple noise-
maker-type colintermeaSllI'es, or the submarine can reduce speed
An aviation ordinanceman arms a Maverick missile on a F/A- 18 or stop ill order to quiet sources of noise. 1-IOIning torpedoes of
Hornet. (Gretchen Roth)
both types Gl l1 be laullChed from Sllbillarincs, surface vessels such
as destroyers and cruisers, and helicopters.