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Note: This report was made to evaluate the utility of ground monitoring for supplemental ELT/EPIRB detection coupled with rapid local response. The system continues to be operational and useful today although the rate of incidents has fallen to about half of that recorded here.
Santa Barbara ELT Monitoring System Activity Summary July 1989-July 1998 Total Alarms: 315 121.5 ELTs/EPIRBs: 242 406 ELTs/EPIRBs: 17 Carriers: 56 Summary of ELT/EPIRB Alarms:
Actual Aviation Emergency: 7 Actual Marine Emergency: 3 Located on an Airport: 52 Located at a Harbor: 22 Located off Airport/Harbor: 16 Offshore (includes Moving): 25 Airborne Moving 77 Faded Out/Lost Signal 23 Other/Unknown Sources 35 Coverage area: Generally south of the Santa Ynez Mountain ridgeline from Gaviota to Ventura, seaward beyond the Channel Islands and (weather conditions permitting) southeast to Catalina Island.
Actual Aviation Emergencies 11/12/89: Airplane crash at Camarillo, 50 miles SE of Santa Barbara. 1 fatality. ELT instrumental in find. 12/29/89: Downed aircraft two miles north of Santa Barbara Airport. 3 survivors. Not an ELT find. 09/07/90: Aircraft crash west of Santa Barbara Airport. Throttle cable broke, aircraft flipped on landing. 2 on board, no injuries. Not an ELT find. 10/21/90: Aircraft crash east of Santa Barbara Airport. Low approach, caught gear on power lines, flipped into building. 4 on board, 1 fatality. Not an ELT find. 04/15/92: Aircraft crash at Santa Barbara Airport. No injuries. Not an ELT find. 05/05/92: Aircraft crash east of Camarillo Airport. 1 fatality. Not an ELT find. 10/15/99: Aircraft crash on west slope of ridge above Emma Wood State Park, Ventura County. 2 fatalities. ELT find by Ventura County Sheriff after alert from this system. Actual Marine Emergencies 05/27/90: Capsized vessel 18 miles offshore. 2 rescued.
07/05/92: Capsized trimaran south of San Miguel Island. 406 ELT/EPIRB Activations 11/30/90: EPIRB located at Santa Barbara Harbor; non-distress. 02/08/91: EPIRB, unknown location; went off abruptly. 05/15/91: Fishing boat went aground at Gaviota. Salvage operations knocked EPIRB overboard. 01/03/92: EPIRB located at Santa Barbara Harbor. Non-distress. 02/09/92: EPIRB located in surf below Shoreline Park from vessel that broke up in storm.
04/08/92: EPIRB located offshore; unknown final determination. 08/17/92: EPIRB located aboard Miss Jessica in Santa Barbara Harbor. Non-distress. 04/09/93: EPIRB located at Santa Barbara Harbor. Non-distress. 08/03/94: EPIRB located at Santa Barbara Harbor. Non-distress. 11/11/94: EPIRB located out of the area; unknown circumstances. 09/13/95: Unknown location; EPIRB went abruptly off the air. 04/04/96: Unknown location; EPIRB went abruptly off the air. 08/21/96: Unknown location; EPIRB went abruptly off the air. 10/28/96: Unknown location; EPIRB went abruptly off the air. 02/05/97: EPIRB located at Santa Barbara Harbor. Non-distress 04/17/97: EPIRB, probably on a moving vessel in the area of Point Conception. Santa Barbara South County ELT/EPIRB Alerting System The Santa Barbara System Concept It is well known that the satellite system for ELT and EPIRB reporting suffers overloads at times from the large numbers of false and interfering signals. Non-distress signals can be as high as 97% on 121.5 and 243 MHz and 87% on the newer 406.025 frequency. Because at least two orbital passes are needed for ground location and the need to reduce the clutter of false signals, response to a real emergency may be delayed for up to 8 hours or even be missed completely. L-Tronics, a manufacturer of direction finding equipment, asked: Could a local ELT monitoring network provide faster response to actual emergencies AND rapid shut-down of false alarms? Could this reduce the number of "hits’ on the satellites, thus diminishing the workload on the Rescue Coordination Centers?The company developed a monitoring receiver that used a unique frequency-comparison squelch circuit. It listens for any continuous signal on 121.5 MHz (including a carrier signal such as a broken ELT/EPIRB or stuck microphone). A delay time of 10 minutes from the time the signal is first heard until the monitor activates alerting tones prevents activation on tests and conversations.
System Design When the Santa Barbara Monitoring System first went into service in July 1989, there were five monitoring sites: One at each of the L-Tronics ® partner locations (Magnolia Shopping Center area and Cathedral Oaks/Kellogg area), one at the California Mountain Company building (where a number of Los Padres SAR team members worked) near the Santa Barbara Airport, and one at the Santa Barbara Amateur Radio Club (SBARC) repeater site on La Vigia Hill, overlooking Santa Barbara Harbor. The SBARC receiver puts out a paging tone on an amateur frequency to alert responders. A fifth monitor was installed at the Civil Air Patrol (CAP) repeater site on Santa Ynez Peak (4300 ft) for high-level coverage of the South Santa Barbara area.Direction finding capability is available at the two L-Tronics ® sites, while both repeater systems could be interrogated to give a few seconds of the audio they are receiving. This allows mission managers to determine if a beacon was still operating and to listen for signal characteristics that might indicate a moving target.On the second day of operation the system alerted to an EPIRB floating in the ocean 22 miles off the coast of Santa Barbara. Over the course of nine years, the system has been modified somewhat. The CMC site has been replaced by a new monitor installed on an amateur repeater on the UCSB Library building overlooking the airport. It can also be interrogated for a short audio sample of the signal. Two additional monitor stations, one at LaCumbre Peak (3900 ft) and one on Santa Cruz island (2700ft) 25 miles offshore were completed in 2000.
The SAR Response The County Sheriff has responsibility for search and rescue in his county. The Santa Barbara County Search and Rescue Team is assigned the response. It soon became apparent that the system was alerting to many signals that were quickly determined to be moving or otherwise a non-response condition. System operators were able to develop some discrimination techniques. They were eventually able to tell the difference between a stationary ELT or EPIRB and one moving on the ground, on the water or in the air. Today, the SBCSAR operations leader can quickly downgrade the response based on information received from the ELT monitoring system and operators, the Federal Aviation Agency, Air Force RCC, US Coast Guard, and harbormaster. If initial information from the monitoring system indicates any possibility of a distress situation, or lacks positive data that the alarm is false, a full team response is made. If initial information indicates a marine EPIRB that is not in the harbor or nearby land area, the US Coast Guard Rescue Coordination Center is notified and briefed and is updated as information becomes available from the system.
Summary The Monitoring System in Santa Barbara has met the challenges set for it, providing prompt notification of an ELT/EPIRB activation, resulting in rapid deployment of SAR forces and quick shut-down of non-distress signals.In the nine years since the system was installed, there have been only three instances where SAR forces were alerted by the Air Force RCC of an ELT/EPIRB activation in the area compared to 21 in the same area in just one year before the system was installed. This proves that rapid shut-down of false alarms prevents the SARSAT system from hearing them and the RCC from having to process them. Identification of a marine situation allows the Coast Guard to immediately activate its forces without the loss of time for the SARSAT to process the emergency signals.
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