The story of the McDonnell Douglas Helicopter company's AH-64A "Apache" helicopter is filled with superlatives.

Army and company officials call it the most impressive attack helicopter in the world - the fastest, the best equipped - the most deadly to enemy targets. No tank armor exists the Apache's Hellfire missiles can't penetrate, the manufacturer touts.The gunship even does things the military won't allow its pilots to try, like fly upside down.

The Apache cruises, fully loaded, at speeds of up to 170 mph - backs up or flies sideways at about 60 mph - and has a range of up to 1,000 nautical miles. It has an impressive list of maneuvering features and is equipped with hardware as basic as wire cutters designed to clip unseen utility wires, and features sophisticated video sighting and recording devices that can read the license plate on a vehicle four miles away.

It's designed to fly at night and in bad weather - all at altitudes low enough to be below the sight of land-based anti-aircraft batteries. It's quick sighting and computer-coordinated firing system allows the two-member crew to hide behind a ridge, pop up, fire at targets several miles away and duck behind cover again to dodge return fire.

Cosmetically, it's not a particularly attractive aircraft. (But that's not a problem considering frightening faces soldiers painted on aircraft during World War II.) A 30mm chain gun cannon that carries 1,200 rounds, 76 70mm aerial rockets and 16 Hellfire missiles comprise the helicopter's standard armaments. McDonnell Douglas engineers have also tested a number of other top-notch rockets and missiles, like the Sidearm anti-radiation missile and the Sidewinder air-to-air missile.

Armor and other safety features are designed to allow the crew to walk away from many crashes; an armored shield between the pilot and co-pilot would withstand a grenade blast, according to company spokesmen.

While the Apache is now state-of-the art, Phil Mooney, McDonnell Douglas department manager in charge of U.S. military marketing is the first to point out that a second generation of Apaches is already being researched and should be in production by the 1990s.

Until then, the military has ordered 675 Apaches and the state department has already approved foreign sales to several NATO countries. The current U.S. military contract has the company producing 10 Apaches per month for delivery to the Army's active duty, reserve and guard components around the U.S., in Korea and in Europe.

The company expects to deliver 975 Apaches, including foreign sales, by 1996, and could double the current production rate at its Mesa plant without expanding facilities.

Mooney didn't elaborate on additions the next generation of Apaches will have, but said new armaments, computer equipment and software and other features are added as new enemy threats develop.

The development for the Apache started in 1976 when the helicopter company, then Hughes Helicopters, won the development contract over then-rival McDonnell Douglas, which purchased Hughes before the first production Apache was delivered in 1985.