The Apache is a twin-engined army attack helicopter developed by McDonnell Douglas (now Boeing). It entered service with the US Army in 1984 and has been exported to Egypt, Greece, Israel, the Netherlands, Japan, Saudi Arabia, United Arab Emirates (UAE) and the UK.
The AH-64D Longbow is fitted with the Longbow millimetre wave fire control radar and the Longbow Hellfire missile. 501 AH-64A Apaches upgraded to AH-64D standard have been delivered to the US Army. Deliveries completed in August 2006.
International Apache orders and deliveries
The Longbow has been ordered by the Netherlands (30, deliveries complete), Singapore (20 deliveries complete, first delivered in May 2002), Israel (designated "Seraph" nine new, nine remanufactured, first delivered April 2005) and Egypt (35, remanufactured, deliveries completed in January 2007).
The Royal Netherlands Air Force received its first AH-64D Apache and first AH-64D Apache Block III aircraft in May 1998 and in May 2012 respectively.
AH-64A/D Apache upgrades
The first of the upgraded block II Apaches was delivered to the US Army in February 2003. Block II included upgrades to the digital communications systems of 96 A-model Apaches to improve communications within the "tactical internet". In October 2007, Boeing delivered the first extended block II to the US Army.
Block III includes increasing digitisation, the joint tactical radio system, enhanced engines and drive systems, capability to control UAVs and new composite rotor blade. The new blades, which successfully completed flight testing in May 2004, increase the Apache's cruise speed, climb rate and payload capability.
Apache weapons
A 30mm automatic Boeing M230 chain gun is located under the fuselage. It provides a rate of fire of 625 rounds a minute. The helicopter has capacity for up to 1,200 rounds of ammunition.
The AH-64D is armed with the Lockheed Martin / Boeing AGM-114D Longbow Hellfire air-to-surface missile which has a millimetre wave seeker which allows the missile to perform in full fire and forget mode. Range is 8km to 12km.
"The helicopter has capacity for up to 1,200 rounds of ammunition."
The Apache can be equipped with air-to-air missiles (Stinger, AIM-9 Sidewinder, Mistral and Sidearm) and the advanced precision kill weapon system (APKWS), formerly known as Hydra, family of guided and unguided 70mm rockets. Plans to arm the Apache with the advanced precision kill weapon system (APKWS) II, a laser-guided version of the Hydra were shelved in the FY2008 budget. The US Army awarded BAE Systems a development contract for the APKWS II in April 2006.
British Army AH mk1 helicopters are armed with the CRV7 70mm rocket system from Bristol Aerospace of Winnipeg, Manitoba.
The Longbow Apache carries the combination of armaments chosen for the particular mission. In the close support role, the helicopter carries 16 Hellfire missiles on four four-rail launchers and four air-to-air missiles.
Sensors
The AH-64D Longbow Apache is equipped with the Northrop Grumman millimetre-wave Longbow radar. The Longbow fire control radar incorporates an integrated radar frequency interferometer for passive location and identification of radar-emitting threats. An advantage of millimetre wave is that it performs under poor-visibility conditions and is less sensitive to ground clutter. The short wavelength allows a very narrow beamwidth, which is resistant to countermeasures.
The Longbow Apache can effect an attack in 30 seconds. The radar dome is unmasked for a single radar scan and then remasked. The processors determine the location, speed and direction of travel of a maximum of 256 targets.
The target acquisition designation sight, TADS (AN/ASQ-170), and the pilot night vision sensor, PNVS (AN/AAQ-11), were developed by Lockheed Martin. The turret-mounted TADS provides direct-view optics, television and three-fields-of-view forward-looking infrared (FLIR) to carry out search, detection and recognition, and Litton laser rangefinder / designator. PNVS consists of a FLIR in a rotating turret located on the nose above the TADS. The image from the PNVS is displayed in the monocular eyepiece of the Honeywell integrated helmet And display sighting system, IHADSS, worn by the pilot and copilot / gunner.
Lockheed Martin has developed a new targeting and night vision system for the Apache, using second-generation long-wave infrared sensors with improved range and resolution. The new system is called Arrowhead and has a targeting FLIR with three fields of view, a dual field-of-view pilotage FLIR, a CCD TV camera, electronic zoom, target tracker and auto-boresight.
"Lockheed Martin has developed a new targeting and night vision system for the Apache."
Arrowhead entered production in December 2003 and the first unit was delivered to the US Army in May 2005. The first Arrohead system was integrated to the Apache helicopter in June 2005. A total of 704 US Army Apaches were to be equipped with Arrowhead by 2011. The 500th delivery was made in 2008 and the remaining deliveries were completed as scheduled. The US Army has also placed follow-on contracts for additional Arrowhead fittings to its fleet of Apaches, increasing the total number of Arrowhead integrations for the US Army.
A contract to equip the UK AH Mk1 helicopters with Arrowhead was placed in May 2005. The first two were delivered in November 2008 and deliveries concluded in 2010.
Countermeasures
The Apache is equipped with an electronic warfare suite consisting of: AN/APR-39A(V) radar warning receiver from Northrop Grumman (formerly Litton) and Lockheed Martin; Lockheed Martin AN/APR-48A Radar Frequency Interferometer Electronic Support target acquisition system; AN/ALQ-144 infra-red countermeasures set from BAE Systems IEWS (formerly Sanders, a Lockheed Martin company); AN/AVR-2 laser warning receiver from Goodrich (formerly Hughes Danbury Optical Systems then Raytheon); AN/ALQ-136(V) radar jammer developed by ITT; and chaff dispensers.
US Army Longbow Apaches were to be fitted with the ITT AN/ALQ-211 SIRCM (suite of integrated radio frequency countermeasures) suite, however the availability of funding for this project is uncertain.
UK AH mk1 Apaches are fitted with BAE Systems helicopter integrated defensive aids suite (HIDAS), also chosen by Kuwait and Greece. HIDAS, which includes the Sky Guardian 2000 radar warning receiver, entered service on the AH mk1 in July 2003.
Israeli AH-64D helicopters are fitted with the Elisra Seraph self-protection system, including SPS-65 missile warner and SPJ-40 radar jammer.
Dutch AH-64D helicopters are being fitted with the Northrop Grumman directional infrared countermeasures (DIRCM) pod.
Engines
The Apache is equipped with two turboshaft engines, each providing 1,265kW. The American AH-64D has General Electric T700-GE-701 engines and the UK Apache is fitted with RTM322 engines from Rolls-Royce / Turbomeca.
Performance
The AH-64 Apache can climb at a rate of 889m/min. The maximum and cruise speeds of the helicopter are 279km/h and 260km/h respectively. The ferry range and service ceiling of the helicopter are 1,900km and 6,400m respectively. The endurance is 3 hours 9 minutes. The helicopter weighs around 5,165kg, while the maximum take-off weight is 10,433kg.