BRIEFING: Rescue 21 is the Coast
Guard’s advanced command, control
and communications system, engineered to better locate mariners in
distress and save lives and property at
sea. By harnessing state-of-the-market
communications technology, Rescue
21 enables the Coast Guard to execute
its missions with greater agility and
The Rescue 21 Very High Frequency
(VHF) Frequency Modulated communications system replaces the legacy
National Distress Response System
deployed in the 1970s. One of the most
significant improvements is Rescue
21’s ability to provide an approximate
position of a caller in distress, thereby
greatly reducing search times. This is
achieved through lines of bearing to the
source of the VHF radio transmission.
According to statistics supplied by the National Search
and Rescue School, a training facility run by the Coast Guard,
roughly 95 percent of all search-and-rescue cases take place
within 20 nautical miles offshore. The Rescue 21 system is
designed to capture distress radio transmissions to a minimum of 20 nautical miles offshore. Rescue 21 capabilities
supported more than 86,000 search-and-rescue cases by the
end of 2015, and with the infrastructure currently in place it
averages 1,000 cases per month.
Rescue 21’s improved communications capabilities
upgrade playback and recording features and improve the
clarity of distress calls — for repeated listening in cases of
distorted, rushed and/or distressed transmissions. The system supports Digital Selective Calling (DSC), which allows
operators of properly registered vessels in distress to transmit
their GPS position to Coast Guard stations and nearby DSC-equipped vessels.
Rescue 21 can help restore critical communications following a disaster through the use of portable antenna towers. The
system’s direction-finding and geographic display capabilities
also help to identify and locate hoax callers, conserving valuable search-and-rescue response resources.
The system’s expanded frequency capacity enables
greater coordination and communication among all Coast
Guard mission areas and with the Department of Homeland
Security, as well as other federal, state and local agencies and
first responders. Project activities are coordinated with others to share the facility and tower infrastructure with other
Coast Guard command-and-control projects, such as the
Interagency Operations Center and the Nationwide Automatic
Identification System project, to improve the nation’s maritime safety and security.
The system is being installed in stages. The Coast Guard
activated the final tower of the coastal phase of Rescue 21 Feb.
3, 2015, near the Pamlico Sound in North Carolina. Rescue
21 covers 41,871 miles of coastline along the entire Atlantic,
Pacific and Gulf coasts of the continental United States, as
well as along the shores of the Great Lakes, Hawaii, Puerto
Rico, the U.S. Virgin Islands, Guam and the Northern Mariana
Islands. With more than 250 communication towers, this portion of the system design and support is being accomplished
by General Dynamics C4 Systems, Scottsdale, Ariz.
The Coast Guard is in the process of implementing solutions for Alaska and along the western rivers targeted to
address the unique logistical and operational needs of those
regions. Because of Alaska’s vast area and limited connectivity
in remote locations, the Coast Guard is deploying a modified
Rescue 21 system tailored to factors such as population density, marine traffic, supportability, durability, accessibility,
weather and terrain. Likewise, the Coast Guard is completing
recapitalization of current communication systems at sites
along the Mississippi and Ohio River Valleys to meet the
unique needs of these busy inland waterways. These modified
systems, which will not include direction-finding capabilities
due to geographic and operational constraints, are scheduled
for completion by 2017.
CON TRAC TOR: . . . . . . . . . . General Dynamics
SEASPRAY 7500E MULTIMODE RADAR
BRIEFING: The 7500E multimode X-band radar is the primary
surveillance sensor of the HC-130H Hercules. It uses active
electronic scanned array technology to perform maritime
surveillance, detecting, tracking and classifying of maritime
traffic in support of all Coast Guard roles and missions, detect
and map spills of national significance, and support all-weather global operations. It fuses Automatic Identification
System-reported targets with SELEX radar targets for
improved maritime domain awareness.
CON TRAC TOR: . . . . . . . . . . SELEX Corp.
WWW.SEAPOWERMAGAZINE.ORG 148 SEAPOWER / ALMANAC 2017
COAST GUARD C4ISR SYSTEMS
U.S. Coast Guard Lt. William White, command duty officer for U.S. Coast Guard Sector Guam,
with the sector’s Rescue 21 communications system on June 9, 2016.