Apache Helicopter
ABSTRACTThe Apache Helicopter is a revolutionary development in the history of war. It is essentially a flying tank- a helicopter designed to survive heavy attack and inflict massive damage. It can zero in on specific targets, day or night, even in terrible weather. As you might expect, it is a terrifying machine to ground forces.
Boeing AH-64 Apache
A radar-less AH-64D Longbow Apache from U.S. Army's 101st Aviation Regiment in Iraq
Role:Attack helicopter
National origin:United States
Manufacturer Hughes Helicopters
McDonnell Douglas
Boeing Defense, Space & Security
First flight 30 September 1975[1]
Introduced April 1986[2]
Status Active service
Primary user United States Army
Israel Air Force
Egyptian Air Force
Hellenic Army
Produced 1983–present
Number built
1,174 as of February 2010[3]
Unit cost
AH-64A: US$20 million (2007),
AH-64D (AH-64A upgrade): US$18 million (2007)[4]
Variants
AgustaWestland Apache
The Boeing AH-64 Apache is a four-blade, twin-engine attack helicopter with tailwheel-type landing gear arrangement, and tandem cockpit for a crew of two. 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. First flown on 30 September 1975, the AH-64 features a nose-mounted sensor suite for target acquisition and night vision systems. The Apache 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 and Hydra 70 rocket pods. The AH-64 also features double- and triple-redundant aircraft systems to improve survivability for the aircraft and crew in combat, as well as improved crash survivability for the pilots.
The U.S. Army selected the AH-64 over the Bell YAH-63 in 1976, awarding Hughes Helicopters a pre-production contract for two more aircraft. In 1982, the Army approved full production. McDonnell Douglas continued production and development after purchasing Hughes Helicopters from Summa Corporation in 1984. The first production AH-64D Apache Longbow, a greatly upgraded version of the original Apache, was delivered to the Army in March 1997. AH-64 production is continued by the Boeing Defense, Space & Security division; over one thousand AH-64s have been produced to date.
The U.S. Army is the primary operator of the AH-64, however it has also become the primary attack helicopter of several nations it has been exported to, including the United Kingdom, Israel, Japan, Greece and the Netherlands. U.S. AH-64s have served in conflicts in Panama, Persian Gulf War, Kosovo War, Afghanistan, and Iraq. Israel has made active use of the Apache in its military conflicts in Lebanon and Gaza Strip; while two coalition allies have deployed their AH-64s in Afghanistan and Iraq.
Development
Advanced Attack Helicopter
Following the cancellation of the AH-56 Cheyenne in 1972, in favor of United States Air Force and Marine Corps projects like the A-10 Thunderbolt II and Harrier Jump Jet, the United States Army sought an aircraft to fill an anti-armor attack role that would still be under Army command;[5][6] the 1948 Key West Agreement forbade the Army from owning fixed-wing aircraft. The Army wanted an aircraft better than the AH-1 Cobra in firepower, performance and range. It would have the maneuverability for terrain following nap-of-the-earth (NoE) flying.[7] To this end, the US Army issued a Request For Proposals (RFP) for an Advanced Attack Helicopter (AAH) on 15 November 1972.[8][9] As a sign of the importance of this project, in September 1973 the Army designated their five most important projects, the "Big Five" with AAH included.
Proposals were submitted by five manufacturers: Bell, Boeing Vertol (teamed with Grumman), Hughes, Lockheed, and Sikorsky. In July 1973, the U.S. Department of Defense selected finalists Bell and Hughes Aircraft's Toolco Aircraft Division (later Hughes Helicopters). This began the phase 1 of the competition.[11] Each company built prototype helicopters and went through a flight test program. Hughes' Model 77/YAH-64A prototype first flew on 30 September 1975, while Bell's Model 409/YAH-63A prototype first flew on 1 October. After evaluating test results, the Army selected Hughes' YAH-64A over Bell's YAH-63A in 1976. Reasons for selecting the YAH-64A included its more damage tolerant four-blade main rotor and the instability of the YAH-63's tricycle landing gear arrangement.
The AH-64A then entered phase 2 of the AAH program. This called for building three pre-production AH-64s, and upgrading the two YAH-64A flight prototypes and the ground test unit up to the same standard.[12] Weapons and sensor systems were integrated and tested during this time, including the new Hellfire missile.[14]
Into production
In 1981, three pre-production AH-64As were handed over to the US Army for Operational Test II. The Army testing was successful, but afterward it was decided to upgrade to the more powerful T700-GE-701 version of engine, rated at 1,690 shp (1,259 kW). The AH-64 was named the Apache in late 1981, keeping with the Army's traditional use of American Indian tribal names for its helicopters and it was approved for full scale production in 1982.[15] In 1983, the first production helicopter was rolled out at Hughes Helicopter's facility at Mesa, Arizona. Hughes Helicopters was purchased by McDonnell Douglas for $470 million in 1984.[16] The helicopter unit later became part of The Boeing Company with the merger of Boeing and McDonnell Douglas in August 1997.[17] In 1986, the incremental or flyaway cost for the AH-64A was US$7.03 million and the average unit cost was approximately US$13.9 million based on total costs.[16]
In the mid-1980s, McDonnell Douglas studied an improved "AH-64B" design with an updated cockpit, new fire control system and other upgrades. In 1988 funding was approved for a multi-stage upgrade program to improve sensor and weapon avionic systems and incorporate some digital systems.[18] However, improved technology was becoming available. It was decided to cancel the upgrade program for more ambitious changes. This would lead to the more advanced AH-64D Apache Longbow. Development of the AH-64D was approved by the Defense Acquisition Board in August 1990. The first AH-64D Apache Longbow prototype was flown on 15 April 1992,[19] and testing of the prototypes ended in April 1995 after they had significantly outperformed the AH-64A model.[20][21] On 13 October 1995 full-scale production of the Apache Longbow was approved[22] and a $1.9 billion five year contract was signed in August 1996 to upgrade and rebuild 232 existing AH-64 Apaches The first production AH-64D flew on 17 March 1997 and was delivered on 31 March 1997. The cost of the AH-64D program totaled US$11 billion through 2007
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