Commandant (G-TTM) U.S. Coast Guard 4 December 1995 Washington DC 20593 Why Digital Selective Calling Background. On February 1, 1992, changes to the Safety of Life at Sea (SOLAS) Convention affecting distress and safety telecommunications came into effect. The SOLAS Convention is a treaty document affecting cargo, passenger and other ships on international voyages. The SOLAS Convention has been both an international and national standard for maritime distress and safety telecommunications for all of the maritime community, including those vessels not specifically subject to the Convention. These changes require ships to carry VHF and MF/HF radios with digital selective calling capable of initiating radiotelephone calls. DSC is mandatory on board all ships of this type. This will allows them to discontinue watchkeeping on VHF channel 16 and on 2182 kHz on February 1, 1999 (SOLAS regulation IV/12.3 and .4, and 80.1123 and (d) of the Commission's rules). DSC also provides the opportunity for reducing or eliminating the congestion problem on VHF channel 16, alleviating hoax problems, more rapid receipt of a distress alert, and improved distress radio watchkeeping on VHF and MF/HF by Coast Guard stations. Further Reasons for DSC Requirement Our primary purpose for making this request is for reasons of safety, to ensure maritime distress and safety communications remain interoperable among all vessels, as discussed earlier. There are however additional reasons for granting this petition, all of which also involve maritime safety: DSC could reduce or eliminate the congestion problem on the VHF distress and calling channel 16. The Commission in PR Docket 91-167 (Notice of Proposed Rulemaking permitting VHF Marine Channel 9 to be used as a second calling channel), stated "the most common complaint received by the Commission related to marine radio usage concerns congestion on marine VHF channel 16." In a study of congestion, FCC staff stated "For a long term solution (to the problem of congestion on the distress, safety and calling channel 16), I recommend that the Commission consider a rulemaking to require Digital Selective Calling on all new marine radios and set a date when Digital Selective Calling would be mandatory for VHF marine radios."1. Alleviates hoax problem. Since DSC calls include a unique, preassigned and pre-entered ship identity, it would be difficult if not impossible to transmit a distress message without also identifying the vessel and its owner.2. ------------------------- 1. Mr. Vincent Kajinski, Engineer in Chief of the FCC Boston Regional Office, in his report of December 16, 1991 on Testing of VHF Maritime Channel 9 as a Secondary Calling Channel in Boston harbor. ------------------------- 2. During hearings on July 23, 1990 at Woods Hole, MA, by the U.S. House of Representatives Subcommittee on Coast Guard and Navigation, Committee on Merchant Marine and Fisheries, Mr. Richard M. Smith, Chief of the Commission's Field Operations Bureau, testified that "Our potential rulemaking solution, and one which I believe could have a great impact on this problem (of hoaxes), is a requirement for an automatic transmitter identification system or 'ATIS'. If adopted, it would eventually require radio transmitters to automatically send an unobtrusive identifying signal along with the normal signal. As one form of ATIS, the FCC and Coast Guard have been developing a digital selective calling (DSC) system for marine frequencies for use in the Global Maritime Distress & Safety System. If fully implemented in this decade as expected, DSC could perform effectively either to enable identification of hoaxers or help establish legitimate distress calls...The identifying code of the transmitter used in a hoax call would be an extremely powerful piece of evidence in identifying and prosecuting violators." ---------------------------- DSC provides rapid receipt of distress alert. DSC provides a preformatted distress alert which includes vessel identification, location and other vital information, which can be transmitted within a second or less. Vessel location can be obtained automatically from an existing LORAN C, GPS or other receiver, or entered manually. With this capability, vessel operators not having time to send a complete MAYDAY message over radio (e.g. in the case of the F/V SOL E MAR) could send a complete DSC distress alert. DSC significantly increases the probability that a call to the Coast Guard will be received. The FCC noted in their report on use of VHF Maritime Radio in Boston Harbor 1. that "It was quite common to observe 400 calls being made per hour on Channel 16 in Boston Harbor during prime time on weekends" and stated calls were more than double that on some occasions. The Coast Guard providers watchkeeping over channel 16 twenty four hours/day through the U.S. National Distress System, a network of over 300 transceivers with antennas located at high levels to ensure wide coverage, and remoted to one of 53 Coast Guard Group operations centers. One radio watchstander guards channel 16 from several of these sites simultaneously, listening for that one MAYDAY call to the Coast Guard among a constant background of dozens of simultaneous conversations. The Coast Guard responds to over 26,000 such distress calls each year. The continued growth in the amount of traffic on channel 16, in addition to the constantly increasing duties required of the Coast Guard Group watchstanders, makes their ability to acknowledge a distress call increasingly difficult. The same Coast Guard Group watchstanders who guard VHF channel 16 also guard the radiotelephone distress frequency 2182 kHz. Watchstanders at Coast Guard Communications Stations also guard several high frequency single sideband frequencies. These channels are noisy and difficult to guard, particularly if traffic on these channels are light. Resource limitations at Communication Stations as well as Groups require persons monitoring these frequencies to have other duties as wells. Consequently, the quality of watchkeeping on these channels is not high. Discussions with FCC field inspectors and those of the civil maritime community confirm this fact. However the Commission and Coast Guard require vessel carry radiotelephone equipment capable of using these frequencies for distress & safety purposes. Unless a solution is found to each of these problems, an increasing number of distress calls will go unanswered, an intolerable situation. Digital selective calling is capable of resolving these problems. DSC can ensure nearby ships capable of assisting a distressed vessel receive the distress alert. The current maritime distress system consisting of ship and shore watchkeeping on voice frequencies of 2182 kHz and VHF channel 16 ensured that ships in the vicinity of a vessel in distress could receive the distress alert. In many cases these nearby vessels can arrive on scene to assist the vessel in distress much more quickly than can the Coast Guard. Cellular telephones and satellite communications do not have this capability. We believe it to be essential that a ship-to-ship distress alerting capability continue to exist. DSC improves the ability of the Coast Guard to contact ships in an emergency. DSC will enable the Coast Guard, public coast stations or other shore units to contact ships concerning a marine warning or distress in their area, or for some other urgent matter, without requiring the ship operator to actively guard a radio channel. DSC technology is established in treaty and is recognized internationally. While other technology could conceivably be developed to resolve many of these same problems, both the International Telecommunications Union and International Maritime Organization, United nations organizations, selected DSC as the technology for this purpose after ten years of study. No other similar technology has this recognition. --------------------------------- This text was part of a petition for rulemaking and comments on a notice of inquiry submitted to the FCC by the Coast Guard regarding a proposal to mandate minimum DSC capability on marine radios (PR Docket 92-257)