Words: Andy Gent, CEO, Revector.
The UK’s search and rescue (SAR) organisations, that are heavily reliant on volunteers, aim to provide a highly responsive service despite having limited resources, finding missing people or retrieving those caught up in weather-related incidents. It is no surprise that search and rescue experts are turning to technologies that can help minimise risk and enable improved planning and smarter, more informed operations.
Recent data from Mountain Rescue England and Wales (MREW) indicates an upward demand for search and rescue services in the last five years. MREW reported a total of 2468 mountain rescue team deployments in 2020, compared with 1812 in 2016. Moreover, the MREW Annual Report for 2021 states there were 237,250 volunteer rescue hours last year, compared with 81,778 in 2016: almost a threefold increase.
Improving SAR effectiveness
In critical situations or for the seriously injured, the speed and effectiveness of SAR missions can make the difference to achieving a safe rescue. SAR teams are far more effective in daylight hours and any rescue that takes place at night-time may mean making a difficult choice between risking further human injury or leaving victims in the cold and dark overnight. This is far from straightforward in challenging or inaccessible terrain. In some circumstances, airborne technology, in the form of drones or Unmanned Aerial Vehicles (UAVs), can help save time and enable search operations to be more focused.
Already, the benefits of using drones for emergency services and medical purposes are widely acknowledged. They have undergone trials to deliver essential medical supplies to hospitals in Scotland, and the NHS has recently invested £28m in a trial of drones in southern England. Further afield, drones are being deployed in Africa to deliver medicines and vaccines to remote areas. In addition, the UK’s fire and rescue services are starting to use drone footage to inform decision making during large scale fires and road traffic collisions.
Drones to pinpoint rescue locations
Yet, drones can be used beyond this to lawfully gather intelligence that could save the lives of missing or injured people. SAR teams can use drones fitted with International Mobile Subscriber Identification catcher (IMSI) technology to fly over search areas to accurately pinpoint the locations of those in need of rescue, or survivors of natural disasters.
An IMSI is a 15-digit number assigned to the SIM card that identifies the mobile user within the network. Each IMSI is unique to a subscriber and is a way of identifying the owner. IMSI-catchers act like a traditional mobile phone network meaning nearby mobile phones connect to them. They can then pinpoint mobile phone locations and accurately identify where a mobile device is located.
Until recently, IMSI-catchers were solely associated with law enforcement agencies and the military for the purpose of covert surveillance, to gather intelligence, detect illegal activity and protect against security threats. Thanks to the miniaturisation of technology and a significant reduction in cost, IMSI-catchers are no longer confined to fixed positions, for use in-vehicle or by the roadside. Advances in components now mean that IMSI-catchers can be portable; compact and light enough to mount onto drones, and ideal for using over inaccessible landscape.
“Being able to identify the locations of those waiting for rescue makes it possible for emergency services to use drones to drop water, food and medical supplies to provide short term assistance.”
An IMSI-catcher can quickly identify any active mobile phone signal within a 20m radius or less, in any location. A drone can also search a large geographical area to locate people quickly, saving valuable time for search and rescue teams on the ground. Due to their association with surveillance, every country will have different legal parameters for IMSI-catcher use and this is an important consideration for SAR organisations both in the UK and abroad.
IMSI-catchers are fitted onto drones with a base station to detect mobile phone signals, so SAR teams can employ this technology to find signals even in areas without mobile network operator coverage. According to Ofcom, in January 2021 people cannot call or text from five percent of the UK’s remotest areas. Arguably, it is here that IMSI-catchers could become essential in SAR efforts.
Enabling more accurate SAR efforts
Take a scenario of a group of three walkers reported missing in the Cairngorm area of Scotland. In this case, SAR teams would be aware of the walkers’ identities and their approximate location. IMSI-catcher hardware fitted on a drone could be flown over the area ahead of a SAR team setting off, to identify the precise location of these walkers by verifying their mobile phone SIM numbers. This means that a SAR team could be dispatched knowing exactly where to find these people and achieving the rescue more quickly. Fewer resources would be needed for the search aspect of the operation, as there would be no need to send teams out to search a wider geographical area. Overall, there would be reduced risk to rescue teams and a swifter rescue for the stranded walkers; of particular importance in high-risk situations, in poor weather or when there are casualties involved.
In the event of a natural disaster, SAR teams may not be aware of individual identities but can use this technology to detect and track active mobile phone signals coming from the affected area. This could help identify victims and speed up their rescue; for example, by recovering people trapped by collapsed buildings in the aftermath of an earthquake or for rescuing those stranded by floods. If the mobile handset remains on, people can be identified even if they are unconscious.
Being able to identify the locations of those waiting for rescue makes it possible for emergency services to use drones to drop water, food and medical supplies to provide short term assistance.
Future support for SAR teams
The UK’s search and rescue organisations depend on highly trained individuals, but modern technologies can support these efforts. Being able to pinpoint the locations of those in need of rescue not only speeds up fast and safe recovery, but also protects search and rescue experts against spending unnecessary time in risky or dangerous situations.