AIRSTAR HELICOPTER, a Grand Canyon, Arizona-based tour operator, will be the launch customer for the newly unveiled MD 630N if McDonnell Douglas Helicopter Systems (MDHS) decides to go ahead (Flight International, 1-7 February).

AirStar has placed a $20,000 deposit on each of the first two MD 630Ns a seven-to-eight seat stretch version of the NOTAR (no tail rotor) anti-torque system-equipped MD 520N.

AirStar president Ron Williams says: "We're extremely excited about the MD 630N. For years, we've been discussing tour operators' needs with manufacturers and now MDHS has responded."

MDHS could decide to go ahead with the new NOTAR helicopter "as early as April", says its general manager Dean Borgman if it "...warrants enough interest".

MDHS will build a second prototype if the MD 630N receives the go-ahead, says chief engineer Carlo Rao. "The next one will be filled with instrumentation, whereas the first prototype is being used mainly for basic handling qualities and performance work," he says. The first aircraft's arrival at Heli-Expo was one of the surprises of the show.

Rao likens development of the helicopter to a classified programme from its sister company's "Phantom Works". In a walled-off part of MDHS' Mesa, Arizona, site, a small team of engineers stretched a 520N airframe (itself a converted MD 530F demonstrator), by installing a 760mm plug aft of the bulkhead separating the cabin and pilots' seats. To compensate for the larger cabin, a 710mm plug was inserted into the tail-boom. Instead of an aft plug the next prototype will have a lengthened tail-boom built in one piece.

Rao also confirms reports that the 630N suffered engine problems on an early flight, which forced it to make an emergency landing from " about 10ft [3m] or so". MDHS says that the programme has otherwise been faultless, achieving 20h flight time to date and a maximum speed of 130kt (240km/h) in forward flight.

Other changes to the helicopter include a new, heavy-duty, drive system to cope with additional power available from the Allison 250-C30R turbo-shaft. A sixth blade, has also been added to the rotor, to provide more lift for the heavier machine, while the skids have been lengthened by 1m.

MDHS has won an order for up to nine MD 520Ns from the Los Angeles Sheriff's department. Three of the helicopters will be delivered by mid-1995, while the remainder could be handed over by the end of 1996.

The LA Sheriff's department is the ninth law-enforcement agency in the USA and abroad to select the MD 520N.

Source: Flight International