Tag Archives: Helicopter

Kaman SH-2F Seasprite

United States of America (1974)

Anti-Submarine & Utility Helicopter

190 total airframes built: 85 converted to SH-2F w/ 48 new airframes.

A SeaSprite takes on fuel aboard the Destroyer USS Briscoe. (National Archives)

Introduction

Kaman’s SH-2 proved an exceptional asset for the US Navy through the mid to late Cold War, serving a variety of roles across nearly the entirety of the surface fleet. Beginning its service as a multipurpose naval helicopter designed to ferry equipment and rescue downed fliers, the light helicopter soon played an even greater role as an anti-submarine aircraft. Replacing the outdated and clumsy DASH drone, the Seasprite incorporated cutting edge sensors to become a sub chaser that could fit on even the lightest modern frigates in the US Navy. Spanning the early sixties to the new millenium, the Seasprite served as an able light transport, search and rescue, and anti-submarine helicopter before finally being phased out by the UH-60 Seahawk.

Whirlybirds

Of all the world’s navies, that of the United States was the first to employ helicopters enmasse. While helicopters had undergone considerable development since the first usable designs had been conceived in the 1920s, they remained a clumsy novelty into the 1940s. This was until the Sikorski R-4 was developed. Igor Sikorski, born in the Kiev Governorate in the reign of Alexander II, was already an aviation legend before the Russian Civil War saw him emigrate to the United States in 1919. Having previously designed four engine biplane airliners in the Russian Empire, and several of the flying boats that saw Pan Am span half the globe, Sikorski was a name known for breaking new ground. His R-4 helicopter would build this reputation further. The greatest advantage the R-4 had over its foreign contemporaries, most notably the Focke-Anchleis 223, was its simplicity and ruggedness. The use of a main lifting rotor and anti-torque tail rotor would prove a far lighter, and more robust method of control than the transverse and intermeshing rotors that drove a number of contemporary types.


Igor Sikorskiy (right) aboard a test flight of his R-4 helicopter (wikimedia).

The R-4 reached the notice of the US armed forces through Commander William J. Kossler of the Coast Guard, after the officer had seen the XR-4 undergo a test flight in April 1942. Impressed, he invited fellow officer CDR W.A. Burton to see the helicopter. The report on the aircraft took note of its ability to conduct patrols at low speeds, and unlike US Navy airships, did not require a large hangar for storage. Initially skeptical, the Navy was later convinced of the aircraft’s anti-submarine and convoy surveillance properties. Limited production began in 1942 and testing was conducted through 1943 and ‘44, though its sub chasing capabilities were not pursued. Instead, the helicopter proved itself as an air rescue vehicle. Its first trial came on January 3, 1944, when it delivered vital blood plasma from New York City to Sandy Hook, New Jersey, through a violent storm, in order to treat sailors after a fire had sunk the destroyer USS Turner. In all, several dozen R-4s would be delivered to the Coast Guard and Navy, where they took part in a number of rescue missions across North America and the Pacific.

While the R-4 was still limited in its carrying capacity and presented pilots with challenging flight characteristics, it demonstrated the utility of helicopters to every branch of the US armed forces. Sikorski would capitalize on this over the coming decade with their heavy H-19 and H-34 helicopters. Entering service in the early fifties, these helicopters were all metal and equipped with heavy radial engines. In civilian and military service, they would prove exceptional, capable of airlifting cargo to otherwise unreachable areas. However, a new, revolutionary advancement would soon render them obsolete. In 1955, the French Allouette II became the first production helicopter to feature a geared gas turbine. The turbine provided a far better power to weight ratio than the radial engines, and it was compact, allowing it to be placed at the center of the helicopter and thus avoided the forward engine placement that made some earlier helicopters nose heavy. This engine also allowed the nimble Alloutte to possess a speed and range far beyond comparable piston engined models. From then on, it was clear that turbine power would be the future of helicopter design.

 

A Sikorsky ‘Choctaw’ helicopter hovers to recover astronaut Alan Shephard and a Mercury reentry capsule after the first manned US space flight. The addition of a powerful radial engine made these among the first successful heavy lift helicopters. (wikimedia)

In the US, the first experiments for this type of helicopter propulsion were pioneered by Charles Kaman’s aircraft company. The first successful experiment was achieved through combining the Boeing 502 turbine with his company’s K-225. Kaman, a former employee of Sikorsky, would develop this new helicopter along with his head designer, Anton Flettner, a German engineer who pioneered the use of intermeshing rotors. The experimental K-225 proved promising enough to warrant further development, and soon, the Kaman Aircraft company would produce a new utility helicopter along its lines. The firm’s HH-43 Huskie fire fighting and rescue helicopter fit the bill, and its later models were equipped with turboshaft engines in the late 50s.

 

However, the firm’s greatest success was soon to arrive, when the navy sent out a request for a new carrier-borne, lightweight helicopter.

Seasprite

The US Navy’s request for a light multipurpose and rescue helicopter was soon met with Kaman’s newest design, the Kaman Seasprite. The helicopter would settle the requirements, being capable of carrying up to 12 people, remaining compact and fuel efficient, and taking up little space aboard aircraft carriers. In the 1956 competition, Kaman’s design won handily and the next year saw a contract issued for procurement. The helicopter was the first Kaman design to feature a single main rotor, and in conjunction with the servo-flap rotor system, it was cutting edge, reliable, and possessed smooth flight characteristics.

The design, then named HU2K, first flew on July 2, 1959, and was introduced fully in December 1962. It proved to be robust with good handling, however, the single General Electric T58GE turbine left it fairly underpowered. This prevented it from taking on any new missions, but it was sufficient for the basic role it was designed for. These helicopters, later designated UH-2A and UH–2B, though largely identical, were produced until 1965, with a total of 142 airframes built.

A Kaman UH-2A/B flies alongside the USS Enterprise as a plane guard as it launches a Grumman E-2a Hawkeye. (wikimedia)

The Seasprites, supplied to utility helicopter squadrons, were distributed amongst US aircraft carriers and saw widespread use during the Vietnam War. There, they served largely as plane guards, where they took up a position alongside aircraft carriers when large scale air operations were underway. In case of an accident during take off or landing, the Seasprites would move in quickly to recover downed pilots. Search and rescue also fell under their purview, and alongside a number of other models, they pulled hundreds of airmen from the sea. As a fleet utility helicopter, they also flew ashore and between various vessels in order to transfer personnel and equipment. Medical evacuations were also among tasks these helicopters performed, moving injured personnel to ships with more substantial medical facilities. The small size and smooth controls of the Seasprite made landing on the basic helicopter facilities of most ships an easier affair compared to the bulkier Sikorsky Sea King. Its only drawback was the relatively little power offered by its small turbine engine. It could make for tricky takeoffs as the small helicopter was slow to climb.

In spite of it being underpowered, it proved to be a valuable asset to the fleet and was respected by its pilots. Naturally, the Navy wished for improved models. Kaman’s first move was to add a second turbine engine to the helicopter, the improved model being the UH-2C. As the production run had already been completed, the Navy sent Kaman the older A and B models back to the company in order to receive the upgrade. The C model was introduced in 1966, though now with its much higher speed and carrying capacity, it was soon deemed that the Seasprite was to take on a much wider scope of duties.

Sub Chaser

During the late sixties, the increased threat posed by ever more advanced models of submarines was of great concern to the US surface fleet. Even more concerning was a lack of long range anti-submarine weapons. While many ASW vessels did carry the ASROC missile, tipped with either a nuclear depth charge or a Mk 46 torpedo, there was some concern of submarines attacking from beyond the 6 to 8 mile range of this weapon. The existing long range anti-submarine weapon was the Gyrodyne DASH drone, a small drone helicopter capable of carrying depth charges and torpedoes. While it was compact, it was inflexible, and with no means of collecting additional data in the area of the suspected submarine, accuracy was very poor.

The UH-2D was an interim ASW model to test the helicopters ability to carry the equipment needed for the role. These are differentiated from the later 2F’s by their tail wheel being further out. This aircraft lacks the sonobuoy rack. (wikimedia)

This left most of the US Navy’s light surface forces, which often operated too far from the carrier to be covered by its airborne ASW umbrella, under threat from more modern submarines. The solution was found in the re-engined Seasprite. The new SH-2D represented the greatest change thus far, with the new aircraft sporting a chin mounted surface search radar, a rack to carry a Mk 46 lightweight torpedo, and a 15 chute sonobuoy rack. The small size of the helicopter would allow it to operate aboard some of the lightest frigates in the fleet, these being the Garcia-class.

The performance of the helicopter, and its ability to operate on nearly every major surface combatant, would see this mission expanded even further. Thus came the Light Airborne Multi-Purpose System, a fleet-wide program to equip most warships with helicopters in order to boost their anti-submarine and anti-surface capabilities. LAMPS I would place a now standardized SH-2F aboard nearly every frigate, destroyer, and cruiser in the fleet. In addition to the long standing utility missions, the helicopters were datalinked to their host ship to allow them to prosecute possible submarine contacts, provide long range surface surveillance, and allow for more effective over the horizon targeting of enemy surface threats.

The new SH-2F was largely the same as the proceeding UH-2D model, though it standardized the use of composite rotor blades which existed on some previous models, and its tail wheel was moved forward to enable it to better operate off of smaller ships. Some 85 Seasprites were converted to this type, and a further 48 were produced in the early 80s in order to cover a shortfall before the introduction of the SH-60B Seahawk. The new, standard LAMPS helicopter entered service in 1973.

LAMPS I

The LAMPS I program vastly increased the offensive and surveillance capabilities of participating vessels. This encompassed some half dozen ship classes ranging from the workhorse frigates of the fleet, such as the Knox and Oliver Hazard Perry, to the nuclear guided missile cruiser, Truxton. In the ASW mission, on detecting a suspected submarine, whether attacking or transiting, the ship would launch its SH-2F. Capable of using sensor data from the ship, the helicopter would move in and begin to deploy its sonobuoys, being either passive AN/SSQ-41’s or active AN/SSQ-47’s. The helicopter then relayed the sonobuoy data back to the ship for processing, and if the contact was found and classified, the helicopter would move in to attack with its Mk 46 torpedo. The onboard magnetic anomaly detector could also mark the position of a submarine if over flown by the helicopter. A ship equipped with ASROC could also join the helicopter in the attack, provided the target was in range. In the ASW role, the helicopter was a largely reactive measure, as it was unable to process its own sonobuoy data and lacked a dipping sonar, and thus required other platforms to detect the submarine first. This is not to say it lacked considerable offensive potential, as the powerful hull mounted sonar arrays aboard the Knox class frigates and Spruance class destroyers, and the OHP’s short range but highly sensitive sonar, were among the most advanced systems of their kind and could give early warning to submerged threats. The presence of the helicopter thus allowed ships to prosecute, classify, and engage submerged contacts that would otherwise be beyond the effective range of their sensors and weapons.

The Spruance class Destroyers were among the most capable anti-submarine warships used during the Cold War. With their advanced sonar systems and two helicopters, they could pose a serious threat to even the most modern nuclear submarines. (National Archives)

The Spruance class in particular could prove very dangerous to submarines at range thanks to its convergence zone sonar. The AN/SQS-53 could make use of the aforementioned phenomenon, and under ideal conditions, detect submarines at extreme ranges. These zones are where sounds are bounced off the seafloor or thermal layers into a concentrated area and are thus made dramatically louder. Convergence zones are exploited by all ASW vessels, though the specialized sonar aboard these ships allowed them to exploit sound propagated at distances far in excess of the norm. A Spruance class ship making use of a convergence zone could dispatch helicopters against submarines potentially dozens of miles away, making them among the most capable ASW vessels of the Cold War. In the absence of a convergence zone, it switched to a short to medium range mode. It shared this system with the Ticonderoga class guided missile cruiser, and the Kidd class destroyer, both of which used the same hull, however their role was air defense. These ships all transitioned to LAMPS III once it became available in the mid 1980s.

The LAMPS system featured most prominently in escort and screening vessels, namely the Knox and Oliver Hazard Perry (OHP) class frigates. The Knox class was an anti-submarine frigate with limited anti-surface capability that entered service in 1969, with 46 vessels being commissioned in all. These ships carried a single Seasprite and were armed with an ASROC launcher, which later received the capability to launch Harpoon anti-surface missiles. The OHP class carried no ASROC launcher, though they instead carried two helicopters. The last 26 of the class were LAMPS III ships and carried the heavier and more capable Sikorski Seahawk. In place of the ASROC launcher was a Mk 13 mod 4 launcher for Standard missiles and Harpoons. Both frigates carried hull sonar and towed arrays, the Knox possessing a larger hull array, and the OHP carrying a short range, high resolution hull sonar system, with a towed array being used for longer range surveillance. The difference in systems was due to the OHP being designed as a fast escort, and needed the capability to conduct passive sonar searches at speeds faster than a typical surface group. The resulting hull sonar system was thus highly sensitive, but had a decreased maximum effective range.

The Knox class was initially classified as a destroyer escort and later designated as a frigate. For mid to late Cold War vessels, they were very capable anti-submarine patrol vessels for their size with good anti-surface capabilities, featuring both a dual purpose ASROC-Harpoon launcher and a LAMPS I helicopter. (wikimedia)

In addition to the added anti-submarine mission, the Seasprite performed anti-surface support and anti-ship missile defense roles. In performing these missions, the Seasprite used its search radar to track and identify potentially hostile surface vessels. This allowed the host vessel to build a picture of enemy forces while putting itself in comparatively little direct danger. With this information, any LAMPS I vessel had early warning against potentially hostile surface vessels, and could also use the relayed information to more accurately fire Harpoon and Standard missiles over the horizon, without using its own radar and revealing itself. The extended surveillance range of a LAMPS vessel was pushed beyond 170 miles with the use of the Seasprite.

LAMPS I thoroughly improved the anti-submarine and anti-surface capabilities of much of the US fleet, with the Seasprite itself being an almost perfect off the shelf solution. While there were limitations, like the inability to perform an independent ASW search, the overall benefit of the ship not needing to prosecute sub surface contacts alone or having to reveal itself to perform a radar search in its patrol area was well worth the resources devoted to the Seasprite.

Late Career

Beyond ASW duties, Seasprites also allowed their host vessels to conduct surface surveillance over a much wider area. Here, an SH-2F identifies a natural gas carrier during Operation Desert Shield. (National archives)

By the end of the Cold War, the Seasprite had incorporated a number of improvements. These comprised a number of on board and weapon systems, perhaps most notably the introduction of the Mk 46 Mod 5, or NEARTIP, lightweight torpedo. The new model was designed to counter the latest advancements in Soviet nuclear submarine design, with the torpedo possessing an improved engine to make for a higher speed, an improved sonar transducer to increase the effective detection range of the weapon and add better countermeasure resistance, and had a new guidance and control group. The new weapon entered service in 1979, with kits being produced to convert old stocks to the new standard.

An improved model of the helicopter equipped with T700-GE-401 engines was also developed in 1985, though few were procured, as the Navy sought to increase supplies of the SH-60 Sea Hawk. Some of the improvements from the scaled back Super Seasprite did however make their way into the SH-2F. A number of LAMPS I helicopters during the mid 80s were equipped with FLIR pods for IR searches, IR jammers, chaff and flare dispensers, and an infrared sea mine detection system. Their service during the Gulf War saw them mostly perform ship to ship material and personnel transfers, mine detection, and medical evacuation roles, as Iraq possessed no submarines. Their primary mission in the theater was mine hunting duties, for which they used IR sensors in their search. They were only carried aboard lighter surface combatants during Operation Desert Storm, and weren’t present among the air wings of any of the aircraft carriers during the conflict.

After almost thirty years of service, the SH-2F was withdrawn along with most of the vessels that carried them. Its end was hastened by the withdrawal of the Knox class frigates from service and the sale of most of the short hull OHP frigates to foreign navies. The Navy would fully transition over to the Sikorsky Seahawk, a much larger and more powerful helicopter which carried two torpedoes, a dipping sonar, and incorporated sonobuoy processing capabilities.

Construction and Flight Characteristics

The Kaman SH-2F Seasprite was compact, and while conventional for a modern helicopter, was very advanced for its day. Its fuselage was watertight, possessed forward retractable landing gear, and was equipped with a variety of onboard sensors. While it could not perform waterlandings, its sealed canopy allowed it to float until the helicopter’s crew could be recovered. The pilot sat on the port side of the cockpit and the copilot/tactical coordinator, who operated the weapon systems, was seated starboard. The systems operator sat behind the pilot and operated the sonobuoy dispenser, the magnetic anomaly detector, and radar system. The systems operator lacked the equipment to process the sonobuoy data, which was instead processed aboard the LAMPS I host vessel and sent back via a data link.

An SH-2F instrument panel (wikimedia).

At the nose of the helicopter was the LN-66 surface search radar, designed for detecting both surface vessels and submarine snorkels. On the starboard pylon was the MAD streamer which worked in conjunction with an extendable antenna on the underside of the helicopter. This system worked by measuring the local strength of Earth’s magnetic field, and would spike if it encountered a large magnetic object, or in other words, a submerged submarine. Triggering a readable detection required the aircraft to over fly the contact and was thus typically used to pin the exact position of the submarine while preparing to attack after closing in during the sonobuoy search. The Seasprite carried a mix of AN/SSQ-41A passive and AN/SSQ-47B active sonar sonobuoys. The AN/SSQ-41A omni-directional passive sonobuoys operate at a depth of 60 ft for shallow searches and 300 ft for deep, and have a frequency range of 10 Hz to 20 kHz. Depending on their settings, they lasted between one to eight hours. The SSQ-47B active sonobuoy provided ranging information and operated at either 60 or 800 ft and possessed a maximum endurance of thirty minutes. Sonobuoy data was processed aboard the supporting ship and was used to localize submarine contacts that were otherwise too distant or quiet to be effectively tracked by the ship’s sensors alone. The information provided from the data link allowed the helicopter to detect, classify, and engage subsurface contacts in cooperation with the host vessel.

Re-detecting a submarine at longer ranges from the ship was difficult, as passive sonobuoys laid out in a large search pattern gave little chance of success. The best chances of re-detection on a lost contact was when it was near the surface, transiting, or maneuvering to avoid attacks from other vessels and aircraft. The standard procedure for sub chasing was to head down the azimuth of the ship’s sonar contact and to begin to lay a sonobuoy field to uncover its exact location.

The Systems operator station. To the left is the MAD readout, in the center is a scope for the surface search radar, and on the right is the (shuttered) sonobuoy display. (National archives)

The Seasprite was initially powered by a single General electric T58-GE-8F turboshaft before a second was installed on the UH-2C. These each produced up to 1,350 shp and allowed the SH-2F to travel at a top speed of 152 mph at sea level and allowed the small helicopter to carry up to 2000 lbs worth of equipment in the vertical replenishment role, with a maximum cargo hook capacity of 4000 lbs. To save fuel during emergencies, the helicopter could run on one engine on the way back to the ship. These engines were well regarded and considered very reliable.

The helicopter’s lift was provided by a 44 ft main rotor which used composite blades which were directed with servo operated flaps. These flaps are easily visible on the rotors, each having a wider chord than the rest of the blade. The flap is used to change the angle of attack of the rotor in flight and allows for smooth altitude adjustment. The anti-torque rotor at the rear of the helicopter had its blades increased from three to four going from the C to D model. The Seasprite handled well and was easy to perform a hover in, an important capability when it comes to search and rescue, and transfers to vessels without any landing areas. This was particularly important when landing on Knox class frigates, which both had significant air disturbance aft of the ship, and a very claustrophobic landing area.

In the air rescue role, the copilot would coordinate with divers and rescue crew. The cargo space of the helicopter could fit two stretchers or three seats. For water recovery of personnel, divers were carried aboard and recovered downed airmen through the use of a rescue hoist mounted on the starboard side of the helicopter. Mechanically driven, it had a capacity of 600 lbs.

Throughout the 1980’s, Seasprites were often equipped with a variety of new devices. This aircraft features two ALQ 144 IR jammers for missile defense, chaff and flare dispensers, and a FLIR imager. Crews also often removed the doors from these helicopters for faster entry and exit. (National Archives)

The Seasprite could carry a variety of unguided weapons, but rarely carried anything other than the Mk 46 torpedo, being either the Mod 0, or Mod 5 NEARTIP during the 1980s. On paper, the Seasprite could carry two torpedoes, but in practice, the second equipment position was taken up by an external fuel tank on ASW patrols. Both torpedo types measured 8.5 ft long with a diameter of 12.75 inches. The Mod 0 weighed 568 lbs, and both carried a 95 lb warhead. The Mod 0 possessed a maximum speed of 45 kts, with the NEARTIP being considerably faster. The NEARTIP provided better tracking of faster targets and better countermeasure rejection, having incorporated a new sonar transducer, control and guidance group, and a new engine which switched from solid propellant to liquid monopropellant. Prior to the introduction of the Mod 5, there was little hope for successful attacks against the fastest nuclear submarines of the 1970s. However, in confirming the location of a submarine, its position also became revealed to long range ASW aircraft which could make follow up attacks.

Other weapons included unguided 2.75 inch unguided rockets, and some rare, late examples possessed FLIR optics and could carry AGM-65 Maverick missiles. These weapons, however, were rarely ever carried. Later Seasprites carried a variety of countermeasures including an ALQ-144 tail mounted IR jammer and an ALE-39 flare and chaff dispenser. A considerable number of these helicopters were equipped with infrared jammers and flares during the 1980s.

Conclusion

An SH-2F is being used to evacuate a sailor who received severe burns, necessitating treatment off-vessel. (National Archive)

The Kaman Seasprite can be said to be among the most versatile aircraft ever operated by the US Navy. Entering service as a plane guard, the number of roles it served grew considerably over the years to encompass everything from medical evacuation, to anti-submarine duties. As the core of the LAMPS program for nearly 10 years, it gave US warships a boost in their offensive and defensive qualities against both surface and subsurface opponents.

Specification

SH-2F Seasprite Specification
Engine 2x General Electric T58-GE-8F
Output (maximum) 2300 SHP (2700 SHP)
Maximum Weight 12800 lbs
Empty Weight 8652 lbs
Range for Utility 234 N.MI
Radius of Action for Utility 111 N.MI
Endurance for Utility (ASW) [Ferry] 2 hours (1.9 hours) [2.8 hours]
Standard Armament 1 Mk 46 Mod 0/5 Lightweight torpedo
Crew Pilot, copilot/tactical coordinator, systems operator
Length of fuselage 40.5 ft
Width of fuselage 10 ft
Designation Sub type
HU2K/UH-2A Basic single engine utility helicopter
UH-2B Minor differences in avionics, later made identical to A model
UH-2C First two engine model
H-2 Army project, single engine
HH-2C Combat rescue model, 7.62 side door gun emplacements, M134 rotary gun turret. Two engines.
HH-2D Same as HH-2C but without armament. Used to test ASW equipment and loading. Two engines.
NUH-2C/D Test helicopter, two engines.
YSH-2E Testing helicopter for radar and ASW gear for canceled LAMPS II program
SH-2D Early ASW model
SH-2F Standard LAMPS I helicopter
SH-2G SH-2F with T700 turboshaft engines, improved avionics. Small production run.
Avionics Type
Surface Search Radar LN-66HP
IFF AN/APX-72
Transponder Computer KIT-1A/TSEC
UHF Radio Set AN/ARC-159
Secure Speech KY-28
ICS AN/AIC-14
TACAN AN/ARN-52
Doppler Radar AN/APN-182
Attitude Heading AN/ASN-50
NAV Computer AN/AYK-2
Plotting Board PT-492
UHF Direction Finder AN/ARA-25
OTPI R1047A/A
Radar Altimeter AN/AP-171
RAWS AN/APQ-107
Sonobuoy receiver AN/ARR-52
Acoustic Data Processor AN/ASA-26B
Data Link AN/ASK-22
Magnetic Anomaly Detector AN/ASQ-81
Radar Warning Receiver AN/ALR-54

Profile:

The SH-2F Seasprite was a simple, but excellent conversion of a proven airframe. Installed aboard much of the US surface fleet, it was a potent force multiplier.
During the mid 80’s, the Seasprite fleet received a number of improvements. These included the ALE-39 countermeasure dispenser, the AN/ALQ-144 IR jammer for use against heat seeking missiles, and later FLIR optics.

Gallery:

 

The Knox class’s helicopter facilities were quite claustrophobic, and precluded the use of a larger helicopter. (National Archive)
A forward view of a Seasprite aboard a Spruance class Destroyer. (National Archives)
Despite its small size, the Seasprite could carry a considerable sling load between vessels. (wikimedia).

A Knox class frigate during a visit to La Roche, France with its LAMPS helicopter on deck. Curiously, this ship’s Sea Sparrow launcher has been removed. (Wikimedia)
The colorful MAD streamer. (Wikimedia)
A Seasprite responds to a medical emergency aboard a freighter near a naval exercise. (National Archives)

A Seasprite flies as a plane guard alongside the USS America. An Essex class refit carrier sails in the background. (National Archives)
An SH-2F undergoes checks aboard the USS Iowa during the Northern Wedding naval exercise, 1986. (National Archives)

A small number of combat rescue helicopters were converted to recover airmen from potentially dangerous coastal areas. In practice, the nose mounted gun was typically not retained. (wikimedia)
With its rotors folded, the crew of the USS John Hancock prepare to stow their Seasprite. (National Archives)
A snapshot taken by a Seasprite: Soviet Submarine K-324 and frigate USS McCloy (Knox class) were engaged in mutual surveillance when the submarine’s screw became entangled in the frigate’s towed sonar array. The emergency was responded to by the Soviet oceanic survey ship SSW 506 and the American destroyer USS Peterson. The K-324 was a Victor III class nuclear submarine, this type being the most numerous modern Soviet nuclear submarine of the late Cold War.

Credits: 

  • Article written by Henry H.
  • Edited by  Stan L. and Henry H.
  • Ported by Henry H.
  • Illustrations by Godzilla

Sources

Primary:

Standard Aircraft Characteristics Navy Model SH-2F aircraft. NAVAIR 00-110AH2-8. Commander of the Naval Air systems Command. July 1974.

Andrews, Harold. Sea Sprite. Naval Aviation New 1983 (Feb).

Naval Aviation News 1985 (May-June)

Naval Aviation News 1983 (Jan-Feb & May-Aug)

Department of Defense authorization for appropriations for fiscal year 1982 : hearings before the Committee on Armed Services, United States Senate, Ninety-seventh Congress, first session, on S. 815.

Department of Defense appropriations for 1984 hearings before a subcommittee of the Committee on Appropriations, House of Representatives, Ninety-eighth Congress, first session / Subcommittee on the Department of Defense.

Department of Defense authorization for appropriations for fiscal year 1986 : hearings before the Committee on Armed Services, United States Senate, Ninety-ninth Congress, first session, on S. 674.

Department of Defense authorization for appropriations for fiscal year 1979 : hearings before the Committee on Armed Services, United States Senate, Ninety-fifth Congress, second session, on S. 2571

Department of Defense authorization for appropriations for fiscal year 1980 : hearings before the Committee on Armed Services, United States Senate, Ninety-sixth Congress, first session, on S. 428.

CDR Rausa Rosario. LAMPS MK III. Naval Aviation News 1980 (June).

Defense Department authorization and oversight hearings on H.R. 5167, Department of Defense authorization of appropriations for fiscal year 1985, and oversight of previously authorized programs before the Committee on Armed Services, House of Representatives, Ninety-eighth Congress, second session.

Secondary:

Polmar, Norman. Ships and Aircraft of the U.S. Fleet. Fifteenth Edition. US Naval Institute Press. 1993.

Sikorsky HNS-1 “Hoverfly”. United States Coast Guard.

Stuyvenberg, Luke. Helicopter Turboshafts. University of Colorado at Boulder, Department of Aerospace Engineering. 2015.

Garcia Class Frigate. NAVsource online.

Yakovlev EG Side View Illustration

Yakovlev EG

USSR flag USSR (1946)
Coaxial Rotor Helicopter – 1 Built + 1 Incomplete

The modified Yakovlev EG prototype in flight. (Yakovlev OKB) Colorization by Amazing Ace

The EG (also known as the Yak-M-11-FR-1, Sh or Yak-EG) was a prototype helicopter designed in 1946 by the Yakovlev OKB. The EG was designed with a coaxial rotor configuration and had an ambitious performance estimation. Through manufacturer testing, it was revealed that the EG had very undesirable handling characteristics and excessive vibrations when the helicopter reached around 20 mph (30 km/h). These flaws caused the cancellation of the EG project and the completed prototype was converted to an aerosani in 1955 and donated to a farm in the Kazakh SSR. The Kamov OKB would later go on to develop the coaxial rotor configuration further.

History

Lessons of the Second World War showed the world the importance of adopting and developing modern technologies. Throughout the war, autogyros and helicopters became increasingly relevant with several countries’ militaries and saw a dramatic increase in development. The Soviet Union had a very limited selection of these machines during the war, and looked to develop this technology and expand their arsenal. In 1946, the esteemed Yakovlev OKB initiated a project for an experimental coaxial rotor helicopter design. The project was given the nickname of “EG”, for “Experimental Helicopter” (Экспериментальный Геликоптер / Eksperimentahl’nyy ghelikopter). When the task of designing the EG was first announced to the design team, a flabbergasted staff member exclaimed “Shootka?” (шутыш), which roughly translates to “Are you kidding?”. This then led the EG to unofficially be referred to as the “Sh”, a running joke in the design team. Another designation which referred to the EG was “Yak-M-11FR-1”, which referred to the engine that the helicopter would use. The origin of this designation is unknown, but it does not appear to be official.

A detailed cutaway drawing of the modified Yakovlev EG prototype. (Yakovlev OKB)

Responsibility over the project was given to chief designer S.A. Bemov, with I.A. Erlikh as his aide. The EG was envisioned as a coaxial rotor configuration while powered by a 5-cylinder air-cooled Shvetsov M-11FR-1 radial engine producing 140 hp. When the initial design was completed in early 1947, the design team built a flying scale model of the EG to prove the viability of the coaxial rotor design. The scale model was given the designation of ED 115, with the digits referencing OKB-115, the plant designation for Yakovlev OKB.

The modified prototype Yakovlev EG sits on the Yakovlev OKB’s premise with it’s rotor fins folded. (Yakovlev OKB)

After verifying the EG’s design, construction of the actual prototype commenced. The prototype was completed sometime in the summer of 1947 and was promptly subjected to manufacturer’s trials. The EG prototype performed 40 tethered flights (total of 5 hours flight time) before being authorized to perform the first free flight test on December 20, 1947. Through extensive testing, it was revealed that the center of gravity was too far to the rear, which led the team to remove the tail and tailskid and relocate the oil tank behind the cockpit. In early 1948, the M-11FR-1 engine was removed, replace by an experimental M-12 radial engine, a development of the M-11. The first test flight with this engine was conducted on April 9th, but the engine proved troublesome and forced the team to refit the M-11FR-1 engine. Flight tests continued until July 8, 1948, with a total of 75 free flights conducted (total of 15 hours flight time).

Despite the EG showing relatively decent results, it suffered from excessive vibration, loss of stick force and phugoid instability once the machine approached 20 mph (30 km/h). This severely restricted the EG’s practicality and thus warranted the project’s cancellation. The coaxial rotor design configuration was given to Kamov OKB to further develop, while the Yakovlev OKB moved onto more conventional helicopter configurations. A second prototype was in construction but was never completed and was scrapped when the program was canceled. The sole completed prototype was preserved at the Moscow Aviation Institute for a couple of years before being converted to an aero-sleigh by students between 1954 and 1955. The converted sleigh was then donated to a farm in the Kazakh SSR and the fate beyond that is unknown. Photos of this new conversion do not exist. Though ultimately ending up as a failure, the EG was an important stepping stone in Soviet helicopter development and was quite special in the sense that it was the Yakovlev OKB’s first helicopter design.

Design

The original configuration of the Yakovlev EG with a horizontal tail, tail bumper and endplate fins. (Yakovlev OKB)

The Yakovlev EG was a coaxial rotor helicopter powered by a 5-cylinder air-cooled Shvetsov M-11FR-1 radial engine producing 140 hp. The engine drove co-axial two-bladed rotors using a transmission system which featured a centrifugal clutch, a 90-degree gearbox and a cooling fan. Fuel tanks were placed under the gearbox while the oil tank was next to the engine. The rotors (made of laminated pine and hardwood) spun in opposite directions at 233 rpm. Both collective and cyclic pitch control was provided through the rotor’s fully articulated hub mount. The EG’s fuselage consisted of simple welded steel tubes which had D1 duraluminium skin all around except for the engine compartment. The rear fuselage, which was covered with fabric, gradually tapered off to form a fin which was accompanied by a horizontal stabilizer supplemented by two endplate tips. The tail and the horizontal stabilizer would be removed later on in the test phase due to the offset center of gravity. The EG had a non-retractable tricycle landing gear with vertical shock absorber struts. The glazed cockpit compartment could house two pilots, which would enter through doors on either side of the fuselage.

Operators

  • Soviet Union – The Yakovlev EG was designed with the intent of serving the Soviet Union. The EG was evaluated by Yakovlev OKB but was deemed to be unfit for service due to the excessive vibration and loss of stick control and phugoid instability when the helicopter reached speeds around 20 mph (30 km/h).

Yakovlev EG

Fuselage Length 21 ft 5.1 in / 6.53 m
Engine 1x 5-cylinder air-cooled Shvetsov M-11FR-1 radial engine (140 hp)
Rotor Diameter 31 ft 9.7 in / 10 m
Empty Weight 1,936 lb / 878 kg
Takeoff Weight 2,249 lb / 1,020 kg
Climb Rate 610 ft per minute / 3.1 m per second
Maximum Speed 58 mph / 93 km/h – Estimated

Approximately 43.5 mph / 70 km/h – Actual

Range 146 mi / 235 km – Estimation based on 58 mph / 93 kmh Top Speed
Hover Ceiling 820 ft / 250 m
Flight Ceiling 8,860 ft / 2,700 m – Estimated*

* – Testing never exceeded 590 ft / 180 m

Crew 1x Pilot

1x Co-Pilot

Gallery

Yakovlev EG Side View Illustration
Side View Profile of the Yakovlev EG by Ed Jackson
A desktop model of the Yakovlev EG. This model does not have the tail components presented. (Yakovlev OKB)
The modified Yakovlev EG prototype in flight. (Yakovlev OKB)
A side view of the original configuration of the Yakovlev EG with a horizontal tail, tail bumper and endplate fins. (Yakovlev OKB)
A side view of the modified prototype Yakovlev EG sitting on the Yakovlev OKB’s premise with it’s rotor fins extended. (Yakovlev OKB)

Sources

Denel Rooivalk

South African Flag South Africa (1990)
Combat Support Helicopter – 12 Built

Rooivalk Mk1 with full traditional weapons loadout. Visible is the MISTRAL ATAM launcher, M159 rocket launcher pod, ZT-6 Mokopa ATGM and GIAT 20 mm F2 duel feed cannon. Source DENEL.

The Rooivalk (Red Kestrel) Combat Support Helicopter (CSH) is considered by many as one of the most advanced weapon systems produced by the South African defense industry. It was designed and developed for the hot, humid, and dusty Southern African battlespace based on the lessons learned during the South African Border War (1966-1989) to operate in a high-intensity conventional war. According to the then Minister of Defence, Mr. Joe Modise (1994-1996), the Rooivalk represents a combat helicopter of world-class standard. The Rooivalk Mk1 allows the South African Air Force (SAAF) the needed flexibility to help maintain the country’s national security interest and project force where required, such as in the Democratic Republic of the Congo.

Development

With the South African Border War (1966-1989) operations shifting from low intensity to a high-intensity conventional war in 1985, the South African Defence Force’s (SADF) need for a dedicated attack helicopter capable of defeating enemy armor became paramount. South Africa had also become subject of the United Nations Security Council Resolution 418 on 4 November 1977, which imposed an arms embargo. This isolation would lead to South Africa having to develop an attack helicopter, as none could be sourced internationally (if the need ever arose).

The Atlas Aircraft Corporation, a division of the Armaments Corporation of South Africa (ARMSCOR), not only provided support for SAAF aircraft but also gained significant experience upgrading the SAAF Mirage IIIs in the 1970s. A project study was undertaken to come up with a workable configuration in 1976/8, which placed Atlas in the position to make a helicopter industrialization program. A significant point of debate was whether a small or large helicopter would be best. The latter would win out the subjective assessment, and objective operational analysis clearly showed a light helicopter would lack the range, payload, and survivability required in a high threat environment. The requirements for an attack helicopter included: survival in a high-threat regime, commonality with the existing medium transport helicopter fleet (Oryx/Puma), quick response to the mission task, day and night operability, low pilot workload, a very accurate navigation suite, simple “in-the-field” maintenance, an operational lifespan of 30 years, the ability to come quickly under existing Army command, control and communications systems, be operable in the “‘operational ”window’ (5-15 m above the terrain) for 95% of its lifetime, long-endurance capability, ability to ferry great distances and be built within the existing industrial infrastructure of South Africa. The future attack helicopter would place speed and maneuverability above protection to fulfill the prime objectives of mission success with maximum survival chance for both crew and aircraft.

When the requirement for an attack helicopter came to light, funds were made available to the Council for Scientific and Industrial Research (CSIR) to conduct a feasibility study. A signed contract with the SAAF in 1981 led to the development of the Alpha XH-1 prototype, which was based on the French Aérospatiale SA 326B Alouette III helicopter. The purpose of the Alpha XH-1 was to serve as a learning and capacity-building platform for South African engineers, supporting industries as well as testing various concepts and systems. This development resulted in much of the components, such as the engine, gearbox, and rotor systems, being produced in South Africa. Unlike the Alouette III, the prototype had a semi-monocoque airframe. It featured a GAI Rattler 20 mm cannon on a steerable turret under the aircraft’s nose, controlled by the weapons officer’s Kukri helmet-mounted sight. The Alpha XH-1 was never regarded as anything more than a test platform for hardware development. The Alpha XH-1 flew for the first time on 2 February 1985. It flew only a few times, as the main Attack Helicopter project had surpassed its need. The XH-1 was revealed to the public in 1986.

Meanwhile, Atlas Aircraft Corporation continued with its helicopter industrialization program to build capacity to provide more critical components for the Alouette family and Aérospatiale SA330 Puma helicopters in service with the SAAF. Further development of systems, such as avionics and weapons, required testing, which resulted in the purchase of two Puma 330Js which would serve as testbeds to support parallel development activities. The first of these helicopter’s, Experimental Test Platform 1 (XTP-1), also known as Puma J1, flew in 1986 and featured locally developed avionics and weapon systems, as well as a fully configured flight test engineering station in the cabin that recorded test parameters, as well as the ability to vary several input flight parameters in the development of higher mode autopilot functions. Also included were cockpit workload assessments during simulated anti-tank missions and aerodynamic effects of the stub-wings through the flight envelope. The XTP-1 was revealed to the public in 1987.

 

The Puma J2 loaded with V3 air-to-air missiles, ZT3 anti-tank missiles, and fitted with a belly-mounted 20 mm cannon. Courtesy of: Rooivalk – a legend in the making

The second Puma J, J2, was similarly configured as J1 and flew shortly after J1. J1 was mainly used as the test platform for systems development, and J2 was used to test the weapon systems with actual weapons firing. Extensive testing was carried out on the blast effect of the ZT3 anti-tank missile and recoil force of firing the 20 mm cannon, aerodynamic interaction, and drag between the various mounted weapons, resonance, thermal dissipation, and power consumption. Both Puma Js featured stub-wings mounted on the cabin sides, which carried two 18 round 68 mm rocket pods, two four-tube ZT3 ATGM launchers, in addition to the ventral mounted turret with a 20 mm GA-1 canon linked to the weapon officer’s helmet-mounted sight. Two missile tests were conducted. The first, in December 1988, at the St Lucia test range, was meant to determine the blast effect of the ZT3 missile on the helicopter’s tail boom and the accuracy of the weapons and supporting systems. Of note is the accuracy of the ZT3 anti-tank missile, which hit a stationary target 5km away being just 450 mm off the target center. The second test occurred in 1989 and involved a combination of the 20 mm cannon, 68 mm rockets, and ZT3 missiles in determining the post-launch maneuvers and different types of operations.

In parallel to the Rooivalk development, the Medium Transport Helicopter (MTH) requirement was also being industrialized, and Atlas was being set up to manufacture common parts for both Oryx and Rooivalk, such as the main rotor and tail rotor blades, the full transmission system including gearboxes and engines, and various subsystems to the point where the Oryx, as an upgrade to the Puma, was born based on the Super Puma dynamics

The Rooivalk’s development began under the project name Chickadee in 1984, which became Impose as a later project name. Much of the technologies developed for the XTP-1 would find their way to the Rooivalk eXperimental Development Model (XDM). Its primary purpose was to test the aircraft dynamics, mechanical, aerodynamic, and structural design, flight performance, and to do weapons carriage clearance. The XDM was used in the first phase testing of the dynamic components, which included the engine, air intake system, propulsion system controls, lubrication, and cooling. It was suspended in tie town jigs and repeatedly subjected to startup, shutdown, and transient system operation, with the first test commencing on 21st December 1989. The XDM was rolled out on 15 January 1990, after nearly four years of construction. It flew for the first time on 11 February 1990, as part of its 20 hour endurance testing. By May 1992, it had amassed 180 flying hours. It was also during this time that the horizontal and vertical stabilizers were finalized in their optimized form. The vertical tail configuration is designed for high-speed flight and to optimize lateral stability and low-speed responsive yaw control. The XDM can be distinguished from the other airframes by the rounded ammo bin aft of the cannon, and the exhaust was initially without infra-red suppressors, although, later in the development program, the XDM was fitted with a set of development IR suppressors.

The XDM during the tie-down jig testing. Courtesy of: Rooivalk – a Legend in the Making

The contract for the Advanced Development Model (ADM) was placed in 1988, completed in 1992, with its first phase flight on 22 May 1992. The ADM was used to verify the avionics design and implementation, weapons development, and integration platform. The traditional instruments were replaced by three multi-function displays (MFD), and the avionics system proved to minimize the aircrew workload significantly. The Rooivalk ADM would be the first-ever attack helicopter to fly with an MFD” “glass cockpit”. The ADM featured the MIL-STD-1553B digital databus system and was equipped with ZT3 Ingwe ATGM missiles, as well as a 20 mm cannon mounted to a TC-20 chin turret. The second phase of testing commenced on 23rd July and lasted until 4th December 1992 and involved in-flight operation of the Integrated Management System, the Health Monitoring System, the Automatic Flight Control System, and the Communication System. The third phase of testing was focus on the weapon systems and included the nose-mounted Main Sight System (MSS), 20 mm cannon in August 1993, and ZT3 anti-tank missile in March 1994. Both weapons systems were successfully tested.

XDM again during the subsequent flight trials program. Courtesy of: Rooivalk – a Legend in the Making

The ADM made its international debut at the Dubai air show in 1993, followed by the Malaysia air show in 1993. In 1994, the ADM was on display at the Farnborough International Air show in England. With potential international exports in mind, the Rooivalk was developed according to US military requirements and standards, which would only require small adjustments to make it compatible with US weapons systems such as the Hellfire ATGM. Meanwhile, the SAAF was contemplating an order of 16 Rooivalks with an updated User Requirement Specification which specified a more powerful cannon and longer-range missiles. Although 36 Rooivalks were envisaged to complete three squadrons, cuts to the defense budget and a change in the defense force strategy resulted in only 12 being ordered.

The Engineering Development Model (EDM) was developed as a platform to incorporate lessons learned from the XDM & ADM, to incorporate the SAAF’s updated User Requirement, as well as for doctrine and mission development. Design and development began in March 1993. The completed aircraft rolled out on 17th November 1996 and a flight was presented on 17th February 1997 by Denel. The purpose of the EDM was to qualify the avionics, weapon systems, airframe, and airborne systems before serial production could commence. Additionally, the EDM was used to refine the required logistical support. With the EDM, the ammo bins were moved to each side of the cockpit and the infra-red suppressor exhaust was directed upwards into the main rotor blades to dissipate the heat more efficiently. Additionally, the EDM saw many structural changes, as well as weight reduction. It represented the beginning of the Rooivalk assembly line.

The Rooivalk ADM international debut during the Dubai 1993 air show. Screengrab from Paratus Magazine. Original photo by S. Basch
EDM 70 mm rockets loading (left) and firing (right) tests. Courtesy of: Rooivalk – a legend in the making

In 1994, the Rooivalk was entered into the UK Ministry of Defence (MoD) tender for an attack helicopter. An audit by the MoD in March 1994 allowed Denel Aviation to submit its Invitation to Tender (ITT). Although ultimately unsuccessful, the experience was invaluable for future tender processes.

On 2nd August 2005, Rooivalk 679 sustained damage when it suffered a hard landing testing a newly installed autopilot. The main rotors were damaged, and the tail boom broke off. The Rooivalk’s design philosophy of protecting the crew succeeded, as neither were seriously injured. It was deemed uneconomical at the time to repair and it was subsequently stripped of usable parts. In 2016, Denel was still in talks with the SAAF to make use of Rooivalk 679 as a prototype platform for further development. The full order of 12 aircraft was completed by 2004. The total cost is estimated at R6.2 billion in 2015 for the full development activity and the production run of 12 aircraft.

The first SAAF Rooivalk was delivered on 7th May 1998 and was subsequently upgraded in blocks, starting with 1A, up to its current 1F, which is referred to as Mk1 baseline. The SAAF would only take delivery of six fully operational and military certified Rooivalk MK1s in April 2011. The Rooivalk Mk1 included 130 modifications, such as improved sighting and targeting system, communications systems, gearboxes, self-protection, the ability to fire the Mokopa ATGM and improved reliability of the 20 mm cannon. Additionally, fuel drop tanks were added which became invaluable for self-deployment to the DRC. The remaining five aircraft entered service by March 2013.

In 2015, the South African Department of Defence was considering restarting the Rooivalk manufacturing. The acting chief executive of Denel, Zwelakhe Nshepe, stated in 2017 that the Rooivalk MK1 would hopefully lead to the next generation Rooivalk MK2, which would be aimed at the export market. It features better sights, more firepower, a higher payload, and increased survivability. It was noted that a minimum of 75 airframes would need to be ordered for the project to be financially viable. At the time, Brazil, Egypt, India, and Nigeria were identified as potential target markets.

Denel has approved the Rooivalk Mk1.1 upgrades and was negotiating with the SAAF on the matter as a midlife upgrade, already due in 2016.

South Africa is the only user of the Rooivalk Mk1 CSH, which is assigned to 16 Squadron at Bloemspruit Air Force Base in Bloemfontein.

Design Features

The Rooivalk’s mission was envisaged according to the role at the time of an armed helicopter in a conventional war. This included operations with mechanised forces, deep penetration into enemy territory, air defence suppression, counter helicopter and anti-armor operations, counter-air operations against airbases, helicopter escort missions, maritime patrol, and reconnaissance. Based on those requirements, the Rooivalk design philosophy centred around four pillars, namely not to be seen, if seen not to be hit, if hit to sustain flight and if the flight could not be maintained the pilots had to survive the crash.

Performance

The Rooivalk was designed to exceed the demands required during the first 24 hours of a high-intensity war while in unfriendly territory. The Rooivalk is powered by two Turbomeca Makila 1K2 turboshaft engines which produce 1845 shp (246 shp/t).

It has an empty weight of 5910 kg and a max take-off weight of 8750 kg, which equals a carrying capacity of 2840 kg. Its typical mission weight is 7500 kg.

Its broad performance envelope includes operating in temperatures of between -35° C to +50° C, being able to take-off and land between -3000 ft to +19200 ft, and have a flight altitude of 20000 ft. Its hover over ground effect is 5,029 m, which is comparatively high compared to the AH-64 Apache (3,866 m), Mi-28 Havoc (3,600 m), Ka-50 Kamov (3,600 m), and Eurocopter Tiger (3,200 m). At mission weight, it has a cruising speed of 278 km/h and a top speed of 309 km/h. It can fly sideways at 92 km/h. At sea level, it can ascend 670 m a minute (11 m/s) with a maximum hovering ceiling of 5,545 m and a service ceiling of 6,095 m.

The Rooivalk has a minimum endurance of 216 minutes and 412 minutes with external fuel drop tanks, allowing it to self-deploy some 1260 km. Its combat radius (when fully armed) is 740 km with reserve fuel.

The airframe is rated at +3.5/-0.5 g.

The Rooivalk ranks among the top helicopters with regards to cruise speed, operational range, rate of climb, weapons loadout and power to weight, which are all essential during combat operations.

Aircraft Layout

The airframe has a length of 16.39 m (nose to the rear wheel), height of 5.19 m (ground to rotor head fairing) and width of 6.95 m (from either side of the stub-wings). The diameter of the four composite blade main rotor is 15.58 m and expands to 18.73 m when rotating. The tail rotor is 3.05 m wide.

The fuselage consists primarily of aluminium alloy to save weight and access doors hinged to the central I-beam and made of composite material that allow easy access to the interior.

The aircrew stations are placed in a step, which reduces the glare from the sun associated with tandem designs. Access to either side of each station is via upward hinged flat bulletproof windows. The aircrew stations are ergonomically designed to reduce aircrew workload and fatigue, which enhances endurance and battlefield awareness. The aircrew station for the pilot seated in the rear and Weapon Systems Officer (WSO) seat in front make use of Hands-On Collective and Stick (HOCAS) controls. The dashboard features three MFD displays, which are vital, as the Rooivalk would spend 90% of its time between 5 – 15 m off the ground during a combat mission.

The engines are fitted alongside the main gearbox, with the rear output shaft aligned to drive the gearbox from the rear. The gearbox itself is mounted on a tuned beam (vibration Isolation System) to minimise vibration on the airframe. The engine air intakes are fitted with a highly efficient particle separator (to keep dust and debris out) with a 97% efficiency against particles of 10 microns. Air from the engines is directed upwards through infra-red suppressors into the rotor blade downwash to disperse the heat and reduce its Infra-Red (IR) signature.

The Rooivalk has three internal fuel tanks located in the middle of the airframe, under the stub-wings centre section, each with a 480 kg (total 1440kg) carrying capacity. It makes use of Jet A-1 type fuel.

The stub-wings are fitted on either side of the airframe and have a straight rectangular shape.

The landing gear is of fixed design and consists of two forward wheels on the forward section of the airframe and a tailwheel. The wheelbase is 11.77 m (38ft 7in) and the wheel track 3 m (9ft 10in).

Endurance and Logistics

During the South African Border War, the SAAF made extensive use of Alouette III and Puma helicopters, gaining valuable operational and logistical experience. The Rooivalk was subsequently designed to operate for extended periods with minimal support and maintenance in the field with basic spares which are transportable via Oryx helicopter. The airframe has many large access panels which make access simple, as no tools are needed. The stub-wings and cowling (cover over the engine) are functional as working stations, and no ground support equipment is needed. It can be maintained with a ground crew of four in the field with spares that can be flown in an Oryx. The ground crew’s task is made easier with onboard test functions and line replacement units. The Rooivalk’s overall design also incorporated easy refuelling and re-arming. The engine features highly efficient sand filters which help reduce wear and tear and extends service life.

Avionics and Weapon System

The Rooivalk makes use of the advanced international digital Military Standard (MIL-STD-1760B) Class 2 weapons station and MIL-STD-1553B avionics system. The systems allow total mission modes, target acquisition, flight control, health and usage monitoring, communication, threat detection, and control of flight and fuel.

The avionic system is fully digital and incorporates night vision goggle compatible glass cockpit technology for low light night vision. This allows accurate navigation, pre-programmable tactical flight plans with moving digital map and flight data projection on two liquid crystal multi-function display. The multi-function displays allow the aircrew to switch between navigation, flight control, weapons control, threat warning and imagery from the sensors when required.

Flight control avionics consists of a duplex four-axis digital automatic flight control system. The latter is coupled with ring laser gyros with navigation and position input from a radar altimeter, eight-channel GPS, Doppler velocity sensor, magnetometer heading sensor, air data unit and an omnidirectional airspeed sensor. All of these systems are linked to a dual redundant navigational computer.

The autopilot system makes use of an eight-channel Global Positioning System (GPS) and Inertial Navigation System (INS). The system allows for normal as well as higher mode linkage to the avionics and weapons system. The one-touch feature for auto-hover, altitude hold, follow a planned route and target orientation is based on the main sighting system. The former two features allow the aircrew to recover from vertigo which could occur during night time low-level tactical operations or poor weather.

 

WSO cockpit layout illustration, Courtesy of Rooivalk – a Legend in the Making

The nose-mounted gyro-stabilised sensor turret housing with auto-tracking contains the target acquisition designation sight known as the NightOwl system. The system was developed by Société de Fabrication d’Instruments de Mesure (SFIM), which was absorbed by the Société d’Applications Générales de l’Électricité et de la Mécanique (SAGEM) in 1999/2000. It consists of 3-FOV FLIR with automatic tracking, LLTV and laser rangefinder and designator. The three fields of view, which include thermal and low light displays, have recording function with playback facilities and sight cueing. This allows for pop-up missile engagements based on target location recorded during high threat situations. The missile command and control system is integrated with the avionic system, which provides continuous navigational updates, flight control handover and weapons computing parameters. The weapons system additionally provides weapons and stores management. The aircrew’s helmet-mounted sight displays both flight and weapon data and can both cue the turret-mounted GI2 20 mm cannon and other armaments.

All armament can be used by either the pilot or WSO, although the use of the Mokopa could be laser designated by sight or from an external source. The pilot can, for example, use the cannon and rockets to suppress enemy fire while the WSO fires the Mokopa. The pilot and WSO cue the primary sight via their helmet sight and thereby show the other a target of opportunity or imminent threat. The fire control system (FCS) allows the flight crew to pop up from behind cover, scan the surrounding area, drop back down and identify targets via video cassette recording playback function, select targets and attack or relay target information to another Rooivalk or ground forces via secure data link.

Cockpit Layout

Both cockpits are equipped with two main color MFD with multi-function push buttons for displaying sight images, maps or information at high resolution. There is also a secondary control and display interface unit onboard system.

Helmet Mounted Sight Display

The helmet-mounted sight display (HMSD), or TopOwl, incorporates an integrated measurement system to control the weapons. The helmet makes use of electromagnetic tracking which allows the pilot or WSO to look at a target, thereby directing the weapons on the target. The helmet has an integrated Generation IV image intensifier and FLIR capability which can be switched between with the push of a button. The TopOwl HMSD was developed by Sextant Avionique, which later merged with Thales. The pilot night vision system (PNVS) is located on the top of the nose of the Rooivalk and was developed by Cumulus, which was absorbed by Denel Optronics, and later Cassidian Optronics.

Both helmets have two monocular display modules with integrated CRT which can project Heads-Up Display (HUD) information as well as video images into the crew member’s line of sight. This allows them to retain access to their HMDS information even when using NVGs. The pilot can access real-time imagery from the PNVS while flying NOE.

HMSD symbol legend is projected onto the crewmembers visors. Courtesy of: Rooivalk – a Legend in the making

Communication Systems

The Rooivalk makes use of pre-programmable secure voice, image and data communication for enhanced battlefield communication. The communications suite consists of a Reutech Radar Systems ACR500 transceiver and AC500 controller. The suite includes two dual-frequency hopping Very High Frequency (VHF) and Ultra High Frequency (UHF) transceivers with frequency modulation (FM), amplitude modulation (AM) and digital speech processing, and one High Frequency (HF) radio with secure voice and data channels for Nap of the Earth (NOE) flying. Also included is an Identify Friend or Foe (IFF) transponder.

Main Armament

During its development, the Rooivalk’s weapons system allowed for a wide range of South African weapons. The layout and complement of armaments have remained generally the same. For this section, the initial Rooivalk ADM (1994) will be unpacked, followed by the present (2020) Rooivalk Mk1.

The Rooivalk ADM’s stub-wings each had three weapons pylons. One was on the stub-wingtips for an air to air missile and two underneath. The weapons pylons could be arranged according to mission requirements.

Under the Rooivalk ADM’s nose was a TC-20 hydraulically driven mount for a GA1 20 x 84 mm single feed Rattler cannon. It had a muzzle speed of 720 m/s and a fire rate of 600-750 rpm. Ammunition consisted of 20 x 82 mm HE-I, HEI-T, AP-HEI. Some 400 rounds were carried in an ammunition magazine located under the weapons officer’s station.

The air to air missile was a single South African supersonic passive heat-seeking V3B Kukri with proportional navigation. It has a maximum speed of 1,870 km/h, a range of 5 km, 40 g tolerance with a flight duration of 25 sec. It is the first successful helmet slaved missile in the world.

Rooivalk ADM on display in Farnborough International Airshow, United Kingdom, 1994. Visible is the V3B Kukri, HR-68 rocket launcher and 68 mm SNEB FFAR, ZT-3 Swift ATGM, external 750-litre fuel drop tank and GA-1 20 mm single feed Rattler cannon. With permission from Aviation Central.
The ZT series of ATGM missiles. ZT-3 Swift (bottom), ZT-35 Ingwe with active proximity fuse (middle) and contact probe fuse (top). Screengrab from PARATUS Magazine, April 1994.

The HR-68 rocket launcher pod carries 18 x 68 mm Societe Nouvelle des Etablissements Edgar Brandt (SNEB) unguided Folding Fin Aerial Rocket (FFAR). The rocket is powered by a 31 kg rocket motor which gives a maximum velocity of 450 m/s, and slant range is 1600 m, with an accuracy of 2 mils.

The quarto missile tube for either the ZT-3 Swift or ZT-35 Ingwe laser beam riding anti-tank guided missile (ATGM) have a 4 km and 5 km standoff range, respectively. Both are equipped with a high explosive anti-tank warhead (HEAT). The ZT-3 Swift can penetrate 650 mm of rolled homogenous armor at zero degrees and the ZT-35 Ingwe 1000 mm (with active proximity fuse). The latter is also equipped with a tandem warhead to defeat explosive reactive armor (ERA).

The Rooivalk Mk1 weapons compliment differs significantly from the ADMs. The stub-wings retained the three weapons pylons, however, the stub-wingtip pylon has moved under the wing.

For the Rooivalk Mk1, the cannon was changed to the battle-proven GI2 20 mm (mounted on the Ratel 20 Infantry Combat Vehicle), with a new chin mounting system, which includes a hydraulic-driven elevation and azimuth drive control. It has a fire rate of 720-740 rounds per minute. Its operating envelope is -110 to +110 degrees in azimuth and -55 to + 15 degrees elevation. Reaction time is 1.8 sec from selection to firing at 60 degrees traverse at -45 elevation. It has a slew rate of 90˚/sec. The cannon has two modes of operation, namely quick reaction and accurate mode. The former entails using the helmet-mounted sight for slewing the cannon on target, while the latter makes use of the nose-mounted sight.

TC-20 hydraulically driven mount with a GI2 20 mm cannon (left), ammunition feed belt with APCT rounds (right). Source Denel

The cannon rounds are kept in two sponsons on either side of the forward fuselage and fed into the cannon via a dual-feed system from inside the turret shroud. The primary ammunition used is 20 x 139 mm (HS820) High Explosive Incendiary (HE-I) and Armor Piercing Core Tracer (APCT). The HE-I, which travels at 1050 m/s, is effective up to 2 km. The APCT rounds travel at 1300 m/s and are considered effective up to 1 km and can penetrate 15 mm of RHA at 2 km. The auto-feed mechanism of the 20 mm gun allows to immediately change between the two different ammunition belts (350 rounds each) feeding into the cannon with the flip of a switch. This weapon was selected for ease of logistics. However, problems were encountered with the weapon, as the shockwave from firing would disturb the sight mirrors. This problem was fixed in the Mk1 upgrade.

The M159 rocket launcher pod carries 19×70 mm Forges Zeebrugge (FZ) unguided FFAR. The rocket is powered by a 31 kg rocket motor which gives a maximum velocity of 1250 m/s, and slant range is 9.1 km. The rocket can be fired individually, in pairs or sets of four and the articulated pylons raised or lowered for optimum trajectory. The FZ90 can carry a variety of warheads, which include High Explosive General Purpose (HEGP), Inert Practice, Flash Signature, High Explosive Armor Piercing (HEAP), Multidart and Flechette. Recently, the Rooivalk Mk1 also test-fired the FZ laser-guided rocket variant which enhances the accuracy to less than 1 m for a target at 4-5 km. Given the high cost of laser-guided ATGMs, these FZ laser-guided rockets can be a suitable compromise for a defence force on a budget not facing MBTs.

Originally designed for use on the Ratel ZT3 ICV and successfully incorporated into the Rooivalk ADM, the ZT-35 missile is too slow to be used on an aircraft. Taking 25 sec to reach 4 km exposes the Rooivalk to enemy air defence. Studies showed that exposure over 10 sec dramatically decreases a helicopter’s survivability. The ZT-35 missile has been replaced by the state-of-the-art, long-range, precision-guided 178 mm ZT-6 Mokopa (Black Mamba).

Designed and developed by Denel Dynamics in 1996, the Mokopa was initially designed as the primary anti-armor weapon for the Rooivalk. It has, however, evolved into a multi-purpose missile applicable to both conventional and asymmetrical scenarios. The missile can be fired in the traditional direct lock-on before launch (LOBL), or lock-on after launch (LOAL). With LOAL, the missile flies in the general direction of the target until it detects a designated laser beam illuminating a target within the last eight seconds of flight. The Rooivalk can also launch several Mokopa missiles in rapid-fire mode (eight seconds apart) and designate several targets using different laser codes. A remote laser targeting by another Rooivalk or ground-based designator can also be used to illuminate targets which the Mokopa will then guide towards. Rapid-fire can also be synchronised with remote lasers, each illuminating individual targets, which each Mokopa will then be allocated to and guide towards.

Mokopa and Ingwe size comparison. Source unknown

Making use of semi-active laser guidance, the Mokopa is of a modular design and can carry a penetration, fragmentation, or anti-armor warhead. Unlike the ZT3 Ingwe, the Mokopa is designed to approach a target, such as MBTs, at an angle from above, to hit where it is least armored. The tandem HEAT warhead, which can defeat ERA, is capable of penetrating 1350 mm of RHA armor at zero degrees. A High Explosives (HE) fragmentation warhead has also been developed, allowing the Mokopa to engage soft\lightly armored targets with devastating effect. Making use of a solid-fuel composite rocket motor with a slow-burning rate, it can engage targets up to 10 km away with a circular error probable of 30 cm. The first air-launched test occurred in 1999, followed by the first guided test in 2000. The Mokopa’s firing trials were completed on 21 January 2011 at the DENEL OTB test range. As a side note, the Mokopa can also is configured to make use of mmW or IIR guidance and carry multi-purpose warheads. The mmW is a true fire and forget missile which can be preprogrammed with a target’s location, to which it will guide itself after launch.

Two Mistrals in their launcher. They are carried in protective launch tubes with hinged doors which open when fired. Courtesy of: Rooivalk – a Legend in the Making

For air to air engagements, the Rooivalk Mk1 can be armed with four all aspect, fully digital Matra Mistral heat-seeking missiles. The missiles are carried on ATAM launcher pods on the outermost pylon of the stub-wings. The Mistral can be fired at targets from either the helmet-mounted sight or the main sight. The missiles have a maximum speed of 2,600 km/h, 12 g tolerance, range of 6.5 km, and carry a 3 kg HE tungsten filled warhead with detonation via laser proximity fuse.

Protection

In line with the Rooivalk design philosophy, its foremost protection lies in its agility and stealthy design. The former is achieved by a 52 per cent excess hover power for quick reaction and ability to move sideways at 93 km/h, allowing the Rooivalk to engage targets and disappear behind cover quickly. With regards to stealthy design, particular attention was paid during its development to reduce its radar, IR and noise signature. The radar signature is reduced by making use of carbon fibre and metalised fairings to shield the rotor mast and controls. The canopy surface makes use of an RF reflective material. The IR signature of the engine is reduced passively by angling the exhaust upwards into the rotor blade downwash for quicker heat dispersal. The visual signature of the fuselage only offers a 1.28 m target from the front and 4 m from the top to bottom of the rotor head. Glint is minimised by using flat and single curvature surfaces where possible. The main rotor acoustic noise is reduced by keeping the rotor tip speed low and passive measures to reduce the engine noise at the intake and exhaust. A combination of the aforementioned makes it difficult for enemies to acquire and engage the Rooivalk.

Rooivalk armoured crew seat – Sourced online

Provision was made during its design for dual redundancy of major systems, damage tolerance, and multiple load path use by avionic systems, flight and structural damage. The Rooivalk’s structure and dynamic systems have been designed to tolerate 23 mm high explosive rounds and survive direct hits from a 12.7 mm AP round and keep on working for at least 30 minutes. This allows the Rooivalk a greater chance to remain airborne and flying should it sustain damage. The self-sealing fuel tanks can also survive a direct hit from a 12.7 mm AP round without exploding. The aircrew stations are armoured against 12.7 mm AP rounds, and the seats are crashworthy, which minimizes the likelihood of injury to the crew if a crash occurs within its design performance. The Rooivalk’s crashworthy airframe is designed to withstand a sink rate of 11 m/s. and the tailwheel and landing gears designed to absorb the energy of a sink rate up to 6 m/s.

It is equipped with a Helicopter Electronic Warfare Self-Protection Suite (HEWSPS), which uses the Integrated Defensive Aids Suite (IDAS) from SAAB. The suite provides laser-warning, missile-approach-warning, as well as full multi-spectral detection capability for radar. Additionally, the suite allows for in-flight configuration against known threats.

The laser-warning system covers broadband laser frequency to detect, plot bearing and range for the display of the laser threats.

The radar warning system makes use of low Effective Radiated Power (ERP) pulse-Doppler radar detection from beyond radar detection range. Additionally, it provides ultra-broadband frequency coverage with high pulse density handling and instantaneous internal frequency measurement.

Once a threat is detected, the countermeasure system deploys chaff and flares from dispensers on either side of the rear fuselage to confuse incoming missile IR or radar lock. The system can also be operated manually or semi-automatically.

Rooivalk in Action

As a member of the UN and AU, South Africa is committed to peacekeeping missions in the DRC, Sudan and South Sudan. The eastern part of the Democratic Republic of the Congo (DRC) is characterized by mountainous terrain, which is plagued by rebel factions known for raping, pillaging and murdering civilians and aid workers alike. The UN Security Council resolution 2098 of 2013 and subsequent resolutions authorised the formation of a UN Force Intervention Brigade (FIB) in the DRC, with a peace enforcement mandate. The FIB consists of three infantry battalions, one artillery, one Special Forces and Reconnaissance Company, as well three Rooivalk MK1 and several Oryx helicopters. The countries that made up the UN FIB were South Africa, Tanzania, and Malawi.

Shortly after deploying to the DRC, the white-painted Rooivalks engaged in their first combat mission against M23 rebels at 17:00 on 4 November 2013. Making devastating use of their 70 mm rockets, the Rooivalks engaged rebel positions near Chanzu (close to the Rwandan border), while the Armed Forces of the Democratic Republic of the Congo (FARDC) conducted a ground assault against M23 positions with the assistance of artillery. The operation ended at 18:20, with the Rooivalks firing 38 and 17 rockets, respectively. Such was their physical and psychological impact and ground assault that the M23 rebels called an end to their 20-month long rebellion the very next day.

On 1 December 2015, several Rooivalks based in Goma (eastern DRC) were tasked with supporting a FIB attack on Islamist Allied Democratic Forces (IADF) guerrillas. The Rooivalk attack was preceded by Ukrainian Mi-25 Hind attack helicopters, but due to bad weather, this was somewhat ineffective against IADF ground positions. The Rooivalk, on the other hand, was unhampered and delivered accurate 70 mm rocket and 20 mm cannon fire.

The Rooivalk received high praise by various international defence analysts for its combat performance in the DRC, as it could operate in any weather condition which the Ukrainian Mi-25 Hind could not.

Typically, a Rooivalk flight mission in the DRC lasts two hours and involves intelligence, surveillance, target acquisition and reconnaissance (ISTAR) in addition to convoy and aircraft escort. While on a mission, it is armed with 550 x 20 mm rounds and 20 x 70 mm rockets. When engaging a target, the Rooivalk climbs rapidly and dives at its target firing rocket salvos and, if necessary, its 20 mm cannon. This method works best to breach the tree canopy foliage in the DRC.

While deployed to the DRC between 2013 and 2015, the three Rooivalks fired 199 70 mm rockets and 610  20 mm cannon rounds in anger. The following year saw a steep rise in rebel activity, with the Rooivalks firing 1200 70 mm rockets and 11,000 20 mm round. The majority of these combat engagements were against Allied Democratic Forces (ADF) during the last two weeks of December 2016.

Two SAAF Rooivalk Attack Helicopters serving as part of the United Nations Force Intervention Brigade, escorting a UN delegation in the Democratic Republic of the Congo, 2014. Source MONUSCO/Clara Padovan

Future Prospects

The Rooivalk must be considered in the context of the role for which it was developed, supporting deep raids by heliborne and parachute forces. Fighters would lack the time on station to give effective close support, whereas the ‘combat support helicopter’ could operate from a ‘helicopter administrative area’ closer to the objective, supplied by transport helicopters or aircraft. That set the requirement for good range, endurance and weapons load, as well as ruggedness and ease of support in an austere location. Also, logistics argued for maximum commonality with the Oryx medium helicopter.

The resulting Rooivalk has performed extremely well in the Democratic Republic of Congo, where it has flown armed reconnaissance, escort and close support for the Force Intervention Brigade. It has proved effective, including in poor weather conditions, and reliable, eliciting very positive comments from officers serving with the UN force in the DRC.

The Rooivalk is due for an upgrade, which would require the following changes to the aircraft: A new main sight, upgraded avionics, new computers and replacing some wiring with fiber. They are all practical and affordable. One Hensoldt Optronics Argos variant, for instance, can add a beam generator to the laser designator, allowing the use of both laser-guided and beam riding missiles, greatly expanding tactical capability. An air-to-air missile could be integrated, as could an advanced self-protection suite.

Its performance in the DRC has also brought interest by some other forces in a possible Mk2 variant, so the story of the Rooivalk may not end with the present fleet.

Helmoed-Römer Heitman – South African author, journalist, historian, military analyst and citizen-soldier.

Conclusion

Rooivalk is a highly sophisticated digital aircraft. The investment in digital-based systems provides a weapon system that is capable of achieving ultra-high assurance levels of mission accomplishment in a most demanding operational environment. Furthermore, the hazards of this environment, such as adverse weather, terrain and darkness; as well as the threats posed by the enemy, are significantly reduced because of very effective electronic enhancement. There need be no doubt that the percentage of the purchase price of Rooivalk that is attributable to avionics and electronics is money seriously well spent.

Robert Paul Jonkers – Programme Manager for the Rooivalk (1999-2004)

Videos

Rooivalk Weapons Demo https://www.youtube.com/watch?v=9_vn0gSXaKU

Rooivalk Combat Support Helicopter – SAAF 16 Squadron – Live onboard Cameras https://www.youtube.com/watch?v=8_m-S9PW5vY

Specifications

ROOIVALK CSH MK1 SPECIFICATIONS

(Typical mission loadout)

Crew 2 Fuel capacity (kg) (3 x tanks) 480
Mission weight (t) 7.5 Max. range (km) 740
Power-to-weight ratio (shp/t) 246 Engine power output (shp) 1845
Length (m) 16.39 Cannon calibre (mm) 20
Width (m) 6.95 Rockets calibre (mm) 70
Height (m) 5.19 Air to ground missiles calibre (mm) 127
Ascend rate (m/s) 11 Air to air missiles calibre (mm) 90
Max. flight altitude (ft) 20,000 Ammunition of Cannon 700
Hover over ground effect (m) 5,029 Rockets (2 x pods) 38
Cruising speed (km/h) 278 Air to ground missiles (2 x quarto rails) 8
Max. speed (km/h) 309 Air to air missiles (2 x dual pods) 4

Gallery

AH-2A – No. 678 AFB-Langebaanweg Dec 2017 – By Ed Jackson – artbyedo.com
AH-2A – No. 676 AFB-Durban Feb 2017 – By Ed Jackson – artbyedo.com

Special Thanks

The author would like to acknowledge and thank several individuals. Rob Jonkers, former Programme Manager for the Rooivalk (1999-2004), for doing quality control of the article content and providing permission to source from his book Rooivalk – a legend in the making. Also Justin Cronjé from defenceWeb, which is Africa’s leading defense news portal, for making some of their resources available. Helmoed-Römer Heitman for his contribution on the Rooivalk’s possible future.

Sources

 

 

Sikorsky S-70C-2 Black Hawk in Communist Chinese Service

PRC flag People’s Republic of China (1984)
Utility Helicopter – 24 Operated

The Sikorsky Black Hawk family is one of the most well-known helicopters of recent history. In its dozens of guises, it serves over 20 militaries worldwide. One of the lesser known operators is the People’s Republic of China. Initially purchased to be operated in the mountainous terrain of Tibet and Xinjiang, the Black Hawk eventually found itself as an aid relief helicopter in the 2008 and 2013 earthquakes in Sichuan and an inspiration for the design of the Harbin Z-20 helicopter.

History

S-70C-2 in combat excercises [dser.com]
The harsh geographic characteristics of Tibet and Xinjiang undoubtedly presented many tough problems to the People’s Liberation Army (PLA). The extreme altitudes of the Tibetan and Xinjiang plateaus make the duties of border troop outposts quite difficult, with Tibet being especially problematic. The Tibetan border alone spans nearly 3,728 mi / 6,000 km, with guard posts on mountains reaching over 13,123 ft / 4,000 m. The highest guardpost is the Shenxianwan (神仙湾) post at 17,650 ft / 5,380 m altitude. At these extreme altitudes the temperature is quite low with snow covering the mountains all year around, and the air is also oxygen deficient. All these factors combined make patrols and resupplying quite difficult for the border troops. Helicopters are the only viable option for resupplying missions as there are nearly no airstrips or adequate roads. The oxygen scarcity prevents helicopter engines from working to their full capacity, as well as reducing the rotor efficiency. This means that flying a helicopter up to that altitude is risky and difficult. Even if the helicopter can safely arrive, the amount of supplies that can be transported is severely limited and it would require several trips to fully resupply a base. In order to find a solution for this problem, China began to look into the international market for a high performing utility helicopter capable of operating at high altitudes and replacing the aging Soviet Mi-8 they were using for transport duties. Adopting the principle of “comparing three products and buying the best” (货比三家,择优选购), China chose three models of helicopters from various Western companies to compete for their business. The American Bell 214ST, Sikorsky S-70 Black Hawk and French AS332 Eurocopter were chosen as potential candidates and examples of these helicopters were promptly sent to Lhasa for flight trials in December of 1983.

S-70C-2 preparing for takeoff [seesaawiki.jp]
The flight tests were conducted on an airfield at an altitude of approximately 5,600 ft / 1,600 m and had all three helicopters fly to higher mountains. Upon reaching approximately 9,840 ft / 3,000 m, it was discovered that the power of all these helicopters dropped noticeably and the engines were not able to deliver sufficient amounts of thrust and the helicopters were unable to successfully complete the test flight. After three months of research, Sikorsky’s technicians were able to successfully address most of the issues and flight tests for the Black Hawk were continued. The improved Black Hawk was able to fly over the Tanggula Mountains at an altitude of over 17,060 ft / 5,200 m and land in the nearby Ali region. After numerous thorough examinations, the Black Hawk was ultimately crowned as champion and determined to be best suited for the Tibetan and Xinjiang environment. In July of 1984, the Chinese government officially placed an order for 24 unarmed S-70C-2 Black Hawk models, which would be specially built for China. They featured high performing General Electric T700-701A engines for high altitude flights and a nose-mounted weather radar. The first batch of Blackhawks would arrive in November of the same year, designated as civilian helicopters. The transaction cost China an approximated total of 140 million USD.

S-70C-2 LH92204 participates in an aid relief operation [Sina News]
Despite officially being classified as civilian helicopters, the S-70C-2 was used in a military capacity during their service with the People’s Republic of China. Initially assigned to the People’s Liberation Army Air Force (PLAAF) in 1986, the Blackhawks were later reallocated to the PLA’s air branch. In Chinese service, the Black Hawk would mostly be assigned to the Tibetan plateaus, where they resupplied and transported border troops. During the 1987 border skirmish with India, the Blackhawks were extensively used for tactical troop transport and supply runs in the Indo-Tibetan border region. The S-70C-2 was able to carry up to 8000 lbs / 3630 kg of equipment, 12 or 14 people in normal situations , and up to 19 people in emergency situations. Unfortunately for the Chinese, support and spare parts from Sikorsky would come to an abrupt end after the 1989 Tiananmen Square massacre. The result of this massacre greatly impacted Sino-American relations and future sales of military hardware were prohibited. It seems that Sikorsky made an attempt to reestablish relations with the Chinese in 1998 by asking the government to allow the sale of replacement engines and parts to the Chinese, arguing that the parts should no longer be considered military hardware. This request, if ever made, was rejected. It would appear that only 21 of the 24 Blackhawks purchased were in service after 2000. Three Blackhawks were supposedly written off during service, probably due to piloting error or equipment malfunctions. Numerous Blackhawks were deployed during the 2008 and 2013 earthquakes in Sichuan, China to administer aid relief, alongside numerous Soviet-era helicopters such as the Mi-8. The Blackhawks are still in service with the Chinese to this day, but will most likely be replaced by the Harbin Z-20.

China’s “Indigenous” Black Hawk

Harbin Z-20 [chinese-military-aviation.blogspot.com]
When taking in account of China’s long history of reverse engineering or copying technology from other countries, it should be no surprise that the Harbin Aircraft Manufacturing Company’s (HAMC) latest Z-20 (直-20, or Zhi-20) helicopter bears a striking resemblance to the Blackhawks. Believed to have been in development since 2006, the Z-20 finally took to the skies on December 23rd of 2013. Contemporary sources seem to suggest that the Z-20 possesses superior characteristics to the Black Hawk due to the refined design, but this has yet to be confirmed. As the Z-20 has only recently entered service and is still kept in relative secrecy. One can only speculate about its capabilities.

Variants Operated

  • S-70C-2 – The People’s Republic of China operated 24 examples of the S-70C-2 which were specially built for them by Sikorsky. This variant featured a nose-mounted weather radar, improved General Electric T700-701A engines for high altitude flights and various other improvements to the fuselage.

 Gallery

Illustrations by Ed Jackson www.artbyedo.com

Sikorsky S-70C-2 – LH92207
Sikorsky S-70C-2 – LH92210
S-70C-2 Hovering (Unknown source)
Detailed closeup of cockpit exterior (afwing.info)

S-70C-2 LH92206 transports a jeep during a military exercise [Sina News]
An unidentified S-70C-2 Black Hawk evacuates civilians in the Tibetan region. [Encyclopedia of Chinese Aircraft]
An unfortunate incident involving a unidentified S-70C-2 [Army Star]

Sources