Much has been written about the ubiquitous nature of the modern maritime multirole helicopters (MRH) currently patrolling the skies above the world’s oceans. The capability of the helicopter to operate from a ship deck, hover for long periods of time and fly the nape of the earth/sea to avoid radar detection; make them invaluable for maritime role. Since the employment of maritime rotorcraft during World War II, Flettner Fl 282s were used by Germany for reconnaissance, and Sikorsky R-4s were used by the United States. The most obvious roles were reconnaissance, search and rescue (SAR), and medical evacuation. The other roles were anti-submarine warfare (ASW) and electronic warfare. ASW employs air, surface or subsurface platforms to detect and damage/destroy enemy submarines. Like other types of warfare, ASW also requires sensors to locate the submarine and weapons to destroy it. The sensors are generally based on sonar and armament usually used is the torpedoe. Both the sensors and the weapons can be employed from air, surface and subsurface platforms. Aerial platforms are the most mobile, flexible and cost-effective. Even in today’s age of networked sensors, extensive use of satellite resources and high-altitude long-endurance unmanned aerial systems such as the US Navy’s broad area maritime surveillance system based on navalised Global Hawk; the fact remains that the notion of the embarked helicopter as the fleet’s “eyes and ears beyond the horizon” is more relevant today than at any time in our history.

Why?

Two primary reasons immediately advance to the fore. An ever increasing reliability of the aircraft and an ever increasing missionsystem-integrated sensor suite are the two largest drivers. The advances in these two areas can be simply illustrated comparing the relative reliability and mission system capabilities of the Westland Wasp and the MH-60R Sea Hawk. In between there are other examples like the Kamov series of Russia, Sikorsky SH-60/MH-60 series of the US and many more.

The Wasp was a navalised Scout helicopter and inducted into the Royal Navy during 1962. It was arguably one of the best among the earliest forms of reliable multi-mission maritime helicopters. It delivered two crucial capabilities never before available to the fleet: eyes beyond the horizon for the ship’s sensors and a capability to deliver an antisubmarine warfare (ASW) weapon beyond the engagement range of the submarinelaunched anti-ship torpedo of the day. It came into limelight during the Falkland War when on April 25, 1982, the Argentinian submarine ARA Santa Fe was spotted by a Wessex helicopter from HMS Antrim. The Wessex and a Westland Lynx HAS.2 from HMS Brilliant then attacked it. A Wasp launched from HMS Plymouth and two Wasps launched from HMS Endurance also fired AS.12 antiship missiles at the submarine, scoring hits. Santa Fe was damaged badly enough to prevent it from submerging. The last Wasp was finally withdrawn from service in 1988.

The Russian Kamov Ka-27 helicopter was developed for the Russian Navy to carry out ASW and ferry troops. Like other Kamov military helicopters, it has a rotor, removing the need for a tail rotor. It is in service in many countries including Russia, China and India. It also carries radar, magnetic anomaly detection system or a dipping sonar. Kamov Ka-28 helicopter is designed to search, detect, track, and engage surfaced and submerged submarines. The later version, Ka-28, is capable of undertaking longendurance ASW missions with no reference waypoints, in all-weather conditions, at a range of over 200 km, at a sea state of up to five. The helicopter can be configured to operate in search, search/attack, or attack variants. The helicopter’s avionics suite includes an integrated flight navigation system and a sighting system which provides all-weather navigation, submarine detection, weapons control, return flight to the mother ship and landing approach.

Sea Hawk series is a multi-mission US Navy (USN) helicopter based on the US Army UH-60 Black Hawk and a member of the Sikorsky S-70 family. The USN uses the H-60 airframe under the model designations, SH-60B, SH-60F, HH-60H, MH-60R and MH-60S, which can be deployed aboard any air-capable ship. The Sea Hawk can be employed for ASW, anti-surface warfare, naval special warfare insertion, SAR, combat search and rescue (CSAR), vertical replenishment and medical evacuation. All Navy H-60s carry a rescue hoist for SAR/CSAR missions.

Virtually as soon as these were employed, the operators of these aircraft and the fleets they served found several new challenges—when one is able to “see” beyond the horizon, one must be able to efficiently manage the contacts detected and classified by the air crew. Thus began the ever increasing demands on air/ship data management and target tracking—a task made all the more difficult with continual introduction of ever more sophisticated sensor systems such as the radar, EO/IR, passive and active acoustics and electronic support measures.

There have been several fleet and ship-capability enhancement studies undertaken over the decades which have concluded that to improve the ships warfighting capability, one of the key aspects is to improve the capability of the MRH. Nowhere is this more evident than in the current state-of-the-art maritime strike helicopter (MH-60R).

The penultimate multi-mission maritime strike helicopter of today takes the huge integration challenges of these varied sensors head on with a highly automated aircraft/ship crew coordination choreographed through a high-speed, broadband data link in addition to secure voice communication. The fielding of this most formidable weapon system drew high praise from the very first deployment with the naval aviators terming the MH-60R—“Romeo” a “game changer”. MH-60R is equipped for multiple roles including ASW, anti-surface warfare, SAR, naval gunfire support, surveillance, communications relay, logistics support, personnel transfer and vertical replenishment. For ASW missions, the helicopter is equipped with a sonobuoy launcher and a Raytheon AN/AQS-22 advanced airborne low-frequency dipping sonar; Raytheon AN/AAS-44 detecting/tracking system, which includes forward-looking infrared and laser rangefinder; radar is the Telephonics AN/APS-147 multi-mode radar which has inverse synthetic aperture imaging and periscope, and small target detection capability. Lockheed Martin has been awarded a contract to develop a new radar system, the automatic radar periscope detection and discrimination system, to be delivered from 2013. For countermeasures, it is fitted with Lockheed Martin’s AN/ALQ-210 electronic support measures system. Electronic warfare systems include the ATK AN/AAR-47 missile warner, laser warning system, BAE Systems’ AN/ALQ-144 infrared jammer; BAE Systems’ AN/ALE-39 chaff and flare decoy dispenser. The MH-60R helicopter shares the same MH-60 multi-function digital glass cockpit as the MH-60S helicopter. For ASW, the MH-60R can carry up to three ATK mk50 or mk46 active/passive lightweight torpedoes. A pintle-mounted 7.62mm machine gun is fitted for self-defence. With full rate production approved in 2006, the USN expects to operate 252 MH-60R helicopters by 2015. Lockheed Martin provides the digital cockpit common to the MH-60R and MH-60S helicopters, while Sikorsky manufactures the airframe.