Search and Rescue (SAR)
For over 40 years, NASA’s Search and Rescue office has aided the international Cospas-Sarsat Program in the development of search and rescue technologies. Cospas-Sarsat is a cooperative effort of 44 member countries and organizations dedicated to providing robust and reliable satellite-aided distress location services worldwide. The Search and Rescue office has been integral to designing and testing Cospas-Sarsat’s 406 MHz distress beacons, as well as the flight and ground systems that support them.
When beacon users find themselves in distress, they can activate their beacons that will begin the search and rescue process. Global Navigation Satellite System constellations like GPS and Galileo host Cospas-Sarsat’s primary flight segment, which listens for beacon signals. Those signals are relayed to ground stations — known as local user terminals — which use the data to calculate the beacons’ locations. The system supplies that data and the computed location to relevant organizations and first responders across the globe.
In the United States, search and rescue efforts are coordinated through the national search and rescue program called SARSAT. This is a combined effort between NASA and three other U.S. agencies. The Air Force coordinates inland search and rescue, the Coast Guard coordinates maritime search and rescue, and the National Oceanic and Atmospheric Administration operates the system. NASA infuses technology into the overall program to minimize the search time and maximize the rescues.
In their lab at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, the Search and Rescue office develops, tests, and troubleshoots both space-based and ground-based search and rescue technology. They also investigate new ideas and innovations that could enhance search and rescue operations. Some of these cutting-edge efforts include:
- New search-and-rescue repeaters for use on Global Navigation Satellite Systems like GPS. These repeaters significantly reduce the time it takes to locate distress signals.
- Second-generation beacons for use by pilots, mariners, and adventurers of all stripes across the globe. These offer a host of improvements to existing beacon technologies, including improved accuracy, quicker response times, and a more robust signal. Second-generation technologies will be passed to commercial industry for manufacture and sale after acceptance by the international Cospas-Sarsat Program.
- Phased-array search and rescue ground station antennas that can track more than 20 spacecraft at once, enhancing capabilities and reducing costs.
- Unmanned Aircraft Systems (UAS) that can track beacon signals. This innovation will improve the response times of search and rescue professionals, especially in remote areas like the forests or the open ocean.
The Search and Rescue office actively works to make air travel safer by studying the performance of emergency locator transmitters (ELTs) that are specially designed beacons for aircraft. The beacons will activate automatically in the event of a crash. Their comprehensive study of ELT failures helped develop recommendations for the Federal Aviation Administration, emergency beacon manufacturers, and airframe manufacturers regarding beacon installation and survivability.
The office is also utilizing its second-generation beacon technology to develop specifications for a new global, real-time aviation distress-tracking system. This system will use the Cospas-Sarsat network to leave breadcrumbs along a plane’s route well before crash-related activation, providing supplemental location data that improves the accuracy of the system and response times.
Search and Rescue professionals monitor NASA Commercial Crew Program missions to the International Space Station. The SpaceX Crew Dragon and Boeing CST-100 Starliner vehicles are both equipped with SAR-developed emergency beacons. These beacons help NASA locate astronauts in the unlikely event of a launch abort scenario or during splashdown upon return from the station.
In addition to Commercial Crew Program missions, the Search and Rescue office also monitors beacon-equipped Russian Soyuz vehicles transporting astronauts to the orbiting laboratory from the Baikonur Cosmodrome in Kazakhstan.
The first users of the Search and Rescue office’s new second-generation beacon technologies will be Artemis astronauts returning from the Moon. These miniaturized Advanced Next -Generation Emergency Locator (ANGEL) beacons will be attached to astronauts’ life preserver units. When astronauts splash back down to Earth — or in the unlikely event of a launch abort scenario — these beacons will allow them to be found if they need to egress from the Orion capsule.
In addition, the office is developing exploration capabilities as part of NASA’s Lunar Search and Rescue (LunaSAR) concept, extending the best practices of current Earth-based SAR systems to the lunar surface. LunaSAR ties into NASA’s LunaNet concept, a flexible and extensible lunar communications and navigation architecture.
LunaSAR will extend ANGEL beacon usability from Earth to the lunar surface, enabling rapid response to potential distress situations on the Moon. LunaSAR will use LunaNet and other cislunar comm and nav architectures as a backbone for transmitting rescue data during lunar surface activities.