High-Speed Helicopter Revolution: Sikorsky's Dual-Rotor Design



• Dual Rotors: Single-rotor helicopters tend to roll at high speeds as their retreating blades lose lift. The X2’s opposed rotors create equal amounts of lift on both sides.
• Rear Propulsor: For maximum thrust, engine power is split between the main rotor and an aft propulsor.

Helicopters have always had a hard time going fast. The forward motion of the chopper adds airspeed to advancing blades, while simultaneously reducing the speed of retreating blades. So, at high speeds one blade risks going supersonic as it gains lift, while a blade on the other side teeters on the edge of a stall.

Hoping to overcome that problem, Sikorsky Aircraft is testing a helicopter that uses two sets of blades that spin in opposite directions, balancing out the loss of lift experienced by the retreating blades on each side. The system is part of a suite of advances that Sikorsky Aircraft calls X2 Technology, which should allow the test vehicle to achieve nearly twice the speed of a conventional helicopter. "We're designing for a cruise speed of 288 mph," says program manager Peter Grant, "with dash speeds much greater than that." Theoretically, an X2-equipped chopper could hit 334 mph.

The 30-ft.-long X2 Technology Demonstrator is a research platform, so it won't directly spawn any production helicopters. Whether the technology eventually winds up in everything from gunships to civilian transports, such as Sikorsky's "Commercial Intermediate" concept (illustrated above), may depend on how well the testbed flies. At press time Sikorsky had yet to set a flight testing date.

Pozdravlja ih ruski Kamov 

kad smo več kod kamova evo nešto od jučer.....

Izmislili su toplu vodu, mislim ovo je neozbiljno tvrditi da je revolucionaran dizajn, jedina novost je pogonski rotor na repnom delu. Posto smo vec spomenuli Ka-50 evo i jedna novost:
Izvor: www.kommersant.com

@ramon23 lepo je čuti ovo...............

Pa i taj pogonski rep je vec ispitan negde pedesetih...  Ma dobro ajde, nek se nesto radi, da ne bude da samo kritikujemo 

eh, to čudo od helikoptera, Kamov... čuo sam da će ga mnoge afričke i bliskoistočne zemlje uzeti.

Gde si cuo, daj izvor da i mi citamo...

to mi je pričao jedan ortak, ali konkurencija je jaka, tu je JAR, SAD, Italija, Nemačka i Francuska, znači još će se čekati na operativnu upotrebu u nekim drugim državama.

Mislim da se Ka-50/52 nece nuditi stranim zemljama, jer ce biti radjen u malim serijama za potrebe specijalnih jedinica Rusije (kao sto i pise u tekstu koji je postavio @ramon23).
Inace su amerikanci  jos ranije eksperimentisali sa ovom koncepcijom helikoptera: http://en.wikipedia.org/wiki/AH-56_Cheyenne

Nudice se, zasto se ne bi nudili, u textu samo stoji da su u rusiji ispusili na tenderu za glavni borbeni helikopter ruskog vazduhoplovstva, ali su zato dobili ugovor za specijalce. To samo znaci da ce se sada jos zesce utrkivati na stranom trzistu kako bi povratili sredstva ulozena u razvoj. Bili su pre par godina na tenderu za Turski borbeni helikopter, pa su na zahtev turaka modifikovali ga u dvosedu varijantu, ali je to propalo. Isto tako ce nuditi i na drugim trzistima, samo je pitanje koliko ce biti uspesni.

Po Latinskoj Americi će plasirati Mil dok bi Kamov došao samo u slučaju mornaričkih varijanti(KA-27, KA-29, KA-31, KA-32).
Tu Mil ima baš optimistične planove, strani mediji kažu oko 400(ne znam za koliki period) . Dobro su se pokazali Hugu Čavezu.
Ako nađem link, izbaciću ga.

@ramon23  Što je bilo sa KA-50-2 Erdogan(mislim da je to bila oznaka modela ponuđenog Turcima)?
Nisam siguran da li je on ikad poletio. Jer na slikama se može naći jedino maketa, sa kokpitom sličnim kao kod Apača.
 
 

KA-50-2 Erdogan.....ovo je verzija KA-50 koja je rađena između Izraela te Rusije....da bijo je rađen za potrebe Turske....zatim je Turska izabrala kobre jer bilo nekakvih problema kod transfera tehnologije za KA-50-2 bar tako kažu....

...........

Kamov zakon heli 

Ka-50 Black Shark

Any information about this helicopter was strictly secret in 70's and 80's. American intelligence services had problems to get any information about its development. The situation has rapidly changed a few years ago. Everybody could see the brand new Kamov helicopter on Paris Airshow 92' for the first time.

Helicopters from the Kamov Company have traditionally been given NATO codenames beginning with the letter "H", and the Ka-50 Black Shark helicopter carries the NATO codename Hokum A, Hokum B being the two-seat version, Ka-52. Ka-50 is also known as Werewolf. The Ka-50 Black Shark entered service in the Russian Army during 1995 and is in full production at the Sazykin Aviation Company Progress based in Arseniev maritime Territory, Russia. It is a high performance combat helicopter with day and night capability, high survivability and fire power to defeat air targets and heavily armoured tanks armed with air defence weapons.


Ka-50-2 Erdogan

Ka-50-2 Erdogan

This type developed with cooperation between Russia and Izrael is know as Ka-50-2 Erdogan. It was designed to meet conditions annonced by Turkey Air Force. Erdogan is third the most modern two-seat tandem modification of Kamov Ka-50 with izrael avionics. Some weapons are of Izreal origin as well.
Ka-52 Alligator

The success of any combat operation to support ground forces on the battlefield depends to a large extent on the joint combat actions of group combat helicopters. A group commander flying in a combat formation is responsible for control over subordinate helicopters. His helicopter should be fitted with more sophisticated equipment compared to the rest of the group to make him see better targets on the battlefield and be able to ensure target designation and distribution, provide for constant control over group combat helicopters and maintain communications with a ground command post. The scope of tasks assigned to the commander frees him from helicopter piloting. Consequently, he should fly in a two-seat flying combat vehicle.

The Ka-52, designated Alligator, multi-role all-weather combat helicopter, is intended for this purpose as a two-seat modification of the Ka-50 combat helicopter. Pilots accommodated side-by-side in one cockpit can fly this helicopter and handle all on-board systems. The Alligator retained all combat capabilities of its predecessor, including the whole array of weaponry. It is outfitted with a multifunctional on-board integrated electronic flight, navigation and weapon control system. Its passive/active observation/search and sighting systems ensure target search and their attack day/night in any weather conditions. The Sextant Avionic of France and Thomson company take part in creation of this helicopter. The Ka-52 Alligator is 85 percent identical to the Ka-50 base helicopter in terms of its airframe and main systems. Pilots escape via an ejection system. The Ka-52 Alligator can also be used as a trainer. Pilot accommodation and the availability of new multifunctional equipment system led to an increase in the weight of the empty helicopter and a certain deterioration in flight performance, compared to the Ka-50. However, it did not affect the integrated quality of this flying machine as a whole.

Externally, the Ka-52 combat helicopter differs from its predecessor in the front part of the fuselage, shape of the cockpit and arrangement of round-the-clock observation/search and sighting systems. Pilots are rigged with pressurized helmets fitted with built-in displays to provide for required flight and sighting data. The Ka-50 and Ka-52 helicopters feature interchangeability, thereby reducing costs for series production and joint operation in combat units.

Naturally, Alligator is more expensive than Black Shark. However, this is attributable to payments for the capability to perform combat missions on higher and more efficient levels. The advent of Ka-52 does not mean its automatic substitution by the Ka-50. They can be used more effectively in the interests of the ground forces, owing to their optimal joint employment in groupings. A similar approach is also adopted by the U.S. army aviation. The more costly and sophisticated AH-64D and AH-64D LongBow helicopter versions do not replace, but instead reinforce the AH-64A Apache helicopter groupings, thereby increasing their efficiency.

In the near future the Ka-52 will be subjected to tests. The Kamov company and its foreign partners are convinced of the successful results of the tests that will enable the Ka-52 helicopter to occupy a leading position in its class. It is up to foreign buyers to decide whether to choose the Ka-50 or the Ka-52 or a hybrid to meet their requirements.

Horni obr. kokpit Ka-50, dolni je Ka-52
Development

The development of this helicopter had started in year 1978 according to specifications annonced by Soviet Ministry of Defense in 1977. Codename V-80 was used till 1992, when the name Ka-50 was given to new Kamov helicopter. Kamov Ka-50 was designed for usage over the land, not for naval operations as almost all Kamov helicopters before (e.g. Ka-25 or Ka-27). The first model 1:1 was showed to Soviet Military Chiefs in May 1980. In two years on 17 June 1982 the first flight was accomplished. Kamov Ka-50 had serious competitor. Mil worked at the same time on brand new Mil Mi-28 (known as Havoc now). Both aimed to win the tender for new helicopter. When testing Ka-50 and Mi-28 helicopters, Ka-50 seemed to be better. Mil wished tests of helicopters repeated. Three times both types were tested, but Ka-50 was better in every test. Soviet Ministry of Defense decided to continue development of both competitors.

The development of the Ka-50 Black Shark and AH-64A Apache combat helicopters aimed to redress this disparity and make the helicopters able to defeat tanks armed with air defense weapons. The Ka-50 combat helicopter can be used to defeat targets on the battlefield within wide ranges of launching high-precision supersonic antitank missile systems, including launches from more than a 6-km range within a stand-off zone of air defense artillery and air defense missile systems. The Ka-50 combat helicopter is intended to defeat modern armored and mechanized materiel, air targets and hostile manpower. This co-axial helicopter features a high flight performance and ease of piloting via automated flight devices. It can successfully execute combat missions day/night owing to high survivability under hostile fire, powerful armament and comfortable pilot's cockpit. The helicopter was tested in simulated combat conditions. . The Ka-50 helicopter is unrivalled in the world in terms of the 'cost-efficiency' criteria. In 1995 the Ka-50 combat helicopter entered service and is now series produced at Progress Arsenyevsk-based aviation complex.
Avionics

Flight systems include inertial navigation system (INS), autopilot and head-up display (HUD). HUD of Ka-50 is the same as in Mig-29. Sensors include FLIR (forward-looking infrared) and terrain-following radar.
Engines

The Ka-50 is powered by two TV3-117VMA turboshafts engines each providing 2,200 horsepower. The power plant is fitted with deflectors and separators to prevent dust ingestion in the air intakes which protects the engines from wear when taking off from unprepared sites. The engines are placed on either side of the fuselage to enhance the combat survivability. The helicopter also has an auxiliary power unit (APU) for selfcontained operation.
Weapon systems

The Ka-50 helicopter is fitted with observation and sighting systems together with navigation, communication and other systems to enable one crew-member to pilot and engage hostile forces in combat. A combination of various armaments to a maximum combat weapon load of 2 tons are selected according to the combat mission, including anti-tank missiles, unguided aerial rockets of different calibres, air-to-air missiles, guns, bombs and other weapons.

The helicopter has small mid-mounted wings fitted with four underwing suspension units and wingtip countermeasures pods. Up to 12 Vichr supersonic antitank missiles with unified warheads against ground armoured and air targets can be mounted on the helicopter's two underwing external stores. There can be also attached stores with 23-mm guns or additional fuel tanks.

The missiles are automatically guided to the selected air or ground target using laser beam riding and feature a high degree of jam resistance. The Vichr missile has a target hit probability close to one, against a tank at a range of up to 8 km. The kill probability is also rated very highly with the capability of penetrating all types of armour including active armour up to 900 mm thick.

The Ka-50 is armed with a 2A42 quick-firing 30-mm gun which has an unrestricted azimuth and elevation range mounting for use against airborne or ground targets. The gun is mounted near the centre of gravity of the helicopter for consistent accuracy. The gun is equipped with 460 rounds of ammunition, two types being carried, high-fragmentation and explosive incendiary rounds and armour-piercing rounds. The pilot selects the type of ammunition in flight. The weight of the ammunition is 0.39 kg each round, the muzzle velocity is 980 m/s and the range is up to 4 km. The gun provides an angular firing accuracy of 2 to 4 mrad.
Co-axial rotors

The coaxial rotor design provides a hovering ceiling of 4,000 metres and vertical rate of climb of 10 metres per second at an altitude of 2,500 metres. The rotor blades are made from polymer materials. The hingeless main rotor head requires no lubrication.

The coaxial-rotor configuration results in moments of inertia values relative to vertical and lateral axes being between 1.5 to 2 times less than the values found in conventionally designed combat single rotor helicopters with tailrotors. Absence of the tail rotor enables the helicopter to perform flat turns within the entire flight speed range. A maximum vertical g-load of 3.5 combined with low moments of inertia give the Ka-50 a high level of agility and manoeuvrability.
Survivability

Two separately mounted engines at a maximum distance reduce the probability of their simultaneous damage. The powerplant has an operational life of 30 minutes without oil, giving the pilot the opportunity to land in a safe location in the event that the oil system is damaged in combat. The helicopter also has duplicated and stand-by hydraulic and power systems and main control circuits.

Extensive all-round armour installed in the cockpit protects the pilot against 12.7 mm armour piercing bullets and 23 mm projectile fragments. The rotor blades are rated to withstand several hits of ground-based automatic weapons providing the capability of safe flight completion after sustaining impact.

Protection of fuel tanks against explosion hazards and fuel leakage is provided by porous fuel tank fillers and fuel tank self-sealing covers, and a comprehensive fire extinguishing system is installed. Engine exhaust heat screens reduce the thermal signature of the helicopter and flare dispensers protect the helicopter against heatseeking missiles.

The Ka-50 is the world's first operational helicopter with a rescue ejection system, which allows pilot to escape at all altitudes and speeds. The K-37-800 Rocket Assisted Ejection System is manufactured by the Zvezda Research and Production Enterprise Joint Stock Company in the Moscow Region. The seat operates by pulling the pilot from the helicopter cabin using a solid-propellant rocket motor. The system comprises the seat, a control unit and a pullout rocket motor. The seat is fitted with a survival pack containing an NAZ-7M survival kit, a life raft and a PS-37A parachute system. The seat provides safe forced emergency escape from helicopters in the speed range 0 to 350 km/hour and at altitude 0 to 6,000 metres. The seat also provides safe ejection during inverted flight (at speeds 0 to 330 km/h with zero vertical velocity) at a minimum altitude of 90 metres. Pilot is ejected in max. six second.

Ka-50 is fitted with radar warning receiver, electronic warfare system and chaff and flare dispenser UV-26.
Maintenance

Built in test and diagnostics equipment ensures fast maintenance turnaround time. Under operational conditions the helicopter has a 12-day combat availability with minimum maintenance during off-base deployment.

bogami bilo bi pravo čudo da Srpsko V i PVO nekupi najmanje5 komada ako nedođe do para. nego jeste li čuli da je hrvatska zabranila animiranu reklamu za koka Kolu jer na kraju proleće Gazela iz koje iskaču specijalci sa oznakama JRV.