Boeing AH-64 Apache - Design

Design

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 at least 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 uses a self-sealing fuel system to protect against the loss of fuel caused by ballistic projectiles. The aircraft was designed to meet the crashworthiness requirements of MIL-STD-1290, which specifies minimum requirement for crash impact energy attenuation to minimize crew injuries and fatalities. This was achieved through incorporation of increased structural strength, crashworthy landing gear, crashworthy crew seats and a crashworthy fuel system.

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's standard of performance for aerial gunnery is to achieve at least one hit out of 30 shots fired at a wheeled vehicle 800–1200 m away.

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 issued in February 2005 to begin equipping all U.S. Apaches.

The AH-64 is adaptable to numerous different roles within its context as Close Combat Attack (CCA), it has a customizable weapons loadout mounted on stub-wings for the role desired. 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 stub-wing pylons have mounting points which make maintenance easier; these mountings can be used to secure personnel to the wings for transport for emergencies.

Starting in the late 1980s, the Stinger and AIM-9 Sidewinder air-to-air missiles and the AGM-122 Sidearm anti-radiation missile were evaluated for use upon the AH-64. The Stinger was initially selected over the AIM-9, but the U.S. Army is considering the Starstreak air-to-air missile instead. External fuel tanks can also be carried to increase range and mission time.

For rapid deployment and transport around the world, up to six AH-64 Apaches can be safely fitted inside the cargo hold of a USAF Lockheed C-5 Galaxy.

In August 2012, some Apaches in Afghanistan were equipped with the Ground Fire Acquisition System (GFAS). 24 AH-64D Block IIs were equipped with the system, which is intended to detect and aim the Apaches' sensors at ground-based weapons fire sources. The GFAS consists of two small sensor pods, which home in on muzzle flashes. Working with the AH-64D's own sensors, the system's infrared camera tell the aircraft exactly where the ground-based threats are and the distance between them. The GFAS is effective in all light conditions and has a 120 degree field of view.