AH-64B: Cancelled in 1992. Was planned near-term upgrade of 254 AH-64As with improvements derived from operating experience in 1991 Gulf War.
AH-64C: Previous designation for upgrade of AH-64As to near AH-64D. apart from omission of
Longbow radars to 500; these would equip regular Army units. Army National Guard and Army Reserve undergoing service life extension programme. Decision still awaited in April 2000.
Under original programme, AH-64D to equip 26 battalions, although this may be reduced to 16 of regular Army; three companies, each with eight helicopters, per battalion. Longbow can track flying targets and see through rain, fog and smoke that defeat FLIR and TV. RF Hellfire, which delivered to US Army from November 1996, can operate at shorter ranges; it can lock on before launch or launch on co-ordinates and lock on in flight; Longbow scans through 360º for aerial targets or scans over 270º in 90º sectors for ground targets; mast-mounted rotating antenna weighs 113 kg (250 lb). Longbow radar transmitter subject of redesign in late 1997 to overcome poor performance of some electrical components in low temperatures; eliminate lengthy and costly manual integration necessary to achieve required output; and avoid shortages of critical components which suppliers reported in 1995 that they would no longer provide. New transmitter meets or surpasses original specification and is fully interchangeable with original unit.
Further modifications include `manprint' cockpit with large displays, air-to-air missiles, digital autostabiliser, integrated GPS/Doppler/INS/air data/laser/radar altimeter navigation system, digital communications, faster target handoff system, and enhanced fault detection with data transfer and recording. Cockpit displays initially monochrome, but these replaced by colour displays with effect from 27th production conversion; first flight of AH-64D with colour displays on 12 September 1997. AH-64D No.1 made first Hellfire launch on 21 May 1993; first RF Hellfire launch 4 June 1994; first demonstration of digital air-to-ground data communications with Symetrics Industries improved data modem, 8 December 1993.
First preproduction AH-64D conversion completed remanufacture in September 1995; aircraft made successful first flight at Mesa on 29 September 1995.
Multiyear contract, worth US$1.9 billion, covering 232 AH-64Ds (retrospectively including advanced acquisition aircraft) over five year period signed 16 August 1996; further 298 conversions to be acquired in follow-on multiyear contract covering FY01 to FY05. Initial contract also included 227 Longbow radars, 13,311 Hellfire missiles and 3,296 launchers. AH-64D deliveries to US Army began 31 March 1997 and total of 16 handed over by end November 1997. Delivery of 24th and last Lot 1 aircraft accomplished 4 March 1998, with US Army having accepted total of 48 by end of October 1998, when production rate was three per month; 100th remanufactured AH-64D delivered to US Army in early December 1999.
Initial AH-64D battalion (1-227 AvRgt) at Fort Hood, Texas fully equipped by end July 1998 and attained combat-ready status on 19 November 1998, after eight month training programme at company and battalion level which included four live fire exercises and more than 2,500 flight hours. Second unit is 2-101 AvRgt at Fort Campbell, Kentucky, which certified as combat-ready on 28 October 1999; third will be 1-3 AvRgt at Hunter AAF, Fort Stewart, Georgia.
Entire US Army fleet grounded at start of November 1999 to permit replacement of faulty hanger bearing assemblies in tail rotor system; initial inspection completed by mid-November revealed need to replace assemblies on up to 420 helicopters. Priority given to overseas-based units, with entire rectification programme likely to mean that some Apaches could remain grounded for up to 10 months.
Customers
US Army 827 AH-64A (including six prototypes), of which last delivered 30 April 1996; see Programme and Current Versions for details. Confirmed export orders and firm commitments totalled 221 at end of 1999. Israel ordered 18 in March 1990; first two delivered 12 September 1990 to 113 Squadron, powered by T700-GE-701s; further 24 second-hand (including 18 US Army Europe AH-64As delivered in September 1993), for 113 and 127 Squadrons; first two units based at Ramon; deliveries to 190 Squadron at Ramat David, 1995. After rejecting purchase of new-build AH-64D Apache Longbow on cost grounds, Israel submitted formal request to US in fourth quarter of 1999 for upgrade of existing AH-64A to AH-64D; initial batch of 12 to be modified, with further 12 subject to option.
Deliveries began in April 1993 to Saudi Arabia (12) and in 1994 to Egypt (24). Further orders from Greece (20) and United Arab Emirates (20), both in December 1991; six handed over to UAE on 30 October 1993; 14 followed in 1994. Greek deliveries from February 1995 for training in USA; initial six Apaches ferried to New Orleans, Louisiana, for shipment to Greece on 9 June 1995. Ten more ordered for UAE in June 1994; 12 more to Egypt approved early 1995.