Notice to mariners: U.S. Coast Guard launches long-delayed communications system.

Author:Kennedy, Harold

CHINCOTEAGUE, Va. -- The Coast Guard's delayed and expensive search-and-rescue communications network has made its debut here and at an air station in Atlantic City, N.J.

Rescue 21, as the system is known, is intended to make dramatic improvements in the Coast Guard's ability to locate and assist boaters in trouble, while maintaining full operability with federal, state and local law enforcement agencies and emergency first responders, explained Capt. Dan Abel, system project manager.

The service is introducing the system gradually throughout the nation, Abel told National Defense. When the network is complete--now scheduled for 2011--it will be employed along 95,000 miles of U.S, coastlines, navigable rivers and waterways, including Alaska, Hawaii, Guam and U.S. possessions in the Caribbean.

"Ninety percent of the coastline will be covered," Abel said.

Rescue 21 is replacing the aging national distress and response system, which was built in the 1970s and includes radios, transceivers, antenna towers and an interconnecting network.

Rescue 21 represents a quantum leap in technology over that setup, Abel said. "The idea is to take the 'search' out of search and rescue."

The backbone of the current system is the very high frequency-frequency modulation short-range communications network, more commonly known as VHF-FM. The Navy's Space and Naval Warfare Command, however, has found 88 gaps, or "dead zones," along the U.S. coastlines where existing signals don't reach, Abel said.

Rescue 21, he added, will eliminate those gaps and ensure continuous, enhanced VHF-FM line-of-sight marine-radio coverage out to 20 nautical miles from shore. Higher-powered radios may be heard even farther offshore. Abel cited these additional benefits:

A digital voice-recording capability provides immediate playback, improving the ability to review and decipher garbled or unclear transmissions. "That's critical in search and rescue planning and response," he said.

An improved direction-finding technology--able to locate boaters within two compass degrees--cuts the time that search-and-rescue crews need to respond to calls for help, Abel noted.

The number of voice and data channels is increased from one to six, allowing watch standers to conduct multiple law-enforcement or homeland-security operations, and to use protected communications lines when necessary.

A new marine radiotelephone service, called digital selective calling, will allow mariners with the proper...

To continue reading