Eko Triyanggono: Attack Helicopter

Showing posts with label Attack Helicopter. Show all posts

Northrop Grumman MQ-8 Fire Scout

The Northrop Grumman MQ-8 Fire Scout is an unmanned autonomous helicopter developed by Northrop Grumman for use by the United States Armed Forces. The Fire Scout is designed to provide reconnaissance, situational awareness, and precision targeting support for ground, air and sea forces. The initial RQ-8A version was based on the Schweizer 330, while the enhanced MQ-8B was derived from the Schweizer 333.

Design and Development

RQ-8A

As the US Navy was withdrawing its RQ-2 Pioneers from service, it began to seek a second generation UAV. The Navy requirement specified a vertical takeoff & landing (VTOL) aircraft, with a payload capacity of 90 kilograms (200 pounds), a range of 125 miles (200 km), an endurance on station of three hours at an altitude of 20,000 ft (6 km), and the ability to land on a ship in a 46 km/h (29 mph) wind. The UAV was to fly 190 hours before planned maintenance.

There were three finalists in the competition, which was designated "VTOL-UAV" or "VTUAV". Bell, Sikorsky, and a collaboration of Teledyne Ryan and Schweizer Aircraft submitted designs. The Ryan-Schweizer UAV was selected as the winner in the spring of 2000. The RQ-8A Fire Scout, as it was named, was a derivative of the Schweizer three-passenger, turbine powered 330SP helicopter, with a new fuselage, new fuel system, and UAV electronics and sensors. The initial prototype of the Fire Scout was piloted in initial tests, flying autonomously for the first time in January 2000. The Rolls-Royce 250-C20 turbine engine ran on JP-8 and JP-5 jet fuel (the latter of which has a lower flashpoint and is considered safe for shipboard storage and use).

The Fire Scout was to be fitted with a sensor ball turret that carries electro-optic and infrared cameras, and a laser range finder. It was to be controlled over a data link derived from the Northrop Grumman RQ-4 Global Hawk UAV, operating over a line of sight to a distance of 172 miles (280 km). The control system was to be fitted onto a ship, or could be carried on a Humvee light vehicle for US Marine service.

MQ-8B

Although progress on the project had been regarded as satisfactory, the Navy decided the Fire Scout didn't meet their needs after all, and cut funding for production in December 2001. However, the development program continued, and Northrop Grumman pitched a range of improved configurations to anyone who was interested. As it turned out, the U.S. Army was very interested, awarding a contract for seven improved RQ-8B evaluation machines in late 2003. In 2006, it was redesignated MQ-8B.

The MQ-8B features a four-blade main rotor, in contrast to the larger-diameter three-blade rotor of the RQ-8A, to reduce noise and improve lift capacity and performance. The four-blade rotor had already been evaluated on Fire Scout prototypes. They boost gross takeoff weight by 500 pounds to 3,150 pounds (by 225 kg to 1,430 kg), with payloads of up to 700 pounds (320 kg) for short-range missions.

The MQ-8B is fitted with stub wings which serve both an aerodynamic purpose as well as an armament carriage location. Weapons to be carried include Hellfire missiles, Viper Strike laser-guided glide weapons, and, in particular, pods carrying the "Advanced Precision Kill Weapon System (APKWS)", a laser-guided 70 millimeter (2.75 inch) folding-fin rocket, which the Army saw as ideal for the modern battlefield. The Army was also interested in using the Fire Scout to carry up to 200 pounds (90 kg) of emergency supplies to troops in the field.

The MQ-8B is being modified to permit rapid swap out of payload configurations. The current sensor configuration of a day/night turret with a laser target designator will remain an option. Alternate sensor payloads in consideration include a TSAR with Moving Target Indicator (MTI) capability, a multispectral sensor, a SIGINT module, the Target Acquisition Minefield Detection System (ASTAMIDS), and the Tactical Common Data Link (TCDL). The Army wanted the Fire Scout to operate as an element of an integrated ground sensor network as well.

Production of the flight test airframes was initiated in April 2006 at the Northrop Grumman Unmanned Systems production plant in Moss Point, Mississippi. The Navy approved low-rate initial production. The first flight of the MQ-8B took place on 18 December 2006 at Naval Air Station Patuxent River. The Army interest revived Navy interest in the program, with the Navy ordering eight Sea Scout MQ-8B derivatives for evaluation. In January 2010, the Army terminated its involvement with the Fire Scout, contending that the RQ-7 Shadow UAV could meet the Army's needs.

The MQ-8B complements the manned aviation detachments onboard Air Capable ships and is deployed along with either an SH-60B HSL/HSM detachment or a MH-60S HSC detachment. With the planned addition of RADAR, AIS, and weapons, the MQ-8B will provide many of the capabilities currently provided by the SH-60B. It will give the ship and embarked air detachment greater flexibility in meeting mission demands, and will free manned aircraft for those missions.

Northrop Grumman has started work outfitting the MQ-8B with a weapons system. The Advanced Precision Kill Weapon System laser-guided 70 mm rocket. The corporation will develop and deliver the equipment needed to control the weapons system under a $17 million contract awarded to the company 23 September 2011 by Naval Air Systems Command. Final delivery of an operational system is expected by March 2013.

On 30 December 2012, the Navy issued an urgent order to install RDR-1700 maritime-surveillance radars on nine MQ-8B Fire Scouts. Installation should be completed by the end of 2013. The system consists of the radar, modified MQ-8B radome, and interfaces into the helicopter UAV and its control station. The radar weighs 71 lb and will be mounted underneath the helicopter to give 360-degree coverage. It is an X-band synthetic aperture radar that can show objects in a detailed way. Detailed range is out to 25 km (16 mi), with a max range of 80 km (50 mi). The RDR-1700 can see through clouds and sandstorms and can be used for terrain mapping or for weather detection. It can track 20 air or surface targets and can use a target-marker to determine the range, bearing, and velocity of a target. MQ-8B UAVs with the radar could be useful in the Persian Gulf to track small Iranian speed boats, or the Gulf of Aden to locate Somali pirates.

MQ-8C Fire-X

On 3 May 2010, Northrop announced plans to fly a Bell 407 helicopter modified with autonomous controls from the MQ-8B. Named Fire-X, it was designed to demonstrate an unmanned cargo resupply capability to the US Navy. The unmanned Fire-X completed its first flight at Yuma Proving Ground in Arizona on 20 December 2010. On 23 April 2012, Northrop received a $262.3 million contract from the Navy to develop and build the newly designated MQ-8C version of the Fire Scout. The contract calls for Northrop to build and test two developmental aircraft over the next 26 months. The company is also contracted to build six low-rate production aircraft at the same time. The Navy wants 28 MQ-8Cs for naval special operations forces. The MQ-8C weighs 2.7 tons, has a 1,000 lb payload, and has an endurance of up to 24 hours. It can be armed with AGM-175 Griffin missiles and APKWS II guided 70 mm rockets that the MQ-8B can carry, as well as heavier AGM-114 Hellfire missiles. The MQ-8C is expected to enter service in 2014. In March 2013, the Navy incorporated the Rolls-Royce 250-C47E into the MQ-8C. The new engine has a 5% increase in "hot and high" power, 2% reduced fuel consumption, 8% increase in rated takeoff power to 700 shaft horsepower, and better reliability.

Operational History

In January 2006, an RQ-8A Fire Scout landed aboard the U.S. Navy warship USS Nashville while it was steaming off the coast of Maryland near the Patuxent River. This marked the first time an unmanned helicopter has landed autonomously aboard a moving U.S. Navy ship without a pilot controlling the aircraft. The USS Nashville, which is an amphibious transport ship, was maneuvering as fast as 17 mph (27 km/h) in the tests.

The flight test program is underway. Production aircraft will eventually be deployed on the Navy's Littoral Combat Ships. In February 2008, the U.S. Navy announced that they would integrate the MQ-8B Fire Scout VTUAV onto another air-capable ship before it reaches the Littoral Combat Ship (LCS)

The Fire Scout is a key enabler for LCS and significantly contributes to its designated warfare mission areas of anti-submarine warfare, surface warfare and mine warfare. The modular nature of the ship to accomplish the designated mission is complemented by the Fire Scout and its modular mission payload capability. However, due to changes in the LCS development schedule, the Navy conducted the Fire Scout Operational Evaluation (OpEval) aboard USS McInerney (FFG-8). This will provide the fleet with unmanned aerial system support as soon as possible. The Fire Scout first embarked aboard the guided-missile frigate USS McInerney, an Oliver Hazard Perry-class frigate, while in port for operational fit checks and ship integration testing on December 10, 2008. The Fire Scout was slated to deploy aboard USS McInerney during its next counter-narcotics trafficking deployment later in 2009.

According to the current schedule, the Navy conducted Technical Evaluation on the Fire Scout on the FFG-8 in the fall 2008 and Operational Evaluation in the summer 2009. The Fire Scout was to reach Initial Operating Capability soon after the evaluation. The Navy will continue to support LCS Initial Operational Test and Evaluation (IOT&E) efforts in fiscal year 2011.

Flight tests took place 4–8 May 2009 off the coast of Mayport, Fla. The U.S. Navy Fire Scout completed test flights in areas of shipboard deck motion and wind envelope expansion and landings including the use of the grid and harpoon system. During the five days of testing, the ship/aircraft team compiled 19 flight hours during 12 flights, which included 54 landings, 37 of which were into the NATO standard grid.

In September 2009, the Navy announced the first deployment of the MQ-8B aboard McInerney. On 3 April 2010, an MQ-8 from McInerney detected a "go-fast" open speedboat and a support vessel engaged in smuggling cocaine in the Eastern Pacific, allowing the ship to confiscate 60 kg of cocaine and detain a number of suspects. On 2 August 2010 an MQ-8 became unresponsive to commands during testing and entered restricted airspace around Washington, D.C. In May 2011, three MQ-8s were deployed to northern Afghanistan for intelligence, surveillance, and reconnaissance (ISR), a mission which has been extended another year. On 21 June 2011, a MQ-8 operating from USS Halyburton (FFG-40) as part of Operation Unified Protector was shot down over Libya during a surveillance and reconnaissance mission. Aboard the Halyburton, the Fire Scouts were flown and maintained by the ship's SH-60 detachment, HSL-42.

The U.S. Navy briefly grounded the MQ-8B Fire Scout after two of the aircraft crashed overseas within a week. In the first incident, the Navy said a Fire Scout crashed off the coast of Africa on 30 March after it was unable to land on the US Navy Oliver Hazard Perry-class frigate USS Simpson (FFG-56) at the end of a surveillance mission. On 6 April 2012, another Fire Scout crashed in Afghanistan. An investigation into the crash in Afghanistan determined the cause was a faulty navigation system. The cause of the crash near the USS Simpson (FFG-56) remains less clear, so the result was tougher maintenance procedures put in place to prevent a faulty copter from going on-mission. The Fire Scout was back flying over Afghanistan by May, and returned to sea-based ISR "anti-piracy" operations by August.

The U.S. Navy has continued to deploy the MQ-8B to the African AOR with deployments in USS Klakring (FFG 42) and USS Robert G. Bradley (FFG 49). In each of the deployments the UAV has exceeded 500 flight hours, while providing critical ISR coverage for AFRICOM and 6th Fleet.

General characteristics

Crew	0
Payload	600 lb (272 kg)
Length	23.95 ft (7.3 m)
Rotor diameter	27.5 ft (8.4 m)
Height	9.71 ft (2.9m)
Empty weight	2,073 lb (940.3 kg)
Max. Take off weight	3,150 lb (1,430 kg)
Powerplant	1 x Rolls-Royce 250, 313 kW (420 hp)

Performance

Maximum speed	115 knots (213 km/h)+
Cruise speed	110 knots (200 km/h)
Combat radius	110 nmi (203.7 km) with 5+ hours on station
Endurace	8 hours
Service ceiling	20,000 ft (6,100 m)

DISCLAIMER: The material content provided on this page is generated by another sources and consequently features user-generated content. While we do our best to stop offensive material appearing, ekotriyanggono.com cannot be held responsible for all of the material that may be displayed on this page. If you object to any article or picture, please leave us a comment in this page.

AH-1Z Viper

The Bell AH-1Z Viper is a twin-engine attack helicopter based on the AH-1W SuperCobra, that was developed for the United States Marine Corps. The AH-1Z features a four-blade, bearingless, composite main rotor system, uprated transmission, and a new target sighting system. The AH-1Z is part of the H-1 upgrade program. It is also called "Zulu Cobra" in reference to its variant letter.

Development

Background

Aspects of the AH-1Z date back to the Bell 249 in 1979, which was basically an AH-1S equipped with the four-blade main rotor system from the Bell 412. This helicopter demonstrated Bell's Cobra II design at the Farnborough Airshow in 1980. The Cobra II was to be equipped with Hellfire missiles, a new targeting system and improved engines. Later came the Cobra 2000 proposal which included General Electric T700 engines and a four-blade rotor. This design drew interest from the US Marine Corps, but funding was not available. In 1993, Bell proposed an AH-1W-based version for the UK's new attack helicopter program. The derivative design, named CobraVenom, featured a modern digital cockpit and could carry TOWs, Hellfire or Brimstone missiles. The CobraVenom design was altered in 1995 by changing to a four-blade rotor system. The design lost to the AH-64D later that year however.

H-1 Upgrade Program

In 1996, the USMC launched the H-1 upgrade program by signing a contract with Bell Helicopter for upgrading 180 AH-1Ws into AH-1Zs and upgrading 100 UH-1Ns into UH-1Ys. The H-1 program created completely modernized attack and utility helicopters with considerable design commonality to reduce operating costs. The AH-1Z and UH-1Y share a common tail boom, engines, rotor system, drive train, avionics architecture, software, controls and displays for over 84% identical components.

Bell participated in a joint Bell-Government integrated test team during the engineering manufacturing development (EMD) phase of the H-1 program. The AH-1Z program progressed slowly from 1996 to 2003 largely as a research and development operation. The existing two-blade semi-rigid, teetering rotor system is being replaced with a four-blade, hingeless, bearingless rotor system. The four-blade configuration provides improvements in flight characteristics including increased flight envelope, maximum speed, vertical rate-of-climb, payload and reduced rotor vibration level.

The AH-1Z first flew on 8 December 2000. Bell delivered three prototype aircraft to Naval Air Systems Command (NAVAIR) at Naval Air Station Patuxent River in July 2002, for the flight test phase of the program. Low-rate initial production began in October 2003, with deliveries to run through 2018. In February 2008, the United States Navy adjusted the contract, with the last 40 AH-1Zs to be built as new airframes instead of the previously planned rebuild of AH-1Ws. In September 2008, the Navy requested an additional 46 airframes for the Marine Corps, bringing the total number ordered to 226. In 2010, the Marine Corps plans to order 189 AH-1Zs with 58 of them being new airframes, with deliveries to continue until 2019. On 10 December, the Department of the Navy approved full-rate production.

Design

The AH-1Z incorporates new rotor technology with upgraded military avionics, weapons systems, and electro-optical sensors in an integrated weapons platform. It has improved survivability and can find targets at longer ranges and attack them with precision weapons.

The AH-1Z's new bearingless, hingeless rotor system has 75% fewer parts than that of four-bladed articulated systems. The blades are made of composites, which have an increased ballistic survivability, and there is a semiautomatic folding system for storage aboard amphibious assault ships. Its two redesigned wing stubs are longer, with each adding a wing-tip station for a missile such as the AIM-9 Sidewinder. Each wing has two other stations for 2.75-inch (70 mm) Hydra 70 rocket pods, or AGM-114 Hellfire quad missile launchers. The Longbow radar can also be mounted on a wing tip station.

The Z-model's integrated avionics system (IAS) has been developed by Northrop Grumman. The system includes two mission computers and an automatic flight control system. Each crew station has two 8x6-inch multifunction liquid crystal displays (LCD) and one 4.2x4.2-inch dual function LCD display. The communications suite combines a US Navy RT-1824 integrated radio, UHF/VHF, COMSEC and modem in a single unit. The navigation suite includes an embedded GPS inertial navigation system (EGI), a digital map system and a low-airspeed air data subsystem, which allows weapons delivery when hovering.

The crew are equipped with the Thales "Top Owl" helmet-mounted sight and display system. The Top Owl has a 24-hour day/night capability and a binocular display with a 40° field of view. Its visor projection provides forward looking infrared (FLIR) or video imagery. The AH-1Z has survivability equipment including the Hover Infrared Suppression System (HIRSS) to cover engine exhausts, countermeasure dispensers, radar warning, incoming/on-way missile warning and on-fuselage laserspot warning systems.

The Lockheed Martin target sight system (TSS) incorporates a third-generation FLIR sensor. The TSS provides target sighting in day, night or adverse weather conditions. The system has various view modes and can track with FLIR or by TV. The same system is also used on the UH-1Y Venom and the KC-130J Harvest HAWK.

MH-6 Little Bird

The MH-6 Little Bird (Killer Egg), and its attack variant AH-6, are light helicopters used for special operations in the United States Army. Originally based on a modified OH-6A, it was later based on the MD 500E, with a single five-bladed main rotor. The newest version, the MH-6M, is based on the MD 530F and has a single, six-bladed main rotor and four-bladed tail rotor.

The A/MH-6 was started in 1960, when the U.S. Army issued Technical Specification 153 for a Light Observation Helicopter (LOH) that could perform personnel transport, escort and attack missions, casualty evacuation, and observation. Twelve companies took part in the competition and Hughes Tool Company's Aircraft Division submitted the Model 369. Two designs, those submitted by Fairchild-Hiller and Bell, were selected as finalists by the Army-Navy design competition board, but the Army later included the helicopter from Hughes as well.

The first Model 369 prototype flew on 27 February 1963. Originally designated the YHO-6A under the Army's designation system, the aircraft was redesignated the YOH-6A under the Department of Defense's new joint system in 1962. Five prototypes were built, fitted with a 252 shp (188 kW) Allison T63-A-5A, and delivered to the U.S. Army at Fort Rucker, Alabama to compete against the other 10 prototype aircraft submitted by Bell and Fairchild-Hiller. In the end, Hughes won the competition and the Army awarded a contract for production in May 1965. The initial order was for 714 aircraft, but that was later increased to 1,300 with an option to buy another 114. Seventy helicopters were built in the first month.

This agile, unarmed helicopter is outfitted with outboard "benches" designed to ferry up to three commandos on each side. There is also a gunship variant, the AH-6. Painted black for nighttime operations, this small aircraft can conduct rapid insertions and extractions of special operations forces into areas its larger brother, the MH-60 Black Hawk, cannot.

Variants

AH-6C

Special Forces attack version. Modified OH-6A to carry weapons and operate as a light attack aircraft for the 160th SOAR(A).

EH-6E

Special Forces electronic warfare, command-post version.

MH-6E

Improved attack helicopter used by US Army special forces units, and stealthy light attack and transport helicopter for US Army special forces units.

AH-6F

Special Forces attack version.

AH-6G

Special Forces attack version.

MH-6H

Special Forces version.

AH/MH-6J

Improved special forces transport and attack versions. Updated light attack helicopter based on the MD 530MG and equipped with an improved engine, FLIR, and a GPS/inertial navigation system.

AH/MH-6M

Also occasionally referred to as the Mission Enhanced Little Bird (MELB), it is a highly modified version of the MD 530 series commercial helicopter.

A/MH-6X

An AH/MH-6M MELB helicopter modified for use as a UAV. It builds upon experience gained through development of the Unmanned Little Bird (ULB) Demonstrator, which is a civil MD 530F modified for autonomous UAV flight. Boeing has announced that this version is marketed solely to other nations, not the U.S., for use as a low-cost attack helicopter.

Boeing AH-64 Apache

The Boeing AH-64 Apache is a four-blade, twin-engine attack helicopter with a tailwheel-type landing gear arrangement, and a tandem cockpit for a two-man crew. The Apache was developed as Model 77 by Hughes Helicopters for the United States Army's Advanced Attack Helicopter program to replace the AH-1 Cobra, and was first flown on 30 September 1975. The AH-64 was introduced to US Army service in April 1986. The AH-64 Apache features a nose-mounted sensor suite for target acquisition and night vision systems. It is armed with a 30-millimeter (1.2 in) M230 Chain Gun carried between the main landing gear, under the aircraft's forward fuselage. It has four hardpoints mounted on stub-wing pylons, typically carrying a mixture of AGM-114 Hellfire missiles and Hydra 70 rocket pods. The AH-64 has a large amount of systems redundancy to improve combat survivability. The U.S. Army selected the AH-64, by Hughes Helicopters, over the Bell YAH-63 in 1976, and later approved full production in 1982. McDonnell Douglas continued production and development after purchasing Hughes Helicopters from Summa Corporation in 1984. The first production AH-64D Apache Longbow, an upgraded version of the original Apache, was delivered to the Army in March 1997. Production has been continued by Boeing Defense, Space & Security; over one thousand AH-64s have been produced to date. The U.S. Army is the primary operator of the AH-64, it has also become the primary attack helicopter of multiple nations, including Greece, Japan, Israel, the Netherlands and Singapore; as well as being produced under license in the United Kingdom as the AgustaWestland Apache. U.S. AH-64s have served in conflicts in Panama, the Persian Gulf, Kosovo, Afghanistan, and Iraq. Israel has made active use of the Apache in its military conflicts in Lebanon and the Gaza Strip, while two coalition allies have deployed their AH-64s in Afghanistan and Iraq.

The AH-64 Apache has a four-blade main rotor and a four-blade tail rotor. The crew sits in tandem, with the pilot sitting behind and above the copilot/gunner. The crew compartment has shielding between the cockpits, such that one crew member can survive hits. The compartment and the rotor blades are designed to sustain a hit from 23-millimeter (0.91 in) rounds. The airframe includes some 2,500 pounds (1,100 kg) of protection against ballistic strikes. The Apache also utilizes a self-sealing fuel system to protect against the loss of fuel caused by ballistic projectiles. The AH-64 is powered by two General Electric T700 turboshaft engines with high-mounted exhausts on either side of the fuselage. Various models of engines have been used on the Apache, those in British service use engines from Rolls-Royce instead of General Electric. In 2004, General Electric Aviation began producing more powerful T700-GE-701D engines, rated at 2,000 shp (1,500 kW) for AH-64Ds. One of the revolutionary features at the introduction of the Apache was its helmet mounted display, the Integrated Helmet and Display Sighting System (IHADSS), among other abilities the pilot or gunner can slave the helicopter's 30 mm automatic M230 Chain Gun to his helmet, making the gun track head movements to point at where he looks. The M230E1 can be alternatively fixed to a locked forward firing position, or controlled via the Target Acquisition and Designation System (TADS).

The AH-64 is designed to endure front-line environments and to operate during the day or night and in adverse weather using avionics, such as the Target Acquisition and Designation System, Pilot Night Vision System (TADS/PNVS), passive infrared countermeasures, GPS, and the IHADSS. A newer system that is replacing TADS/PNVS is Arrowhead (MTADS); it is manufactured by Lockheed Martin, a contract was made on 17 February 2005 to begin equipping all models of American Apaches. The AH-64 is adaptable to numerous different roles within its context as Close Combat Attack (CCA), and has a customizable weapons loadout for the role desired.[38] In addition to the 30-mm M230E1 Chain Gun, the Apache carries a range of external stores on its stub-wing pylons, typically a mixture of AGM-114 Hellfire anti-tank missiles, and Hydra 70 general-purpose unguided 70 mm (2.76 in) rockets. The Stinger and AIM-9 Sidewinder air-to-air missiles and the AGM-122 Sidearm anti-radiation missile were evaluated beginning in the late 1980s. The Stinger was initially selected over the AIM-9, but the US Army is considering the Starstreak air-to-air missile instead. The stub-wing pylons also have mounting points for use during ground helicopter maintenance; though in case of emergency the mount points can be used for harnessing personnel to the wings during transport. External fuel tanks can also be carried by the pylons to increase range and mission time. For rapid deployment and transport around the world, six AH-64 Apaches can be safely fitted inside the cargo hold of a USAF Lockheed C-5 Galaxy.

Sikorsky RAH 66 Comanche

The Sikorsky RAH-66 Comanche (Boeing) was an advanced five-blade armed reconnaissance and attack helicopter designed for the United States Army. The RAH-66 program was canceled in 2004, before mass production began, after nearly $7 billion was spent on the program. During the early 1980s, the U.S. Army began formulating a requirement for a replacement of its helicopters then in service, resulting in the Light Helicopter Experimental program. In 1991, the Boeing-Sikorsky team was chosen to produce prototypes. The Comanche would incorporate stealth technologies, featuring a number of designs previously untried. It was to employ advanced sensors in its reconnaissance role, and was intended to designate targets for the AH-64 Apache. The aircraft was also armed with missiles and rockets to destroy armored vehicles. Two RAH-66 prototypes were built and conducted flight testing from 1996 to 2004, since the cancellation the prototypes have been placed on display. The RAH-66 was intended to be a stealth helicopter; it incorporated multiple techniques in order to reduce its radar cross-section (RCS) and other areas of viability. Radar-absorbent material (RAM) was used on the Comanche, as well as having infrared-suppressant paint applied on its faceted surface; with these measures, the Comanche's RCS was 360 times smaller than the AH-64 Apache attack helicopter. The Comanche's noise signature was noticeably quieter than comparative helicopters; this was partly achieved through the all-composite 5-blade main rotor and tail rotor assembly. The Comanche was equipped with sophisticated navigation and detection systems intended to allow operations at night and in bad weather. Each of the two crew-members had two LCD multi-functional displays in addition to the Helmet-Integrated Display and Sight System (HIDSS). It has a digital fly-by-wire flight control system. Its primary mission was to use its advanced sensors to find and designate targets for attack helicopters, such as the AH-64. The RAH-66 also had its own light armament – it could carry six AGM-114 Hellfire and twelve FIM-92 Stinger missiles split evenly between the two retractable weapons pylons. The Comanche was also to be fitted with the three-barrel XM301 20 mm cannon under its nose. More armament could be accommodated externally but would reduce the effectiveness of the stealth technologies.

The RAH-66 was powered by two LHTEC T800 turboshaft engines. Its fuselage was 43 feet (13 m) long and made of composite material. The F-22 Raptor-derived airframe was designed to fit more easily onto transport ships, enabling it to be deployed to hot spots quickly. If transport assets were not available, the Comanche's ferry range of 1,200 nmi (2,200 km) would allow it to fly to battlefields overseas on its own. The Comanche was specifically tailored to the role of armed scout, replacing the U.S. Army's current armed scout helicopter, the OH-58D Kiowa Warrior, which is an upgraded version of a Vietnam War-era observation helicopter. The Comanche was smaller and lighter than the AH-64.

Eurocopter Tiger

The Eurocopter Tiger (company designation EC 665) is an attack helicopter manufactured by Eurocopter. In Germany it is known as the Tiger; in France and Spain it is called the Tigre.

In 1984, the French and West German governments issued a requirement for an advanced multi-role battlefield helicopter. A joint venture consisting of Aérospatiale and MBB was subsequently chosen as the preferred supplier. Due to high costs, the program was cancelled in 1986, but was relaunched during 1987. Subsequently, in November 1989, Eurocopter received a contract to build five prototypes. Three were to be unarmed testbeds and the other two armed prototypes: one for the French escort helicopter variant and the other for the German anti-tank variant.

The first prototype first flew in April 1991. When Aérospatiale and MBB, among others, merged in 1992 to form the Eurocopter Group, the Tiger program was transferred as well. Serial production of the Tiger began in March 2002 and the first flight of the first production Tiger HAP for the French Army took place in March 2003. The delivery of the first of the eighty helicopters ordered by the French took place in September 2003. At the end of 2003, deliveries began of the 80 UHT version combat support helicopters ordered by Germany to the Federal Office of Defense Technology and Procurement. Due to technical problems, operational capability is not expected to be achieved before the end of 2012 at the latest.

Variants

Tiger HAP

The Tiger HAP/HCP (Hélicoptère d'Appui Protection, French for "Support and Escort Helicopter" / Hélicoptère de Combat Polyvalent French for "Multipurpose Combat Helicopter") is a medium-weight air-to-air combat and fire support helicopter built for the French Army. It is fitted with a chin-mounted 30 mm gun turret and can carry 68 mm SNEB unguided rockets or 20 mm machine cannons for the fire support role as well as Mistral air-to-air missiles.

UH Tiger

The UHT (from Unterstützungshubschrauber Tiger German for Support Helicopter Tiger) is a medium-weight multi-role fire support helicopter built for the Bundeswehr (German Armed Forces). The UHT can carry PARS 3 LR "fire and forget" and/or HOT3 anti-tank missiles as well as 70 mm Hydra air-to-ground fire support rockets. Four AIM-92 Stinger missiles (2 on each side) are mounted for air-to-air combat. Unlike the HAP/HCP version it has no integrated gun turret, but a 12.7 mm gunpod can be fitted if needed. The German Army decided against the French 30 mm GIAT cannon that is used on other Tiger versions because it was dissatisfied with the heavy recoil of this weapon. The upgrade of the UHT with the Rheinmetall RMK30, a 30 mm recoilless autocannon, is not yet clarified due to the budget. Another noticeable difference with the HAP version is the use of a mast-mounted sight, which has second-generation infrared and CCD TV cameras. Countermeasures include radar/laser/missile launch/missile approach warning receivers and decoy launchers.

In August 2009, the German magazine Der Spiegel reported that the ten operational Tiger aircraft in the German Army were only suitable for pilot training, while others have not been accepted due to defects. The German defense ministry said that the helicopter has "serious defects particularly with its wiring," while Eurocopter said "Corrective measures related to wiring problems have been developed, agreed by the customer and are being implemented," and that two corrected helicopters will be handed over to the German military in two months.

Tiger ARH

The Tiger ARH (Armed Reconnaissance Helicopter) is the version ordered by the Australian Army to replace its OH-58 Kiowas and UH-1 Iroquois-based 'Bushranger' gunships. The Tiger ARH is a modified and upgraded version of the Tiger HAP with upgraded MTR390 engines as well as a laser designator incorporated in the Strix sight for the firing of Hellfire II air-to-ground missiles. Instead of SNEB unguided rockets, the ARH will use 70 mm (2.75 in) rockets from Belgian developer, Forges de Zeebruges (FZ). 22 of the variant were ordered in December 2001. Most of the helicopters will be operated by the 1st Aviation Regiment based at Robertson Barracks in Darwin. The first two ARH helicopters were delivered to Australia on 15 December 2004. ARH deliveries were to be completed by June 2010. Full operating capability was planned for December 2011.

Tiger HAD

The Tiger HAD (Hélicoptère d'Appui Destruction, in French or Helicoptero de Apoyo y Destrucción in Spanish for "Support and Attack Helicopter") version is essentially identical to the HAP version, but with 14% more engine power available due to the upgraded Enhanced MTR390 engines (1464 shp) and a better ballistic protection, as a result of the specific requests made by the Spanish Army. It can also be equipped with the PARS 3 LR anti-tank missiles that were originally developed for the German UHT version, the Hellfire II and is equipped with Spike ER for Spanish Army. The helicopter is suited for a support and fire suppression role and has been selected by the Spanish Army. The French Army Light Aviation (ALAT) decided to upgrade most of their HAP helicopters to the HAD-Variant and thus the former HAC Variant (i.e. Hélicoptère Anti-Char or "Anti-Tank Helicopter") was cancelled.

Sikorsky HH-60 Pave Hawk, Search and Rescue Helicopter

Sikorsky HH-60G Pave Hawk is a twin turboshaft engine helicopter in service with the United States Air Force. It is a derivative of the UH-60 Black Hawk and incorporates the US Air Force PAVE electronic systems program. The HH/MH-60 is a member of the Sikorsky S-70 family. The MH-60G Pave Hawk's primary mission is insertion and recovery of special operations personnel, while the HH-60G Pave Hawk's core mission is recovery of personnel under stressful conditions, including search and rescue. Both versions conduct day or night operations into hostile environments. Because of its versatility, the HH-60G may also perform peace-time operations. Such tasks include civil search and rescue, emergency aeromedical evacuation (MEDEVAC), disaster relief, international aid, counter-drug activities and NASA space shuttle support.

In 1981, the U.S. Air Force chose the UH-60A Black Hawk to replace its HH-3E Jolly Green Giant helicopters. After acquiring some UH-60s, the Air Force began upgrading each with an air refueling probe and additional fuel tanks in the cabin. The machine guns were changed from .308 in (7.62 mm) M60s to 0.50 in (12.7 mm) XM218s. These helicopters were referred to as "Credible Hawks" and entered service in 1987. Afterward, the Credible Hawks and new UH-60As were upgraded and designated MH-60G Pave Hawk. These upgrades were to be done in a two step process. But funding only allowed 16 Credible Hawks to receive the second step equipment. These helicopters were allocated to special operations use. The remaining 82 Credible Hawks received the first step upgrade equipment and were used for combat search and rescue. In 1991, these search and rescue Pave Hawks were redesignated HH-60G. The Pave Hawk is a highly-modified version of the Sikorsky UH-60 Black Hawk. It features an upgraded communications and navigation suite that includes an integrated inertial navigation/global positioning/Doppler navigation systems, satellite communications, secure voice, and Have Quick communications.

All HH-60Gs have an automatic flight control system, night vision goggles lighting and forward looking infrared system that greatly enhances night low-level operations. Additionally, some Pave Hawks have color weather radar and an engine/rotor blade anti-ice system that gives the HH-60G an all-weather capability. Pave Hawk mission equipment includes a retractable in-flight refueling probe, internal auxiliary fuel tanks, two crew-served (or pilot-controlled) 7.62 mm miniguns or .50-caliber machine guns and an 8,000 pound (3,600 kg) capacity cargo hook. To improve air transportability and shipboard operations, all HH-60Gs have folding rotor blades. Pave Hawk combat enhancements include a radar warning receiver, infrared jammer and a flare/chaff countermeasure dispensing system. HH-60G rescue equipment includes a hoist capable of lifting a 600 pound (270 kg) load from a hover height of 200 feet (60 m), and a personnel locating system. A limited number of Pave Hawks are equipped with an over-the-horizon tactical data receiver that is capable of receiving near real-time mission update information.

The U.S. Air Force HH-60G Pave Hawk is operated by the Air Combat Command (ACC), U.S. Air Forces in Europe (USAFE), Pacific Air Forces (PACAF), Air Education and Training Command (AETC), the Air Force Reserve Command (AFRC) and the Air National Guard (ANG) as of 2011. During Operation Desert Storm, Pave Hawks provided combat search and rescue coverage for coalition Air Forces in western Iraq, Saudi Arabia, coastal Kuwait and the Persian Gulf. They also provided emergency evacuation coverage for U.S. Navy sea, air and land (SEAL) teams penetrating the Kuwaiti coast before the invasion.

All MH-60Gs subsequently divested by AFSOC; most MH-60Gs were redesignated as HH-60Gs in 1991 and transferred to Air Combat Command (ACC) and ACC-gained Air Force Reserve Command (AFRC) and Air National Guard (ANG) units. During Operation Allied Force, the Pave Hawk provided continuous combat search and rescue coverage for NATO air forces, and successfully recovered two U.S. Air Force pilots who were isolated behind enemy lines. In March 2000, three Pave Hawks deployed to Hoedspruit Air Force Base in South Africa, to support international flood relief operations in Mozambique. The HH-60Gs flew 240 missions in 17 days and delivered more than 160 tons of humanitarian relief supplies. Air Force Pave Hawks from the Pacific theater also took part in a massive humanitarian relief effort in early 2005 in Sri Lanka to help victims of the tsunami. In the fall of 2005, Pave Hawks from various Air Force commands participated in rescue operations of Hurricane Katrina survivors, rescuing thousands of stranded people. Pave Hawks have regularly operated in Operation Enduring Freedom and Operation Iraqi Freedom supporting Army and Marine Corps ground combat operations and standby search and rescue support for U.S. and Coalition fixed-wing combat aircraft supporting those ground operations. In March 2010, the U.S. Air Force announced a recapitalization plan to return its 99-aircraft inventory to 112 airframes by incremental replacement aging HH-60Gs. A secondary plan for loss replacement of thirteen attrited HH-60s, seven of which have been lost in combat since 2001, has begun implementation. The Air Force is deferring secondary combat search and rescue requirements that called for a larger helicopter. A UH-60M-based version was being offered as a replacement.

Mil Mi 24

During the early 1960s, it became apparent to Soviet designer Mikhail Leont'yevich Mil that the trend towards ever-increasing battlefield mobility would result in the creation of flying infantry fighting vehicles, which could be used to perform both fire support and infantry transport missions. The first expression of this concept was a mock-up unveiled in 1966 in the experimental shop of the Ministry of Aircraft's factory number 329 where Mil was head designer. The mock-up designated V-24 was based on another project, the V-22 utility helicopter, which itself never flew. The V-24 had a central infantry compartment that could hold eight troops sitting back to back, and a set of small wings positioned to the top rear of the passenger cabin, capable of holding up to six missiles or rockets and a twin-barreled GSh-23L cannon fixed to the landing skid.

Mil proposed the design to the heads of the Soviet armed forces, and while he had the support of a number of strategists, he was opposed by several more senior members of the armed forces who believed that conventional weapons were a better use of resources. Despite the opposition, Mil managed to persuade the defence minister's first deputy, Marshal Andrey A. Grechko, to convene an expert panel to look into the matter. While the panel's opinions were mixed, supporters of the project eventually held sway and a request for design proposals for a battlefield support helicopter was issued. The development of gunships and attack helicopters by the US Army during the Vietnam War convinced the Soviets of the advantages of armed helicopter ground support doctrine, which had a positive influence on moving forward with the development of the Mi-24.

Mil engineers prepared two basic designs: a 7-ton single-engine design and a 10.5-ton twin-engine design, both based on the 1,700 hp Izotov TV3-177A turboshaft. Later, three complete mock-ups were produced, along with five cockpit mock-ups to allow the pilot and weapon station operator positions to be fine-tuned.

The Kamov design bureau suggested an army version of their Ka-25 Hormone ASW helicopter as a low-cost option. This was considered but later dropped in favor of the new Mil twin-engine design. A number of changes were made at the insistence of the military, including the replacement of the 23 mm cannon with a rapid-fire heavy machine gun mounted in a chin turret, and the use of the 9K114 Shturm (AT-6 Spiral) anti-tank missile.

A directive was issued on 6 May 1968 to proceed with development of the twin-engine design. Work proceeded under Mil until his death in 1970. Detailed design work began in August 1968 under the codename Yellow 24. A full scale mock-up of the design was reviewed and approved in February 1969. Flight tests with a prototype began on 15 September 1969 with a tethered hover, and four days later the first free flight was conducted. A second prototype was built, followed by a test batch of ten helicopters.

Acceptance testing for the design began in June 1970, continuing for 18 months. Changes made in the design addressed structural strength, fatigue problems and reduced vibration levels. Also, a 12-degree anhedral was introduced to the wings to address the aircraft's tendency to Dutch roll at speeds in excess of 200 km/h, and the Falanga missile pylons were moved from the fuselage to the wingtips. The tail rotor was moved from the right to the left side of the tail, and the rotation direction reversed. The tail rotor now rotated up on the side towards the front of the aircraft, into the downwash of the rotor, which increased the efficiency of the tail rotor. A number of other design changes were made until the production version Mi-24A (izdeliye 245) entered production in 1970, obtaining its initial operating capability in 1971 and was officially accepted into the state arsenal in 1972.

In 1972, following completion of the Mi-24, development began on a unique attack helicopter with transport capability. The new design had a reduced transport capability (3 troops instead of 8) and was called the Mi-28, and that of the Ka-50 attack helicopter, which is smaller and more maneuverable and does not have the large cabin for carrying troops. In October 2007, the Russian Air Force announced it would replace its Mi-24 fleet with Mi-28s and Ka-50s by 2015. However due to economics the Russian Army will upgrade some Mi-24s and keep them in service past 2015. The Russian navy will keep its Hinds in service for years to come as well.

Design

The core of the aircraft was derived from the Mil Mi-8 (NATO reporting name "Hip"): two top-mounted turboshaft engines driving a mid-mounted 17.3 m five-blade main rotor and a three-blade tail rotor. The engine configuration gave the aircraft its distinctive double air intake. Original versions have an angular greenhouse-style cockpit; Model D and later have a characteristic tandem cockpit with a "double bubble" canopy. Other airframe components came from the Mi-14 "Haze". Two mid-mounted stub wings provide weapon hardpoints, each offering three stations, in addition to providing lift. The load-out mix is mission dependent; Mi-24s can be tasked with close air support, anti-tank operations, or aerial combat.

The body is heavily armored and can resist impacts from .50 caliber (12.7 mm) rounds from all angles, including the titanium rotor blades. The cockpit is protected by ballistic-resistant windscreens and a titanium-armored tub. The cockpit and crew compartment are overpressurized to protect the crew in NBC conditions.

Considerable attention was given to making the Mi-24 fast. The airframe was streamlined, and fitted with retractable tricycle undercarriage landing gear to reduce drag. The wings provide considerable lift at high speed, up to a quarter of total lift. The main rotor was tilted 2.5° to the right from the fuselage to counteract dissymmetry of lift at high speed and provide a more stable firing platform. The landing gear was also tilted to the left so the rotor would still be level when the aircraft was on the ground, making the rest of the airframe tilt to the left. The tail was also asymmetrical to give a side force at speed, thus unloading the tail rotor.

A modified Mi-24B, named A-10, was used in several speed and time to climb world record attempts. The helicopter had been modified to reduce weight as much as possible, and among the measures used was to remove the stub wings. The speed record over a closed 1000 km course set on 13 August 1975 of 332.65 km/h still stands, as does many of the female specific records set by the all female crew of Galina Rastorgoueva and Ludmila Polyanskaia. On 21 September 1978 the A-10 set the absolute speed record for helicopters with 368.4 km/h over a 15/25 km course. The record stood until 1986 when it was broken by the current record holder, a modified Westland Lynx

Comparison to western helicopters

As a combination gunship and troop transport, the Mi-24 has no direct NATO counterpart. While the UH-1 ("Huey") helicopters were used in the Vietnam War either to ferry troops, or as gunships, they were not able to do both at the same time. Converting a UH-1 into a gunship meant stripping the entire passenger area to accommodate extra fuel and ammunition, and removing its troop transport capability. The Mi-24 was designed to do both, and this was greatly exploited by airborne units of the Soviet Army during the 1980–89 Soviet war in Afghanistan. The closest Western equivalent was the Sikorsky S-67 Blackhawk, which used many of the same design principles and was also built as a high-speed, high-agility attack helicopter with limited troop transport capability. It was also designed using many components from the existing Sikorsky S-61. The S-67, however, was never adopted for service. Another relatively close western equivalent is the MH-60 Direct Action Penetrator, a special purpose variant of the Sikorsky UH-60 Black Hawk, which is capable of mounting a variety of weapons on its stub wings, including AGM-114 Hellfire missiles and Hydra 70 rockets.

Eurocopter Tiger

The Eurocopter Tiger (company designation EC 665) is an attack helicopter manufactured by Eurocopter. In Germany it is known as the Tiger; in France and Spain it is called the Tigre.

Variants

Tiger HAP

UH Tiger

Tiger ARH

Tiger HAD