CSAR: Building towards capability

Lockheed Martin/Sikorsky's new HH-60W will be used by the US Air Force for combat rescue and other special missions.

Dr. Joetey Attariwala – Combat Search and Rescue (CSAR) as a joint force operation requires a specialisation that many nations cannot afford. However, mission equipment and specialised aircraft can provide a workable capability when required.

Combat Search and Rescue (CSAR) is a highly specialised mission capability which is distinct from traditional Search and Rescue (SAR). Most nations invest in multi-level SAR which is often integrated with Coast Guards and paramilitary organisations like law enforcement and fire/rescue agencies. CSAR differs in the specialist nature of the mission which is focused on the recovery of distressed or isolated military personnel in a wide range of threat environments. The very nature of CSAR means that missions often exist in non-linear, non-contiguous battlespace.

It was in April 1944 that the world’s first helicopter combat rescue was conducted by the US Army Air Forces’ 1st Air Commandos in Burma with a Sikorsky R-4 helicopter. The CSAR mission became much more well known during the Vietnam War, and more recently during the wars in Iraq and Afghanistan.

Technically speaking, CSAR can encompass multiple modalities of rescue – be it land, sea or air – however it is commonly acknowledged that CSAR usually references airborne assets including fixed wing aircraft (variants of the Lockheed Martin HC-130 for example), and rotary wing assets which are the most prevalent for this role, principally due to their ability to extract personnel by landing or by hoist. This article will principally focus on CSAR helicopters crewed by highly trained pilots, gunners and pararescuemen (PJs).

Today’s CSAR aircraft are configured for day and night operations, and often operate independently, which means they are fitted with very sophisticated equipment. Pilots in modern CSAR helicopters regularly use Night Vision Goggles (NVG); while aircraft can be fitted with radars such as the multi-panel Leonardo Osprey, a small size, weight and power (SWaP) AESA radar system (E-scan) which provides a genuine multi-domain 360 degree coverage capability. According to Leonardo, being a lightweight, flat panel radar with no moving parts makes it ideal to attach to the side of an aircraft and integrate with whatever type of mission system is being used. It also uses a tactical long-range Ground Moving Target Indicator (GMTI) which allows the helicopter crew to examine the target area prior to beginning the insertion of a rescue team or pick-up of personnel.

Leonardo’s Osprey AESA radar uses lightweight flat panels with no moving parts.

CSAR necessitates the acquisition of aircraft with dedicated mission equipment and systems, coupled with an operational capability that requires constant training. Coordination of CSAR missions involves substantial command and control and support assets. All of this means that CSAR is a very expensive capability which is often out of reach for many nations.

No standardisation

It is largely understood that Asia-Pacific countries have a hodgepodge of CSAR capability or aspirations for such. It is also true that most of the countries in the region act independently, which means there is no standardisation of capability. As a result, most countries in the region try to adapt existing aircraft to fill the CSAR role as required. India for example, with its large Air Force, has no dedicated CSAR capability, but it does use the Russian Helicopters Mi-17 in this role as needed.

South Korea operates the Kamov Ka-27 in the CSAR role, and the Boeing CH-47 and Sikorsky S-70 as multi-role aircraft, including the capacity to conduct CSAR. Taiwan, Thailand and Indonesia operate the Airbus Helicopters EC225, EC725 and H225M respectively in the CSAR role.

The largest CSAR capacity in the Asia Pacific region is fielded by the United States military. The US Air Force Air Combat Command (ACC) has overall responsibility for CSAR in the USAF – active duty, Reserve, and Air National Guard units provide CSAR for all US military services and allies as required. Units like the 31st and 33rd Rescue Squadrons assigned to the 18th Wing at Kadena Air Base in Japan, and other USAF CSAR units based in Alaska stand ready 24/7 to execute on CSAR missions with the majority of these assets comprising Sikorsky HH-60G Pave Hawk helicopters.

Similarly, the US Navy uses MH-60S Seahawk helicopters for CSAR. These CSAR units often train throughout the region including major exercises like Exercise Angel Reign, a bilateral joint personnel recovery exercise between Australia and the United States.

Speaking about CSAR in the region, Christophe Nurit, Sikorsky regional executive for Asia said: “When it comes to CSAR, discerning customers in the Indo Pacific region understand the value provided by Sikorsky helicopters,” said Nurit. “The saline, hot and humid environment throughout the region can generate corrosion, which can be the cause of many technical issues. Sikorsky’s experience with H-60 Seahawk helicopter’s anti-corrosion coating and manufacturing has proven a great benefit for the Black Hawk. With a few exceptions, where Sikorsky had to develop new operating and rinsing procedures, Sikorsky products have a strong reputation of handling the Asia-Pacific environment extremely well.”

The core of CSAR

A CSAR mission deals with the coordination, support and implementation of the extraction of injured or stranded personnel in a hostile area or active combat zone. The most common helicopter types utilised in the CSAR role today are the Sikorsky UH-60 / S-70i Black Hawk or variants thereof; Airbus Helicopters EC725 / H225M; and Leonardo Helicopters AW101.

The mission requires the location and extraction of distressed personnel as quickly as possible, regardless of time of day, illumination, or weather conditions. It is for these reasons that CSAR helicopters are heavily modified with sensors, aids, and weapons. These include the following in any combination thereof: electro-optical infrared (EO/IR) pods, weather radar, search radar, IFF, radar warning receiver, missile warning receiver, laser warning receiver, personnel locator systems, tactical radios, rescue hoists, night-sun, loud speaker, Infrared Countermeasures (IRCM) systems, Directional Infrared Countermeasures Systems (DIRCM), and chaff and flare dispensers. Naturally, these sensors and systems all act in concert to effectively carry out complex CSAR missions.

Another special characteristic of some CSAR helicopters is air-to-air refuelling probes which are more common on all HH-60 Pave Hawks, and on some H225Ms, and AW101s like the Italian Air Force HH-101A ‘Caesar’.

“Air refuelling probes extend our range out to the endurance of the crew. We validate that tactic through civilian search and rescue as well, where we’ve flown missions in excess of 1,000 miles out to sea. We also have external fuel tanks to help with range,” said Major Christopher O’Branovich, HH-60 Functional Air Manager, HQ ACC Personnel Recovery Branch – USAF. “We’re also armed so we’ll fly with .50 caliber GAU-18 weapons; and we can also use the GAU-2 minigun. We also have a number of defensive systems to help protect us in a combat environment. We have an array of rescue extraction equipment – we fly with para-rescue personnel so whether it’s a jungle environment, or a water environment, anything really – we have fast ropes to quickly infill a team to a survivor. We also have advanced navigation equipment to help us navigate in contested areas.”

Lieutenant Colonel Adam Harris, HC-130 Training Manager for HQ ACC – UASF, added: “CSAR technology is always evolving so you have to consider sensors and how they’ll work together. One of the things we thought from the very beginning was how the HC-130 and HH-60 would integrate together. That’s something you would expect any search and rescue force to be thinking about and looking at… From a training perspective, Air Force CSAR is part of every Red Flag that we have at Nellis; we also have a dedicated Red Flag Rescue exercise which is run at Davis Monthan Air Force Base – it’s a CSAR specific exercise.”

In many cases good location intelligence for the target is unavailable, so the aircraft may be required to execute a search pattern. EO/IR sensors are critical for this task, and therefore require maximum target detection, recognition, and identification (DRI) range performance under a variety of illumination conditions from full daylight to dusk/overcast, to full darkness. Longer target detection range means larger search pattern coverage, and longer target recognition and identification range means fewer deviations from the search grid. This results in a shorter, more effective mission that minimises the exposure of both the target and the CSAR crew to hostile action.

The optimum EO/IR sensor for CSAR missions includes both wide angle optics to maintain situational awareness and for target detection, and narrow angle optics for target recognition and identification range performance. A low light sensor maintains range performance as light levels start to drop off – under dusk or overcast conditions for example. A thermal imaging sensor requires no light, relying instead on heat radiated by the target. As such it’s useful in full dark night conditions. Cooled mid-wave IR cameras are the current standard in thermal imaging as they provide better sensitivity and resolution than long-wave IR.

Laser pointers generally operate in the near IR band, and are used to mark targets or coordination points for ground personnel wearing night vision goggles. Conversely, the low light camera is sensitive in both the visible and near infrared bands. As such, it can image both the spot projected by the laser pointer, as well as a covert personnel beacon that may be worn by downed personnel.

Short wave infrared (SWIR) imagers have become more available in the last 5-10 years, and they offer a couple of distinct benefits to CSAR missions. The first is enhanced smoke penetration in the EO band, versus visible or near IR bands, which can be an issue in an active combat zone. They are also able to ‘see’ personnel beacons that operate in the SWIR band. NVGs have become ubiquitous in combat zones, so the operating band of choice for covert beacons is changing to SWIR.

L3 WESCAM’s MX family of EO/IR sensors satisfy all of these requirements with image stabilisation and DRI range performance in each sensor size class. The MX-15 has traditionally hit a ‘sweet spot’ in the market in the trade-off between performance versus size/weight in the rotorcraft market, while the newer MX-10 has set a new standard for imaging performance in a small sensor

FLIR Systems is another key manufacturer of EO/IR systems found on CSAR aircraft. According to FLIR, their most suitable product is the Star SAFIRE 380-HLDc which benefits the CSAR aircraft by providing a lightweight, multi-spectral, system with an integrated laser boresighting system for the laser designator. Payloads include options for SWIR, EO, EMCCD, and of course an MWIR thermal imager. This is a single line-replaceable unit (LRU) system at much less the cost and weight of full size systems such as the Star SAFIRE 380-HLD, but with the same laser performance and the required range capability for the CSAR mission. FLIR utilises a vertical integration approach, manufacturing the lasers (even growing the laser crystals), the lenses, and the thermal imaging sensors. This ensures the greatest range, clearest image, and maximum laser energy on target.

Onboard weapons

Crew-served weapons – machine guns and miniguns – are the primary defensive armament on CSAR aircraft. These weapons are primarily used for cover fire and self-defence. Countless manufacturers produce guns that are suitable for helicopter mounted air-to-ground gunnery, however some companies stand out, like Dillon Aero which produces the M134 7.62mm family of miniguns.

AMR has learned that Dillon Aero will soon introduce its new 3-barrel .50 calibre 503D gatling gun which could be used for CSAR. “This is the first time that Dillon has designed a gun from the ground up. It’s a completely new design,” said Rob Rainier, international business development manager for Dillon Aero. “The new 503D will be complementary to our minigun, and will be a direct competitor to the .50 calibre GAU-19. We expect testing to be complete by early summer, at which point we’ll go into full production.”

Belgium’s FN Herstal manufactures two key weapons suitable for the CSAR role: the 12.7mm FN M3M/ GAU-21A/B machine gun and the 7.62mm FN MAG 58M/ M240 machine gun.

France’s Nexter offers the SH20 which is a retractable mount system for the firm’s 20mm M621 cannon. The SH20 was developed to support the French special forces, and can outfit new or retrofitted helicopters.

Operating any of these weapons depends on the mission at hand and aircraft weight considerations. For night operations, door gunners use night vision goggles with gun-mounted lasers for more accurate aiming.

Indonesia H225Ms for CSAR

The Indonesian Air Force announced in early January that it has ordered eight additional twin-engine multirole H225M helicopters as part of the country’s fleet-strengthening initiative for a CSAR-capable fleet. According to Airbus, Indonesia’s existing fleet of six H225M’s has flown over 2,000 flight hours to-date; operationally deploying for missions including CSAR, tactical transport and humanitarian operations. 

Indonesia has ordered a further eight multirole H225Ms for its missions including CSAR.

Under the agreement between the Indonesian Ministry of Defence and PTDI, the 11-ton H225M helicopters will be delivered to the Air Force upon reassembly and completion of mission equipment outfitting and customisation by PTDI at its facility in Bandung, Indonesia.

“We welcome Indonesia’s selection of our H225M helicopters for their expanding fleet. The H225M is a combat-proven helicopter that is well regarded by military customers worldwide, and Indonesia’s additional order speaks strongly of their confidence in Airbus’ helicopters,” said Ben Bridge, executive vice president, Global Business of Airbus Helicopters.


As part of the Combat Rescue Helicopter (CRH) programme, the USAF selected Sikorsky to provide a replacement platform for the USAF HH-60G Pave Hawk helicopters. The programme of record calls for 112 CRH HH-60W helicopters to replace the aged Pave Hawk helicopters.

The new HH-60W ‘Whiskey’ adds capability advancements to better support the full range of combat rescue and other special missions. Designed to meet long-range and high threat requirements for the USAF, the Whiskey will expand upon the UH-60M Black Hawk’s versatility by nearly doubling the internal fuel capacity without the use of space-hungry auxiliary fuel tanks; providing a robust weapons suite; and integrating defensive systems and sensors to provide an unprecedented combination of range and survivability.

The helicopter will have an all new Tactical Mission Kit; the integration of which provides sensors, radar, and survivability-enhancing defensive/communication systems that add seamlessly blended geo-situational awareness displays into the aircraft, giving crews more information to make decisions during mission execution.

“We expect the aircraft to begin flight testing later this year, and that should typically last one and a half years before we start delivering aircraft out to the units,” said Major Vincent Powell, Rotary Wing Branch Chief ACC HQ – USAF.

by Dr. Joetey Attariwala