UAV’s in Ultra Long Range SAR missions

Each week, Ben Drew-Head of Conference Programmes at Tangent Link takes a look at a session from the International Search & Rescue Conference  offering his personal viewpoint on current issues and potential solutions, on which we encourage the wider industry to comment.

In this post, Ben addresses the subject of Unmanned Air Vehicles (UAV) and the growing interest in their use in SAR, particularly, when deployed in long-range search missions in remote regions where vast areas of ocean can tax a manned maritime patrol aircraft.

UAVs in Ultra Long Range SAR (Search & Rescue) missions

Search & Rescue is a misnomer when relating it to an UAV-Unmanned Aerial Vehicle as, in reality, it can currently only perform the Search role…and not the Rescue or Recovery – yet.  So really its SAR mission should be described as Search & Locate, to be exact.  Unless, of course, one day they drone an amphibious aircraft which could also pick up disaster survivors or, at least deliver liferafts, water and medical packs, but this only makes the mind boggle.

In short-to-medium range SAR missions, UAVs are a SAR multiplier and enabler by replacing the SAR helicopter pilot and crew who, according to the US Coastguard, spend 99% of their mission in search mode and 1% in Rescue and/or Recovery mode.    In the case of helicopter SAR, the search mission can be very fatiguing – long hours of concentrating on MFDs in bad weather, or NVG flying, or crew scanning the sea surface with binoculars – which, when the disaster site is located, can affect the rescue mission performance.  By deploying a UAV first the pilots and crew are completely fresh to perform the rescue mission.   The UAV can also benefit the fixed wing SAR pilot as well by apportioning the more hazardous or difficult parts of the mission to a drone, enabling the pilot to cover his particular search area more effectively.

With the reduction in Middle East conflict commitments UAV manufacturers are now initiating their own search for new commercial customers.  As their UAV technologies continue to improve, so does the likelihood that unmanned systems will prove instrumental in locating downed aircraft, sinking ships and capsized yachts in Ultra Long Range Search and Rescue in remote parts of the world’s oceans.

Long range SAR is currently performed using fixed wing maritime patrol aircraft and satellites. With UAV flying times increasing exponentially and fuel efficiency also improving – particularly with hydrogen-powered systems – the UAV becomes even more attractive as a SAR asset.

Deployed in numbers UAVs can scan vast tracts of sea for missing aircraft or vessels.  When UAVs are swarmed – where multiple UAV systems are programmed and deployed in different search patterns and staggered formations – they can also potentially save precious search time, costly manned aircraft fuel, and a potential loss of crew should rescue efforts prove disastrous due to poor weather conditions or aircraft malfunction.

New morphing technologies emerging from industry will also permit UAVs to fly in all-weather conditions by adjusting their shape while in flight thereby allowing them to perform flight controls without the use of conventional control surfaces. This technology promises the advantages of being able to fly multiple missions types in all weathers and be more fuel efficient.

Scanning capability over water is also allowing easier and more accurate target identification against the ocean’s ever-changing surface.  Fitted with high-resolution cameras, IR & Thermal Imaging, datalinks and other sensors UAVs can cover vast tracts of ocean and, should they come upon mariners in distress, mark the location and relay real-time video information to coastguard vessels or command-and-control aircraft in the area.  Coast Guard ships and helicopters capable of carrying rescue swimmers or delivering life-saving equipment can be vectored to the disaster scene more efficiently.

But in the Southern Hemisphere this can be a daunting prospect considering 80% of the area is covered by water.  Both the Air France AF-447 & Malaysian Airlines MH-370 crashes occurred in this region.

There are some extraordinarily capable UAVs which fit the Ultra Long Range SAR role waiting patiently in the wings for a requirement from a single or group of nations who see their cost vs operational benefits.   All of them need runways to deploy at the moment.

Northrop Grumman’s long-range Global Hawk drones can stay aloft for 30 hours and fly 11,000 miles (17,700 kilometers) with their 116-foot (35-meter) wingspans. It can reach and remain on station over a disaster area performing valuable surveillance even when the weather is a shocker.  But at $35 million per unit it’s not for the faint-hearted.

General Atomics Predator has a wingspan of 55 feet, endurance of 40 hrs and ceiling of 25,000 ft and a $4 million price tag. Its military derivatives, Predator B and the Reaper fly twice as fast and high but endurance is reduced to 30 hours.

AV’s Global Observer is 70 feet long with a 175-foot wingspan and clearly has maritime applications as it can cover large expanses of ocean. Being hydrogen-fuelled this HALE (High Altitude Long Endurance) unmanned aircraft system can fly for up to a week and loiter over the target and carry a payload up to 400 pounds. It is capable of flying at 60,000 feet and its sensors can deliver a surveillance footprint 600 miles in diameter. The sensors include two cameras with current view and infrared and can stream back live wireless to support SAR Command & Control.

UAVs will, one day, be a significant Search & Rescue asset and a force multiplier to the satellite and long-range maritime patrol piloted aircraft.   Finding disaster sites doesn’t necessarily mean rescuers will reach them in time to save the afflicted, but locating them early enough in the search cycle will give those survivors just a bit more chance of surviving the ordeal.

Ben Drew
Head of Programmes
Tangent Link